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Sample records for increased proinflammatory signaling

  1. Obesity-Dependent Increases in Oocyte mRNAs Are Associated With Increases in Proinflammatory Signaling and Gut Microbial Abundance of Lachnospiraceae in Female Mice.

    PubMed

    Xie, Fang; Anderson, Christopher L; Timme, Kelsey R; Kurz, Scott G; Fernando, Samodha C; Wood, Jennifer R

    2016-04-01

    RNAs stored in the metaphase II-arrested oocyte play important roles in successful embryonic development. Their abundance is defined by transcriptional activity during oocyte growth and selective degradation of transcripts during LH-induced oocyte maturation. Our previous studies demonstrated that mRNA abundance is increased in mature ovulated oocytes collected from obese humans and mice and therefore may contribute to reduced oocyte developmental competence associated with metabolic dysfunction. In the current study mouse models of diet-induced obesity were used to determine whether obesity-dependent increases in proinflammatory signaling regulate ovarian abundance of oocyte-specific mRNAs. The abundance of oocyte-specific Bnc1, Dppa3, and Pou5f1 mRNAs as well as markers of proinflammatory signaling were significantly increased in ovaries of obese compared with lean mice which were depleted of fully grown preovulatory follicles. Chromatin-immunoprecipitation analyses also demonstrated increased association of phosphorylated signal transducer and activator of transcription 3 with the Pou5f1 promoter in ovaries of obese mice suggesting that proinflammatory signaling regulates transcription of this gene in the oocyte. The cecum microbial content of lean and obese female mice was subsequently examined to identify potential relationships between microbial composition and proinflammatory signaling in the ovary. Multivariate Association with Linear Models identified significant positive correlations between cecum abundance of the bacterial family Lachnospiraceae and ovarian abundance of Tnfa as well as Dppa3, Bnc1, and Pou5f1 mRNAs. Together, these data suggest that diet-induced changes in gut microbial composition may be contributing to ovarian inflammation which in turn alters ovarian gene expression and ultimately contributes to obesity-dependent reduction in oocyte quality and development of infertility in obese patients.

  2. Obesity-Dependent Increases in Oocyte mRNAs Are Associated With Increases in Proinflammatory Signaling and Gut Microbial Abundance of Lachnospiraceae in Female Mice

    PubMed Central

    Xie, Fang; Anderson, Christopher L.; Timme, Kelsey R.; Kurz, Scott G.; Fernando, Samodha C.

    2016-01-01

    RNAs stored in the metaphase II-arrested oocyte play important roles in successful embryonic development. Their abundance is defined by transcriptional activity during oocyte growth and selective degradation of transcripts during LH-induced oocyte maturation. Our previous studies demonstrated that mRNA abundance is increased in mature ovulated oocytes collected from obese humans and mice and therefore may contribute to reduced oocyte developmental competence associated with metabolic dysfunction. In the current study mouse models of diet-induced obesity were used to determine whether obesity-dependent increases in proinflammatory signaling regulate ovarian abundance of oocyte-specific mRNAs. The abundance of oocyte-specific Bnc1, Dppa3, and Pou5f1 mRNAs as well as markers of proinflammatory signaling were significantly increased in ovaries of obese compared with lean mice which were depleted of fully grown preovulatory follicles. Chromatin-immunoprecipitation analyses also demonstrated increased association of phosphorylated signal transducer and activator of transcription 3 with the Pou5f1 promoter in ovaries of obese mice suggesting that proinflammatory signaling regulates transcription of this gene in the oocyte. The cecum microbial content of lean and obese female mice was subsequently examined to identify potential relationships between microbial composition and proinflammatory signaling in the ovary. Multivariate Association with Linear Models identified significant positive correlations between cecum abundance of the bacterial family Lachnospiraceae and ovarian abundance of Tnfa as well as Dppa3, Bnc1, and Pou5f1 mRNAs. Together, these data suggest that diet-induced changes in gut microbial composition may be contributing to ovarian inflammation which in turn alters ovarian gene expression and ultimately contributes to obesity-dependent reduction in oocyte quality and development of infertility in obese patients. PMID:26881311

  3. Acylcarnitines activate proinflammatory signaling pathways.

    PubMed

    Rutkowsky, Jennifer M; Knotts, Trina A; Ono-Moore, Kikumi D; McCoin, Colin S; Huang, Shurong; Schneider, Dina; Singh, Shamsher; Adams, Sean H; Hwang, Daniel H

    2014-06-15

    Incomplete β-oxidation of fatty acids in mitochondria is a feature of insulin resistance and type 2 diabetes mellitus (T2DM). Previous studies revealed that plasma concentrations of medium- and long-chain acylcarnitines (by-products of incomplete β-oxidation) are elevated in T2DM and insulin resistance. In a previous study, we reported that mixed D,L isomers of C12- or C14-carnitine induced an NF-κB-luciferase reporter gene in RAW 264.7 cells, suggesting potential activation of proinflammatory pathways. Here, we determined whether the physiologically relevant L-acylcarnitines activate classical proinflammatory signaling pathways and if these outcomes involve pattern recognition receptor (PRR)-associated pathways. Acylcarnitines induced the expression of cyclooxygenase-2 in a chain length-dependent manner in RAW 264.7 cells. L-C14 carnitine (5-25 μM), used as a representative acylcarnitine, stimulated the expression and secretion of proinflammatory cytokines in a dose-dependent manner. Furthermore, L-C14 carnitine induced phosphorylation of JNK and ERK, common downstream components of many proinflammatory signaling pathways including PRRs. Knockdown of MyD88, a key cofactor in PRR signaling and inflammation, blunted the proinflammatory effects of acylcarnitine. While these results point to potential involvement of PRRs, L-C14 carnitine promoted IL-8 secretion from human epithelial cells (HCT-116) lacking Toll-like receptors (TLR)2 and -4, and did not activate reporter constructs in TLR overexpression cell models. Thus, acylcarnitines have the potential to activate inflammation, but the specific molecular and tissue target(s) involved remain to be identified.

  4. Acylcarnitines activate proinflammatory signaling pathways

    PubMed Central

    Rutkowsky, Jennifer M.; Knotts, Trina A.; Ono-Moore, Kikumi D.; McCoin, Colin S.; Huang, Shurong; Schneider, Dina; Singh, Shamsher; Hwang, Daniel H.

    2014-01-01

    Incomplete β-oxidation of fatty acids in mitochondria is a feature of insulin resistance and type 2 diabetes mellitus (T2DM). Previous studies revealed that plasma concentrations of medium- and long-chain acylcarnitines (by-products of incomplete β-oxidation) are elevated in T2DM and insulin resistance. In a previous study, we reported that mixed d,l isomers of C12- or C14-carnitine induced an NF-κB-luciferase reporter gene in RAW 264.7 cells, suggesting potential activation of proinflammatory pathways. Here, we determined whether the physiologically relevant l-acylcarnitines activate classical proinflammatory signaling pathways and if these outcomes involve pattern recognition receptor (PRR)-associated pathways. Acylcarnitines induced the expression of cyclooxygenase-2 in a chain length-dependent manner in RAW 264.7 cells. l-C14 carnitine (5–25 μM), used as a representative acylcarnitine, stimulated the expression and secretion of proinflammatory cytokines in a dose-dependent manner. Furthermore, l-C14 carnitine induced phosphorylation of JNK and ERK, common downstream components of many proinflammatory signaling pathways including PRRs. Knockdown of MyD88, a key cofactor in PRR signaling and inflammation, blunted the proinflammatory effects of acylcarnitine. While these results point to potential involvement of PRRs, l-C14 carnitine promoted IL-8 secretion from human epithelial cells (HCT-116) lacking Toll-like receptors (TLR)2 and -4, and did not activate reporter constructs in TLR overexpression cell models. Thus, acylcarnitines have the potential to activate inflammation, but the specific molecular and tissue target(s) involved remain to be identified. PMID:24760988

  5. Adenosine Signaling Increases Proinflammatory and Profibrotic Mediators through Activation of a Functional Adenosine 2B Receptor in Renal Fibroblasts.

    PubMed

    Wilkinson, Patrick F; Farrell, Francis X; Morel, Diane; Law, William; Murphy, Suzanne

    2016-07-01

    Interstitial renal fibrosis is a major pathophysiological manifestation of patients diagnosed with Chronic Kidney Disease (CKD), Diabetic Nephropathy (DN) and other inflammatory diseases. Adenosine signaling is an innate autocrine and paracrine cellular signaling pathway involving several key mediators that are elevated in the blood and kidneys of patients with DN. In these studies, we hypothesized that extracellular adenosine signals through one or more functional adenosine GPCRs on renal fibroblasts which increases profibrotic and proinflammatory mediators by inducing an activated fibroblast phenotype. Utilizing the renal fibroblast cell line NRK-49F, the presence and relative abundance of adenosine receptors (AR) A1, A2A, A2B, and A3 were quantified by RT-PCR. Under normal homeostatic conditions, only AR1 and AR2B were detected. The functionality of each receptor was then assessed by receptor specific pharmacological agonism and antagonism and assessed for modulation of the GPCR associated secondary messenger molecule, cyclic adenosine monophosphate (cAMP). Agonism of the AR2B receptor resulted in increased intracellular cAMP while agonism of the AR1 receptor inhibited cAMP modulation. Upon direct agonism of the AR2B receptor, transcripts for profibrotic and inflammatory mediators including SMA-α, IL-6, TGF-β, CTGF, and fibronectin were elevated between 2-4 fold. These data indicate that renal fibroblasts express a functional AR1 receptor that inhibits cAMP upon stimulation, leading to a functional AR2B receptor that increases cAMP upon stimulation and also induces an activated fibroblast phenotype resulting in increased fibrotic and inflammatory mediators.

  6. Low early-life social class leaves a biological residue manifested by decreased glucocorticoid and increased proinflammatory signaling.

    PubMed

    Miller, Gregory E; Chen, Edith; Fok, Alexandra K; Walker, Hope; Lim, Alvin; Nicholls, Erin F; Cole, Steve; Kobor, Michael S

    2009-08-25

    Children reared in unfavorable socioeconomic circumstances show increased susceptibility to the chronic diseases of aging when they reach the fifth and sixth decades of life. One mechanistic hypothesis for this phenomenon suggests that social adversity in early life programs biological systems in a manner that persists across decades and thereby accentuates vulnerability to disease. Here we examine the basic tenets of this hypothesis by performing genome-wide transcriptional profiling in healthy adults who were either low or high in socioeconomic status (SES) in early life. Among subjects with low early-life SES, there was significant up-regulation of genes bearing response elements for the CREB/ATF family of transcription factors that conveys adrenergic signals to leukocytes, and significant down-regulation of genes with response elements for the glucocorticoid receptor, which regulates the secretion of cortisol and transduces its antiinflammatory actions in the immune system. Subjects from low-SES backgrounds also showed increased output of cortisol in daily life, heightened expression of transcripts bearing response elements for NF-kappaB, and greater stimulated production of the proinflammatory cytokine interleukin 6. These disparities were independent of subjects' current SES, lifestyle practices, and perceived stress. Collectively, these data suggest that low early-life SES programs a defensive phenotype characterized by resistance to glucocorticoid signaling, which in turn facilitates exaggerated adrenocortical and inflammatory responses. Although these response patterns could serve adaptive functions during acute threats to well-being, over the long term they might exact an allostatic toll on the body that ultimately contributes to the chronic diseases of aging.

  7. Proinflammatory signaling regulates hematopoietic stem cell emergence

    PubMed Central

    Espín-Palazón, Raquel; Stachura, David L.; Campbell, Clyde A.; García-Moreno, Diana; Cid, Natasha Del; Kim, Albert D.; Candel, Sergio; Meseguer, José; Mulero, Victoriano; Traver, David

    2014-01-01

    Summary Hematopoietic stem cells (HSCs) underlie the production of blood and immune cells for the lifetime of an organism. In vertebrate embryos, HSCs arise from the unique transdifferentiation of hemogenic endothelium comprising the floor of the dorsal aorta during a brief developmental window. To date, this process has not been replicated in vitro from pluripotent precursors, partly because the full complement of required signaling inputs remains to be determined. Here, we show that TNFR2 via TNFα activates the Notch and NF-κB signaling pathways to establish HSC fate, indicating a requirement for inflammatory signaling in HSC generation. We determine that primitive neutrophils are the major source of TNFα, assigning a role for transient innate immune cells in establishing the HSC program. These results demonstrate that proinflammatory signaling, in the absence of infection, is utilized by the developing embryo to generate the lineal precursors of the adult hematopoietic system. PMID:25416946

  8. Epithelial uptake of flagella initiates proinflammatory signaling.

    PubMed

    Parker, Dane; Prince, Alice

    2013-01-01

    The airway epithelium serves multiple roles in the defense of the lung. Not only does it act as a physical barrier, it acts as a distal extension of the innate immune system. We investigated the role of the airway epithelium in the interaction with flagella, an important virulence factor of the pathogen Pseudomonas aeruginosa, a cause of ventilator associated pneumonia and significant morbidity and mortality in patients with cystic fibrosis. Flagella were required for transmigration across polarized airway epithelial cells and this was a direct consequence of motility, and not a signaling effect. Purified flagella did not alter the barrier properties of the epithelium but were observed to be rapidly endocytosed inside epithelial cells. Neither flagella nor intact P. aeruginosa stimulated epithelial inflammasome signaling. Flagella-dependent signaling required dynamin-based uptake as well as TLR5 and primarily led to the induction of proinflammatory (Tnf, Il6) as well as neutrophil (Cxcl1, Cxcl2, Ccl3) and macrophage (Ccl20) chemokines. Although flagella are important in invasion across the epithelial barrier their shedding in the airway lumen results in epithelial uptake and signaling that has a major role in the initial recruitment of immune cells in the lung.

  9. Krüppel-Like Factor 4 Is a Regulator of Proinflammatory Signaling in Fibroblast-Like Synoviocytes through Increased IL-6 Expression

    PubMed Central

    Ruan, Jianwei; Xie, Jiangwen; Lv, Guoju

    2016-01-01

    Human fibroblast-like synoviocytes play a vital role in joint synovial inflammation in rheumatoid arthritis (RA). Proinflammatory cytokines induce fibroblast-like synoviocyte activation and dysfunction. The inflammatory mediator Krüppel-like factor 4 is upregulated during inflammation and plays an important role in endothelial and macrophage activation during inflammation. However, the role of Krüppel-like factor 4 in fibroblast-like synoviocyte activation and RA inflammation remains to be defined. In this study, we identify the notion that Krüppel-like factor 4 is higher expressed in synovial tissues and fibroblast-like synoviocytes from RA patients than those from osteoarthritis patients. In vitro, the expression of Krüppel-like factor 4 in RA fibroblast-like synoviocytes is induced by proinflammatory cytokine tumor necrosis factor-α. Overexpression of Krüppel-like factor 4 in RA fibroblast-like synoviocytes robustly induced interleukin-6 production in the presence or absence of tumor necrosis factor-α. Conversely, knockdown of Krüppel-like factor 4 markedly attenuated interleukin-6 production in the presence or absence of tumor necrosis factor-α. Krüppel-like factor 4 not only can bind to and activate the interleukin-6 promoter, but also may interact directly with nuclear factor-kappa B. These results suggest that Krüppel-like factor 4 may act as a transcription factor mediating the activation of fibroblast-like synoviocytes in RA by inducing interleukin-6 expression in response to tumor necrosis factor-α. PMID:27413250

  10. Lipin-2 reduces proinflammatory signaling induced by saturated fatty acids in macrophages.

    PubMed

    Valdearcos, Martín; Esquinas, Esperanza; Meana, Clara; Peña, Lucía; Gil-de-Gómez, Luis; Balsinde, Jesús; Balboa, María A

    2012-03-30

    Lipin-2 is a member of the lipin family of enzymes, which are key effectors in the biosynthesis of lipids. Mutations in the human lipin-2 gene are associated with inflammatory-based disorders; however, the role of lipin-2 in cells of the immune system remains obscure. In this study, we have investigated the role of lipin-2 in the proinflammatory action of saturated fatty acids in murine and human macrophages. Depletion of lipin-2 promotes the increased expression of the proinflammatory genes Il6, Ccl2, and Tnfα, which depends on the overstimulation of the JNK1/c-Jun pathway by saturated fatty acids. In contrast, overexpression of lipin-2 reduces the release of proinflammatory factors. Metabolically, the absence of lipin-2 reduces the cellular content of triacylglycerol in saturated fatty acid-overloaded macrophages. Collectively, these studies demonstrate a protective role for lipin-2 in proinflammatory signaling mediated by saturated fatty acids that occurs concomitant with an enhanced cellular capacity for triacylglycerol synthesis. The data provide new insights into the role of lipin-2 in human and murine macrophage biology and may open new avenues for controlling the fatty acid-related low grade inflammation that constitutes the sine qua non of obesity and associated metabolic disorders.

  11. Early Attachment-Figure Separation and Increased Risk for Later Depression: Potential Mediation by Proinflammatory Processes

    PubMed Central

    Hennessy, Michael B.; Deak, Terrence; Schiml-Webb, Patricia A.

    2009-01-01

    Early maternal separation and other disruptions of attachment relations are known to increase risk for the later onset of depressive illness in vulnerable individuals. It is suggested here that sensitization involving proinflammatory processes may contribute to this effect. This argument is based on: (1) current notions of the role of proinflammatory cytokines in depressive illness; (2) evidence that proinflammatory cytokines mediate depressive-like behavior during separation in a rodent model of infant attachment; and (3) comparisons of the effects of early proinflammatory activation versus maternal separation on later proinflammatory activity and biobehavioral processes related to depression. The possible interaction of proinflammatory processes and corticotropin-releasing factor in the sensitization process is discussed. PMID:20359585

  12. Expression of tak1 and tram induces synergistic pro-inflammatory signalling and adjuvants DNA vaccines.

    PubMed

    Larsen, Karen Colbjørn; Spencer, Alexandra J; Goodman, Anna L; Gilchrist, Ashley; Furze, Julie; Rollier, Christine S; Kiss-Toth, Endre; Gilbert, Sarah C; Bregu, Migena; Soilleux, Elizabeth J; Hill, Adrian V S; Wyllie, David H

    2009-09-18

    Improving vaccine immunogenicity remains a major challenge in the fight against developing country diseases like malaria and AIDS. We describe a novel strategy to identify new DNA vaccine adjuvants. We have screened components of the Toll-like receptor signalling pathways for their ability to activate pro-inflammatory target genes in transient transfection assays and assessed in vivo adjuvant activity by expressing the activators from the DNA backbone of vaccines. We find that a robust increase in the immune response necessitates co-expression of two activators. Accordingly, the combination of tak1 and tram elicits synergistic reporter activation in transient transfection assays. In a mouse model this combination, but not the individual molecules, induced approximately twofold increases in CD8+ T-cell immune responses. These results indicate that optimal immunogenicity may require activation of distinct innate immune signalling pathways. Thus this strategy offers a novel route to the discovery of a new generation of adjuvants.

  13. Reduced tissue osmolarity increases TRPV4 expression and pro-inflammatory cytokines in intervertebral disc cells.

    PubMed

    Walter, B A; Purmessur, D; Moon, A; Occhiogrosso, J; Laudier, D M; Hecht, A C; Iatridis, J C

    2016-07-19

    The mechanical behaviour and cellular metabolism of intervertebral discs (IVDs) and articular cartilage are strongly influenced by their proteoglycan content and associated osmotic properties. This osmotic environment is a biophysical signal that changes with disease and may contribute to the elevated matrix breakdown and altered biologic response to loading observed in IVD degeneration and osteoarthritis. This study tested the hypothesis that changes in osmo-sensation by the transient receptor potential vallinoid-4 (TRPV4) ion channel occur with disease and contribute to the inflammatory environment found during degeneration. Immunohistochemistry on bovine IVDs from an inflammatory organ culture model were used to investigate if TRPV4 is expressed in the IVD and how expression changes with degeneration. Western blot, live-cell calcium imaging, and qRT-PCR were used to investigate whether osmolarity changes or tumour necrosis factor α (TNFα) regulate TRPV4 expression, and how altered TRPV4 expression influences calcium signalling and pro-inflammatory cytokine expression. TRPV4 expression correlated with TNFα expression, and was increased when cultured in reduced medium osmolarity and unaltered with TNFα-stimulation. Increased TRPV4 expression increased the calcium flux following TRPV4 activation and increased interleukin-1β (IL-1β) and IL-6 gene expression in IVD cells. TRPV4 expression was qualitatively elevated in regions of aggrecan depletion in degenerated human IVDs. Collectively, results suggest that reduced tissue osmolarity, likely following proteoglycan degradation, can increase TRPV4 signalling and enhance pro-inflammatory cytokine production, suggesting changes in TRPV4 mediated osmo-sensation may contribute to the progressive matrix breakdown in disease.

  14. REDUCED TISSUE OSMOLARITY INCREASES TRPV4 EXPRESSION AND PRO-INFLAMMATORY CYTOKINES IN INTERVERTEBRAL DISC CELLS

    PubMed Central

    Walter, B.A.; Purmessur, D; Moon, A.; Occhiogrosso, J.; Laudier, D.M.; Hecht, A.C.; Iatridis, J.C.

    2016-01-01

    The mechanical behaviour and cellular metabolism of intervertebral discs (IVDs) and articular cartilage are strongly influenced by their proteoglycan content and associated osmotic properties. This osmotic environment is a biophysical signal that changes with disease and may contribute to the elevated matrix breakdown and altered biologic response to loading observed in IVD degeneration and osteoarthritis. This study tested the hypothesis that changes in osmo-sensation by the transient receptor potential vallinoid-4 (TRPV4) ion channel occur with disease and contribute to the inflammatory environment found during degeneration. Immunohistochemistry on bovine IVDs from an inflammatory organ culture model were used to investigate if TRPV4 is expressed in the IVD and how expression changes with degeneration. Western blot, live-cell calcium imaging, and qRT-PCR were used to investigate whether osmolarity changes or tumour necrosis factor α (TNFα) regulate TRPV4 expression, and how altered TRPV4 expression influences calcium signalling and pro-inflammatory cytokine expression. TRPV4 expression correlated with TNFα expression, and was increased when cultured in reduced medium osmolarity and unaltered with TNFα-stimulation. Increased TRPV4 expression increased the calcium flux following TRPV4 activation and increased interleukin-1β (IL-1β) and IL-6 gene expression in IVD cells. TRPV4 expression was qualitatively elevated in regions of aggrecan depletion in degenerated human IVDs. Collectively, results suggest that reduced tissue osmolarity, likely following proteoglycan degradation, can increase TRPV4 signalling and enhance pro-inflammatory cytokine production, suggesting changes in TRPV4 mediated osmo-sensation may contribute to the progressive matrix breakdown in disease. PMID:27434269

  15. Chemically induced neuronal damage and gliosis: enhanced expression of the proinflammatory chemokine, monocyte chemoattractant protein (MCP)-1, without a corresponding increase in proinflammatory cytokines(1).

    PubMed

    Little, A R; Benkovic, S A; Miller, D B; O'Callaghan, J P

    2002-01-01

    Enhanced expression of proinflammatory cytokines and chemokines has long been linked to neuronal and glial responses to brain injury. Indeed, inflammation in the brain has been associated with damage that stems from conditions as diverse as infection, multiple sclerosis, trauma, and excitotoxicity. In many of these brain injuries, disruption of the blood-brain barrier (BBB) may allow entry of blood-borne factors that contribute to, or serve as the basis of, brain inflammatory responses. Administration of trimethyltin (TMT) to the rat results in loss of hippocampal neurons and an ensuing gliosis without BBB compromise. We used the TMT damage model to discover the proinflammatory cytokines and chemokines that are expressed in response to neuronal injury. TMT caused pyramidal cell damage within 3 days and a substantial loss of these neurons by 21 days post dosing. Marked microglial activation and astrogliosis were evident over the same time period. The BBB remained intact despite the presence of multiple indicators of TMT-induced neuropathology. TMT caused large increases in whole hippocampal-derived monocyte chemoattractant protein (MCP)-1 mRNA (1,000%) by day 3 and in MCP-1 (300%) by day 7. The mRNA levels for tumor necrosis factor (TNF)-alpha, interleukin (IL)-1beta and IL-6, cytokines normally expressed during the earliest stage of inflammation, were not increased up to 21 days post dosing. Lipopolysaccharide, used as a positive control, caused large inductions of cytokine mRNA in liver, as well as an increase in IL-1beta in hippocampus, but it did not result in the induction of astrogliosis. The data suggest that enhanced expression of the proinflammatory cytokines, TNF-alpha, IL-1beta and IL-6, is not required for neuronal and glial responses to injury and that MCP-1 may serve a signaling function in the damaged CNS that is distinct from its role in proinflammatory events.

  16. Saturated fatty acids activate TLR-mediated proinflammatory signaling pathways.

    PubMed

    Huang, Shurong; Rutkowsky, Jennifer M; Snodgrass, Ryan G; Ono-Moore, Kikumi D; Schneider, Dina A; Newman, John W; Adams, Sean H; Hwang, Daniel H

    2012-09-01

    Toll-like receptor 4 (TLR4) and TLR2 were shown to be activated by saturated fatty acids (SFAs) but inhibited by docosahexaenoic acid (DHA). However, one report suggested that SFA-induced TLR activation in cell culture systems is due to contaminants in BSA used for solubilizing fatty acids. This report raised doubt about proinflammatory effects of SFAs. Our studies herein demonstrate that sodium palmitate (C16:0) or laurate (C12:0) without BSA solubilization induced phosphorylation of inhibitor of nuclear factor-κB α, c-Jun N-terminal kinase (JNK), p44/42 mitogen-activated-kinase (ERK), and nuclear factor-κB subunit p65, and TLR target gene expression in THP1 monocytes or RAW264.7 macrophages, respectively, when cultured in low FBS (0.25%) medium. C12:0 induced NFκB activation through TLR2 dimerized with TLR1 or TLR6, and through TLR4. Because BSA was not used in these experiments, contaminants in BSA have no relevance. Unlike in suspension cells (THP-1), BSA-solubilized C16:0 instead of sodium C16:0 is required to induce TLR target gene expression in adherent cells (RAW264.7). C16:0-BSA transactivated TLR2 dimerized with TLR1 or TLR6 and through TLR4 as seen with C12:0. These results and additional studies with the LPS sequester polymixin B and in MyD88(-/-) macrophages indicated that SFA-induced activation of TLR2 or TLR4 is a fatty acid-specific effect, but not due to contaminants in BSA or fatty acid preparations.

  17. Activation of proinflammatory signaling by 4-hydroxynonenal-Src adducts in aged kidneys

    PubMed Central

    Lee, Bonggi; Lee, Eun Kyeong; Chung, Ki Wung; Moon, Kyoung Mi; Kim, Min Jo; An, Hye Jin; Jeong, Ji Won; Kim, Ye Ra; Yu, Byung Pal; Chung, Hae Young

    2016-01-01

    In our previous study, reactive 4-hydroxy-2-nonenal (4-HNE) was shown to activate Src (a non-receptor tyrosine kinase) by forming an adduct on binding with a specific residue of Src, leading to the activation of proinflammatory signaling pathways in cultured cells. However, to date, the deleterious roles of 4-HNE in inflammatory signaling activation in kidneys during aging have not been explored. The purpose of the present study was to document the mechanisms by which 4-HNE induces inflammation in the kidney during aging. Initial experiments revealed that activated nuclear factor-κB (NF-κB) expression was caused by 4-HNE activation, which suppressed transcriptional activity in the aged kidney. Treatment of human umbilical vein endothelial cells with 4-HNE revealed that Src caused senescence via NF-κB activation. Furthermore, our immunohistochemistry data showed that 4-HNE-adducted Src significantly increased in aged kidney tissues. The data showed age-related upregulation of downstream signaling molecules such as mitogen activated protein kinases (MAPKs), activator protein-1 (AP-1), NF-κB, and COX-2 in a cell culture cell system. Taken together, the results of this study show that the formation of adducts between 4-HNE and Src activates inflammatory signaling pathways in the aged kidney, contributing to age-related nephropathy. PMID:27472463

  18. Proinflammatory Cytokine IL-6 and JAK-STAT Signaling Pathway in Myeloproliferative Neoplasms

    PubMed Central

    Čokić, Vladan P.; Mitrović-Ajtić, Olivera; Beleslin-Čokić, Bojana B.; Marković, Dragana; Buač, Marijana; Diklić, Miloš; Kraguljac-Kurtović, Nada; Damjanović, Svetozar; Milenković, Pavle; Gotić, Mirjana; Raj, Puri K.

    2015-01-01

    The recent JAK1/2 inhibitor trial in myeloproliferative neoplasms (MPNs) showed that reducing inflammation can be more beneficial than targeting gene mutants. We evaluated the proinflammatory IL-6 cytokine and JAK-STAT signaling pathway related genes in circulating CD34+ cells of MPNs. Regarding laboratory data, leukocytosis has been observed in polycythemia vera (PV) and JAK2V617F mutation positive versus negative primary myelofibrosis (PMF) patients. Moreover, thrombocytosis was reduced by JAK2V617F allele burden in essential thrombocythemia (ET) and PMF. 261 significantly changed genes have been detected in PV, 82 in ET, and 94 genes in PMF. The following JAK-STAT signaling pathway related genes had augmented expression in CD34+ cells of MPNs: CCND3 and IL23A regardless of JAK2V617F allele burden; CSF3R, IL6ST, and STAT1/2 in ET and PV with JAK2V617F mutation; and AKT2, IFNGR2, PIM1, PTPN11, and STAT3 only in PV. STAT5A gene expression was generally reduced in MPNs. IL-6 cytokine levels were increased in plasma, as well as IL-6 protein levels in bone marrow stroma of MPNs, dependent on JAK2V617F mutation presence in ET and PMF patients. Therefore, the JAK2V617F mutant allele burden participated in inflammation biomarkers induction and related signaling pathways activation in MPNs. PMID:26491227

  19. TREM2/DAP12 Signal Elicits Proinflammatory Response in Microglia and Exacerbates Neuropathic Pain.

    PubMed

    Kobayashi, Masaaki; Konishi, Hiroyuki; Sayo, Akira; Takai, Toshiyuki; Kiyama, Hiroshi

    2016-10-26

    Neuropathic pain afflicts millions of people, and the development of an effective treatment for this intractable pain is an urgent issue. Recent evidence has implicated microglia in neuropathic pain. The present study showed that the DNAX-activating protein of 12 kDa (DAP12) and its associated "triggering receptor expressed on myeloid cells 2" (TREM2) were predominantly expressed by microglia in the dorsal horn after spinal nerve injury, revealing a role for TREM2/DAP12 signaling in neuropathic pain. Nerve injury-induced proinflammatory cytokine expression in microglia and pain behaviors were significantly suppressed in Dap12-deficient mice. Furthermore, intrathecal administration of TREM2 agonistic antibody induced proinflammatory cytokine expression, as well as neuropathic pain, in mice without nerve injury. The agonistic antibody induced proinflammatory responses and neuropathic pain was not observed in Dap12-deficient mice. Together, these results suggest that TREM2/DAP12-mediated signals in microglia exacerbate nerve injury-induced neuropathic pain by inducing proinflammatory cytokine secretion from microglia. Suppression of DAP12-mediated signals could be a therapeutic target for neuropathic pain. Recent studies have revealed that activated microglia in the spinal dorsal horn exacerbate neuropathic pain, which has suggested that suppression of microglial activity should be considered as a therapeutic target. However, only a few molecules have been identified as regulators of microglial activity. In this study, we focused on a receptor complex of TREM2 and DAP12, both of which are expressed by microglia and have been implicated in the pathogenesis of Alzheimer's disease, and demonstrated that TREM2/DAP12 signaling promoted proinflammatory responses in microglia and exacerbates neuropathic pain. The present results revealed the functional significance of TREM2/DAP12 signaling in microglial activation after neuronal injury, and could help in the development of

  20. Proinflammatory Cytokines Increase Vascular Endothelial Growth Factor Expression in Alveolar Epithelial Cells.

    PubMed

    Maloney, James P; Gao, Li

    2015-01-01

    Vascular endothelial growth factor (VEGF) is an endothelial permeability mediator that is highly expressed in lung epithelium. In nonlung cells proinflammatory cytokines have been shown to increase VEGF expression, but their effects on lung epithelium remain unclear. We hypothesized that increases in alveolar epithelial cell VEGF RNA and protein expression occur after exposure to proinflammatory cytokines. We tested this using human alveolar epithelial cells (A549) stimulated with 5 proinflammatory cytokines. VEGF RNA expression was increased 1.4-2.7-fold in response to IL-1, IL-6, IL-8, TNF-α, or TGF-β over 6 hours, with TGF-β having the largest response. TNF-α increased VEGF RNA as early as 1 hour. A mix of IL-1, IL-6, and IL-8 had effects similar to IL-1. TNF-α increased protein expression as early as 4 hours and had a sustained effect at 16 hours, whereas IL-1 did not increase protein expression. Only VEGF165 was present in cultured A549 cells, yet other isoforms were seen in human lung tissue. Increased expression of VEGF in alveolar epithelial cells occurs in response to proinflammatory cytokines. Increased VEGF expression likely contributes to the pathogenesis of inflammatory lung diseases and to the angiogenic phenotype of lung cancer, a disease typically preceded by chronic inflammation.

  1. Host Intracellular Signaling Events and Pro-inflammatory Cytokine Production in African Trypanosomiasis

    PubMed Central

    Kuriakose, Shiby M.; Singh, Rani; Uzonna, Jude E.

    2016-01-01

    Pathogens, such as bacteria, viruses, and parasites, possess specific molecules or proteins that are recognized by several host innate immune receptors, leading to the activation of several intracellular signaling molecules and pathways. The magnitude and quality of these events significantly affect the outcome of infection. African trypanosomes, including Trypanosoma congolense, are capable of manipulating the host immune response, including the activity of macrophages, which are the key immune cells that contribute to the immunopathogenesis of African trypanosomiasis. Although it is known that immune hyperactivation and excessive pro-inflammatory cytokine production are the hallmarks of African trypanosomiasis, the mechanisms through which these events are triggered are poorly defined. However, it is known that macrophages may play a significant role in these processes, because phagocytosis of trypanosomes by macrophages initiates intracellular signal transduction cascades that lead to the release of pro-inflammatory cytokines and alteration in cell function. This review highlights recent progress in our understanding of the innate immune receptors, signaling pathways, and transcription factors involved in T. congolense-induced pro-inflammatory cytokine production in macrophages. It will reveal the existence of complex signaling events through which the parasite modulates the host immune response, thus identifying novel targets that could aid in designing strategies to effectively control the disease. PMID:27242788

  2. ErbB4 signaling stimulates pro-inflammatory macrophage apoptosis and limits colonic inflammation

    PubMed Central

    Schumacher, Michael A; Hedl, Matija; Abraham, Clara; Bernard, Jessica K; Lozano, Patricia R; Hsieh, Jonathan J; Almohazey, Dana; Bucar, Edie B; Punit, Shivesh; Dempsey, Peter J; Frey, Mark R

    2017-01-01

    Efficient clearance of pro-inflammatory macrophages from tissues after resolution of a challenge is critical to prevent prolonged inflammation. Defects in clearance can contribute to conditions such as inflammatory bowel disease, and thus may be therapeutically targetable. However, the signaling pathways that induce termination of pro-inflammatory macrophages are incompletely defined. We tested whether the ErbB4 receptor tyrosine kinase, previously not known to have role in macrophage biology, is involved in this process. In vitro, pro-inflammatory activation of cultured murine and human macrophages induced ErbB4 expression; in contrast, other ErbB family members were not induced in pro-inflammatory cells, and other innate immune lineages (dendritic cells, neutrophils) did not express detectable ErbB4 levels. Treatment of activated pro-inflammatory macrophages with the ErbB4 ligand neuregulin-4 (NRG4) induced apoptosis. ErbB4 localized to the mitochondria in these cells. Apoptosis was accompanied by loss of mitochondrial membrane potential, and was dependent upon the proteases that generate the cleaved ErbB4 intracellular domain fragment, suggesting a requirement for this fragment and mitochondrial pathway apoptosis. In vivo, ErbB4 was highly expressed on pro-inflammatory macrophages but not neutrophils during experimental DSS colitis in C57Bl/6 mice. Active inflammation in this model suppressed NRG4 expression, which may allow for macrophage persistence and ongoing inflammation. Consistent with this notion, NRG4 levels rebounded during the recovery phase, and administration of exogenous NRG4 during colitis reduced colonic macrophage numbers and ameliorated inflammation. These data define a novel role for ErbB4 in macrophage apoptosis, and outline a mechanism of feedback inhibition that may promote resolution of colitis. PMID:28230865

  3. Increased Peripheral Proinflammatory T Helper Subsets Contribute to Cardiovascular Complications in Diabetic Patients

    PubMed Central

    Zhao, Ru-xing; Li, Wen-juan; Lu, Yi-ran; Qin, Jun; Wu, Chuan-long; Tian, Meng; He, Tian-yi; Yi, Shou-nan; Tang, Dong-qi; Sun, Lei; Chen, Li

    2014-01-01

    Background. Coronary atherosclerotic heart disease (CHD) is one of the major concerns in type 2 diabetes (T2D). The systemic chronic inflammation has been postulated to bridge the increased risk of cardiovascular disease and T2D. We formulated that increased peripheral proinflammatory T helper subsets contributed to the development of cardiovascular complications in diabetic patients. Methods. The frequencies of peripheral total CD4+ T helper cells, proinflammatory Th1, Th17, and Th22 subsets were determined by flow cytometry in diabetic patients with or without CHD (n = 42 and 67, resp.). Results. Both peripheral frequencies and total numbers of Th1, Th17, and Th22 cells were further increased in diabetic patients with CHD. Logistic regression and categorical cross-table analysis further confirmed that increased proinflammatory Th subsets, especially Th22, were independent risk factors of cardiovascular complication in diabetes. Elevated Th subsets also correlated with increased CRP levels and the atherogenic index of plasma. Moreover, Th1 frequency and Th22 numbers demonstrated remarkable potential in predicting CHD in diabetes. Conclusions. Increased peripheral proinflammatory T helper subsets act in concert and contribute to the increased prevalence of diabetic cardiovasculopathy. The recently identified Th22 cells might play an independent role in CHD and represent a novel proxy for cardiovascular risks in diabetes. PMID:24803740

  4. A20 suppresses vascular inflammation by recruiting proinflammatory signaling molecules to intracellular aggresomes

    PubMed Central

    Enesa, Karine; Moll, Herwig P.; Luong, Le; Ferran, Christiane; Evans, Paul C.

    2015-01-01

    A20 protects against pathologic vascular remodeling by inhibiting the inflammatory transcription factor NF-κB. A20’s function has been attributed to ubiquitin editing of receptor-interacting protein 1 (RIP1) to influence activity/stability. The validity of this mechanism was tested using a murine model of transplant vasculopathy and human cells. Mouse C57BL/6 aortae transduced with adenoviruses containing A20 (or β-galactosidase as a control) were allografted into major histocompatibility complex-mismatched BALB/c mice. Primary endothelial cells, smooth muscle cells, or transformed epithelial cells (all human) were transfected with wild-type A20 or with catalytically inactive mutants as a control. NF-κB activity and intracellular localization of RIP1 was monitored by reporter gene assay, immunofluorescent staining, and Western blotting. Native and catalytically inactive versions of A20 had similar inhibitory effects on NF-κB activity (−70% vs. −76%; P > 0.05). A20 promoted localization of RIP1 to insoluble aggresomes in murine vascular allografts and in human cells (53% vs. 0%) without altering RIP1 expression, and this process was increased by the assembly of polyubiquitin chains (87% vs. 28%; P < 0.05). A20 captures polyubiquitinated signaling intermediaries in insoluble aggresomes, thus reducing their bioavailability for downstream NF-κB signaling. This novel mechanism contributes to protection from vasculopathy in transplanted organs treated with exogenous A20.—Enesa, K., Moll, H. P., Luong, L., Ferran, C., Evans, P. C. A20 suppresses vascular inflammation by recruiting proinflammatory signaling molecules to intracellular aggresomes. PMID:25667218

  5. Cerebral mTOR signal and pro-inflammatory cytokines in Alzheimer’s disease rats

    PubMed Central

    Wang, Xu; Li, Guang-Jian; Hu, Hai-Xia; Ma, Chi; Ma, Di-Hui; Liu, Xiao-Liang

    2016-01-01

    Abstract As a part of Alzheimer’s disease (AD) development the mammalian target of rapamycin (mTOR) has been reported to play a crucial role in regulating cognition and can be used as a neuronal marker. Neuro-inflammation is also a cause of the pathophysiological process in AD. Thus, we examined the protein expression levels of mTOR and its downstream pathways as well as pro-inflammatory cytokines (PICs) in the brain of AD rats. We further examined the effects of blocking mTOR on PICs, namely IL-1β, IL-6 and TNF-α. Our results showed that the protein expression of p-mTOR, mTOR-mediated phosphorylation of 4E-binding protein 4 (4E-BP1) and p70 ribosomal S6 protein kinase 1 (S6K1) pathways were amplified in the hippocampus of AD rats compared with controls. Blocking mTOR by using rapamycin selectively enhanced activities of IL-6 and TNF-α signaling pathways, which was accompanied with an increase of Caspase-3, indicating cellular apoptosis and worsened learning performance. In conclusion, our data for the first time revealed specific signaling pathways engaged in the development of AD, including a regulatory role by the activation of mTOR in PIC mechanisms. Stimulation of mTOR is likely to play a beneficial role in modulating neurological deficits in AD.Targeting one or more of these signaling molecules may present with new opportunities for treatment and clinical management of AD PMID:28123835

  6. Rationale and Means to Target Pro-Inflammatory Interleukin-8 (CXCL8) Signaling in Cancer

    PubMed Central

    Campbell, Laura M.; Maxwell, Pamela J.; Waugh, David J.J.

    2013-01-01

    It is well established that chronic inflammation underpins the development of a number of human cancers, with pro-inflammatory signaling within the tumor microenvironment contributing to tumor progression and metastasis. CXCL8 is an ELR+ pro-inflammatory CXC-chemokine which mediates its effects via signaling through two G protein-coupled receptors, CXCR1 and CXCR2. Elevated CXCL8-CXCR1/2 signaling within the tumor microenvironment of numerous cancers is known to enhance tumor progression via activation of signaling pathways promoting proliferation, angiogenesis, migration, invasion and cell survival. This review provides an overview of established roles of CXCL8-CXCR1/2 signaling in cancer and subsequently, discusses the possible strategies of targeting CXCL8-CXCR1/2 signaling in cancer, covering indirect strategies (e.g., anti-inflammatories, NFκB inhibitors) and direct CXCL8 or CXCR1/2 inhibition (e.g., neutralizing antibodies, small molecule receptor antagonists, pepducin inhibitors and siRNA strategies). Reports of pre-clinical cancer studies and clinical trials using CXCL8-CXCR1/2-targeting strategies for the treatment of inflammatory diseases will be discussed. The future translational opportunities for use of such agents in oncology will be discussed, with emphasis on exploitation in stratified populations. PMID:24276377

  7. Mild hyperhomocysteinemia increases brain acetylcholinesterase and proinflammatory cytokine levels in different tissues.

    PubMed

    Scherer, Emilene B S; Loureiro, Samanta O; Vuaden, Fernanda C; da Cunha, Aline A; Schmitz, Felipe; Kolling, Janaína; Savio, Luiz Eduardo B; Bogo, Maurício R; Bonan, Carla D; Netto, Carlos A; Wyse, Angela T S

    2014-10-01

    Mild hyperhomocysteinemia is considered to be a risk factor for cerebral and cardiovascular disorders and can be modeled in experimental rats. Inflammation has been implicated in the toxic effects of homocysteine. Cholinergic signaling controls cytokine production and inflammation through the "cholinergic anti-inflammatory pathway," and brain acetylcholinesterase activity plays a role in this regulation. The aim of this present study is to investigate the effect of mild chronic hyperhomocysteinemia on proinflammatory cytokine levels in the brain, heart, and serum of rats. Activity, immunocontent, and gene expression of acetylcholinesterase in the brain and butyrylcholinesterase activity in serum were also evaluated. Mild hyperhomocysteinemia was induced in Wistar rats by homocysteine administration (0.03 μmol/g of body weight) twice a day, from the 30th to the 60th days of life. Controls received saline in the same volumes. Results demonstrated an increase in tumor necrosis factor-alpha (TNF-α), interleukin-1β (IL-1β), interleukin-6 (IL-6), and the chemokine monocyte chemotactic protein-1 (MCP-1) in the hippocampus, as well as an increase in IL-1β and IL-6 levels in cerebral cortex. Acetylcholinesterase activity was increased in rats subjected to mild hyperhomocysteinemia in both cerebral structures tested; the immunocontent of this enzyme was also increased in the cerebral cortex and decreased in the hippocampus. Levels of acetylcholinesterase mRNA transcripts were not altered. Peripherally, homocysteine increased TNF-α, IL-6, and MCP-1 levels in the heart and IL-6 levels in serum. Taken altogether, these findings suggest that homocysteine promotes an inflammatory status that can contribute, at least in part, to neuronal and cardiovascular dysfunctions observed in mild hyperhomocysteinemia.

  8. The proinflammatory cytokine interleukin-18 alters multiple signaling pathways to inhibit natural killer cell death

    USGS Publications Warehouse

    Hodge, D.L.; Subleski, J.J.; Reynolds, D.A.; Buschman, M.D.; Schill, W.B.; Burkett, M.W.; Malyguine, A.M.; Young, H.A.

    2006-01-01

    The proinflammatory cytokine, interleukin-18 (IL-18), is a natural killer (NK) cell activator that induces NK cell cytotoxicity and interferon-?? (IFN-??) expression. In this report, we define a novel role for IL-18 as an NK cell protective agent. Specifically, IL-18 prevents NK cell death initiated by different and distinct stress mechanisms. IL-18 reduces NK cell self-destruction during NK-targeted cell killing, and in the presence of staurosporin, a potent apoptotic inducer, IL-18 reduces caspase-3 activity. The critical regulatory step in this process is downstream of the mitochondrion and involves reduced cleavage and activation of caspase-9 and caspase-3. The ability of IL-18 to regulate cell survival is not limited to a caspase death pathway in that IL-18 augments tumor necrosis factor (TNF) signaling, resulting in increased and prolonged mRNA expression of c-apoptosis inhibitor 2 (cIAP2), a prosurvival factor and caspase-3 inhibitor, and TNF receptor-associated factor 1 (TRAF1), a prosurvival protein. The cumulative effects of IL-18 define a novel role for this cytokine as a molecular survival switch that functions to both decrease cell death through inhibition of the mitochondrial apoptotic pathway and enhance TNF induction of prosurvival factors. ?? Mary Ann Liebert, Inc.

  9. Diclofenac enhances proinflammatory cytokine-induced nitric oxide production through NF-{kappa}B signaling in cultured astrocytes

    SciTech Connect

    Kakita, Hiroki; Aoyama, Mineyoshi Hussein, Mohamed Hamed; Kato, Shin; Suzuki, Satoshi; Ito, Tetsuya; Togari, Hajime; Asai, Kiyofumi

    2009-07-01

    Recently, the number of reports of encephalitis/encephalopathy associated with influenza virus has increased. In addition, the use of a non-steroidal anti-inflammatory drug, diclofenac sodium (DCF), is associated with a significant increase in the mortality rate of influenza-associated encephalopathy. Activated astrocytes are a source of nitric oxide (NO), which is largely produced by inducible NO synthase (iNOS) in response to proinflammatory cytokines. Therefore, we investigated whether DCF enhances nitric oxide production in astrocytes stimulated with proinflammatory cytokines. We stimulated cultured rat astrocytes with three cytokines, interleukin-1{beta}, tumor necrosis factor-{alpha} and interferon-{gamma}, and then treated the astrocytes with DCF or acetaminophen (N-acetyl-p-aminophenol: APAP). iNOS and NO production in astrocyte cultures were induced by proinflammatory cytokines. The addition of DCF augmented NO production, but the addition of APAP did not. NF-{kappa}B inhibitors SN50 and MG132 inhibited iNOS gene expression in cytokine-stimulated astrocytes with or without DCF. Similarly, NF-{kappa}B p65 Stealth small interfering RNA suppressed iNOS gene expression in cytokine-stimulated astrocytes with or without DCF. LDH activity and DAPI staining showed that DCF induces cell damage in cytokine-stimulated astrocytes. An iNOS inhibitor, L-NMMA, inhibited the cytokine- and DCF-induced cell damage. In conclusion, this study demonstrates that iNOS and NO are induced in astrocyte cultures by proinflammatory cytokines. Addition of DCF further augments NO production. This effect is mediated via NF-{kappa}B signaling and leads to cell damage. The enhancement of DCF on NO production may explain the significant increase in the mortality rate of influenza-associated encephalopathy in patients treated with DCF.

  10. Alpha/Beta Interferon Receptor Signaling Amplifies Early Proinflammatory Cytokine Production in the Lung during Respiratory Syncytial Virus Infection

    PubMed Central

    Goritzka, Michelle; Durant, Lydia R.; Pereira, Catherine; Salek-Ardakani, Samira; Openshaw, Peter J. M.

    2014-01-01

    ABSTRACT Type I interferons (IFNs) are produced early upon virus infection and signal through the alpha/beta interferon (IFN-α/β) receptor (IFNAR) to induce genes that encode proteins important for limiting viral replication and directing immune responses. To investigate the extent to which type I IFNs play a role in the local regulation of inflammation in the airways, we examined their importance in early lung responses to infection with respiratory syncytial virus (RSV). IFNAR1-deficient (IFNAR1−/−) mice displayed increased lung viral load and weight loss during RSV infection. As expected, expression of IFN-inducible genes was markedly reduced in the lungs of IFNAR1−/− mice. Surprisingly, we found that the levels of proinflammatory cytokines and chemokines in the lungs of RSV-infected mice were also greatly reduced in the absence of IFNAR signaling. Furthermore, low levels of proinflammatory cytokines were also detected in the lungs of IFNAR1−/− mice challenged with noninfectious innate immune stimuli such as selected Toll-like receptor (TLR) agonists. Finally, recombinant IFN-α was sufficient to potentiate the production of inflammatory mediators in the lungs of wild-type mice challenged with innate immune stimuli. Thus, in addition to its well-known role in antiviral resistance, type I IFN receptor signaling acts as a central driver of early proinflammatory responses in the lung. Inhibiting the effects of type I IFNs may therefore be useful in dampening inflammation in lung diseases characterized by enhanced inflammatory cytokine production. IMPORTANCE The initial response to viral infection is characterized by the production of interferons (IFNs). One group of IFNs, the type I IFNs, are produced early upon virus infection and signal through the IFN-α/β receptor (IFNAR) to induce proteins important for limiting viral replication and directing immune responses. Here we examined the importance of type I IFNs in early responses to respiratory

  11. Identification of IL-23p19 as an endothelial proinflammatory peptide that promotes gp130-STAT3 signaling.

    PubMed

    Espígol-Frigolé, Georgina; Planas-Rigol, Ester; Ohnuki, Hidetaka; Salvucci, Ombretta; Kwak, Hyeongil; Ravichandran, Sarangan; Luke, Brian; Cid, Maria C; Tosato, Giovanna

    2016-03-15

    Interleukin-23 (IL-23), a heterodimeric cytokine composed of the unique p19 peptide (IL-23p19) and a peptide called IL-12p40, which is shared with IL-12, is implicated in Crohn's disease, rheumatoid arthritis, psoriasis, and other immune-mediated inflammatory diseases. Endothelial cells produce the IL-23p19 peptide in the absence of the IL-12p40 chain and thus do not make heterodimeric IL-23. We found that intercellular IL-23p19 increased the cell surface abundances of intercellular adhesion molecule-1 (ICAM-1) and vascular cell adhesion molecule-1 (VCAM-1) on endothelial cells, which enhanced the attachment of leukocytes and increased their transendothelial migration. Intracellular p19 associated with the cytokine receptor subunit gp130 and stimulated the gp130-dependent activation of signal transducer and activator of transcription 3 (STAT3) signaling. Proinflammatory factors promoted the generation of IL-23p19 in endothelial cells. The adventitial capillaries of inflamed temporal arteries in patients with giant-cell arteritis (GCA) had endothelial p19 protein associated with gp130, but did not contain the IL-12p40 chain. Because adventitial capillaries are essential for the entry of inflammatory cells into arterial walls, these data suggest that p19 may contribute to GCA disease and could represent a therapeutic target. Our results provide evidence that IL-23p19 is a previously unrecognized endothelial proinflammatory peptide that promotes leukocyte transendothelial migration, advancing our current understanding of the complexities of inflammatory responses.

  12. OSCAR-collagen signaling in monocytes plays a proinflammatory role and may contribute to the pathogenesis of rheumatoid arthritis.

    PubMed

    Schultz, Heidi S; Guo, Li; Keller, Pernille; Fleetwood, Andrew J; Sun, Mingyi; Guo, Wei; Ma, Chunyan; Hamilton, John A; Bjørkdahl, Olle; Berchtold, Martin W; Panina, Svetlana

    2016-04-01

    Osteoclast-associated receptor (OSCAR) is an activating receptor expressed by human myeloid cells. Collagen type I (ColI) and collagen type II (ColII) serve as ligands for OSCAR. OSCAR-collagen interaction stimulates RANK-dependent osteoclastogenesis. We have recently reported that OSCAR promotes functional maturation of monocyte-derived dendritic cells. OSCAR is upregulated on monocytes from rheumatoid arthritis (RA) patients with active disease, and these monocytes show an increased proosteoclastogenic potential. In the current study, we have addressed a functional role for an OSCAR-collagen interaction on monocytes. We show that OSCAR-ColII signaling promoted the survival of monocytes. Moreover, ColII stimulated the release of proinflammatory cytokines by monocytes from healthy donors, which could be completely blocked by an anti-OSCAR monoclonal antibody. Mononuclear cells from the synovial fluid of RA patients plated on ColII secreted TNF-α and IL-8 in an OSCAR-dependent manner. Global RNA profiling showed that components of multiple signaling pathways relevant to RA pathogenesis are regulated at the transcriptional level by OSCAR in monocytes. Thus, OSCAR can play a proinflammatory role in monocyte-derived cells and may contribute crucially on multiple levels to RA pathogenesis.

  13. Increased hydrophobicity in Malassezia species correlates with increased proinflammatory cytokine expression in human keratinocytes.

    PubMed

    Akaza, Narifumi; Akamatsu, Hirohiko; Takeoka, Shiori; Mizutani, Hiroshi; Nakata, Satoru; Matsunaga, Kayoko

    2012-11-01

    Malassezia cells stimulate cytokine production by keratinocytes, although this ability differs among Malassezia species for unknown reasons. The aim of this study was to clarify the factors determining the ability to induce cytokine production by human keratinocytes in response to Malassezia species. M. furfur NBRC 0656, M. sympodialis CBS 7222, M. dermatis JCM 11348, M. globosa CBS 7966, M. restricta CBS 7877, and three strains each of M. globosa, M. restricta, M. dermatis, M. sympodialis, and M. furfur maintained under various culture conditions were used. Normal human epidermal keratinocytes (NHEKs) (1 × 10(5) cells) and the Malassezia species (1 × 10(6) cells) were co-cultured, and IL-1α, IL-6, and IL-8 mRNA levels were determined. Moreover, the hydrophobicity and β-1,3-glucan expression at the surface of Malassezia cells were analyzed. The ability of Malassezia cells to trigger the mRNA expression of proinflammatory cytokines in NHEKs differed with the species and conditions and was dependent upon the hydrophobicity of Malassezia cells not β-1,3-glucan expression.

  14. Nucleoside reverse transcriptase inhibitors (NRTIs) induce proinflammatory cytokines in the CNS via Wnt5a signaling.

    PubMed

    Wu, Ting; Zhang, Juan; Geng, Mingxing; Tang, Shao-Jun; Zhang, Wenping; Shu, Jianhong

    2017-06-23

    HAART is very effective in suppressing HIV-1 replication in patients. However, patients staying on long-term HAART still develop various HIV-associated neurological disorders, even when the viral load is low. The underlying pathogenic mechanisms are largely unknown. Emerging evidence implicated that persistent neuroinflammation plays an important role in NeuroAIDS. Although residual virus or viral proteins are commonly thought as the causal factors, we are interested in the alternative possibility that HAART critically contributes to the neuroinflammation in the central nervous system (CNS). To test this hypothesis, we have determined the effect of NRTIs on the expression of proinflammatory cytokines in the various CNS regions. Mice (C57Bl/6) were administered with AZT (Zidovudine 100 mg/kg/day), 3TC (Lamivudine 50 mg/kg/day) or D4T (Stavudine 10 mg/kg/day) for 5 days, and cortices, hippocampi and spinal cords were collected for immunoblotting. Our results showed that NRTI administration up-regulated cytokines, including IL-1β, TNF-α and IL-6 in various CNS regions. In addition, we found that NRTIs also up-regulated Wnt5a protein. Importantly, BOX5 attenuated NRTI-induced cytokine up-regulation. These results together suggest that NRTIs up-regulate proinflammatory cytokines via a Wnt5a signaling-dependent mechanism. Our findings may help understand the potential pathogenic mechanisms of HAART-associated NeuroAIDS and design effective adjuvants.

  15. SAA drives proinflammatory heterotypic macrophage differentiation in the lung via CSF-1R-dependent signaling

    PubMed Central

    Anthony, Desiree; McQualter, Jonathan L.; Bishara, Maria; Lim, Ee X.; Yatmaz, Selcuk; Seow, Huei Jiunn; Hansen, Michelle; Thompson, Michelle; Hamilton, John A.; Irving, Louis B.; Levy, Bruce D.; Vlahos, Ross; Anderson, Gary P.; Bozinovski, Steven

    2014-01-01

    Serum amyloid A (SAA) is expressed locally in chronic inflammatory conditions such as chronic obstructive pulmonary disease (COPD), where macrophages that do not accord with the classic M1/M2 paradigm also accumulate. In this study, the role of SAA in regulating macrophage differentiation was investigated in vitro using human blood monocytes from healthy subjects and patients with COPD and in vivo using an airway SAA challenge model in BALB/c mice. Differentiation of human monocytes with SAA stimulated the proinflammatory monokines IL-6 and IL-1β concurrently with the M2 markers CD163 and IL-10. Furthermore, SAA-differentiated macrophages stimulated with lipopolysaccharide (LPS) expressed markedly higher levels of IL-6 and IL-1β. The ALX/FPR2 antagonist WRW4 reduced IL-6 and IL-1β expression but did not significantly inhibit phagocytic and efferocytic activity. In vivo, SAA administration induced the development of a CD11chighCD11bhigh macrophage population that generated higher levels of IL-6, IL-1β, and G-CSF following ex vivo LPS challenge. Blocking CSF-1R signaling effectively reduced the number of CD11chighCD11bhigh macrophages by 71% and also markedly inhibited neutrophilic inflammation by 80%. In conclusion, our findings suggest that SAA can promote a distinct CD11chighCD11bhigh macrophage phenotype, and targeting this population may provide a novel approach to treating chronic inflammatory conditions associated with persistent SAA expression.—Anthony, D., McQualter, J. L., Bishara, M., Lim, E. X., Yatmaz, S., Seow, H. J., Hansen, M., Thompson, M., Hamilton, J. A., Irving, L. B., Levy, B. D., Vlahos, R., Anderson, G. P., Bozinovski, S. SAA drives proinflammatory heterotypic macrophage differentiation in the lung via CSF-1R-dependent signaling. PMID:24846388

  16. Differential pro-inflammatory responses of TNF-α receptors (TNFR1 and TNFR2) on LOX-1 signalling.

    PubMed

    Arjuman, Albina; Chandra, Nimai C

    2015-06-01

    TNF-α potently induces LOX-1 expression in THP-1 macrophages at concentrations between 1.25-50 ng/mL. The interplay between the two TNF receptors (TNFR1 and TNFR2) was apparent in the expression pattern of LOX-1 in response to TNF-α. Interestingly, R1 signal abrogation depleted both TNFR2 as well as LOX-1 transcript expression, suggesting that TNFR1 holds priority in the relative signaling mechanism between TNFR1 and TNFR2. TNF-α was also found to abrogate the oxidized-LDL (ox-LDL) mediated increase in intracellular pool of NO, a known downstream intermediate of LOX-1 pro-inflammatory signaling cascade. At the level of ox-LDL clearance, TNF-α inhibited the uptake (scavenging) of ox-LDL via LOX-1. Our study demonstrates the ability of TNF-α to enhance the signaling propensity of LOX-1 by increasing its expression and inhibiting its scavenging property.

  17. Increased feelings with increased body signals

    PubMed Central

    Vianna, Eduardo P. M.; Weinstock, Joel; Elliott, David; Summers, Robert; Tranel, Daniel

    2006-01-01

    Since the beginning of psychology as a scientific endeavour, the question of whether the body plays a role in how a person experiences emotion has been the centre of emotion research. Patients with structural gastrointestinal disorders, such as Crohn's disease, provide an intriguing opportunity to study the influence of body signals on emotions and feelings. In the present study, emotionally salient films were presented to participants with Crohn's disease in either the active state (Crohn's-active, CA) or silent state (Crohn's-silent, CS), and to normal comparison (NC) participants. We hypothesized that CA participants would have increased feelings, compared with CS and NC participants, when viewing emotional films designed to elicit happiness, disgust, sadness and fear. Gastric myoelectrical activity (electrogastrogram, or EGG) was measured during the films, and after each film was presented, participants rated emotion intensity (arousal) and pleasantness (valence). All groups labelled the emotions similarly. In support of the hypothesis, CA participants showed an increase in subjective arousal for negative emotions compared with CS and NC participants. The CA participants also showed increased EGG during emotional film viewing, as well as a strong positive correlation of EGG with arousal ratings. Together, these findings can be taken as evidence that aberrant feedback from the gastrointestinal system up-regulates the intensity of feelings of negative emotions. PMID:18985099

  18. Proinflammatory signal suppresses proliferation and shifts macrophage metabolism from Myc-dependent to HIF1α-dependent.

    PubMed

    Liu, Lingling; Lu, Yun; Martinez, Jennifer; Bi, Yujing; Lian, Gaojian; Wang, Tingting; Milasta, Sandra; Wang, Jian; Yang, Mao; Liu, Guangwei; Green, Douglas R; Wang, Ruoning

    2016-02-09

    As a phenotypically plastic cellular population, macrophages change their physiology in response to environmental signals. Emerging evidence suggests that macrophages are capable of tightly coordinating their metabolic programs to adjust their immunological and bioenergetic functional properties, as needed. Upon mitogenic stimulation, quiescent macrophages enter the cell cycle, increasing their bioenergetic and biosynthetic activity to meet the demands of cell growth. Proinflammatory stimulation, however, suppresses cell proliferation, while maintaining a heightened metabolic activity imposed by the production of bactericidal factors. Here, we report that the mitogenic stimulus, colony-stimulating factor 1 (CSF-1), engages a myelocytomatosis viral oncogen (Myc)-dependent transcriptional program that is responsible for cell cycle entry and the up-regulation of glucose and glutamine catabolism in bone marrow-derived macrophages (BMDMs). However, the proinflammatory stimulus, lipopolysaccharide (LPS), suppresses Myc expression and cell proliferation and engages a hypoxia-inducible factor alpha (HIF1α)-dependent transcriptional program that is responsible for heightened glycolysis. The acute deletion of Myc or HIF1α selectively impaired the CSF-1- or LPS-driven metabolic activities in BMDM, respectively. Finally, inhibition of glycolysis by 2-deoxyglucose (2-DG) or genetic deletion of HIF1α suppressed LPS-induced inflammation in vivo. Our studies indicate that a switch from a Myc-dependent to a HIF1α-dependent transcriptional program may regulate the robust bioenergetic support for an inflammatory response, while sparing Myc-dependent proliferation.

  19. CD54-Mediated Interaction with Pro-inflammatory Macrophages Increases the Immunosuppressive Function of Human Mesenchymal Stromal Cells.

    PubMed

    Espagnolle, Nicolas; Balguerie, Adélie; Arnaud, Emmanuelle; Sensebé, Luc; Varin, Audrey

    2017-04-11

    Mesenchymal stromal cells (MSCs) sense and modulate inflammation and represent potential clinical treatment for immune disorders. However, many details of the bidirectional interaction of MSCs and the innate immune compartment are still unsolved. Here we describe an unconventional but functional interaction between pro-inflammatory classically activated macrophages (M1MΦ) and MSCs, with CD54 playing a central role. CD54 was upregulated and enriched specifically at the contact area between M1MФ and MSCs. Moreover, the specific interaction induced calcium signaling and increased the immunosuppressive capacities of MSCs dependent on CD54 mediation. Our data demonstrate that MSCs can detect an inflammatory microenvironment via a direct and physical interaction with innate immune cells. This finding opens different perspectives for MSC-based cell therapy.

  20. Human SR-BII mediates SAA uptake and contributes to SAA pro-inflammatory signaling in vitro and in vivo.

    PubMed

    Baranova, Irina N; Souza, Ana C P; Bocharov, Alexander V; Vishnyakova, Tatyana G; Hu, Xuzhen; Vaisman, Boris L; Amar, Marcelo J; Chen, Zhigang; Remaley, Alan T; Patterson, Amy P; Yuen, Peter S T; Star, Robert A; Eggerman, Thomas L

    2017-01-01

    Serum amyloid A (SAA) is an acute phase protein with cytokine-like and chemotactic properties, that is markedly up-regulated during various inflammatory conditions. Several receptors, including FPRL-1, TLR2, TLR4, RAGE, class B scavenger receptors, SR-BI and CD36, have been identified as SAA receptors. This study provides new evidence that SR-BII, splice variant of SR-BI, could function as an SAA receptor mediating its uptake and pro-inflammatory signaling. The uptake of Alexa Fluor488 SAA was markedly (~3 fold) increased in hSR-BII-expressing HeLa cells when compared with mock-transfected cells. The levels of SAA-induced interleukin-8 secretion by hSR-BII-expressing HEK293 cells were also significantly (~3-3.5 fold) higher than those detected in control cells. Moderately enhanced levels of phosphorylation of all three mitogen-activated protein kinases, ERK1/2, and p38 and JNK, were observed in hSR-BII-expressing cells following SAA stimulation when compared with control wild type cells. Transgenic mice with pLiv-11-directed liver/kidney overexpression of hSR-BI or hSR-BII were used to assess the in vivo role of each receptor in SAA-induced pro-inflammatory response in these organs. Six hours after intraperitoneal SAA injection both groups of transgenic mice demonstrated markedly higher (~2-5-fold) expression levels of inflammatory mediators in the liver and kidney compared to wild type mice. Histological examinations of hepatic and renal tissue from SAA-treated mice revealed moderate level of damage in the liver of both transgenic but not in the wild type mice. Activities of plasma transaminases, biomarkers of liver injury, were also moderately higher in hSR-B transgenic mice when compared to wild type mice. Our findings identify hSR-BII as a functional SAA receptor that mediates SAA uptake and contributes to its pro-inflammatory signaling via the MAPKs-mediated signaling pathways.

  1. Human SR-BII mediates SAA uptake and contributes to SAA pro-inflammatory signaling in vitro and in vivo

    PubMed Central

    Souza, Ana C. P.; Bocharov, Alexander V.; Vishnyakova, Tatyana G.; Hu, Xuzhen; Vaisman, Boris L.; Amar, Marcelo J.; Chen, Zhigang; Remaley, Alan T.; Patterson, Amy P.; Yuen, Peter S. T.; Star, Robert A.; Eggerman, Thomas L.

    2017-01-01

    Serum amyloid A (SAA) is an acute phase protein with cytokine-like and chemotactic properties, that is markedly up-regulated during various inflammatory conditions. Several receptors, including FPRL-1, TLR2, TLR4, RAGE, class B scavenger receptors, SR-BI and CD36, have been identified as SAA receptors. This study provides new evidence that SR-BII, splice variant of SR-BI, could function as an SAA receptor mediating its uptake and pro-inflammatory signaling. The uptake of Alexa Fluor488 SAA was markedly (~3 fold) increased in hSR-BII-expressing HeLa cells when compared with mock-transfected cells. The levels of SAA-induced interleukin-8 secretion by hSR-BII-expressing HEK293 cells were also significantly (~3–3.5 fold) higher than those detected in control cells. Moderately enhanced levels of phosphorylation of all three mitogen-activated protein kinases, ERK1/2, and p38 and JNK, were observed in hSR-BII-expressing cells following SAA stimulation when compared with control wild type cells. Transgenic mice with pLiv-11-directed liver/kidney overexpression of hSR-BI or hSR-BII were used to assess the in vivo role of each receptor in SAA-induced pro-inflammatory response in these organs. Six hours after intraperitoneal SAA injection both groups of transgenic mice demonstrated markedly higher (~2-5-fold) expression levels of inflammatory mediators in the liver and kidney compared to wild type mice. Histological examinations of hepatic and renal tissue from SAA-treated mice revealed moderate level of damage in the liver of both transgenic but not in the wild type mice. Activities of plasma transaminases, biomarkers of liver injury, were also moderately higher in hSR-B transgenic mice when compared to wild type mice. Our findings identify hSR-BII as a functional SAA receptor that mediates SAA uptake and contributes to its pro-inflammatory signaling via the MAPKs-mediated signaling pathways. PMID:28423002

  2. Hedgehog Signaling Non-Canonical Activated by Pro-Inflammatory Cytokines in Pancreatic Ductal Adenocarcinoma

    PubMed Central

    Wang, Yuqiong; Jin, Gang; Li, Quanjiang; Wang, Zhiping; Hu, Weimin; Li, Ping; Li, Shude; Wu, Hongyu; Kong, Xiangyu; Gao, Jun; Li, Zhaoshen

    2016-01-01

    Hedgehog(HH) pathway is found to be activated through a manner of canonical, or the non-canonical HH pathways. Distinct hyperplasia stroma around tumor cells is supposed to express pro-inflammatory cytokines abundantly, such as tumor necrosis factor-α (TNF-α) and interleukin-1β (IL-1β), etc. in pancreatic ductal adenocarcinoma (PDAC) tissues. In this study we observed the effects of TNF-α and IL-1β on HH pathway activation in PDAC cells, and explored their activation manners. Our results showed that pro-inflammatory cytokines, TNF-α and IL-1β, could up-regulate the expression of GLI1 gene, increase its nuclear protein expression and promote malignant cell behaviors including migration, invasion, epithelial-mesenchymal transition (EMT) and drug resistance as well. Moreover, GLI1 promoter-reporter assay in combination with blocking either NF-κB or Smoothened (SMO) suggested that TNF-α and IL-1β could transcriptionally up-regulate expression of GLI1 completely via NF-κB, whereas ablation of SMO could not completely attenuate the regulation effects of TNF-α and IL-1β on GLI1 expression. Collectively, our results indicated that TNF-α and IL-1β in hyperplasia stroma can promote the PDAC cell development by activating HH pathway, through both the canonical and non-canonical HH activation ways. PMID:27877222

  3. High Thyroid-stimulating Hormone Levels Increase Proinflammatory and Cardiovascular Markers in Patients with Extreme Obesity.

    PubMed

    Gómez-Zamudio, Jaime Héctor; Mendoza-Zubieta, Victoria; Ferreira-Hermosillo, Aldo; Molina-Ayala, Marío Antonio; Valladares-Sálgado, Adán; Suárez-Sánchez, Fernando; de Jesús Peralta-Romero, Jose; Cruz, Miguel

    2016-08-01

    Obesity is an important health problem worldwide and many studies have suggested a relationship between obesity and thyroid function, with controversial results. Interestingly, high TSH levels have been involved with the presence of inflammatory state and risk for developing cardiovascular diseases in hypothyroid and obese patients. The aim in this work was to determine the prevalence of hypothyroidism in patients with extreme obesity and to determine whether their TSH levels were related to increased serum levels of inflammatory and cardiovascular markers. A cross-sectional study in 101 patients with extreme obesity (BMI ≥40) was performed. Anthropometric (weight, height and waist circumference) and biochemical (fasting glucose, glycosylated hemoglobin, triglycerides, total cholesterol, LDL-C, HDL-C and insulin) parameters were measured. TSH and FT4 levels as well as clinical exploration for diagnosis of hypothyroidism were carried out. Serum concentration of IL-10, IL-6, adiponectin, resistin, leptin, ICAM-1, VCAM-1 and E-selectin were determined. A high prevalence for diabetes (37.6%), prediabetes (50.5%), dyslipidemia (74.3%), hypertension (61.4%) and hypothyroidism (48.5%) was observed in patients with extreme obesity. The presence of hypothyroidism increased serum concentration of proinflammatory cytokines IL-6 and leptin and decreased the antiinflammatory cytokine adiponectin. In addition, serum TSH levels showed a correlation for waist circumference, weight, BMI, A1c, insulin, IL-6, leptin, ICAM-1 and E-selectin. There is a high prevalence for hypothyroidism in patients with extreme obesity. High levels of TSH contribute to elevate proinflammatory and cardiovascular risk markers, increasing the risk for development of cardiovascular diseases. Copyright © 2016 IMSS. Published by Elsevier Inc. All rights reserved.

  4. Glycine treatment decreases proinflammatory cytokines and increases interferon-gamma in patients with type 2 diabetes.

    PubMed

    Cruz, M; Maldonado-Bernal, C; Mondragón-Gonzalez, R; Sanchez-Barrera, R; Wacher, N H; Carvajal-Sandoval, G; Kumate, J

    2008-08-01

    Amino acids have been shown to stimulate insulin secretion and decrease glycated hemoglobin (A1C) in patients with Type 2 diabetes. In vitro, glycine reduces tumor necrosis factor (TNF)-alpha secretion and increases interleukin-10 secretion in human monocytes stimulated with lipopolysaccharide. The aim of this study was to determine whether glycine modifies the proinflammatory profiles of patients with Type 2 diabetes. Seventy-four patients, with Type 2 diabetes were enrolled in the study. The mean age was 58.5 yr, average age of diagnosis was 5 yr, the mean body mass index was 28.5 kg/m2, the mean fasting glucose level was 175.5 mg/dl and the mean A1C level was 8%. They were allocated to one of two treatments, 5 g/d glycine or 5 g/d placebo, po tid, for 3 months. A1C levels of patients given glycine were significantly lower after 3 months of treatment than those of the placebo group. A significant reduction in TNF-receptor I levels was observed in patients given glycine compared with placebo. There was a decrease of 38% in the interferon (IFN)-gamma level of the group treated with placebo, whereas that of the group treated with glycine increased up to 43%. These data showed that patients treated with glycine had a significant decrease in A1C and in proinflammatory cytokines and also an important increase of IFN-gamma. Treatment with glycine is likely to have a beneficial effect on innate and adaptive immune responses and may help prevent tissue damage caused by chronic inflammation in patients with Type 2 diabetes.

  5. TCR signal strength controls thymic differentiation of discrete proinflammatory γδ T cell subsets

    PubMed Central

    Muñoz-Ruiz, Miguel; Ribot, Julie C.; Grosso, Ana R.; Gonçalves-Sousa, Natacha; Pamplona, Ana; Pennington, Daniel J.; Regueiro, José R.

    2016-01-01

    The murine thymus produces discrete γδ T cell subsets making either interferon-γ (IFN--γ) or interleukin 17 (IL-17), but the role of the TCR in this developmental process remains controversial. Here we show that mice haploinsufficient for both Cd3g and Cd3d (CD3DH, for CD3 double haploinsufficient) have reduced TCR expression and signaling strength selectively on γδ T cells. CD3DH mice had normal numbers and phenotype of αβ thymocyte subsets but impaired differentiation of fetal Vγ6+ (but not Vγ4+) IL-17-producing γδ T cells and a marked depletion of IFN-γ-producing CD122+ NK1.1+ γδ T cells throughout ontogeny. Adult CD3DH mice showed reduced peripheral IFN-γ+ γδ T cells and were resistant to experimental cerebral malaria. Thus, TCR signal strength within specific thymic developmental windows is a major determinant of the generation of proinflammatory γδ T cell subsets and their impact on pathophysiology. PMID:27043412

  6. Parenteral nutrition in short bowel syndrome patients, regardless of its duration, increases serum proinflammatory cytokines.

    PubMed

    Bizari, Letícia; da Silva Santos, Andressa Feijó; Foss, Norma Tiraboschi; Marchini, Júlio Sérgio; Suen, Vivian Marques Miguel

    2016-07-01

    Short bowel syndrome is a severe malabsorption disorder, and prolonged parenteral nutrition is essential for survival in some cases. Among the undesirable effects of long-term parenteral nutrition is an increase in proinflammatory cytokines. The aim of the present study was to measure the serum levels of interleukin-6, interleukin-10, tumor necrosis factor alpha, and transforming growth factor beta, in patients with short bowel syndrome on cyclic parenteral nutrition and patients who had previously received but no longer require parenteral nutrition. The study was cross-sectional and observational. Three groups were studied as follows: Parenteral nutrition group, 9 patients with short bowel syndrome that receive cyclic parenteral nutrition; Oral nutrition group, 10 patients with the same syndrome who had been weaned off parenteral nutrition for at least 1 year prior to the study; Control group, 13 healthy adults, matched for age and sex to parenteral and oral groups. The following data were collected: age, tobacco use, drug therapies, dietary intake, body weight, height, blood collection. All interleukins were significantly higher in the parenteral group compared with the control group as follows: interleukin-6: 22 ± 19 vs 1.5 ± 1.4 pg/mL, P= .0002; transforming growth factor β: 854 ± 204 vs 607 ± 280 pg/mL, P= .04; interleukin-10: 8 ± 37 vs 0.6 ± 4, P= .03; tumor necrosis factor α: 20 ± 8 vs 8 ± 4 pg/mL, P< .0001. We concluded that parenteral nutrition in short bowel syndrome patients, regardless of its duration, increases serum proinflammatory cytokines.

  7. LAPTM5 protein is a positive regulator of proinflammatory signaling pathways in macrophages.

    PubMed

    Glowacka, Wioletta K; Alberts, Philipp; Ouchida, Rika; Wang, Ji-Yang; Rotin, Daniela

    2012-08-10

    LAPTM5 (lysosomal-associated protein transmembrane 5) is a protein that is preferentially expressed in immune cells, and it interacts with the Nedd4 family of ubiquitin ligases. Recent studies in T and B cells identified LAPTM5 as a negative regulator of T and B cell receptor levels at the plasma membrane. Here we investigated the function of LAPTM5 in macrophages. We demonstrate that expression of LAPTM5 is required for the secretion of proinflammatory cytokines in response to Toll-like receptor ligands. We also show that RAW264.7 cells knocked down for LAPTM5 or macrophages from LAPTM5(-/-) mice exhibit reduced activation of NF-κB and MAPK signaling pathways mediated by the TNF receptor, as well as multiple pattern recognition receptors in various cellular compartments. TNF stimulation of LAPTM5-deficient macrophages leads to reduced ubiquitination of RIP1 (receptor-interacting protein 1), suggesting a role for LAPTM5 at the receptor-proximate level. Interestingly, we find that macrophages from LAPTM5(-/-) mice display up-regulated levels of A20, a ubiquitin-editing enzyme responsible for deubiquitination of RIP1 and subsequent termination of NF-κB activation. Our studies thus indicate that, in contrast to its negative role in T and B cell activation, LAPTM5 acts as a positive modulator of inflammatory signaling pathways and hence cytokine secretion in macrophages. They also highlight a role for the endosomal/lysosomal system in regulating signaling via cytokine and pattern recognition receptors.

  8. LAPTM5 Protein Is a Positive Regulator of Proinflammatory Signaling Pathways in Macrophages*

    PubMed Central

    Glowacka, Wioletta K.; Alberts, Philipp; Ouchida, Rika; Wang, Ji-Yang; Rotin, Daniela

    2012-01-01

    LAPTM5 (lysosomal-associated protein transmembrane 5) is a protein that is preferentially expressed in immune cells, and it interacts with the Nedd4 family of ubiquitin ligases. Recent studies in T and B cells identified LAPTM5 as a negative regulator of T and B cell receptor levels at the plasma membrane. Here we investigated the function of LAPTM5 in macrophages. We demonstrate that expression of LAPTM5 is required for the secretion of proinflammatory cytokines in response to Toll-like receptor ligands. We also show that RAW264.7 cells knocked down for LAPTM5 or macrophages from LAPTM5−/− mice exhibit reduced activation of NF-κB and MAPK signaling pathways mediated by the TNF receptor, as well as multiple pattern recognition receptors in various cellular compartments. TNF stimulation of LAPTM5-deficient macrophages leads to reduced ubiquitination of RIP1 (receptor-interacting protein 1), suggesting a role for LAPTM5 at the receptor-proximate level. Interestingly, we find that macrophages from LAPTM5−/− mice display up-regulated levels of A20, a ubiquitin-editing enzyme responsible for deubiquitination of RIP1 and subsequent termination of NF-κB activation. Our studies thus indicate that, in contrast to its negative role in T and B cell activation, LAPTM5 acts as a positive modulator of inflammatory signaling pathways and hence cytokine secretion in macrophages. They also highlight a role for the endosomal/lysosomal system in regulating signaling via cytokine and pattern recognition receptors. PMID:22733818

  9. Modulation of proinflammatory NF-κB signaling by ectromelia virus in RAW 264.7 murine macrophages.

    PubMed

    Struzik, Justyna; Szulc-Dąbrowska, Lidia; Papiernik, Diana; Winnicka, Anna; Niemiałtowski, Marek

    2015-09-01

    Macrophages are antigen-presenting cells (APCs) that play a crucial role in the innate immune response and may be involved in both clearance and spread of viruses. Stimulation of macrophages via Toll-like receptors (TLRs) results in activation of nuclear factor κB (NF-κB) and synthesis of proinflammatory cytokines. In this work, we show modulation of proinflammatory NF-κB signaling by a member of the family Poxviridae, genus Orthopoxvirus--ectromelia virus (ECTV)--in RAW 264.7 murine macrophages. ECTV interfered with p65 NF-κB nuclear translocation induced by TLR ligands such as lipopolysaccharide (LPS) (TLR4), polyinosinic-polycytidylic acid (poly(I:C)) (TLR3) and diacylated lipopeptide Pam2CSK4 (TLR2/6). We observed that ECTV modulates phosphorylation of Ser32 of inhibitor of κB (IκBα) and Ser536 of p65. Interference of ECTV with TLR signaling pathways implied that proinflammatory cytokine synthesis was inhibited. Our studies provide new insights into the strategies of proinflammatory signaling modulation by orthopoxviruses during their replication cycle in immune cells. Understanding important immune interactions between viral pathogens and APCs might contribute to the identification of drug targets and the development of vaccines.

  10. LPS induces pro-inflammatory response in mastitis mice and mammary epithelial cells: Possible involvement of NF-κB signaling and OPN.

    PubMed

    Xiao, H-B; Wang, C-R; Liu, Z-K; Wang, J-Y

    2015-02-01

    Lipopolysaccharide (LPS) has pro-inflammatory properties. This study was conducted to determine whether the LPS induced pro-inflammatory response in a model of mastitis and in mouse mammary epithelial cells (MEC). To investigate the effects of LPS in vivo, 50 μL of a solution of LPS (20 ng/μL) were infused into the mammary glands of mice. To study the effects of LPS in vitro, MEC were exposed to LPS (20 μg/mL) for 24h. Activation of nuclear factor kB (NF-κB) and myeloperoxidase (MPO) were studied. Production of pro-inflammatory cytokines (interleukin-6 [IL-6], tumor necrosis factor-alpha [TNF-alpha], interleukin-1 beta [IL-1 beta]) and expression of osteopontin (OPN) were also evaluated. After LPS administration, route of NF-κB signaling is activated and the activity of MPO is increased. Furthermore, LPS increases the expression of OPN and production of TNF-alpha, IL-6 and IL-1 beta. Present results demonstrate that LPS induces a pro-inflammatory response in a murine model of mastitis and suggest the involvement of the NF-κB pathway and OPN. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

  11. Impaired macrophage autophagy increases the immune response in obese mice by promoting proinflammatory macrophage polarization

    PubMed Central

    Liu, Kun; Zhao, Enpeng; Ilyas, Ghulam; Lalazar, Gadi; Lin, Yu; Haseeb, Muhammad; Tanaka, Kathryn E; Czaja, Mark J

    2015-01-01

    Recent evidence that excessive lipid accumulation can decrease cellular levels of autophagy and that autophagy regulates immune responsiveness suggested that impaired macrophage autophagy may promote the increased innate immune activation that underlies obesity. Primary bone marrow-derived macrophages (BMDM) and peritoneal macrophages from high-fat diet (HFD)-fed mice had decreased levels of autophagic flux indicating a generalized impairment of macrophage autophagy in obese mice. To assess the effects of decreased macrophage autophagy on inflammation, mice with a Lyz2-Cre-mediated knockout of Atg5 in macrophages were fed a HFD and treated with low-dose lipopolysaccharide (LPS). Knockout mice developed systemic and hepatic inflammation with HFD feeding and LPS. This effect was liver specific as knockout mice did not have increased adipose tissue inflammation. The mechanism by which the loss of autophagy promoted inflammation was through the regulation of macrophage polarization. BMDM and Kupffer cells from knockout mice exhibited abnormalities in polarization with both increased proinflammatory M1 and decreased anti-inflammatory M2 polarization as determined by measures of genes and proteins. The heightened hepatic inflammatory response in HFD-fed, LPS-treated knockout mice led to liver injury without affecting steatosis. These findings demonstrate that autophagy has a critical regulatory function in macrophage polarization that downregulates inflammation. Defects in macrophage autophagy may underlie inflammatory disease states such as the decrease in macrophage autophagy with obesity that leads to hepatic inflammation and the progression to liver injury. PMID:25650776

  12. Impaired macrophage autophagy increases the immune response in obese mice by promoting proinflammatory macrophage polarization.

    PubMed

    Liu, Kun; Zhao, Enpeng; Ilyas, Ghulam; Lalazar, Gadi; Lin, Yu; Haseeb, Muhammad; Tanaka, Kathryn E; Czaja, Mark J

    2015-01-01

    Recent evidence that excessive lipid accumulation can decrease cellular levels of autophagy and that autophagy regulates immune responsiveness suggested that impaired macrophage autophagy may promote the increased innate immune activation that underlies obesity. Primary bone marrow-derived macrophages (BMDM) and peritoneal macrophages from high-fat diet (HFD)-fed mice had decreased levels of autophagic flux indicating a generalized impairment of macrophage autophagy in obese mice. To assess the effects of decreased macrophage autophagy on inflammation, mice with a Lyz2-Cre-mediated knockout of Atg5 in macrophages were fed a HFD and treated with low-dose lipopolysaccharide (LPS). Knockout mice developed systemic and hepatic inflammation with HFD feeding and LPS. This effect was liver specific as knockout mice did not have increased adipose tissue inflammation. The mechanism by which the loss of autophagy promoted inflammation was through the regulation of macrophage polarization. BMDM and Kupffer cells from knockout mice exhibited abnormalities in polarization with both increased proinflammatory M1 and decreased anti-inflammatory M2 polarization as determined by measures of genes and proteins. The heightened hepatic inflammatory response in HFD-fed, LPS-treated knockout mice led to liver injury without affecting steatosis. These findings demonstrate that autophagy has a critical regulatory function in macrophage polarization that downregulates inflammation. Defects in macrophage autophagy may underlie inflammatory disease states such as the decrease in macrophage autophagy with obesity that leads to hepatic inflammation and the progression to liver injury.

  13. Injury Induces Localized Airway Increases in Pro-Inflammatory Cytokines in Humans and Mice

    PubMed Central

    Jonker, Mark A.; Hermsen, Joshua L.; Gomez, F. Enrique; Sano, Yoshifumi

    2011-01-01

    Abstract Background Secretory immunoglobulin A (sIgA) increases in the airways of humans and mice after injury to protect against infection. The pro-inflammatory cytokines tumor necrosis factor (TNF)-α, interleukin (IL)-1β, and IL-6 are linked molecularly to sIgA production and secretion and are required for sIgA increases in the airway after injury in a mouse model. We investigated the injury effect on airway and serum concentrations to determine the source of the cytokines involved in the airway IgA response. Methods In the first experiment, TNF-α, IL-1β, and IL-6 concentrations in bronchoalveolar lavage (BAL) fluid and serum obtained from 11 ventilated trauma patients within 30 h of admission were compared with those in eight elective surgical patients. In the second experiment, male ICR mice received no injury (n = 7) or injury with sham celiotomy and neck incisions (n = 8) with sacrifice of all animals at 8 h for BAL fluid and serum cytokine measurements by enzyme-linked immunosorbent assay. Results Injured patients had significantly higher BAL fluid and serum TNF-α, IL-1β, and IL-6 concentrations, with greater increases in the BAL fluid than in the serum. Injured mice had significantly increased BAL fluid concentrations of TNF-α, IL-1β, and IL-6 without significant changes in serum TNF-α or IL-1β. Serum IL-6 increased significantly. Conclusions Injury significantly increases human and mouse airway TNF-α, IL-1β, and IL-6. Increases are greater in the airway than in serum, implying a local rather than a systemic stress response to injury. PMID:21166596

  14. Glycocalyx Degradation Induces a Proinflammatory Phenotype and Increased Leukocyte Adhesion in Cultured Endothelial Cells under Flow

    PubMed Central

    McDonald, Karli K.; Cooper, Scott; Danielzak, Lisa; Leask, Richard L.

    2016-01-01

    Leukocyte adhesion to the endothelium is an early step in the pathogenesis of atherosclerosis. Effective adhesion requires the binding of leukocytes to their cognate receptors on the surface of endothelial cells. The glycocalyx covers the surface of endothelial cells and is important in the mechanotransduction of shear stress. This study aimed to identify the molecular mechanisms underlying the role of the glycocalyx in leukocyte adhesion under flow. We performed experiments using 3-D cell culture models, exposing human abdominal aortic endothelial cells to steady laminar shear stress (10 dynes/cm2 for 24 hours). We found that with the enzymatic degradation of the glycocalyx, endothelial cells developed a proinflammatory phenotype when exposed to uniform steady shear stress leading to an increase in leukocyte adhesion. Our results show an up-regulation of ICAM-1 with degradation compared to non-degraded controls (3-fold increase, p<0.05) and we attribute this effect to a de-regulation in NF-κB activity in response to flow. These results suggest that the glycocalyx is not solely a physical barrier to adhesion but rather plays an important role in governing the phenotype of endothelial cells, a key determinant in leukocyte adhesion. We provide evidence for how the destabilization of this structure may be an early and defining feature in the initiation of atherosclerosis. PMID:27907146

  15. The pro-inflammatory cytokines IFNγ/TNFα increase chromogranin A-positive neuroendocrine cells in the colonic epithelium.

    PubMed

    Hernández-Trejo, José Antonio; Suárez-Pérez, Dimelza; Gutiérrez-Martínez, Itzel Zenidel; Fernandez-Vargas, Omar Eduardo; Serrano, Carolina; Candelario-Martínez, Aurora Antonia; Meraz-Ríos, Marco Antonio; Citalán-Madrid, Alí Francisco; Hernández-Ruíz, Marcela; Reyes-Maldonado, Elba; Valle-Rios, Ricardo; Feintuch-Unger, Jacobo H; Schnoor, Michael; Villegas-Sepúlveda, Nicolás; Medina-Contreras, Oscar; Nava, Porfirio

    2016-11-01

    The gastrointestinal tract is the largest hormone-producing organ in the body due to a specialized cell population called enteroendocrine cells (EECs). The number of EECs increases in the mucosa of inflammatory bowel disease patients; however, the mechanisms responsible for these changes remain unknown. Here, we show that the pro-inflammatory cytokines interferon γ (IFNγ) and tumor necrosis factor α (TNFα) or dextran sulfate sodium (DSS)-induced colitis increase the number of EECs producing chromogranin A (CgA) in the colonic mucosa of C57BL/6J mice. CgA-positive cells were non-proliferating cells enriched with inactive phosphatase and tensin homolog deleted on chromosome 10 (PTEN) and autophagy markers. Moreover, inhibition of Akt and autophagy prevented the increase in CgA-positive cells after IFNγ/TNFα treatment. Similarly, we observed that CgA-positive cells in the colonic mucosa of patients with colitis expressed Akt and autophagy markers. These findings suggest that Akt signaling and autophagy control differentiation of the intestinal EEC lineage during inflammation.

  16. Maternal BCG scar is associated with increased infant proinflammatory immune responses

    PubMed Central

    Mawa, Patrice Akusa; Webb, Emily L.; Filali-Mouhim, Abdelali; Nkurunungi, Gyaviira; Sekaly, Rafick-Pierre; Lule, Swaib Abubaker; Prentice, Sarah; Nash, Stephen; Dockrell, Hazel M.; Elliott, Alison M.; Cose, Stephen

    2017-01-01

    Maternal BCG scar had a stronger association with infant responses than maternal LTBI, with an increased proinflammatory immune profile. PMID:27914741

  17. Hepatitis C virus (HCV)-induced suppressor of cytokine signaling (SOCS) 3 regulates proinflammatory TNF-α responses.

    PubMed

    Collins, Aideen S; Ahmed, Suaad; Napoletano, Silvia; Schroeder, Martina; Johnston, James A; Hegarty, John E; O'Farrelly, Cliona; Stevenson, Nigel J

    2014-08-01

    TNF-α is a proinflammatory cytokine, dramatically elevated during pathogenic infection and often responsible for inflammation-induced disease pathology. SOCS proteins are inhibitors of cytokine signaling and regulators of inflammation. In this study, we found that both SOCS1 and SOCS3 were transiently induced by TNF-α and negatively regulate its NF-κB-mediated signal transduction. We discovered that PBMCs from HCV-infected patients have elevated endogenous SOCS3 expression but less TNF-α-mediated IκB degradation and proinflammatory cytokine production than healthy controls. HCV protein expression in Huh7 hepatocytes also induced SOCS3 and directly inhibited TNF-α-mediated IL-8 production. Furthermore, we found that SOCS3 associates with TRAF2 and inhibits TRAF2-mediated NF-κB promoter activity, suggesting a mechanism by which SOCS3 inhibits TNF-α-mediated signaling. These results demonstrate a role for SOCS3 in regulating proinflammatory TNF-α signal transduction and reveal a novel immune-modulatory mechanism by which HCV suppresses inflammatory responses in primary immune cells and hepatocytes, perhaps explaining mild pathology often associated with acute HCV infection.

  18. SAA drives proinflammatory heterotypic macrophage differentiation in the lung via CSF-1R-dependent signaling.

    PubMed

    Anthony, Desiree; McQualter, Jonathan L; Bishara, Maria; Lim, Ee X; Yatmaz, Selcuk; Seow, Huei Jiunn; Hansen, Michelle; Thompson, Michelle; Hamilton, John A; Irving, Louis B; Levy, Bruce D; Vlahos, Ross; Anderson, Gary P; Bozinovski, Steven

    2014-09-01

    Serum amyloid A (SAA) is expressed locally in chronic inflammatory conditions such as chronic obstructive pulmonary disease (COPD), where macrophages that do not accord with the classic M1/M2 paradigm also accumulate. In this study, the role of SAA in regulating macrophage differentiation was investigated in vitro using human blood monocytes from healthy subjects and patients with COPD and in vivo using an airway SAA challenge model in BALB/c mice. Differentiation of human monocytes with SAA stimulated the proinflammatory monokines IL-6 and IL-1β concurrently with the M2 markers CD163 and IL-10. Furthermore, SAA-differentiated macrophages stimulated with lipopolysaccharide (LPS) expressed markedly higher levels of IL-6 and IL-1β. The ALX/FPR2 antagonist WRW4 reduced IL-6 and IL-1β expression but did not significantly inhibit phagocytic and efferocytic activity. In vivo, SAA administration induced the development of a CD11c(high)CD11b(high) macrophage population that generated higher levels of IL-6, IL-1β, and G-CSF following ex vivo LPS challenge. Blocking CSF-1R signaling effectively reduced the number of CD11c(high)CD11b(high) macrophages by 71% and also markedly inhibited neutrophilic inflammation by 80%. In conclusion, our findings suggest that SAA can promote a distinct CD11c(high)CD11b(high) macrophage phenotype, and targeting this population may provide a novel approach to treating chronic inflammatory conditions associated with persistent SAA expression. © FASEB.

  19. High-Density Lipoproteins Exert Pro-inflammatory Effects on Macrophages via Passive Cholesterol Depletion and PKC-NF-κB/STAT1-IRF1 Signaling.

    PubMed

    van der Vorst, Emiel P C; Theodorou, Kosta; Wu, Yongzheng; Hoeksema, Marten A; Goossens, Pieter; Bursill, Christina A; Aliyev, Taghi; Huitema, Leonie F A; Tas, Sander W; Wolfs, Ine M J; Kuijpers, Marijke J E; Gijbels, Marion J; Schalkwijk, Casper G; Koonen, Debby P Y; Abdollahi-Roodsaz, Shahla; McDaniels, Kimberly; Wang, Chih-Chieh; Leitges, Michael; Lawrence, Toby; Plat, Jogchum; Van Eck, Miranda; Rye, Kerry-Anne; Touqui, Lhousseine; de Winther, Menno P J; Biessen, Erik A L; Donners, Marjo M P C

    2017-01-10

    Membrane cholesterol modulates a variety of cell signaling pathways and functions. While cholesterol depletion by high-density lipoproteins (HDLs) has potent anti-inflammatory effects in various cell types, its effects on inflammatory responses in macrophages remain elusive. Here we show overt pro-inflammatory effects of HDL-mediated passive cholesterol depletion and lipid raft disruption in murine and human primary macrophages in vitro. These pro-inflammatory effects were confirmed in vivo in peritoneal macrophages from apoA-I transgenic mice, which have elevated HDL levels. In line with these findings, the innate immune responses required for clearance of P. aeruginosa bacterial infection in lung were compromised in mice with low HDL levels. Expression analysis, ChIP-PCR, and combinatorial pharmacological and genetic intervention studies unveiled that both native and reconstituted HDL enhance Toll-like-receptor-induced signaling by activating a PKC-NF-κB/STAT1-IRF1 axis, leading to increased inflammatory cytokine expression. HDL's pro-inflammatory activity supports proper functioning of macrophage immune responses. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Xanomeline suppresses excessive pro-inflammatory cytokine responses through neural signal-mediated pathways and improves survival in lethal inflammation

    PubMed Central

    Rosas-Ballina, Mauricio; Ferrer, Sergio Valdés; Dancho, Meghan; Ochani, Mahendar; Katz, David; Cheng, Kai Fan; Olofsson, Peder S.; Chavan, Sangeeta S.; Al-Abed, Yousef; Tracey, Kevin J.; Pavlov, Valentin A.

    2014-01-01

    Inflammatory conditions characterized by excessive immune cell activation and cytokine release, are associated with bidirectional immune system-brain communication, underlying sickness behavior and other physiological responses. The vagus nerve has an important role in this communication by conveying sensory information to the brain, and brain-derived immunoregulatory signals that suppress peripheral cytokine levels and inflammation. Brain muscarinic acetylcholine receptor (mAChR)-mediated cholinergic signaling has been implicated in this regulation. However, the possibility of controlling inflammation by peripheral administration of centrally-acting mAChR agonists is unexplored. To provide insight we used the centrally-acting M1 mAChR agonist xanomeline, previously developed in the context of Alzheimer’s disease and schizophrenia. Intraperitoneal administration of xanomeline significantly suppressed serum and splenic TNF levels, alleviated sickness behavior, and increased survival during lethal murine endotoxemia. The anti-inflammatory effects of xanomeline were brain mAChR-mediated and required intact vagus nerve and splenic nerve signaling. The anti-inflammatory efficacy of xanomeline was retained for at least 20h, associated with alterations in splenic lymphocyte, and dendritic cell proportions, and decreased splenocyte responsiveness to endotoxin. These results highlight an important role of the M1 mAChR in a neural circuitry to spleen in which brain cholinergic activation lowers peripheral pro-inflammatory cytokines to levels favoring survival. The therapeutic efficacy of xanomeline was also manifested by significantly improved survival in preclinical settings of severe sepsis. These findings are of interest for strategizing novel therapeutic approaches in inflammatory diseases. PMID:25063706

  1. The oxytocin receptor antagonist, Atosiban, activates pro-inflammatory pathways in human amnion via G(αi) signalling.

    PubMed

    Kim, Sung Hye; MacIntyre, David A; Hanyaloglu, Aylin C; Blanks, Andrew M; Thornton, Steven; Bennett, Phillip R; Terzidou, Vasso

    2016-01-15

    Oxytocin (OT) plays an important role in the onset of human labour by stimulating uterine contractions and promoting prostaglandin/inflammatory cytokine synthesis in amnion via oxytocin receptor (OTR) coupling. The OTR-antagonist, Atosiban, is widely used as a tocolytic for the management of acute preterm labour. We found that in primary human amniocytes, Atosiban (10 μM) signals via PTX-sensitive Gαi to activate transcription factor NF-κB p65, ERK1/2, and p38 which subsequently drives upregulation of the prostaglandin synthesis enzymes, COX-2 and phospho-cPLA2 and excretion of prostaglandins (PGE2) (n = 6; p < 0.05, ANOVA). Moreover, Atosiban treatment increased expression and excretion of the inflammatory cytokines, IL-6 and CCL5. We also showed that OT-simulated activation of NF-κB, ERK1/2, and p38 and subsequent prostaglandin and inflammatory cytokine synthesis is via Gαi-2 and Gαi-3 but not Gαq, and is not inhibited by Atosiban. Activation or exacerbation of inflammation is not a desirable effect of tocolytics. Therefore therapeutic modulation of the OT/OTR system for clinical management of term/preterm labour should consider the effects of differential G-protein coupling of the OTR and the role of OT or selective OTR agonists/antagonists in activating proinflammatory pathways.

  2. P2Y6 Receptor-Mediated Proinflammatory Signaling in Human Bronchial Epithelia

    PubMed Central

    Hao, Yuan; Liang, Jocelyn F.; Chow, Alison W.; Cheung, Wing-tai; Ko, Wing-hung

    2014-01-01

    P2Y receptors are expressed in virtually all epithelia and are responsible for the control of fluid and electrolyte transport. In asthmatic inflammation, the bronchial epithelia are damaged by eosinophil-derived, highly toxic cationic proteins, such as major basic protein (MBP). Consequently, extracellular nucleotides are released into the extracellular space from airway epithelial cells, and act in an autocrine or paracrine fashion to regulate immune functions. Our data show damage to the human bronchial epithelial cell line, 16HBE14o-, by poly-L-arginine-induced UDP release into the extracellular medium. Activation of P2Y6 receptor by its natural ligand, UDP, or its specific agonist, MRS 2693, led to the production of two proinflammatory cytokines, interleukin (IL)-6 and IL-8. This may have resulted from increased IL-6 and IL-8 mRNA expression, and activation of p38 and ERK1/2 MAPK, and NF-κB pathways. Our previous study demonstrated that UDP stimulated transepithelial Cl− secretion via both Ca2+- and cAMP-dependent pathways in 16HBE14o- epithelia. This was further confirmed in this study by simultaneous imaging of Ca2+ and cAMP levels in single cells using the Fura-2 fluorescence technique and a FRET-based approach, respectively. Moreover, the P2Y6 receptor-mediated production of IL-6 and IL-8 was found to be dependent on Ca2+, but not the cAMP/PKA pathway. Together, these studies show that nucleotides released during the airway inflammatory processes will activate P2Y6 receptors, which will lead to further release of inflammatory cytokines. The secretion of cytokines and the formation of such “cytokine networks” play an important role in sustaining the airway inflammatory disease. PMID:25243587

  3. JAK2 Disease-Risk Variants Are Gain of Function and JAK Signaling Threshold Determines Innate Receptor-Induced Proinflammatory Cytokine Secretion in Macrophages.

    PubMed

    Hedl, Matija; Proctor, Deborah D; Abraham, Clara

    2016-11-01

    JAK2 genetic variants are associated with inflammatory bowel disease (IBD) and JAK inhibitors are being evaluated for therapy targeting immune-mediated diseases, including IBD. As JAK pathway-mediated cytokine regulation varies across cell types and stimulation conditions, we examined how JAK signaling and IBD-associated JAK2 variants regulate distinct acute and chronic microbial product exposure outcomes in human myeloid cells, consistent with the conditions of initial entry and ongoing intestinal tissue residence, respectively. Macrophages from controls and ulcerative colitis patients carrying the IBD-risk rs10758669 CC genotype showed increased JAK2 expression and nucleotide-binding oligomerization domain 2-induced JAK2 phosphorylation relative to AA carriers. Interestingly, the threshold of JAK2 expression and signaling determined pattern-recognition receptor (PRR)-induced outcomes; whereas anti-inflammatory cytokines progressively decreased with lower JAK2 expression, proinflammatory cytokines switched from decreased to increased secretion below a certain JAK2 expression threshold. Low JAK2-expressing rs10758669 AA macrophages were above this threshold; consequently, both PRR-induced pro- and anti-inflammatory cytokines were decreased. However, relative to rs10758669 CC risk carriers, AA carrier macrophages switched to increased nucleotide-binding oligomerization domain 2-induced proinflammatory cytokines at lower therapeutically used JAK inhibitor doses. Importantly, JAK inhibitors increased proinflammatory cytokines secreted by peripheral macrophages following chronic PRR stimulation and by human intestinal myeloid cells following exposure to intestinal pathogens. Mechanistically, the decreased response to and secretion of autocrine/paracrine IL-10, IL-4, IL-22 and thymic stromal lymphopoietin regulated these JAK-dependent outcomes in myeloid cells. Taken together, the JAK signaling threshold determines whether PRR-induced pro- and anti

  4. Vasculitic peripheral neuropathy induced by ischemia-reperfusion in the rat femoral artery involves activation of proinflammatory signaling pathway in the sciatic nerve.

    PubMed

    Chung, Chih-Yang; Chang, Yi-Wei; Huang, Chun-Jen; Wang, Po-Kai; Wan, Hung-Chieh; Lin, Yi-Ying; Kao, Ming-Chang

    2017-08-24

    Ischemia-reperfusion (IR) in the rat femoral artery has been proposed as an experimental model of vasculitic peripheral neuropathy (VPN) which presents neuropathic pain and peripheral nerve injury patterns observed clinically. This study investigates the involvement of the proinflammatory signaling pathway underlying the peripheral mechanisms of VPN. Male Sprague-Dawley rats were allocated to receive either a sham operation or IR. IR was induced by occluding the right femoral artery for 4h followed by reperfusion periods from 0 to 72h. The behavioral parameters were assessed at baseline as well as at days 1, 2 and 3 after reperfusion. The time-course analyses of proinflammatory mediators in the sciatic nerves were also performed on rats of the sham group or IR groups with reperfusion periods of 0, 2, 4, 24 and 72h, respectively. The behavioral data confirmed that this VPN model induced hindpaw mechano-allodynia and heat hyperalgesia as well as impaired hindpaw grip strength. The molecular data revealed that IR in the femoral artery activated the expression of nuclear factor-κB (NF-κB) in the sciatic nerve indicating a neuroinflammatory response. Moreover, IR in the femoral artery increased the expression of proinflammatory cytokines TNF-α and IL-1β in the sciatic nerve. This study elucidated the novel time-course expression profiles of NF-κB and proinflammatory cytokines in VPN induced by IR which may be involved in the development of neuropathic pain. Since NF-κB is a key element during neuroinflammation, strategies targeting the NF-κB signaling pathway may provide therapeutic potential against VPN induced by IR. Copyright © 2017 Elsevier B.V. All rights reserved.

  5. RUNX1c regulates hematopoietic differentiation of human pluripotent stem cells possibly in cooperation with pro-inflammatory signaling.

    PubMed

    Navarro-Montero, Oscar; Ayllon, Veronica; Lamolda, Mar; López-Onieva, Lourdes; Montes, Rosa; Bueno, Clara; Ng, Elizabeth; Guerrero-Carreno, Xiomara; Romero, Tamara; Romero-Moya, Damià; Stanley, Ed; Elefanty, Andrew; Ramos-Mejia, Verónica; Menendez, Pablo; Real, Pedro J

    2017-09-04

    Runx1 is a master hematopoietic transcription factor essential for hematopoietic stem cell (HSC) emergence. Runx1-deficient mice die during early embryogenesis due to the inability to establish definitive hematopoiesis. Here we have used hPSCs as model to study the role of RUNX1 in human embryonic hematopoiesis. Although the three RUNX1 isoforms a, b and c were induced in CD45+ hematopoietic cells, RUNX1c was the only isoform induced in hemato-endothelial progenitors (HEPs)/hemogenic endothelium. Constitutive expression of RUNX1c in hESCs enhanced the appearance of HEPs, including hemogenic (CD43+) HEPs and promoted subsequent differentiation into blood cells. Conversely, specific deletion of RUNX1c dramatically reduced the generation of hematopoietic cells from HEPs, indicating that RUNX1c is a master regulator of human hematopoietic development. Gene expression profiling of HEPs revealed a RUNX1c-induced pro-inflammatory molecular signature, supporting previous studies demonstrating pro-inflammatory signaling as a regulator of HSC emergence. Collectively, RUNX1c orchestrates hematopoietic specification of hPSCs, possibly in cooperation with pro-inflammatory signaling. This article is protected by copyright. All rights reserved. © 2017 AlphaMed Press.

  6. Small RNAs induce the activation of the pro-inflammatory TLR7 signaling pathway in aged rat kidney.

    PubMed

    Lee, Eun Kyeong; Chung, Ki Wung; Kim, Ye Ra; Ha, Sugyeong; Kim, Sung Dae; Kim, Dae Hyun; Jung, Kyung Jin; Lee, Bonggi; Im, Eunok; Yu, Byung Pal; Chung, Hae Young

    2017-10-01

    We have recently reported that TLR-related genes, including TLR7, are upregulated during aging. However, the role of TLR7 and its endogenous ligand in inflammation related to aging is not well defined. Here, we established that small RNAs trigger age-related renal inflammation via TLR7 signaling pathway. We first investigated the expression changes of nine different TLRs in kidney of 6-month-old young rats and 20-month-old aged rats. The results revealed that the expression of TLR7 was the highest among nine TLRs in kidney of old rats compared to the young aged rats. Next, to assess the role of cellular RNA as a TLR7 ligand, we treated a renal tubular epithelial cell line with total RNA isolated from the kidney of young and old rats. The results showed that RNA isolated from old rats showed higher expression of TLR7, IL1β, and TNFα compared to that from young rats. Furthermore, RNA isolated from old rats induced IKKα/β/JNK/NF-κB activation. To identify RNA that activates TLR7, we isolated small and large RNAs from old rat kidney and found that small RNAs increased TLR7 expression in cells. Finally, to investigate the local inflammatory response by small RNA, C57B/L6 mice were intraperitoneally injected with small RNAs isolated from young and old rats; thereby, RNA isolated from old rats induced higher inflammatory responses. Our study demonstrates that renal small RNAs from aged rats induce pro-inflammatory processes via the activation of the TLR7/IKKα/β/JNK/NF-κB signaling pathway, and highlights its causative role as a possible therapeutic target in age-related chronic renal inflammation. © 2017 The Authors. Aging Cell published by the Anatomical Society and John Wiley & Sons Ltd.

  7. Heterotrimeric G protein-dependent WNT-5A signaling to ERK1/2 mediates distinct aspects of microglia proinflammatory transformation

    PubMed Central

    2012-01-01

    Background WNT-5A signaling in the central nervous system is important for morphogenesis, neurogenesis and establishment of functional connectivity; the source of WNT-5A and its importance for cellular communication in the adult brain, however, are mainly unknown. We have previously investigated the inflammatory effects of WNT/β-catenin signaling in microglia in Alzheimer's disease. WNT-5A, however, generally recruits β-catenin-independent signaling. Thus, we aim here to characterize the role of WNT-5A and downstream signaling pathways for the inflammatory transformation of the brain's macrophages, the microglia. Methods Mouse brain sections were used for immunohistochemistry. Primary isolated microglia and astrocytes were employed to characterize the WNT-induced inflammatory transformation and underlying intracellular signaling pathways by immunoblotting, quantitative mRNA analysis, proliferation and invasion assays. Further, measurements of G protein activation by [γ-35 S]GTP binding, examination of calcium fluxes and cyclic AMP production were used to define intracellular signaling pathways. Results Astrocytes in the adult mouse brain express high levels of WNT-5A, which could serve as a novel astroglia-microglia communication pathway. The WNT-5A-induced proinflammatory microglia response is characterized by increased expression of inducible nitric oxide synthase, cyclooxygenase-2, cytokines, chemokines, enhanced invasive capacity and proliferation. Mapping of intracellular transduction pathways reveals that WNT-5A activates heterotrimeric Gi/o proteins to reduce cyclic AMP levels and to activate a Gi/o protein/phospholipase C/calcium-dependent protein kinase/extracellular signal-regulated kinase 1/2 (ERK1/2) axis. We show further that WNT-5A-induced ERK1/2 signaling is responsible for distinct aspects of the proinflammatory transformation, such as matrix metalloprotease 9/13 expression, invasion and proliferation. Conclusions Thus, WNT-5A-induced and G

  8. Pro-inflammatory stimulation of meniscus cells increases production of matrix metalloproteinases and additional catabolic factors involved in osteoarthritis pathogenesis

    PubMed Central

    Stone, Austin V.; Loeser, Richard F.; Vanderman, Kadie S.; Long, David L.; Clark, Stephanie C.; Ferguson, Cristin M.

    2014-01-01

    Objective Meniscus injury increases the risk of osteoarthritis; however, the biologic mechanism remains unknown. We hypothesized that pro-inflammatory stimulation of meniscus would increase production of matrix-degrading enzymes, cytokines and chemokines which cause joint tissue destruction and could contribute to osteoarthritis development. Design Meniscus and cartilage tissue from healthy tissue donors and total knee arthroplasties was cultured. Primary cell cultures were stimulated with pro-inflammatory factors [IL-1β, IL-6, or fibronectin fragments (FnF)] and cellular responses were analyzed by real-time PCR, protein arrays and immunoblots. To determine if NF-κB was required for MMP production, meniscus cultures were treated with inflammatory factors with and without the NF-κB inhibitor, hypoestoxide. Results Normal and osteoarthritic meniscus cells increased their MMP secretion in response to stimulation, but specific patterns emerged that were unique to each stimulus with the greatest number of MMPs expressed in response to FnF. Meniscus collagen and connective tissue growth factor gene expression was reduced. Expression of cytokines (IL-1α, IL-1β, IL-6), chemokines (IL-8, CXCL1, CXCL2, CSF1) and components of the NF-κB and tumor necrosis factor (TNF) family were significantly increased. Cytokine and chemokine protein production was also increased by stimulation. When primary cell cultures were treated with hypoestoxide in conjunction with pro-inflammatory stimulation, p65 activation was reduced as were MMP-1 and MMP-3 production. Conclusions Pro-inflammatory stimulation of meniscus cells increased matrix metalloproteinase production and catabolic gene expression. The meniscus could have an active biologic role in osteoarthritis development following joint injury through increased production of cytokines, chemokines, and matrix-degrading enzymes. PMID:24315792

  9. l-Theanine inhibits proinflammatory PKC/ERK/ICAM-1/IL-33 signaling, apoptosis, and autophagy formation in substance P-induced hyperactive bladder in rats.

    PubMed

    Tsai, Wen-Hsin; Wu, Chung-Hsin; Yu, Hong-Jeng; Chien, Chiang-Ting

    2017-02-01

    Upregulation of substance P (SP) and neurokinin-1 receptor (NK1R) activation induces pro-inflammatory bladder hyperactivity through the PKC/ERK/NF-κB/ICAM-1/IL-33 signaling pathways to increase the leukocyte infiltration and adhesion leading to reactive oxygen species (ROS) production, autophagy, and apoptosis. l-Theanine is a unique non-protein-forming amino acid present in tea (Camellia sinensis [L.] O. Kuntze) with its antioxidant, anti-inflammatory, and relaxation effects to improve cognition, mood, gastric ulcer injury, and cerebral ischemia/reperfusion injury, and posttraumatic stress disorder. We explored the protective effect of l-theanine on SP-induced bladder hyperactivity. In urethane-anesthetized female Wistar rats, we explored the transcystometrogram, pelvic nerve activity, proinflammatory PKC/ERK/NF-κB/ICAM-1/IL-33 signaling, apoptosis-related Caspase 3/poly-(ADP-ribose)-polymerase (PARP), and autophagy-mediated LC3 II expression by Western blot, electrophoretic-mobility shift assay and immunohistochemistry, bladder ROS amount by a ultrasensitive chemiluminescence method, and possible ROS sources from the different leukocytes by specific stains in SP-evoked hyperactive bladder. l-Theanine dose-dependently depressed H2 O2 and HOCl activity in vitro. In urethane-anesthetized female Wistar rats, intra-arterial SP through NK1R activation increased voiding frequency (shortened intercontraction intervals) associated with the increase in bladder nerve activity, proinflammatory PKC/ERK/NF-κB/ICAM-1/IL-33 signaling, Caspase 3/PARP-mediated apoptosis, LC3 II-mediated autophagy, ROS amount, neutrophils adhesion, CD68 (monocyte/macrophage) infiltration, and mast cells degranulation in the hyperactive bladder. Intragastrical l-theanine (15 mg/kg) twice daily for 2 weeks efficiently ameliorated all the enhanced parameters in the SP-treated hyperactive bladder. In conclusion, l-theanine through antioxidant and anti-inflammatory actions ameliorates SP

  10. Pro-inflammatory cytokine regulation of cyclic AMP-phosphodiesterase 4 signaling in microglia in vitro and following CNS injury

    PubMed Central

    Ghosh, Mousumi; Garcia-Castillo, Daniela; Aguirre, Vladimir; Golshani, Roozbeh; Atkins, Coleen M.; Bramlett, Helen M.; Dietrich, W. Dalton; Pearse, Damien D.

    2015-01-01

    Cyclic AMP suppresses immune cell activation and inflammation. The positive feedback loop of pro-inflammatory cytokine production and immune activation implies that cytokines may not only be regulated by cyclic AMP but conversely regulate cyclic AMP. This study examined the effects of TNF-α and IL-1β on cyclic AMP-phosphodiesterase (PDE) signaling in microglia in vitro and after spinal cord or traumatic brain injury (SCI, TBI). TNF-α or IL-1β stimulation produced a profound reduction (>90%) of cyclic AMP within EOC2 microglia from 30min that then recovered after IL-1β but remained suppressed with TNF-α through 24h. Cyclic AMP was also reduced in TNF-α-stimulated primary microglia, albeit to a lesser extent. Accompanying TNF-α-induced cyclic AMP reductions, but not IL-1β, was increased cyclic AMP-PDE activity. The role of PDE4 activity in cyclic AMP reductions was confirmed by using Rolipram. Examination of pde4 mRNA revealed an immediate, persistent increase in pde4b with TNF-α; IL-1β increased all pde4 mRNAs. Immunoblotting for PDE4 showed that both cytokines increased PDE4A1, but only TNF-α increased PDE4B2. Immunocytochemistry revealed PDE4B nuclear translocation with TNF-α but not IL-1β. Acutely after SCI/TBI, where cyclic AMP levels are reduced, PDE4B was localized to activated OX-42+ microglia; PDE4B was absent in OX-42+ cells in uninjured spinal cord/cortex or inactive microglia. Immunoblotting showed PDE4B2 up-regulation from 24h to 1wk post-SCI, the peak of microglia activation. These studies show that TNF-α and IL-1β differentially affect cyclic AMP-PDE signaling in microglia. Targeting PDE4B2 may be a putative therapeutic direction for reducing microglia activation in CNS injury and neurodegenerative diseases. PMID:22865690

  11. Increased levels of HMGB1 and pro-inflammatory cytokines in children with febrile seizures.

    PubMed

    Choi, Jieun; Min, Hyun Jin; Shin, Jeon-Soo

    2011-10-11

    Febrile seizures are the most common form of childhood seizures. Fever is induced by pro-inflammatory cytokines during infection, and pro-inflammatory cytokines may trigger the development of febrile seizures. In order to determine whether active inflammation, including high mobility group box-1 (HMGB1) and pro-inflammatory cytokines, occurs in children with febrile seizures or epilepsy, we analyzed cytokine profiles of patients with febrile seizures or epilepsy. Forty-one febrile seizure patients who visited the emergency department of Seoul National University Boramae Hospital from June 2008 to May 2009 were included in this study. Blood was obtained from the febrile seizure child patients within 30 minutes of the time of the seizure; subsequently, serum cytokine assays were performed. Control samples were collected from children with febrile illness without convulsion (N = 41) and similarly analyzed. Serum samples from afebrile status epilepticus attacks in intractable epilepsy children (N = 12), afebrile seizure attacks in generalized epilepsy with febrile seizure plus (GEFSP) children (N = 6), and afebrile non-epileptic controls (N = 7) were also analyzed. Serum HMGB1 and IL-1β levels were significantly higher in febrile seizure patients than in fever only controls (p < 0.05). Serum IL-6 levels were significantly higher in typical febrile seizures than in fever only controls (p < 0.05). Serum IL-1β levels were significantly higher in status epilepticus attacks in intractable epilepsy patients than in fever only controls (p < 0.05). Serum levels of IL-1β were significantly correlated with levels of HMGB1, IL-6, and TNF-α (p < 0.05). HMGB1 and pro-inflammatory cytokines were significantly higher in febrile seizure children. Although it is not possible to infer causality from descriptive human studies, our data suggest that HMGB1 and the cytokine network may contribute to the generation of febrile seizures in children. There may be a potential role for anti

  12. Increased levels of HMGB1 and pro-inflammatory cytokines in children with febrile seizures

    PubMed Central

    2011-01-01

    Objective Febrile seizures are the most common form of childhood seizures. Fever is induced by pro-inflammatory cytokines during infection, and pro-inflammatory cytokines may trigger the development of febrile seizures. In order to determine whether active inflammation, including high mobility group box-1 (HMGB1) and pro-inflammatory cytokines, occurs in children with febrile seizures or epilepsy, we analyzed cytokine profiles of patients with febrile seizures or epilepsy. Methods Forty-one febrile seizure patients who visited the emergency department of Seoul National University Boramae Hospital from June 2008 to May 2009 were included in this study. Blood was obtained from the febrile seizure child patients within 30 minutes of the time of the seizure; subsequently, serum cytokine assays were performed. Control samples were collected from children with febrile illness without convulsion (N = 41) and similarly analyzed. Serum samples from afebrile status epilepticus attacks in intractable epilepsy children (N = 12), afebrile seizure attacks in generalized epilepsy with febrile seizure plus (GEFSP) children (N = 6), and afebrile non-epileptic controls (N = 7) were also analyzed. Results Serum HMGB1 and IL-1β levels were significantly higher in febrile seizure patients than in fever only controls (p < 0.05). Serum IL-6 levels were significantly higher in typical febrile seizures than in fever only controls (p < 0.05). Serum IL-1β levels were significantly higher in status epilepticus attacks in intractable epilepsy patients than in fever only controls (p < 0.05). Serum levels of IL-1β were significantly correlated with levels of HMGB1, IL-6, and TNF-α (p < 0.05). Conclusions HMGB1 and pro-inflammatory cytokines were significantly higher in febrile seizure children. Although it is not possible to infer causality from descriptive human studies, our data suggest that HMGB1 and the cytokine network may contribute to the generation of febrile seizures in children

  13. Astrocyte TLR4 activation induces a proinflammatory environment through the interplay between MyD88-dependent NFκB signaling, MAPK, and Jak1/Stat1 pathways.

    PubMed

    Gorina, Roser; Font-Nieves, Miriam; Márquez-Kisinousky, Leonardo; Santalucia, Tomàs; Planas, Anna M

    2011-02-01

    There is increasing evidence that astrocytes play important roles in immune regulation in the brain. Astrocytes express toll-like receptors (TLR) and build up responses to innate immune triggers by releasing proinflammatory molecules. We investigate signaling pathways and released molecules after astrocyte TLR4 activation. Purified rodent brain astrocyte cultures were treated with the TLR4 activator bacterial lipopolysaccharide (LPS). Tools used to interfere with this system include small interference RNA, inhibitory drugs, and MyD88 or Stat1 deficient mice. LPS induced early activation of the transcription factor NFκB, through the MyD88 adaptor, and expression of TNF-α, VCAM-1, IL-15, and IL-27. LPS also induced delayed Jak1/Stat1 activation, which was MyD88-independent but was not mediated by IFN-β. Jak1/Stat1 activation induced the expression of negative cytokine regulator SOCS-1 and CXCL10 chemokine (IP-10). Mitogen-activated protein kinases (MAPK) were also involved in TLR4 signaling in a MyD88-independent fashion. p38 exerted a strong influence on LPS-induced gene expression by regulating the phosphorylation of Stat1 and the transcriptional activity of NFκB, while JNK regulated the Jak1/Stat1 pathway, and ERK1/2 controlled the expression of Egr-1 and influenced MyD88-dependent MMP-9 expression. Interplay between these signals was evidenced by the increased induction of MMP-9 in Stat1-deficient cells challenged with LPS, suggesting that Stat1 negatively regulates the expression of MMP-9 induced by LPS. Therefore, astrocytes are responsive to TLR4 activation by inducing a complex set of cell-dependent molecular reactions mediated by NFκB, MAPK and Jak1/Stat1 signaling pathways. Here we identified cross-talking signals generating a proinflammatory environment that will modulate the response of surrounding cells. © 2010 Wiley-Liss, Inc.

  14. Notch Activation Induces Endothelial Cell Senescence and Pro-inflammatory Response: Implication of Notch Signaling in Atherosclerosis

    PubMed Central

    Liu, Zhao-Jun; Tan, Yurong; Beecham, Gary W.; Seo, David M.; Tian, Runxia; Li, Yan; Vazquez-Padron, Roberto I.; Pericak-Vance, Margaret; Vance, Jeffery M.; Goldschmidt-Clermont, Pascal J.; Livingstone, Alan S.; Velazquez, Omaida C.

    2012-01-01

    Objective Notch signaling plays pivotal roles in the pathogenesis of vascular disease. However, little is known about its role in atherosclerosis. We sought to investigate the potential involvement of the Notch signaling in atherosclerosis. Methods Expression of Notch pathway components in mouse and human aorta with or without atherosclerosis plaque was examined by immuno-histochemistry. Expression of Notch target genes in young versus aged human endothelial cells (EC) was examined by PCRArray and immunoblot. In vitro loss- and gain-of-function approaches were utilized to evaluate the role of Notch signaling in inducing EC senescence and secretion of pro-inflammatory cytokines by ProteinArray. Notch gene profile was studied in 1054 blood samples of patients with coronary artery disease (CAD). Genotyping was performed using the Genome-Wide Single Nucleotide Polymorphism (SNP) Array. Results Notch pathway components were upregulated in luminal EC at atherosclerotic lesions from mouse and human aortas. In addition, the Notch pathway was activated in aged but not young human EC. Enforced Notch activation resulted in EC senescence and significantly upregulated expression of several molecules implicated in the inflammatory response (IL-6/IL-8/IL-1α/RANTES/ICAM-1). The upregulated IL-6 was partially responsible for mediating leukocyte transendothelial migration. Genetic association analysis detected, of 82 SNPs across 6 Notch pathway genes analyzed, 4 SNPs with nominal association with CAD burden. Conclusion Notch pathway is activated in luminal EC at atherosclerotic plaques and results in pro-inflammatory response and senescence of EC. Notch signaling may be linked to human CAD risk. These findings implicate a potential involvement of Notch signaling in atherosclerosis. PMID:23078884

  15. Increased production of proinflammatory cytokines following infection with porcine reproductive and respiratory syndrome virus and Mycoplasma hyopneumoniae.

    PubMed

    Thanawongnuwech, Roongroje; Thacker, Brad; Halbur, Patrick; Thacker, Eileen L

    2004-09-01

    Induction of the proinflammatory cytokines interleukin-1 (IL-1) (alpha and beta), IL-6, IL-8, IL-10, IL-12, and tumor necrosis factor alpha (TNF-alpha) in pulmonary alveolar macrophages (PAMs) was assessed following experimental infection with porcine reproductive and respiratory syndrome virus (PRRSV) and/or Mycoplasma hyopneumoniae by using in vivo and in vitro models. The in vivo model consisted of pigs infected with PRRSV and/or M. hyopneumoniae and necropsied at 10, 28, or 42 days postinfection. Pigs infected with both pathogens had a greater percentage of macroscopic lung lesions, increased clinical disease, and slower viral clearance than pigs infected with either pathogen alone. The pigs infected with both PRRSV and M. hyopneumoniae had significantly increased levels of mRNA for many proinflammatory cytokines in PAMs collected by bronchoalveolar lavage (BAL) at all necropsy dates compared to those in uninfected control pigs. Increased levels of IL-1beta, IL-8, IL-10, and TNF-alpha proteins in BAL fluid, as measured by enzyme-linked immunosorbent assay, confirmed the increased cytokine induction induced by the pathogens. An in vitro model consisted of M. hyopneumoniae-inoculated tracheal ring explants cultured with PRRSV-infected PAMs. PAMs were harvested at 6 or 15 h postinfection with either or both pathogens. The in vitro study detected increased IL-10 and IL-12 mRNA levels in PAMs infected with PRRSV at all time periods. In addition, IL-10 protein levels were significantly elevated in the culture supernatants in the presence of M. hyopneumoniae-inoculated tracheal ring explants. The increased production of proinflammatory cytokines in vivo and in vitro associated with concurrent M. hyopneumoniae and PRRSV infection may play a role in the increased rates of pneumonia associated with PRRSV infection. The increased levels of IL-10 may be a possible mechanism that PRRSV and M. hyopneumoniae use to exacerbate the severity and duration of pneumonia induced by

  16. The Effect of Therapeutic Blockades of Dust Particles-Induced Ca2+ Signaling and Proinflammatory Cytokine IL-8 in Human Bronchial Epithelial Cells

    PubMed Central

    Yoon, Ju Hee; Jeong, Sung Hwan; Hong, Jeong Hee

    2015-01-01

    Bronchial epithelial cells are the first barrier of defense against respiratory pathogens. Dust particles as extracellular stimuli are associated with inflammatory reactions after inhalation. It has been reported that dust particles induce intracellular Ca2+ signal, which subsequently increases cytokines production such as interleukin- (IL-) 8. However, the study of therapeutic blockades of Ca2+ signaling induced by dust particles in human bronchial epithelial cells is poorly understood. We investigated how to modulate dust particles-induced Ca2+ signaling and proinflammatory cytokine IL-8 expression. Bronchial epithelial BEAS-2B cells were exposed to PM10 dust particles and subsequent mediated intracellular Ca2+ signaling and reactive oxygen species signal. Our results show that exposure to several inhibitors of Ca2+ pathway attenuated the PM10-induced Ca2+ response and subsequent IL-8 mRNA expression. PM10-mediated Ca2+ signal and IL-8 expression were attenuated by several pharmacological blockades such as antioxidants, IP3-PLC blockers, and TRPM2 inhibitors. Our results show that blockades of PLC or TRPM2 reduced both of PM10-mediated Ca2+ signal and IL-8 expression, suggesting that treatment with these blockades should be considered for potential therapeutic trials in pulmonary epithelium for inflammation caused by environmental events such as seasonal dust storm. PMID:26640326

  17. Inhibiting IκBβ–NFκB signaling attenuates the expression of select pro-inflammatory genes

    PubMed Central

    McKenna, Sarah; Wright, Clyde J.

    2015-01-01

    ABSTRACT Multiple mediators of septic shock are regulated by the transcription factor nuclear factor κB (NFκB). However, complete NFκB inhibition can exacerbate disease, necessitating evaluation of targeted strategies to attenuate the pro-inflammatory response. Here, we demonstrate that in murine macrophages, low-dose NFκB inhibitors specifically attenuates lipopolysaccharide (LPS)-induced IκBβ degradation and the expression of a select subset of target genes (encoding IL1β, IL6, IL12β). Gain- and loss-of-function experiments demonstrate the necessary and sufficient role of inhibitor of NFκB family member IκBβ (also known as NFKBIB) in the expression of these genes. Furthermore, both fibroblasts and macrophages isolated from IκBβ overexpressing mice demonstrate attenuated LPS-induced IκBβ–NFκB signaling and IL1β, IL6 and IL12β expression. Further confirming the role of IκBβ and its NFκB subunit binding partner cRel in LPS-induced gene expression, pre-treatment of wild-type mouse embryonic fibroblasts with a cell-permeable peptide containing the cRel nuclear localization sequence attenuated IL6 expression. We prove that LPS-induced IκBβ–NFκB signaling can be selectively modulated to attenuate the expression of select pro-inflammatory target genes, thus providing therapeutic insights for patients exposed to systemic inflammatory stress. PMID:25908863

  18. Increased cellular free cholesterol in macrophage-specific Abca1 knock-out mice enhances pro-inflammatory response of macrophages.

    PubMed

    Zhu, Xuewei; Lee, Ji-Young; Timmins, Jenelle M; Brown, J Mark; Boudyguina, Elena; Mulya, Anny; Gebre, Abraham K; Willingham, Mark C; Hiltbold, Elizabeth M; Mishra, Nilamadhab; Maeda, Nobuyo; Parks, John S

    2008-08-22

    Macrophage-specific Abca1 knock-out (Abca1(-)(M)(/-)(M)) mice were generated to determine the role of macrophage ABCA1 expression in plasma lipoprotein concentrations and the innate immune response of macrophages. Plasma lipid and lipoprotein concentrations in chow-fed Abca1(-)(M)(/-)(M) and wild-type (WT) mice were indistinguishable. Compared with WT macrophages, Abca1(-)(M)(/-)(M) macrophages had a >95% reduction in ABCA1 protein, failed to efflux lipid to apoA-I, and had a significant increase in free cholesterol (FC) and membrane lipid rafts without induction of endoplasmic reticulum stress. Lipopolysaccharide (LPS)-treated Abca1(-)(M)(/-)(M) macrophages exhibited enhanced expression of pro-inflammatory cytokines and increased activation of the NF-kappaB and MAPK pathways, which could be diminished by silencing MyD88 or by chemical inhibition of NF-kappaB or MAPK. In vivo LPS injection also resulted in a higher pro-inflammatory response in Abca1(-)(M)(/-)(M) mice compared with WT mice. Furthermore, cholesterol depletion of macrophages with methyl-beta-cyclodextrin normalized FC content between the two genotypes and their response to LPS; cholesterol repletion of macrophages resulted in increased cellular FC accumulation and enhanced cellular response to LPS. Our results suggest that macrophage ABCA1 expression may protect against atherosclerosis by facilitating the net removal of excess lipid from macrophages and dampening pro-inflammatory MyD88-dependent signaling pathways by reduction of cell membrane FC and lipid raft content.

  19. Oxidative stress and pro-inflammatory cytokines may act as one of the signals for regulating microRNAs expression in Alzheimer's disease.

    PubMed

    Prasad, Kedar N

    2017-03-01

    Oxidative stress and chronic inflammation are one of the earliest defects that initiate and promote Alzheimer's disease (AD). Studies showed that expressions of microRNAs were upregulated or downregulated in AD. Therefore, these biochemical defects may influence the levels of microRNAs. The up-regulated microRNAs cause neurodegeneration by: (a) decreasing the levels of a nuclear transcriptional factor-2 (Nrf2), (b) reducing the levels of α-secretase ADM10; and (c) reducing the levels of phosphatases. The down-regulated microRNAs cause neurodegeneration by: (a) increasing the levels of β-secretase, (b) increasing the levels of tau kinase; (c) elevating the levels of tau proteins; (d) increasing the levels of APP; and (e) increasing the levels of nuclear factor-kappaB (NF-kB). Antioxidants protect neurons by reducing oxidative stress and chronic inflammation. Therefore, they may also influence the levels of microRNAs. This review briefly describes the studies on changes in the expressions of microRNAs in the pathogenesis of AD. It proposes a hypothesis that free radicals and pro-inflammatory cytokines act as one of the signals that upregulate or downregulate the levels of microRNAs by influencing their transcription, processing or stability leading to neurodegeneration in AD. Antioxidants that reduce oxidative stress and pro-inflammatory cytokines also regulate the levels of microRNAs.

  20. Long-Term Dietary Sodium Restriction Increases Adiponectin Expression and Ameliorates the Proinflammatory Adipokine Profile in Obesity

    PubMed Central

    Baudrand, R; Lian, CG; Lian, BQ; Ricchiuti, V; Yao, TM; Li, J; Williams, GH; Adler, GK

    2015-01-01

    Background/Aim Obesity is associated with changes in adiponectin and pro-inflammatory adipokines. Sodium intake can affect adipokine secretion suggesting a role in cardiovascular dysfunction. We tested if long-term dietary sodium restriction modifies the expression of adiponectin and ameliorates the pro-inflammatory profile of obese, diabetic Methods/Results Db/db mice were randomized to high sodium (HS 1.6% Na+, n=6) or low sodium (LS 0.03% Na+, n=8) diet for 16 weeks and compared with lean, db/+ mice on HS diet (n=8). Insulin levels were 50% lower in the db/db mice on LS diet when compared with HS db/db (p <0.05). LS diet increased cardiac adiponectin mRNA levels in db/db mice by 5-fold when compared with db/db mice on HS diet and by 2-fold when compared with HS lean mice (both p < 0.01). LS diet increased adiponectin in adipose tissue compared with db/db mice on HS diet, achieving levels similar to those of lean mice. MCP-1, IL-6 and TNF-α expression were reduced more than 50% in adipose tissue of db/db mice on LS diet when compared with HS db/db mice (all p < 0.05), to levels observed in the HS lean mice. Further, LS db/db mice had significantly reduced circulating MCP-1 and IL-6 levels when compared with HS db/db mice (both p < 0.01). Conclusion In obese-diabetic mice, long-term LS diet increases adiponectin in heart and adipose tissue and reduces pro-inflammatory factors in adipose tissue and plasma. These additive mechanisms may contribute to the potential cardioprotective benefits of LS diet in obesity-related metabolic disorders. PMID:24418377

  1. Long-term dietary sodium restriction increases adiponectin expression and ameliorates the proinflammatory adipokine profile in obesity.

    PubMed

    Baudrand, R; Lian, C G; Lian, B Q; Ricchiuti, V; Yao, T M; Li, J; Williams, G H; Adler, G K

    2014-01-01

    Obesity is associated with changes in adiponectin and pro-inflammatory adipokines. Sodium intake can affect adipokine secretion suggesting a role in cardiovascular dysfunction. We tested if long-term dietary sodium restriction modifies the expression of adiponectin and ameliorates the pro-inflammatory profile of obese, diabetic mice. Db/db mice were randomized to high sodium (HS 1.6% Na+, n = 6) or low sodium (LS 0.03% Na+, n = 8) diet for 16 weeks and compared with lean, db/+ mice on HS diet (n = 8). Insulin levels were 50% lower in the db/db mice on LS diet when compared with HS db/db (p < 0.05). LS diet increased cardiac adiponectin mRNA levels in db/db mice by 5-fold when compared with db/db mice on HS diet and by 2-fold when compared with HS lean mice (both p < 0.01). LS diet increased adiponectin in adipose tissue compared with db/db mice on HS diet, achieving levels similar to those of lean mice. MCP-1, IL-6 and TNF-α expression were reduced more than 50% in adipose tissue of db/db mice on LS diet when compared with HS db/db mice (all p < 0.05), to levels observed in the HS lean mice. Further, LS db/db mice had significantly reduced circulating MCP-1 and IL-6 levels when compared with HS db/db mice (both p < 0.01). In obese-diabetic mice, long-term LS diet increases adiponectin in heart and adipose tissue and reduces pro-inflammatory factors in adipose tissue and plasma. These additive mechanisms may contribute to the potential cardioprotective benefits of LS diet in obesity-related metabolic disorders. Copyright © 2013 Elsevier B.V. All rights reserved.

  2. Targeting apoptotic signalling pathway and pro-inflammatory cytokine expression as therapeutic intervention in TPE induced lung damage.

    PubMed

    Narayanan, Kishore; Krishnamoorthy, Bhavani; Ezhilarasan, Ravesanker; Miyamoto, Shigeki; Balakrishnan, Arun

    2003-01-01

    Tropical pulmonary eosinophilia (TPE) is an occult manifestation of filariasis, brought about by helminth parasites Wuchereria bancrofti and Brugia malayi. Treatment of patients suffering from TPE involves the administration of diethyl carbamazine and Ivermectin. Although the drugs are able to block acute inflammation, they are not able to alleviate chronic basal inflammation. We have attempted to examine the disease by targeting two important components; namely filarial parasitic sheath proteins (FPP) induced apoptosis and pro-inflammatory cytokine response in human laryngeal carcinoma cells of epithelial origin (HEp-2) cells an epithelial cell line. Earlier studies by us have shown that FPP exposure induced apoptosis in these cells. In this study with hydrocortisone, calpain inhibitor (ALLN) and phorbol myristate acetate (PMA) treatments we demonstrate that apoptosis is inhibited as shown by [3H] thymidine incorporation studies, propidium iodide staining and Annexin V staining. Hydrocortisone at a dose, which inhibits cell death also down regulated, the expression of pro-inflammatory cytokines IL-6 and IL-8. These findings give us insights into the multifaceted approach one may adopt to target critical signalling molecules using appropriate inhibitors, which could eventually be used to reduce lung damage in TPE.

  3. Extracellular poly(ADP-ribose) is a pro-inflammatory signal for macrophages

    PubMed Central

    Krukenberg, Kristin A.; Kim, Sujeong; Tan, Edwin S.; Maliga, Zoltan; Mitchison, Timothy J.

    2015-01-01

    Summary Poly(ADP-ribose) polymerase 1 (PARP1) synthesizes poly(ADP-ribose) (PAR), an essential post-translational modification whose function is important in many cellular processes including DNA damage signalling, cell death, and inflammation. All known PAR biology is intracellular, but we suspected it might also play a role in cell-to-cell communication during inflammation. We found that PAR activated cytokine release in human and mouse macrophages, a hallmark of innate immune activation, and determined structure-activity relationships. PAR was rapidly internalized by murine macrophages, while the monomer, ADP-ribose, was not. Inhibitors of TLR2 and TLR4 signaling blocked macrophage responses to PAR, and PAR induced TLR2 and TLR4 signaling in reporter cell lines suggesting it was recognized by these TLRs, much like bacterial pathogens. We propose that PAR acts as an extracellular “Damage Associated Molecular Pattern” (DAMP) that drives inflammatory signaling. PMID:25865309

  4. Melatonin Suppresses Toll Like Receptor 4-Dependent Caspase-3 Signaling Activation Coupled with Reduced Production of Proinflammatory Mediators in Hypoxic Microglia

    PubMed Central

    Yao, Linli; Lu, Pengfei; Ling, Eng-Ang

    2016-01-01

    Microglia activation and associated inflammatory response play pivotal roles in the pathogenesis of different neurodegenerative diseases including neonatal hypoxic brain injury. Here we show that caspase3 expression was upregulated in activated microglia after hypoxic exposure, and remarkably, the cell viability remained unaffected alluding to the possibility of a non-apoptotic role of caspase3 in activated microglia. Chemical inhibition of caspase3 suppressed microglia activation as evident by an obvious reduction in expression of proinflammatory mediators and NF-κB signaling activation. Hypoxia induced caspase3 activation was TLR4 dependent as supported by the fact that caspase3 activation was hindered in cells with TLR4 knockdown. Interestingly, melatonin treatment significantly suppressed caspase3 activation. More importantly, melatonin also inhibited the increase in TLR4 protein and mRNA expression in hypoxic microglia. Inhibition of TLR4 expression by melatonin was also found in microglia of postnatal rats subjected to hypoxic exposure. Taken together, it is concluded that melatonin could inhibit TLR4 expression in hypoxic microglia followed by suppression of caspase3 activation leading to decrease in production of proinflammatory mediators. PMID:27812200

  5. Ebola virus-like particles stimulate type I interferons and proinflammatory cytokine expression through the toll-like receptor and interferon signaling pathways.

    PubMed

    Ayithan, Natarajan; Bradfute, Steven B; Anthony, Scott M; Stuthman, Kelly S; Dye, John M; Bavari, Sina; Bray, Mike; Ozato, Keiko

    2014-02-01

    Ebola viruses (EBOV) can cause severe hemorrhagic disease with high case fatality rates. Currently, no vaccines or therapeutics are approved for use in humans. Ebola virus-like particles (eVLP) comprising of virus protein (VP40), glycoprotein, and nucleoprotein protect rodents and nonhuman primates from lethal EBOV infection, representing as a candidate vaccine for EBOV infection. Previous reports have shown that eVLP stimulate the expression of proinflammatory cytokines in dendritic cells (DCs) and macrophages (MΦs) in vitro. However, the molecular mechanisms and signaling pathways through which eVLP induce innate immune responses remain obscure. In this study, we show that eVLP stimulate not only the expression of proinflammatory cytokines but also the expression of type I interferons (IFNs) and IFN-stimulated genes (ISGs) in murine bone marrow-derived DCs (BMDCs) and MΦs. Our data indicate that eVLP trigger host responses through toll-like receptor (TLR) pathway utilizing 2 distinct adaptors, MyD88 and TRIF. More interestingly, eVLP activated the IFN signaling pathway by inducing a set of potent antiviral ISGs. Last, eVLP and synthetic adjuvants, Poly I:C and CpG DNA, cooperatively increased the expression of cytokines and ISGs. Further supporting this synergy, eVLP when administered together with Poly I:C conferred mice enhanced protection against EBOV infection. These results indicate that eVLP stimulate early innate immune responses through TLR and type I IFN signaling pathways to protect the host from EBOV infection.

  6. Fibroblast growth factor signalling in multiple sclerosis: inhibition of myelination and induction of pro-inflammatory environment by FGF9.

    PubMed

    Lindner, Maren; Thümmler, Katja; Arthur, Ariel; Brunner, Sarah; Elliott, Christina; McElroy, Daniel; Mohan, Hema; Williams, Anna; Edgar, Julia M; Schuh, Cornelia; Stadelmann, Christine; Barnett, Susan C; Lassmann, Hans; Mücklisch, Steve; Mudaliar, Manikhandan; Schaeren-Wiemers, Nicole; Meinl, Edgar; Linington, Christopher

    2015-07-01

    Remyelination failure plays an important role in the pathophysiology of multiple sclerosis, but the underlying cellular and molecular mechanisms remain poorly understood. We now report actively demyelinating lesions in patients with multiple sclerosis are associated with increased glial expression of fibroblast growth factor 9 (FGF9), which we demonstrate inhibits myelination and remyelination in vitro. This inhibitory activity is associated with the appearance of multi-branched 'pre-myelinating' MBP+ / PLP+ oligodendrocytes that interact with axons but fail to assemble myelin sheaths; an oligodendrocyte phenotype described previously in chronically demyelinated multiple sclerosis lesions. This inhibitory activity is not due to a direct effect of FGF9 on cells of the oligodendrocyte lineage but is mediated by factors secreted by astrocytes. Transcriptional profiling and functional validation studies demonstrate that these include effects dependent on increased expression of tissue inhibitor of metalloproteinase-sensitive proteases, enzymes more commonly associated with extracellular matrix remodelling. Further, we found that FGF9 induces expression of Ccl2 and Ccl7, two pro-inflammatory chemokines that contribute to recruitment of microglia and macrophages into multiple sclerosis lesions. These data indicate glial expression of FGF9 can initiate a complex astrocyte-dependent response that contributes to two distinct pathogenic pathways involved in the development of multiple sclerosis lesions. Namely, induction of a pro-inflammatory environment and failure of remyelination; a combination of effects predicted to exacerbate axonal injury and loss in patients.

  7. Diesel exhaust particles induce oxidative stress, proinflammatory signaling, and P-glycoprotein up-regulation at the blood-brain barrier.

    PubMed

    Hartz, Anika M S; Bauer, Björn; Block, Michelle L; Hong, Jau-Shyong; Miller, David S

    2008-08-01

    Here, we report that diesel exhaust particles (DEPs), a major constituent of urban air pollution, affect blood-brain barrier function at the tissue, cellular, and molecular levels. Isolated rat brain capillaries exposed to DEPs showed increased expression and transport activity of the key drug efflux transporter, P-glycoprotein (6 h EC(50) was approximately 5 microg/ml). Up-regulation of P-glycoprotein was abolished by blocking transcription or protein synthesis. Inhibition of NADPH oxidase or pretreatment of capillaries with radical scavengers ameliorated DEP-induced P-glycoprotein up-regulation, indicating a role for reactive oxygen species in signaling. DEP exposure also increased brain capillary tumor necrosis factor-alpha (TNF-alpha) levels. DEP-induced P-glycoprotein up-regulation was abolished when TNF-receptor 1 (TNF-R1) was blocked and was not evident in experiments with capillaries from TNF-R1 knockout mice. Inhibition of JNK, but not NF-kappaB, blocked DEP-induced P-glycoprotein up-regulation, indicating a role for AP-1 in the signaling pathway. Consistent with this, DEPs increased phosphorylation of c-jun. Together, our results show for the first time that a component of air pollution, DEPs, alters blood-brain barrier function through oxidative stress and proinflammatory cytokine production. These experiments disclose a novel blood-brain barrier signaling pathway, with clear implications for environmental toxicology, CNS pathology, and the pharmacotherapy of CNS disorders.

  8. Proinflammatory Signals as Fuel for the Fire of Hematopoietic Stem Cell Emergence.

    PubMed

    Espin-Palazon, Raquel; Weijts, Bart; Mulero, Victor; Traver, David

    2017-09-04

    Hematopoietic stem cells (HSCs) have the extraordinary ability to both self-renew and generate all mature blood cell lineages. The ability to produce or expand patient-derived HSCs in vitro would greatly improve the outcome for patients with blood disorders that are currently treated with allogeneic HSC transplantation. Many laboratories have been working to identify the signals required for HSC emergence in their native environments to apply this knowledge in vitro. Recently, several signals traditionally known to underlie classical inflammation have emerged as essential regulators of HSC development. In this review we synthesize the findings that have established inflammatory cues as key regulators of HSC development. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Morphine mediates a proinflammatory phenotype via μ-opioid receptor-PKCɛ-Akt-ERK1/2 signaling pathway in activated microglial cells.

    PubMed

    Merighi, Stefania; Gessi, Stefania; Varani, Katia; Fazzi, Debora; Stefanelli, Angela; Borea, Pier Andrea

    2013-08-15

    Anti-nociceptive tolerance to opioids severely limits their clinical efficacy for the treatment of chronic pain syndromes. Glia has a central role in the development of morphine tolerance. Here, we characterized the receptor-proximal signaling events that link μ-opioid receptors to activation of Akt and ERKs in lipopolysaccharide (LPS)-stimulated murine microglial cells with the aim to define the molecular mechanism contributing to the ability of morphine to increase inflammatory mediators such as nitric oxide (NO), tumor necrosis factor (TNF)-α, interleukin (IL)-1β and IL-6 in activated microglial cells. In particular, the role of PKCɛ isoform in μ-opioid-induced inflammatory response in microglia was investigated. The results indicate that morphine increases the LPS-induced expression and activation of PKCɛ and stimulates Akt pathway upstream of ERK1/2 and iNOS. Furthermore, we found that morphine enhanced the release of IL-1β, TNF-α, IL-6, and of NO via μ-opioid receptor-PKCɛ signaling pathway in activated microglial cells, mediating a proinflammatory phenotype in mouse microglial cells. Together, these data suggest that the modulation of μ-opioid receptor signaling on microglia through PKCɛ selective inhibition may provide a means to attenuate glial activation and, as a consequence, to treat opioid development of tolerance and dependence.

  10. Proinflammatory signal transduction pathway induced by Shigella flexneri porins in caco-2 cells

    PubMed Central

    Elena, Grimaldi; Giovanna, Donnarumma; Brunella, Perfetto; De Anna, Filippis; Alessandro, Melito; Antonietta, Tufano Maria

    2009-01-01

    The recognition of bacterial components on the intestinal epithelial cells occurs through the toll-like receptors and is followed by the induction of an effective innate immune response. We analyzed receptor expression and signaling pathways involved in activation of human colon adenocarcinoma cells after stimulation with porins and LPS of Shigella flexneri. We also analyzed the expression and production of some cytokines, of intercellular adhesion molecule-1, of antimicrobial peptides human β-defensins, and of the inducible form of nitric oxide synthase. Our data demonstrate that TLR2 is involved in porin recognition, whereas TLR4 with MD2, is required for LPS recognition. PMID:24031417

  11. TRPV1 is crucial for proinflammatory STAT3 signaling and thermoregulation-associated pathways in the brain during inflammation

    PubMed Central

    Yoshida, Ayaka; Furube, Eriko; Mannari, Tetsuya; Takayama, Yasunori; Kittaka, Hiroki; Tominaga, Makoto; Miyata, Seiji

    2016-01-01

    Transient receptor potential vanilloid receptor 1 (TRPV1) is a non-selective cation channel that is stimulated by heat (>43 °C), mechanical/osmotic stimuli, and low pH. The importance of TRPV1 in inflammatory responses has been demonstrated, whereas its participation in brains remains unclear. In the present study, the intracerebroventricular (icv) administration of the TRPV1 agonist resiniferatoxin (RTX) induced the activation of signal transducer and activator of transcription 3 (STAT3) in circumventricular organs (CVOs) and thermoregulation-associated brain regions with a similar patttern to the peripheral and icv administration of lipopolysaccharide (LPS). With the peripheral and icv LPS stimuli, STAT3 activation was significantly lower in Trpv1−/− mice than in Trpv1+/+ mice. The icv administration of RTX induced transient hypothermia, whereas that of the TRPV1 antagonist capsazepine enhanced the magnitude and period of LPS-induced hyperthermia. These results indicate that TRPV1 is important for activating proinflammatory STAT3 signaling and thermoregulation-associated brain pathways in the brain. PMID:27188969

  12. A TLR4/MD2 fusion protein inhibits LPS-induced pro-inflammatory signaling in hepatic stellate cells

    SciTech Connect

    Schnabl, Bernd Brandl, Katharina; Fink, Marina; Gross, Philipp; Taura, Kojiro; Gaebele, Erwin; Hellerbrand, Claus; Falk, Werner

    2008-10-17

    Activated hepatic stellate cells (HSCs) play a key role in hepatic fibrogenesis. In injured liver they are the main extracellular matrix protein producing cell type and further perpetuate hepatic injury by secretion of pro-inflammatory mediators. Since LPS-mediated signaling through toll-like receptor 4 (TLR4) has been identified as key fibrogenic signal in HSCs we aimed to test TLR4 as potential target of therapy via ligand-binding soluble receptors. Incubation of human HSCs with a fusion protein between the extracellular domain of TLR4 and MD2 which binds LPS inhibited LPS-induced NF{kappa}B and JNK activation. TLR4/MD2 abolished LPS-induced secretion of IL-6, IL-8, MCP1, and RANTES in HSCs. In addition, TLR4/MD2 fused to human IgG-Fc neutralized LPS activity. Since TLR4 mutant mice are resistant to liver fibrosis, the TLR4/MD2 soluble receptor might represent a new therapeutic molecule for liver fibrogenesis in vivo.

  13. Proinflammatory cytokine signaling required for the generation of natural killer cell memory

    PubMed Central

    Sun, Joseph C.; Madera, Sharline; Bezman, Natalie A.; Beilke, Joshua N.; Kaplan, Mark H.

    2012-01-01

    Although natural killer (NK) cells are classified as innate immune cells, recent studies demonstrate that NK cells can become long-lived memory cells and contribute to secondary immune responses. The precise signals that promote generation of long-lived memory NK cells are unknown. Using cytokine receptor-deficient mice, we show that interleukin-12 (IL-12) is indispensible for mouse cytomegalovirus (MCMV)-specific NK cell expansion and generation of memory NK cells. In contrast to wild-type NK cells that proliferated robustly and resided in lymphoid and nonlymphoid tissues for months after MCMV infection, IL-12 receptor–deficient NK cells failed to expand and were unable to mediate protection after MCMV challenge. We further demonstrate that a STAT4-dependent IFN-γ–independent mechanism contributes toward the generation of memory NK cells during MCMV infection. Understanding the full contribution of inflammatory cytokine signaling to the NK cell response against viral infection will be of interest for the development of vaccines and therapeutics. PMID:22493516

  14. Proinflammatory cytokine signaling required for the generation of natural killer cell memory.

    PubMed

    Sun, Joseph C; Madera, Sharline; Bezman, Natalie A; Beilke, Joshua N; Kaplan, Mark H; Lanier, Lewis L

    2012-05-07

    Although natural killer (NK) cells are classified as innate immune cells, recent studies demonstrate that NK cells can become long-lived memory cells and contribute to secondary immune responses. The precise signals that promote generation of long-lived memory NK cells are unknown. Using cytokine receptor-deficient mice, we show that interleukin-12 (IL-12) is indispensible for mouse cytomegalovirus (MCMV)-specific NK cell expansion and generation of memory NK cells. In contrast to wild-type NK cells that proliferated robustly and resided in lymphoid and nonlymphoid tissues for months after MCMV infection, IL-12 receptor-deficient NK cells failed to expand and were unable to mediate protection after MCMV challenge. We further demonstrate that a STAT4-dependent IFN-γ-independent mechanism contributes toward the generation of memory NK cells during MCMV infection. Understanding the full contribution of inflammatory cytokine signaling to the NK cell response against viral infection will be of interest for the development of vaccines and therapeutics.

  15. Oral administration of geraniol ameliorates acute experimental murine colitis by inhibiting pro-inflammatory cytokines and NF-κB signaling.

    PubMed

    Medicherla, Kanakaraju; Sahu, Bidya Dhar; Kuncha, Madhusudana; Kumar, Jerald Mahesh; Sudhakar, Godi; Sistla, Ramakrishna

    2015-09-01

    Ulcerative colitis is associated with a considerable reduction in the quality of life of patients. The use of phyto-ingredients is becoming an increasingly attractive approach for the management of colitis. Geraniol is a monoterpene with anti-inflammatory and antioxidative properties. In this study, we investigated the therapeutic potential of geraniol as a complementary and alternative medicine against dextran sulphate sodium (DSS)-induced ulcerative colitis in mice. Disease activity indices (DAI) comprising body weight loss, presence of occult blood and stool consistency were assessed for evaluation of colitis symptoms. Intestinal damage was assessed by evaluating colon length and its histology. Pre-treatment with geraniol significantly reduced the DAI score, improved stool consistency (without occult blood) and increased the colon length. The amount of pro-inflammatory cytokines, specifically TNF-α, IL-1β and IL-6 and the activity of myeloperoxidase in colon tissue were significantly decreased in geraniol pre-treated mice. Western blot analyses revealed that geraniol interfered with NF-κB signaling by inhibiting NF-κB (p65)-DNA binding, and IκBα phosphorylation, degradation and subsequent increase in nuclear translocation. Moreover, the expressions of downstream target pro-inflammatory enzymes such as iNOS and COX-2 were significantly reduced by geraniol. Pre-treatment with geraniol also restored the DSS-induced decline in antioxidant parameters such as reduced glutathione and superoxide dismutase activity and attenuated the increase in lipid peroxidation marker, thiobarbituric acid reactive substances and nitrative stress marker, nitrites in colon tissue. Thus, our results suggest that geraniol is a potential therapeutic agent for inflammatory bowel disease.

  16. ABCB5 maintains melanoma-initiating cells through a pro-inflammatory cytokine signaling circuit

    PubMed Central

    Wilson, Brian J.; Saab, Karim R.; Ma, Jie; Schatton, Tobias; Pütz, Pablo; Zhan, Qian; Murphy, George F.; Gasser, Martin; Waaga-Gasser, Ana Maria; Frank, Natasha Y.; Frank, Markus H.

    2014-01-01

    The drug efflux transporter ABCB5 identifies cancer stem-like cells (CSC) in diverse human malignancies, where its expression is associated with clinical disease progression and tumor recurrence. ABCB5 confers therapeutic resistance but other functions in tumorigenesis independent of drug efflux have not been described that might help explain why it is so broadly overexpressed in human cancer. Here we show that in melanoma-initiating cells ABCB5 controls IL-1β secretion which serves to maintain slow-cycling, chemoresistant cells through an IL-1β/IL8/CXCR1 cytokine signaling circuit. This CSC maintenance circuit involved reciprocal paracrine interactions with ABCB5-negative cancer cell populations. ABCB5 blockade induced cellular differentiation, reversed resistance to multiple chemotherapeutic agents, and impaired tumor growth in vivo. Together, our results defined a novel function for ABCB5 in CSC maintenance and tumor growth. PMID:24934811

  17. The signal transduction mediated by erythropoietin and proinflammatory cytokines in the JAK/STAT pathway in the children with cerebral palsy.

    PubMed

    Tao, Weiyuan; Wen, Fang; Zhang, Hong; Liu, Guheng

    2009-03-01

    It is well established that erythropoietin (EPO) is a pleiotropic cytokine, which has a brain-derived neuroprotective effect in the central nervous system (CNS). Immune abnormality has a close relationship with cerebral palsy (CP), and may be even involved in the development of CP. There is evidence that the amount of EPO in CP children is lower than in normal children, but the levels of proinflammatory cytokines, such as interleukin (IL)-6 and tumor necrosis factor (TNF)-alpha, are higher in the CP children. The signal transduction mediated by EPO that has a neuroprotective effect and mediated by proinflammatory cytokines that lead to brain damage shares the common JAK/STAT pathway. Under acute stress, the JAK/STAT pathway is occupied by massive proinflammatory cytokines, and the negative feedback inhibition factors like suppressor of cytokine signaling (SOCS) proteins are simultaneously activated, which exist in reciprocal inhibition to EPO in the JAK/STAT pathway. As a result, the signal transduction mediated by EPO is prevented or reduced, and the neuroprotective effect of EPO is eventually weakened. In this review, a novel approach to CP treatment through neurodevelopmental treatment (NDT) is put forward by analysis of the interrelationship of signal transduction mediated by EPO and proinflammatory cytokines in the JAK/STAT pathway and their roles in the development of CP, and some reasonable ideas for CP treatment are provided.

  18. Formal modelling of toll like receptor 4 and JAK/STAT signalling pathways: insight into the roles of SOCS-1, interferon-β and proinflammatory cytokines in sepsis.

    PubMed

    Paracha, Rehan Zafar; Ahmad, Jamil; Ali, Amjad; Hussain, Riaz; Niazi, Umar; Tareen, Samar Hayat Khan; Aslam, Babar

    2014-01-01

    Sepsis is one of the major causes of human morbidity and results in a considerable number of deaths each year. Lipopolysaccharide-induced sepsis has been associated with TLR4 signalling pathway which in collaboration with the JAK/STAT signalling regulate endotoxemia and inflammation. However, during sepsis our immune system cannot maintain a balance of cytokine levels and results in multiple organ damage and eventual death. Different opinions have been made in previous studies about the expression patterns and the role of proinflammatory cytokines in sepsis that attracted our attention towards qualitative properties of TLR4 and JAK/STAT signalling pathways using computer-aided studies. René Thomas' formalism was used to model septic and non-septic dynamics of TLR4 and JAK/STAT signalling. Comparisons among dynamics were made by intervening or removing the specific interactions among entities. Among our predictions, recurrent induction of proinflammatory cytokines with subsequent downregulation was found as the basic characteristic of septic model. This characteristic was found in agreement with previous experimental studies, which implicate that inflammation is followed by immunomodulation in septic patients. Moreover, intervention in downregulation of proinflammatory cytokines by SOCS-1 was found desirable to boost the immune responses. On the other hand, interventions either in TLR4 or transcriptional elements such as NFκB and STAT were found effective in the downregulation of immune responses. Whereas, IFN-β and SOCS-1 mediated downregulation at different levels of signalling were found to be associated with variations in the levels of proinflammatory cytokines. However, these predictions need to be further validated using wet laboratory experimental studies to further explore the roles of inhibitors such as SOCS-1 and IFN-β, which may alter the levels of proinflammatory cytokines at different stages of sepsis.

  19. Formal Modelling of Toll like Receptor 4 and JAK/STAT Signalling Pathways: Insight into the Roles of SOCS-1, Interferon-β and Proinflammatory Cytokines in Sepsis

    PubMed Central

    Paracha, Rehan Zafar; Ahmad, Jamil; Ali, Amjad; Hussain, Riaz; Niazi, Umar; Tareen, Samar Hayat Khan; Aslam, Babar

    2014-01-01

    Sepsis is one of the major causes of human morbidity and results in a considerable number of deaths each year. Lipopolysaccharide-induced sepsis has been associated with TLR4 signalling pathway which in collaboration with the JAK/STAT signalling regulate endotoxemia and inflammation. However, during sepsis our immune system cannot maintain a balance of cytokine levels and results in multiple organ damage and eventual death. Different opinions have been made in previous studies about the expression patterns and the role of proinflammatory cytokines in sepsis that attracted our attention towards qualitative properties of TLR4 and JAK/STAT signalling pathways using computer-aided studies. René Thomas’ formalism was used to model septic and non-septic dynamics of TLR4 and JAK/STAT signalling. Comparisons among dynamics were made by intervening or removing the specific interactions among entities. Among our predictions, recurrent induction of proinflammatory cytokines with subsequent downregulation was found as the basic characteristic of septic model. This characteristic was found in agreement with previous experimental studies, which implicate that inflammation is followed by immunomodulation in septic patients. Moreover, intervention in downregulation of proinflammatory cytokines by SOCS-1 was found desirable to boost the immune responses. On the other hand, interventions either in TLR4 or transcriptional elements such as NFκB and STAT were found effective in the downregulation of immune responses. Whereas, IFN-β and SOCS-1 mediated downregulation at different levels of signalling were found to be associated with variations in the levels of proinflammatory cytokines. However, these predictions need to be further validated using wet laboratory experimental studies to further explore the roles of inhibitors such as SOCS-1 and IFN-β, which may alter the levels of proinflammatory cytokines at different stages of sepsis. PMID:25255432

  20. Human resistin promotes neutrophil pro-inflammatory activation, neutrophil extracellular trap formation, and increases severity of acute lung injury

    PubMed Central

    Jiang, Shaoning; Park, Dae Won; Tadie, Jean-Marc; Gregoire, Murielle; Deshane, Jessy; Pittet, Jean Francois; Abraham, Edward; Zmijewski, Jaroslaw W.

    2014-01-01

    Although resistin was recently found to modulate insulin resistance in preclinical models of type II diabetes and obesity, recent studies have also suggested that resistin has proinflammatory properties. In these studies, we examined if the human specific variant of resistin affects neutrophil activation as well as the severity of LPS-induced acute lung injury (ALI). Because human and mouse resistin have distinct patterns of tissue distribution, experiments were performed using resistin humanized mice that exclusively express human resistin (hRTN+/−/−), but are deficient in mouse resistin. Enhanced production of TNF-α or MIP-2 was found in LPS-treated hRtn+/−/−, compared to control Rtn−/−/− neutrophils. Expression of human resistin inhibited the activation of AMP-activated protein kinase (AMPK), a major sensor and regulator of cellular bioenergetics that is also implicated in inhibiting inflammatory activity of neutrophils and macrophages. In addition to the ability of resistin to sensitize neutrophils to LPS stimulation, human resistin also enhanced neutrophil extracellular trap formation. In LPS-induced ALI, humanized resistin mice demonstrated enhanced production of pro-inflammatory cytokines, more severe pulmonary edema, increased NET formation, and elevated concentration of the alarmins HMGB1 and histone 3 in the lungs. Our results suggest that human resistin may play an important contributory role in enhancing TLR4 induced inflammatory responses, and may be a target for future therapies aimed at diminishing the severity of acute lung injury and other inflammatory situations where neutrophils play a major role. PMID:24719460

  1. Cinnamaldehyde inhibits pro-inflammatory cytokines secretion from monocytes/macrophages through suppression of intracellular signaling.

    PubMed

    Chao, Louis Kuoping; Hua, Kuo-Feng; Hsu, Hsien-Yeh; Cheng, Sen-Sung; Lin, I-Fan; Chen, Chia-Jung; Chen, Shui-Tein; Chang, Shang-Tzen

    2008-01-01

    We investigated the in vitro anti-inflammatory effects of Cinnamaldehyde, a cytokine production inhibitor isolated from an essential oil produced from the leaves of Cinnamomum osmophloeum Kaneh, and its mechanism of action. Although Cinnamaldehyde has been reported to have contact sensitizing properties at high concentration (mM), we found that low concentration of Cinnamaldehyde (muM) inhibited the secretion of interleukin-1beta and tumor necrosis factor alpha within lipopolysaccharide (LPS) or lipoteichoic acid (LTA) stimulated murine J774A.1 macrophages. Cinnamaldehyde also suppressed the production of these cytokines from LPS stimulated human blood monocytes derived primary macrophages and human THP-1 monocytes. Furthermore, Cinnamaldehyde also inhibited the production of prointerleukin-1beta within LPS or LTA stimulated human THP-1 monocytes. Reactive oxygen species release from LPS stimulated J774A.1 macrophages was reduced by Cinnamaldehyde. The phosphorylation of extracellular signal-regulated kinase 1/2 and c-Jun N-terminal kinase 1/2 induced by LPS was also inhibited by Cinnamaldehyde; however, Cinnamaldehyde neither antagonize the binding of LPS to the cells nor alter the cell surface expression of toll-like receptor 4 and CD14. In addition, we also noted that Cinnamaldehyde appeared to elicit no cytotoxic effect upon J774A.1 macrophages under our experimental conditions, although Cinnamaldehyde reduced J774A.1 macrophages proliferation as analysed by MTT assay. Our current results have demonstrated the anti-oxidation and anti-inflammatory properties of Cinnamaldehyde that could provide the possibility for Cinnamaldehyde's future pharmaceutical application in the realm of immuno-modulation.

  2. Memory deficit associated with increased brain proinflammatory cytokine levels and neurodegeneration in acute ischemic stroke.

    PubMed

    Silva, Bruno; Sousa, Larissa; Miranda, Aline; Vasconcelos, Anilton; Reis, Helton; Barcelos, Lucíola; Arantes, Rosa; Teixeira, Antonio; Rachid, Milene Alvarenga

    2015-08-01

    The present study aimed to investigate behavioral changes and neuroinflammatory process following left unilateral common carotid artery occlusion (UCCAO), a model of cerebral ischemia. Post-ischemic behavioral changes following 15 min UCCAO were recorded 24 hours after reperfusion. The novel object recognition task was used to assess learning and memory. After behavioral test, brains from sham and ischemic mice were removed and processed to evaluate central nervous system pathology by TTC and H&E techniques as well as inflammatory mediators by ELISA. UCCAO promoted long-term memory impairment after reperfusion. Infarct areas were observed in the cerebrum by TTC stain. Moreover, the histopathological analysis revealed cerebral necrotic cavities surrounded by ischemic neurons and hippocampal neurodegeneration. In parallel with memory dysfunction, brain levels of TNF-a, IL-1b and CXCL1 were increased post ischemia compared with sham-operated group. These findings suggest an involvement of central nervous system inflammatory mediators and brain damage in cognitive impairment following unilateral acute ischemia.

  3. High-Mobility Group Box-1 Induces Proinflammatory Cytokines Production of Kupffer Cells through TLRs-Dependent Signaling Pathway after Burn Injury

    PubMed Central

    Chen, Xu-Lin; Sun, Li; Guo, Feng; Wang, Fei; Liu, Sheng; Liang, Xun; Wang, Ren-Su; Wang, Yong-Jie; Sun, Ye-Xiang

    2012-01-01

    Kupffer cells (KCs) were a significant source of cytokine release during the early stage of severe burns. High mobility group box protein 1 (HMGB1) was recently identified as a new type of proinflammatory cytokine. The ability of HMGB1 to generate inflammatory responses after burn trauma has not been well characterized. KCs were isolated from sham animals and rats with a 30% full-thickness burn, and then were stimulated with increasing concentrations of HMGB1. The levels of Tumor necrosis factor (TNF)-α and interleukin (IL)-1β in culture supernatant were measured by enzyme-linked immunosorbent assay. Northern blot analysis was performed to detect the expressions of TNF-α and IL-1β mRNAs. The activities of p38 MAPK and JNK (by Western blot analysis) as well as NF-κB (by EMSA) in KCs were also examined. As a result, HMGB1 in vitro upregulated expressions of TNF-α and IL-1β of KCs in a dose-dependent manner, and HMGB1 promoted KCs from burn rats to produce significantly more TNF-α and IL-1β proteins than those from sham animals. After harvested from burn rats, KCs were pre-incubated with anti-TLR2 or anti-TLR4 antibody prior to HMGB1 administration. HMGB1 exposure not only significantly increased expressions of TNF-α and IL-1β mRNAs in KCs from burn rats, but also enhanced activities of p38 MAPK, JNK and NF-κB. However, these upregulation events were all reduced by pre-incubation with anti-TLR2 or anti-TLR4 antibody. These results indicate that HMGB1 induces proinflammatory cytokines production of KCs after sever burn injury, and this process might be largely dependent on TLRs-dependent MAPKs/NF-κB signal pathway. PMID:23209806

  4. The pro-inflammatory signalling regulator Stat4 promotes vasculogenesis of great vessels derived from endothelial precursors

    PubMed Central

    Meng, Zhao-Zheng; Liu, Wei; Xia, Yu; Yin, Hui-Min; Zhang, Chi-Yuan; Su, Dan; Yan, Li-Feng; Gu, Ai-Hua; Zhou, Yong

    2017-01-01

    Vasculogenic defects of great vessels (GVs) are a major cause of congenital cardiovascular diseases. However, genetic regulators of endothelial precursors in GV vasculogenesis remain largely unknown. Here we show that Stat4, a transcription factor known for its regulatory role of pro-inflammatory signalling, promotes GV vasculogenesis in zebrafish. We find stat4 transcripts highly enriched in nkx2.5+ endothelial precursors in the pharynx and demonstrate that genetic ablation of stat4 causes stenosis of pharyngeal arch arteries (PAAs) by suppressing PAAs 3–6 angioblast development. We further show that stat4 is a downstream target of nkx2.5 and that it autonomously promotes proliferation of endothelial precursors of the mesoderm. Mechanistically, stat4 regulates the emerging PAA angioblasts by inhibiting the expression of hdac3 and counteracting the effect of stat1a. Altogether, our study establishes a role for Stat4 in zebrafish great vessel development, and suggests that Stat4 may serve as a therapeutic target for GV defects. PMID:28256502

  5. IL-21 modulates release of proinflammatory cytokines in LPS-stimulated macrophages through distinct signaling pathways.

    PubMed

    Li, Su-nan; Wang, Wei; Fu, Shou-peng; Wang, Jian-fa; Liu, Hong-mei; Xie, Shan-shan; Liu, Bing-run; Li, Yang; Lv, Qing-kang; Li, Zhi-qiang; Xue, Wen-jing; Huang, Bing-xu; Chen, Wei; Liu, Ju-xiong

    2013-01-01

    The aim of this study was to investigate the anti-inflammatory effect of IL-21 on LPS-induced mouse peritoneal macrophages. The results showed that IL-21 significantly inhibited LPS-induced mRNA expression of IL-1β, TNF-α, and IL-6 in macrophages, but not of IFN-γ, IL-10, CCL5, or CXCL2. ELISA analysis showed that IL-21 also suppressed LPS-induced production of TNF-α and IL-6 in culture supernatants. Western blot analysis showed that IL-21 clearly inhibited ERK and IκBα phosphorylation and NF-κB translocation in LPS-stimulated macrophages, but it increased STAT3 phosphorylation. Flow cytometric and Western blot analysis showed that IL-21 decreased M1 macrophages surface markers expression of CD86, iNOS, and TLR4 in LPS-stimulated cells. All results suggested that IL-21 decreases IL-6 and TNF-α production via inhibiting the phosphorylation of ERK and translocation of NF-κB and promotes a shift from the M1 to M2 macrophage phenotype by decreasing the expression of CD86, iNOS, and TLR4 and by increasing STAT3 phosphorylation in LPS-stimulated cells.

  6. Pro-inflammatory cytokines expression increases following low- and high-magnitude cyclic loading of lumbar ligaments

    PubMed Central

    D’Ambrosia, Peter; King, Karen; Davidson, Bradley; Zhou, Bing He; Lu, Yun

    2010-01-01

    Repetitive or overuse disorders of the lumbar spine affect the lives of workers and athletes. We hypothesize that repetitive anterior lumbar flexion–extension under low or high load will result in significantly elevated pro-inflammatory cytokines expression several hours post-activity. High loads will exhibit significantly higher expression than low loads. Lumbar spine of in vivo feline was subjected to cyclic loading at 0.25 Hz for six 10-min periods with 10 min of rest in between. One group was subjected to a low peak load of 20 N, whereas the second group to a high peak load of 60 N. Following a 7-h post-loading rest, the supraspinous ligaments of L-3/4, L-4/5 and L-5/6 and the unstimulated T-10/11 were excised for mRNA analysis and IL-1β, IL-6, IL-8, TNFα and TGFβ1 pro-inflammatory cytokines expression. Creep (laxity) developed in the lumbar spine during the loading and the subsequent 7 h of rest was calculated. A two-way mixed model ANOVA was used to assess difference in each cytokines expression between the two groups and control. Tukey HSD post hoc analysis delineated specific significant effects. Significance was set at 0.05. Low and high-load groups exhibited development of creep throughout the cyclic loading period and gradual recovery throughout the 7-h rest period. Residual creep of 24.8 and 30.2% were present in the low and high-load groups, respectively, 7-h post-loading. Significant increases in expression of all cytokines measured relative to control were obtained for supraspinous ligaments from both low and high-load magnitudes. IL-6, IL-8 and TGFβ1 expression in the high-load group were significantly higher relative to the low-load group. Significant increases in cytokines expression indicating tissue inflammation are observed several hours post-repetitive lumbar flexion–extension regardless of the load magnitude applied. Repetitive occupational and athletic activity, regardless of the load applied, may be associated with the

  7. Activation of adult rat CNS endothelial cells by opioid-induced toll-like receptor 4 (TLR4) signaling induces proinflammatory, biochemical, morphological, and behavioral sequelae

    PubMed Central

    Grace, Peter M.; Ramos, Khara M.; Rodgers, Krista M.; Wang, Xiaohui; Hutchinson, Mark R.; Lewis, Makenzie T.; Morgan, Kelly N.; Kroll, Juliet L.; Taylor, Frederick R.; Strand, Keith A.; Zhang, Yingning; Berkelhammer, Debra; Huey, Madeline G.; Greene, Lisa I.; Cochran, Thomas A.; Yin, Hang; Barth, Daniel S.; Johnson, Kirk W.; Rice, Kenner; Maier, Steven F.; Watkins, Linda R.

    2014-01-01

    CNS immune signaling contributes to deleterious opioid effects including hyperalgesia, tolerance, reward, and dependence/withdrawal. Such effects are mediated by opioid signaling at TLR4, presumptively of glial origin. Whether CNS endothelial cells express TLR4 is controversial. If so, they would be well positioned for activation by blood-borne opioids, contributing to opioid-induced pro-inflammatory responses. These studies examined adult primary rat CNS endothelial cell responses to (-)-morphine or its mu-opioid receptor (MOR) inactive metabolite morphine-3-glucuronide (M3G), both known TLR4 agonists. We demonstrate that adult rat CNS endothelial cells express functional TLR4. M3G activated NFκB, increased tumor necrosis factor-α (TNFα) and cyclooxygenase-2 (COX2) mRNAs, and released prostaglandin E2 from these cells. (-)-Morphine-induced upregulation of TNFα mRNA and prostaglandin E2 release were unmasked by pre-treatment with nalmefene, a MOR antagonist without TLR4 activity (unlike CTAP, shown to have both MOR- and TLR4-activity), suggestive of an interplay between MOR and TLR4 co-activation by (-)-morphine. In support, MOR-dependent Protein Kinase A (PKA) opposed TLR4 signaling, as PKA inhibition (H-89) also unmasked (-)-morphine-induced TNFα and COX2 mRNA upregulation. Intrathecal injection of CNS endothelial cells, stimulated in vitro with M3G, produced TLR4-dependent tactile allodynia. Further, cortical suffusion with M3G in vivo induced TLR4-dependent vasodilation. Finally, endothelial cell TLR4 activation by lipopolysaccharide and/or M3G was blocked by the glial inhibitors AV1013 and propentofylline, demonstrating endothelial cells as a new target of such drugs. These data indicate that (-)-morphine and M3G can activate CNS endothelial cells via TLR4, inducing proinflammatory, biochemical, morphological, and behavioral sequalae. CNS endothelial cells may have previously unanticipated roles in opioid-induced effects, in phenomena blocked by

  8. Adenosine A2A receptor signaling attenuates LPS-induced pro-inflammatory cytokine formation of mouse macrophages by inducing the expression of DUSP1.

    PubMed

    Köröskényi, Krisztina; Kiss, Beáta; Szondy, Zsuzsa

    2016-07-01

    Adenosine is known to reduce inflammation by suppressing the activity of most immune cells. Previous studies have shown that lipopolysaccharide (LPS) stimulated mouse macrophages produce adenosine, and the adenosine A2A receptor (A2AR) signaling activated in an autocrine manner attenuates LPS-induced pro-inflammatory cytokine formation. It has been suggested that A2AR signaling inhibits LPS-induced pro-inflammatory cytokine production through a unique cAMP-dependent, but PKA- and Epac-independent signaling pathway. However, the mechanism of inhibition was not identified so far. Here we report that LPS stimulation enhances A2AR expression in mouse bone marrow derived macrophages, and loss of A2ARs results in enhanced LPS-induced pro-inflammatory response. Loss of A2ARs in A2AR null macrophages did not alter the LPS-induced NF-κB activation, but an enhanced basal and LPS-induced phosphorylation of MAP kinases (especially that of JNKs) was detected in A2AR null cells. A2AR signaling did not alter the LPS-induced phosphorylation of their upstream kinases, but by regulating adenylate cyclase activity it enhanced the expression of dual specific phosphatase (DUSP)1, a negative regulator of MAP kinases. As a result, lower basal and LPS-induced DUSP1 mRNA and protein levels can be detected in A2AR null macrophages. Silencing of DUSP1 mRNA expression resulted in higher basal and LPS-induced JNK phosphorylation and LPS-induced pro-inflammatory cytokine formation in wild type macrophages, but had no effect on that in A2AR null cells. Our data indicate that A2AR signaling regulates both basal and LPS-induced DUSP1 levels in macrophages via activating the adenylate cyclase pathway.

  9. Dysfunctional Pro-Inflammatory High Density Lipoproteins Confer Increased Risk for Atherosclerosis in Women with Systemic Lupus Erythematosus

    PubMed Central

    McMahon, Maureen; Grossman, Jennifer; Skaggs, Brian; FitzGerald, John; Sahakian, Lori; Ragavendra, Nagesh; Charles-Schoeman, Christina; Watson, Karol; Wong, Weng Kee; Chen, Weiling; Gorn, Alan; Karpouzas, George; Weisman, Michael; Wallace, Daniel J.; Hahn, Bevra H.

    2009-01-01

    Objective Women with systemic lupus erythematosus (SLE) have increased atherosclerosis. Identification of at-risk patients and the etiology underlying atherosclerosis in SLE remains elusive. Normal HDL lose antioxidant capacity during inflammation, and these dysfunctional HDL might predispose to atherosclerosis. The aim of this study is to determine whether dysfunctional pro-inflammatory HDL (piHDL) is associated with subclinical atherosclerosis in SLE. Methods 276 SLE women had carotid artery ultrasound to identify plaques and measure intima-media thickness (IMT). Antioxidant function of HDL was measured as change in oxidation of LDL after addition of subject HDL. Two anti-inflammatory HDL components, paraoxonase and apolipoprotein A-1, were also measured. Results 48.2% of patients had piHDL. 86.7% of subjects with plaque had piHDL, versus 40.7% without (p<0.001). Patients with piHDL also had higher IMT (p<0.001). After multivariate analysis, the only significant factors associated with plaque were piHDL, (OR 16.1, p<0.001), age (OR 1.2, p<0.001), hypertension (OR 3.0, p=0.04), dyslipidemia (OR 3.4, p=0.04), and mixed racial background (OR 8.3, p=0.04). Factors associated with IMT measurements in the highest quartile were piHDL (OR 2.5, p=0.02), age (OR 1.1, p<0.001), body mass index (OR 1.07, p=0.04), lifetime prednisone dose > 20g (OR 2.8, p=0.04), and African American race (OR 8.3, p=0.001). Conclusions Dysfunctional piHDL greatly increases risk for subclinical atherosclerosis in SLE; they associate with increased prevalence of carotid plaque and with high IMT. The presence of piHDL may help identify patients at risk for atherosclerosis. PMID:19644959

  10. Mitochondrial substrate availability and its role in lipid-induced insulin resistance and proinflammatory signaling in skeletal muscle.

    PubMed

    Lipina, Christopher; Macrae, Katherine; Suhm, Tamara; Weigert, Cora; Blachnio-Zabielska, Agnieszka; Baranowski, Marcin; Gorski, Jan; Burgess, Karl; Hundal, Harinder S

    2013-10-01

    The relationship between glucose and lipid metabolism has been of significant interest in understanding the pathogenesis of obesity-induced insulin resistance. To gain insight into this metabolic paradigm, we explored the potential interplay between cellular glucose flux and lipid-induced metabolic dysfunction within skeletal muscle. Here, we show that palmitate (PA)-induced insulin resistance and proinflammation in muscle cells, which is associated with reduced mitochondrial integrity and oxidative capacity, can be attenuated under conditions of glucose withdrawal or glycolytic inhibition using 2-deoxyglucose (2DG). Importantly, these glucopenic-driven improvements coincide with the preservation of mitochondrial function and are dependent on PA oxidation, which becomes markedly enhanced in the absence of glucose. Intriguingly, despite its ability to upregulate mitochondrial PA oxidation, glucose withdrawal did not attenuate PA-induced increases in total intramyocellular diacylglycerol and ceramide. Furthermore, consistent with our findings in cultured muscle cells, we also report enhanced insulin sensitivity and reduced proinflammatory tone in soleus muscle from obese Zucker rats fed a 2DG-supplemented diet. Notably, this improved metabolic status after 2DG dietary intervention is associated with markedly reduced plasma free fatty acids. Collectively, our data highlight the key role that mitochondrial substrate availability plays in lipid-induced metabolic dysregulation both in vitro and in vivo.

  11. Cervicovaginal levels of proinflammatory cytokines are increased during chlamydial infection in bacterial vaginosis but not in lactobacilli-dominated flora.

    PubMed

    Marconi, Camila; Santos-Greatti, Mariana M V; Parada, Cristina M G L; Pontes, Anagloria; Pontes, Ana G; Giraldo, Paulo C; Donders, Gilbert G G; da Silva, Márcia Guimarães

    2014-07-01

    The purpose of this study was to assess the cervicovaginal levels of proinflammatory cytokines in women with Chlamydia trachomatis (CT) infection in the presence of bacterial vaginosis (BV) and normal flora and to compare with those negative for CT. In this cross-sectional study, nonpregnant women were enrolled at 2 outpatient clinics and at 1 primary medical care unit in São Paulo State, Brazil. Cervicovaginal samples from 256 women with BV, of which 68 (26.6%) had concomitant CT infection and 188 (73.4%) were CT-negative, were measured for interleukin-1β (IL-1β), IL-6, and IL-8 by enzyme-linked immunosorbent assay. A matching number of samples from women with normal flora, CT-positive (n = 68) and negative (n = 188), were evaluated as control. Cytokine levels were compared by Mann-Whitney test and differences were considered significant at p < .05. In CT-negative women, IL-1β was increased in BV (p < .001) when compared to normal flora, while the levels of IL-6 and IL8 were unchanged. The presence of CT infection was not associated with differences on cytokine levels in women with normal flora. However, women with BV had higher levels of IL-1β (p = .02), IL-6 (p = .02), and IL-8 (p = .03) in the presence of CT when compared to those who tested negative for CT. Detection of endocervical CT is associated with increased cervicovaginal IL-1β, IL-6, and IL-8 levels in women with concomitant BV but not in those with normal flora.

  12. Transmembrane TNF-α Reverse Signaling Inhibits Lipopolysaccharide-Induced Proinflammatory Cytokine Formation in Macrophages by Inducing TGF-β: Therapeutic Implications.

    PubMed

    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.

  13. Endometritis Increases Pro-inflammatory Cytokines in Follicular Fluid and Cervico-vaginal Mucus in the Buffalo Cow.

    PubMed

    Boby, Jones; Kumar, Harendra; Gupta, Harihar Prasad; Jan, Mustapha Hussain; Singh, Sanjay Kumar; Patra, Manas Kumar; Nandi, Sukdeb; Abraham, Asha; Krishnaswamy, Narayanan

    2016-11-17

    Emerging evidence shows that some of the pro-inflammatory cytokines are elevated not only in the endometrium but also in the follicular fluid of cows with endometritis. Developing a cervico-vaginal mucus (CVM) based test has the potential for becoming a pen-side test because of the ease of sample collection. The present study describes the results of two different experiments. The first experiment was conducted to investigate the influence of endometritis on the proinflammatory cytokines of follicular fluid based on the reproductive tracts of buffalo collected at a slaughter house Buffalo genitalia were categorized into purulent endometritis (PE), cytological endometritis (CE), and non-endometritis (NE) based on the white-side test and endometrial cytology, respectively (n = 14/group). Each group was subdivided into follicular and mid-luteal stage (n = 7/stage) and the follicular fluid was collected from the largest follicle. Second experiment was done to study the difference in the levels of proinflammatory cytokines in the CVM of repeat breeders with subclinical endometritis presented to the clinic. CVM was collected from the repeaters (n = 10) and non-repeaters (n = 10) through aseptic trans-vaginal aspiration. The pro-inflammatory cytokines such as IL-1β, IL-6, IL-8, and TNFα were quantitated through bovine specific ELISA kits. Significantly higher concentrations of pro-inflammatory cytokines (IL-1β, IL-8, IL-6, and TNFα) along with low intra-follicular estradiol in buffaloes of PE and CE groups suggest that endometritis impedes the follicular steroidogenesis. Significantly higher concentration of IL-1β and TNF-α in the CVM of repeaters indicate their potential as a pen-side diagnostic test for CE.

  14. HMGB1/TLR Receptor Danger Signaling Increases Brain Neuroimmune Activation in Alcohol Dependence

    PubMed Central

    Crews, Fulton T.; Qin, Liya; Sheedy, Donna; Vetreno, Ryan P.; Zou, Jian

    2012-01-01

    Background Innate immune gene expression is regulated in part through high mobility group box 1(HMGB1), an endogenous proinflammatory cytokine, that activates multiple members of the interleukin-1/Toll-like receptor (IL-1/TLR) family associated with danger signaling. We investigated expression of HMGB1, TLR2, TLR3 and TLR4 in chronic ethanol treated mouse brain, post-mortem human alcoholic brain, and rat brain slice culture to test the hypothesis that neuroimmune activation in alcoholic brain involves ethanol activation of HMGB1/TLR danger signaling. Methods Protein levels were assessed using Western blot, ELISA, immunohistochemical immunoreactivity (+IR), and mRNA levels were measured by real time PCR in ethanol-treated mice (5 g/kg/day, i.g., 10 days + 24 hr), rat brain slice culture, and post-mortem human alcoholic brain. Results Ethanol treatment of mice increased brain mRNA and +IR protein expression of HMGB1, TLR2, TLR3, and TLR4. Post-mortem human alcoholic brain also showed increased HMGB1, TLR2, TLR3, and TLR4+IR cells that correlated with lifetime alcohol consumption as well as each other. Ethanol treatment of brain slice culture released HMGB1 into the media and induced the proinflammatory cytokine, IL-1β. Neutralizing antibodies to HMGB1 and small inhibitory mRNA to HMGB1 or TLR4 blunted ethanol induction of IL-1β. Conclusions Ethanol-induced HMGB1/TLR signaling contributes to induction of the proinflammatory cytokine, IL-1β. Increased expression of HMGB1, TLR2, TLR3, and TLR4 in alcoholic brain and in mice treated with ethanol suggests that chronic alcohol-induced brain neuroimmune activation occurs through HMGB1/TLR signaling. PMID:23206318

  15. A pro-inflammatory diet is associated with increased risk of developing hypertension among middle-aged women.

    PubMed

    Vissers, L E T; Waller, M; van der Schouw, Y T; Hébert, J R; Shivappa, N; Schoenaker, D A J M; Mishra, G D

    2017-06-01

    A pro-inflammatory diet is thought to lead to hypertension through oxidative stress and vessel wall inflammation. We therefore investigated the association between the dietary inflammatory index (DII) and developing hypertension in a population-based cohort of middle-aged women. The Australian Longitudinal Study on Women's Health included 7169 Australian women, aged 52 years (SD 1 year) at baseline in 2001, who were followed up through 4 surveys until 2013. The DII, a literature-derived dietary index that has been validated against several inflammatory markers, was calculated based on data collected via a validated food-frequency questionnaire administered at baseline. Hypertension was defined as new onset of doctor-diagnosed hypertension, ascertained through self-report between 2001 and 2013. Generalised Estimating Equation analyses were used to investigate the association between the DII and incident hypertension. The analyses were adjusted for demographic and hypertension risk factors. During 12-years follow-up we identified 1680 incident cases of hypertension. A more pro-inflammatory diet was associated with higher risk of hypertension in dichotomised analyses with an ORfully adjusted of 1.24, 95% CI: 1.06-1.45. A pro-inflammatory diet might lead to a higher risk of developing hypertension. These results need to be replicated in other studies. Copyright © 2017. Published by Elsevier B.V.

  16. Transient Receptor Potential Channel 1 Deficiency Impairs Host Defense and Proinflammatory Responses to Bacterial Infection by Regulating Protein Kinase Cα Signaling

    PubMed Central

    Zhou, Xikun; Ye, Yan; Sun, Yuyang; Li, Xuefeng; Wang, Wenxue; Privratsky, Breanna; Tan, Shirui; Zhou, Zongguang; Huang, Canhua; Wei, Yu-Quan; Birnbaumer, Lutz

    2015-01-01

    Transient receptor potential channel 1 (TRPC1) is a nonselective cation channel that is required for Ca2+ homeostasis necessary for cellular functions. However, whether TRPC1 is involved in infectious disease remains unknown. Here, we report a novel function for TRPC1 in host defense against Gram-negative bacteria. TRPC1−/− mice exhibited decreased survival, severe lung injury, and systemic bacterial dissemination upon infection. Furthermore, silencing of TRPC1 showed decreased Ca2+ entry, reduced proinflammatory cytokines, and lowered bacterial clearance. Importantly, TRPC1 functioned as an endogenous Ca2+ entry channel critical for proinflammatory cytokine production in both alveolar macrophages and epithelial cells. We further identified that bacterium-mediated activation of TRPC1 was dependent on Toll-like receptor 4 (TLR4), which induced endoplasmic reticulum (ER) store depletion. After activation of phospholipase Cγ (PLC-γ), TRPC1 mediated Ca2+ entry and triggered protein kinase Cα (PKCα) activity to facilitate nuclear translocation of NF-κB/Jun N-terminal protein kinase (JNK) and augment the proinflammatory response, leading to tissue damage and eventually mortality. These findings reveal that TRPC1 is required for host defense against bacterial infections through the TLR4-TRPC1-PKCα signaling circuit. PMID:26031335

  17. Pinellia ternata lectin exerts a pro-inflammatory effect on macrophages by inducing the release of pro-inflammatory cytokines, the activation of the nuclear factor-κB signaling pathway and the overproduction of reactive oxygen species.

    PubMed

    Yu, Hong-Li; Zhao, Teng-Fei; Wu, Hao; Pan, Yao-Zong; Zhang, Qian; Wang, Kui-Long; Zhang, Chen-Chao; Jin, Yang-Ping

    2015-10-01

    Pinellia ternata (PT) is a widely used traditional Chinese medicine. The raw material has a throat-irritating toxicity that is associated with the PT lectin (PTL). PTL is a monocot lectin isolated from the tubers of PT, which exhibits mouse peritoneal acute inflammatory effects in vivo. The present study aimed to investigate the pro-inflammatory effect of PTL on macrophages. PTL (50 µg/ml)‑stimulated macrophages enhanced the chemotactic activity of neutrophils. PTL (50, 100, 200 and 400 µg/ml) significantly elevated the production of cytokines [tumor necrosis factor‑α (TNF-α) , interleukin (IL)‑1β and IL‑6]. PTL (25, 50 and 100 µg/ml) induced intracellular reactive oxygen species (ROS) overproduction. PTL also caused transfer of p65 from the macrophage cytoplasm to the nucleus and activated the nuclear factor‑κB (NF‑κB) signaling pathway. Scanning electron microscope images revealed severe cell swelling and membrane integrity defection of macrophages following PTL (100 µg/ml) stimulation, which was also associated with inflammation. PTL had pro‑inflammatory activity, involving induced neutrophil migration, cytokine release, ROS overproduction and the activation of the NF-κB signaling pathway, which was associated with the activation of macrophages.

  18. Crocin Inhibits Oxidative Stress and Pro-inflammatory Response of Microglial Cells Associated with Diabetic Retinopathy Through the Activation of PI3K/Akt Signaling Pathway.

    PubMed

    Yang, Xinguang; Huo, Fuquan; Liu, Bei; Liu, Jing; Chen, Tao; Li, Junping; Zhu, Zhongqiao; Lv, Bochang

    2017-02-25

    Diabetic retinopathy (DR) is a serious microvascular complication of diabetes mellitus that is closely associated with the degeneration and loss of retinal ganglion cells (RGCs) caused by diabetic microangiopathy and subsequent oxidative stress and an inflammatory response. Microglial cells are classed as neurogliocytes and play a significant role in neurodegenerative diseases. Over-activated microglial cells may cause neurotoxicity and induce the death and apoptosis of RGCs. Crocin is one of the two most pharmacologically bioactive constituents in saffron. In the present study, we focused on the role of microglial cells in DR, suggesting that DR may cause the over-activation of microglial cells and induce oxidative stress and the release of pro-inflammatory factors. Microglial cells BV-2 and N9 were cultured, and high-glucose (HG) and free fatty acid (FFA) were used to simulate diabetes. The results showed that HG-FFA co-treatment caused the up-regulated expression of CD11b and Iba-1, indicating that BV-2 and N9 cells were over-activated. Moreover, oxidative stress markers and pro-inflammatory factors were significantly enhanced by HG-FFA treatment. We found that crocin prevented the oxidative stress and pro-inflammatory response induced by HG-FFA co-treatment. Moreover, using the PI3K/Akt inhibitor LY294002, we revealed that PI3K/Akt signaling plays a significant role in blocking oxidative stress, suppressing the pro-inflammatory response, and maintaining the neuroprotective effects of crocin. In total, these results provide a new insight into DR and DR-induced oxidative stress and the inflammatory response, which provide a potential therapeutic target for neuronal damage, vision loss, and other DR-induced complications.

  19. Adverse Husbandry of Maraena Whitefish Directs the Immune System to Increase Mobilization of Myeloid Cells and Proinflammatory Responses

    PubMed Central

    Korytář, Tomáš; Nipkow, Mareen; Altmann, Simone; Goldammer, Tom; Köllner, Bernd; Rebl, Alexander

    2016-01-01

    Adverse life circumstances evoke a common “conserved transcriptional response to adversity” (CTRA) in mammalian leukocytes. To investigate whether this pattern is preserved in lower vertebrates, maraena whitefish (Coregonus maraena) were exposed for 9 days to different stocking densities: ~10 kg/m3 (low density), ~33 kg/m3 (moderate), ~60 kg/m3 (elevated), and ~100 kg/m3 (high). Transcriptome profiling in the liver and kidney of individuals from each group suggested that crowding conditions activate stress-related signaling and effector pathways. Remarkably, about one-quarter of the genes differentially expressed under crowding conditions were involved in the activation of immune pathways such as acute-phase response and interleukin/TNF signaling attended by the simultaneous reduction of antiviral potency. Network analysis confirmed the complex interdigitation of immune- and stress-relevant pathways with interleukin-1 playing a central role. Antibody-based techniques revealed remarkable changes in the blood composition of whitefish and demonstrated the correlation between increasing stocking densities and elevated number of myeloid cells together with the increased phagocytic activity of peripheral blood leukocytes. In line with current studies in mammals, we conclude that crowding stress triggers in whitefish hallmarks of a CTRA, indicating that the stress-induced molecular mechanisms regulating the immune responses not only are conserved within mammals but were established earlier in evolution. PMID:28066440

  20. Human herpesvirus 6A infection in CD46 transgenic mice: viral persistence in the brain and increased production of proinflammatory chemokines via Toll-like receptor 9.

    PubMed

    Reynaud, Joséphine M; Jégou, Jean-François; Welsch, Jérémy C; Horvat, Branka

    2014-05-01

    Human herpesvirus 6 (HHV-6) is widely spread in the human population and has been associated with several neuroinflammatory diseases, including multiple sclerosis. To develop a small-animal model of HHV-6 infection, we analyzed the susceptibility of several lines of transgenic mice expressing human CD46, identified as a receptor for HHV-6. We showed that HHV-6A (GS) infection results in the expression of viral transcripts in primary brain glial cultures from CD46-expressing mice, while HHV-6B (Z29) infection was inefficient. HHV-6A DNA persisted for up to 9 months in the brain of CD46-expressing mice but not in the nontransgenic littermates, whereas HHV-6B DNA levels decreased rapidly after infection in all mice. Persistence in the brain was observed with infectious but not heat-inactivated HHV-6A. Immunohistological studies revealed the presence of infiltrating lymphocytes in periventricular areas of the brain of HHV-6A-infected mice. Furthermore, HHV-6A stimulated the production of a panel of proinflammatory chemokines in primary brain glial cultures, including CCL2, CCL5, and CXCL10, and induced the expression of CCL5 in the brains of HHV-6A-infected mice. HHV-6A-induced production of chemokines in the primary glial cultures was dependent on the stimulation of toll-like receptor 9 (TLR9). Finally, HHV-6A induced signaling through human TLR9 as well, extending observations from the murine model to human infection. Altogether, this study presents a first murine model for HHV-6A-induced brain infection and suggests a role for TLR9 in the HHV-6A-initiated production of proinflammatory chemokines in the brain, opening novel perspectives for the study of virus-associated neuropathology. HHV-6 infection has been related to neuroinflammatory diseases; however, the lack of a suitable small-animal infection model has considerably hampered further studies of HHV-6-induced neuropathogenesis. In this study, we have characterized a new model for HHV-6 infection in mice

  1. Maternal warmth buffers the effects of low early-life socioeconomic status on pro-inflammatory signaling in adulthood.

    PubMed

    Chen, E; Miller, G E; Kobor, M S; Cole, S W

    2011-07-01

    The notion that family support may buffer individuals under adversity from poor outcomes has been theorized to have important implications for mental and physical health, but little is known about the biological mechanisms that explain these links. We hypothesized that adults who grew up in low socioeconomic status (SES) households but who experienced high levels of maternal warmth would be protected from the pro-inflammatory states typically associated with low SES. A total of 53 healthy adults (aged 25-40 years) low in SES early in life were assessed on markers of immune activation and systemic inflammation. Genome-wide transcriptional profiling also was conducted. Low early-life SES individuals who had mothers, who expressed high warmth toward them, exhibited less Toll-like receptor-stimulated production of interleukin 6, and reduced bioinformatic indications of pro-inflammatory transcription factor activity (NF-κB) and immune activating transcription factor activity (AP-1) compared to those who were low in SES early in life but experienced low maternal warmth. To the extent that such effects are causal, they suggest the possibility that the detrimental immunologic effects of low early-life SES environments may be partly diminished through supportive family climates.

  2. Crosstalk between signals initiated from TLR4 and cell surface BAFF results in synergistic induction of proinflammatory mediators in THP-1 cells

    PubMed Central

    Lim, Su-Geun; Kim, Jae-Kwan; Suk, Kyoungho; Lee, Won-Ha

    2017-01-01

    Cellular response to stimulation is mediated by meshwork of signaling pathways that may share common signaling adaptors. Here, we present data demonstrating that signaling pathways initiated from the membrane-bound form of B-cell activating factor (BAFF) can crosstalk with lipopolysaccharide (LPS)-induced signaling for synergistic expression of proinflammatory mediators in the human macrophage-like cell line THP-1. Co-treatment of the cells with BAFF-specific monoclonal antibody and LPS resulted in enhanced mitogen-activated protein kinase (MAPK)/mitogen- and stress-activated protein kinase (MSK)-mediated phosphorylation of nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) p65 subunit (Ser276), which then interacts with CREB binding protein (CBP) for subsequent acetylation. Simultaneously, the phosphorylation of cyclic AMP-response element binding protein (CREB) was enhanced through the combined action of phosphatidylinositol-3-kinase (PI3K)/AKT and MAPK/MSK pathways, and the resulting phospho-CREB interacted with the NF-κB/CBP complex. Transfection of CREB-specific siRNA inhibited the BAFF-mediated enhancing effect indicating that the formation of the CREB/NF-κB/CBP complex is required for the synergistic induction of the proinflammatory genes. These findings indicate that BAFF-mediated reverse signaling can modulate LPS-induced inflammatory activation through regulation of NF-κB and CREB activity and point out the necessity to re-evaluate the role of BAFF in diseases where its expression is high in macrophages. PMID:28374824

  3. Ultrafine particles from diesel vehicle emissions at different driving cycles induce differential vascular pro-inflammatory responses: Implication of chemical components and NF-κB signaling

    PubMed Central

    2010-01-01

    Background Epidemiological evidence supports the association between exposure to ambient particulate matter (PM) and cardiovascular diseases. Chronic exposure to ultrafine particles (UFP; Dp <100 nm) is reported to promote atherosclerosis in ApoE knockout mice. Atherogenesis-prone factors induce endothelial dysfunction that contributes to the initiation and progression of atherosclerosis. We previously demonstrated that UFP induced oxidative stress via c-Jun N-terminal Kinases (JNK) activation in endothelial cells. In this study, we investigated pro-inflammatory responses of human aortic endothelial cells (HAEC) exposed to UFP emitted from a diesel truck under an idling mode (UFP1) and an urban dynamometer driving schedule (UFP2), respectively. We hypothesize that UFP1 and UFP2 with distinct chemical compositions induce differential pro-inflammatory responses in endothelial cells. Results UFP2 contained a higher level of redox active organic compounds and metals on a per PM mass basis than UFP1. While both UFP1 and UFP2 induced superoxide production and up-regulated stress response genes such as heme oxygenease-1 (HO-1), OKL38, and tissue factor (TF), only UFP2 induced the expression of pro-inflammatory genes such as IL-8 (2.8 ± 0.3-fold), MCP-1 (3.9 ± 0.4-fold), and VCAM (6.5 ± 1.1-fold) (n = 3, P < 0.05). UFP2-exposed HAEC also bound to a higher number of monocytes than UFP1-exposed HAEC (Control = 70 ± 7.5, UFP1 = 106.7 ± 12.5, UFP2 = 137.0 ± 8.0, n = 3, P < 0.05). Adenovirus NF-κB Luciferase reporter assays revealed that UFP2, but not UFP1, significantly induced NF-κB activities. NF-κB inhibitor, CAY10512, significantly abrogated UFP2-induced pro-inflammatory gene expression and monocyte binding. Conclusion While UFP1 induced higher level of oxidative stress and stress response gene expression, only UFP2, with higher levels of redox active organic compounds and metals, induced pro-inflammatory responses via NF-κB signaling. Thus, UFP with distinct

  4. Wnt/β-catenin signaling in T-cells drives epigenetic imprinting of pro-inflammatory properties and promotes colitis and colon cancer

    PubMed Central

    Keerthivasan, Shilpa; Aghajani, Katayoun; Dose, Marei; Molinero, Luciana; Khan, Mohammad W.; Venkatesvaran, Vysak; Weber, Christopher; Emmanuel, Akinola Olumide; Sun, Tianjao; Ramos, Elena M.; Keshavarzian, Ali; Mulcahy, Mary; Blatner, Nichole; Khazaie, Khashayarsha; Gounari, Fotini

    2014-01-01

    The density and type of lymphocytes that infiltrate colon tumors are predictive of the clinical outcome of colon cancer. High densities of TH17 cells and inflammation predict poor outcome, while infiltration by Tregs that naturally suppress inflammation is associated with longer patient survival. However, the role of Tregs in cancer remains controversial. We recently reported that Tregs in colon cancer patients can become pro-inflammatory and tumor promoting. These properties were directly linked with their expression of RORγt, the signature transcription factor of TH17 cells. Here, we report that Wnt/β-catenin signaling in T-cells promotes expression of RORγt. Expression of β-catenin was elevated in T-cells and Tregs of patients with colitis and colon cancer. Genetically engineered activation of β-catenin in mouse T-cells resulted in enhanced chromatin accessibility in the proximity of Tcf-1 binding sites genome-wide, induced expression of TH17 signature genes including RORγt, and promoted TH17-mediated inflammation. Strikingly, the mice had inflammation of intestine and colon and developed lesions indistinguishable from colitis-induced cancer. Activation of β-catenin only in Tregs was sufficient to produce inflammation and initiate cancer. Based on these findings we conclude that activation of Wnt/β-catenin signaling in T-cells and/or Tregs is causatively linked with the imprinting of pro-inflammatory properties and the promotion of colon cancer. PMID:24574339

  5. Cytosolic domain of the type I interleukin-1 receptor spontaneously recruits signaling molecules to activate a proinflammatory gene.

    PubMed Central

    Singh, R; Huang, S; Guth, T; Konieczkowski, M; Sedor, J R

    1997-01-01

    Immediate postreceptor events activated by IL-1-IL-1R interaction remain undefined. We have initiated studies to identify candidate signal transducers that associate with the cytosolic domain (cd) of the IL-1R. Immunocomplex kinase assays demonstrated an IL-1-activated myelin basic protein kinase activity that coprecipitated with the IL-1R from rat mesangial, mouse EL-4, and HeLa cells. Using glutathione-S-transferase (GST) fusion proteins, HeLa cell lysates next were assayed for kinases that associated with IL-1R cytoplasmic sequences. A GST-IL-1R fusion protein containing the entire cd (amino acids 369-569; GST-IL-1Rcd) recruited a kinase activity in the absence and presence of IL-1 stimulation. In contrast, a GST-IL-1R membrane-proximal region mutant (amino acids 369-501; GST-IL-1RcdDelta), which lacks COOH-terminal amino acid residues required for nuclear factor-kappaB activation, poorly phosphorylated MBP. In gel, kinase assays demonstrated 63-, 83-, and 100-kD kinases that specifically coprecipitated with the HeLa IL-1R and the GST-IL-1Rcd, but not GST-IL-1RcdDelta. 35S-labeled proteins, with Mrs identical to the kinase activities, stably associated with GST-IL-1Rcd. Transient transfection assays of 293 cells were used to evaluate the functional significance of these findings. Simply increasing IL-1cd expression in 293 cells stimulated 5'-IL-6 flanking region-regulated CAT activity threefold above control, an effect blocked by the kinase inhibitors staurosporine and calphostin C. In summary, we have identified two previously unrecognized 63- and 83-kD kinases as well as a protein with an Mr similar to the recently cloned IL-1R-associated kinase, all of which associate spontaneously with the IL-1Rcd. Ectopic IL-1Rcd expression was sufficient to trigger cellular activation, suggesting that the extracellular domain of the intact receptor represses signal transduction until IL-1 is bound. Given that the IL-1Rcd signaling domain has been conserved in a

  6. Flagellin acting via TLR5 is the major activator of key signaling pathways leading to NF-κB and proinflammatory gene program activation in intestinal epithelial cells

    PubMed Central

    Tallant, Thomas; Deb, Amitabha; Kar, Niladri; Lupica, Joseph; de Veer, Michael J; DiDonato, Joseph A

    2004-01-01

    Background Infection of intestinal epithelial cells by pathogenic Salmonella leads to activation of signaling cascades that ultimately initiate the proinflammatory gene program. The transcription factor NF-κB is a key regulator/activator of this gene program and is potently activated. We explored the mechanism by which Salmonella activates NF-κB during infection of cultured intestinal epithelial cells and found that flagellin produced by the bacteria and contained on them leads to NF-κB activation in all the cells; invasion of cells by the bacteria is not required to activate NF-κB. Results Purified flagellin activated the mitogen activated protein kinase (MAPK), stress-activated protein kinase (SAPK) and Ikappa B kinase (IKK) signaling pathways that lead to expression of the proinflammatory gene program in a temporal fashion nearly identical to that of infection of intestinal epithelial cells by Salmonella. Flagellin expression was required for Salmonella invasion of host cells and it activated NF-κB via toll-like receptor 5 (TLR5). Surprisingly, a number of cell lines found to be unresponsive to flagellin express TLR5 and expression of exogenous TLR5 in these cells induces NF-κB activity in response to flagellin challenge although not robustly. Conversely, overexpression of dominant-negative TLR5 alleles only partially blocks NF-κB activation by flagellin. These observations are consistent with the possibility of either a very stable TLR5 signaling complex, the existence of a low abundance flagellin co-receptor or required adapter, or both. Conclusion These collective results provide the evidence that flagellin acts as the main determinant of Salmonella mediated NF-κB and proinflammatory signaling and gene activation by this flagellated pathogen. In addition, expression of the fli C gene appears to play an important role in the proper functioning of the TTSS since mutants that fail to express fli C are defective in expressing a subset of Sip proteins and

  7. ISA-2011B, a Phosphatidylinositol 4-Phosphate 5-Kinase α Inhibitor, Impairs CD28-Dependent Costimulatory and Pro-inflammatory Signals in Human T Lymphocytes

    PubMed Central

    Kunkl, Martina; Porciello, Nicla; Mastrogiovanni, Marta; Capuano, Cristina; Lucantoni, Federica; Moretti, Chiara; Persson, Jenny L.; Galandrini, Ricciarda; Buzzetti, Raffaella; Tuosto, Loretta

    2017-01-01

    Phosphatidylinositol 4,5-biphosphate (PIP2) is a membrane phospholipid that controls the activity of several proteins regulating cytoskeleton reorganization, cytokine gene expression, T cell survival, proliferation, and differentiation. Phosphatidylinositol 4-phosphate 5-kinases (PIP5Ks) are the main enzymes involved in PIP2 biosynthesis by phosphorylating phosphatidylinositol 4-monophosphate (PI4P) at the D5 position of the inositol ring. In human T lymphocytes, we recently found that CD28 costimulatory molecule is pivotal for PIP2 turnover by recruiting and activating PIP5Kα. We also found that PIP5Kα is the main regulator of both CD28 costimulatory signals integrating those delivered by TCR as well as CD28 autonomous signals regulating the expression of pro-inflammatory genes. Given emerging studies linking alterations of PIP2 metabolism to immune-based diseases, PIP5Kα may represent a promising target to modulate immunity and inflammation. Herewith, we characterized a recently discovered inhibitor of PIP5Kα, ISA-2011B, for its inhibitory effects on T lymphocyte functions. We found that the inhibition of PIP5Kα lipid-kinase activity by ISA-2011B significantly impaired CD28 costimulatory signals necessary for TCR-mediated Ca2+ influx, NF-AT transcriptional activity, and IL-2 gene expression as well as CD28 autonomous signals regulating the activation of NF-κB and the transcription of pro-inflammatory cytokine and chemokine genes. Moreover, our data on the inhibitory effects of ISA-2011B on CD28-mediated upregulation of inflammatory cytokines related to Th17 cell phenotype in type 1 diabetes patients suggest ISA-2011B as a promising anti-inflammatory drug. PMID:28491063

  8. 17β-ESTRADIOL INCREASES LEISHMANIA MEXICANA KILLING IN MACROPHAGES FROM DBA/2 MICE BY ENHANCING PRODUCTION OF NITRIC OXIDE BUT NOT PRO-INFLAMMATORY CYTOKINES

    PubMed Central

    LEZAMA-DÁVILA, C.M.; ISAAC-MÁRQUEZ, A.P.; BARBI, J.; OGHUMU, S.; SATOSKAR, A.R.

    2014-01-01

    We have previously shown that female DBA/2 mice are significantly more resistant to Leishmania mexicana compared with males. Here, we have analyzed the effect of 17β-estradiol (E2) on function and cytokine production in male and female DBA/2 macrophages in vitro. We show that E2 increases NO production and parasite killing in L. mexicana-infected male and female DBA/2 macrophages without increasing production of pro-inflammatory cytokines. These data indicate that E2 may enhance leishmanicidal activity in macrophages by directly regulating production of NO. PMID:17556622

  9. Progressive Obesity Alters Ovarian Folliculogenesis with Impacts on Pro-Inflammatory and Steroidogenic Signaling in Female Mice1

    PubMed Central

    Nteeba, Jackson; Ganesan, Shanthi; Keating, Aileen F.

    2014-01-01

    ABSTRACT Diet-induced obesity induces immune cell infiltration and inflammation in peri-ovarian adipose tissue and mRNA expression of inflammatory markers in ovarian tissue. Whether these changes are associated with obesity-related ovarian dysfunction remains unknown. In the present study, qRT-PCR and Western blotting techniques were used to compare mRNA and protein abundance of ovarian immune cell and inflammation markers, along with NF-kappaB and steroidogenic pathway members in normal wild-type non-agouti (a/a; lean) and lethal yellow mice (KK.CG-Ay/J; obese) at 6, 12, 18, or 24 wk of age. Our data revealed that, beginning at 12 wk of age, NF-kappaB inflammatory signaling members were elevated (P < 0.05) in obese females. Interestingly obesity had opposing and temporal effects on the steroidogenic enzyme pathway. Obesity decreased (P < 0.05) STAR protein at 12, 18, and 24 wk of age. CYP11A1 and CYP19A1 proteins were increased (P < 0.05) at 12 wk but were decreased (P < 0.05) at 18 and 24 wk. Interestingly, CYP19A1 was increased in lethal yellow mouse ovaries at 6 wk of age, potentially indicating early puberty onset. These data demonstrate that obesity alters expression of ovarian inflammatory and steroidogenic pathway genes in ways which could adversely affect ovarian function. PMID:25143355

  10. Targeting aPKC disables oncogenic signaling by both the EGFR and the proinflammatory cytokine TNFα in glioblastoma

    PubMed Central

    Perry, Anthony S.; Rushing, Elisabeth J.; Mandell, Edward K.; Dietrich, Justin D.; Errasti, Andrea E.; Gibbs, Daniel; Berens, Michael E.; Loftus, Joseph C.; Hulme, Christopher; Yang, Weiwei; Lu, Zhimin; Aldape, Kenneth; Sanai, Nader; Rothlin, Carla V.; Ghosh, Sourav

    2015-01-01

    Grade IV glioblastoma is characterized by increased kinase activity of epidermal growth factor receptor (EGFR); however, EGFR kinase inhibitors have failed to improve survival in individuals with this cancer because resistance to these drugs often develops. We showed that tumor necrosis factor–α (TNFα) produced in the glioblastoma microenvironment activated atypical protein kinase C (aPKC), thereby producing resistance to EGFR kinase inhibitors. Additionally, we identified that aPKC was required both for paracrine TNFα-dependent activation of the transcription factor nuclear factor κB (NF-κB) and for tumor cell–intrinsic receptor tyrosine kinase signaling. Targeting aPKC decreased tumor growth in mouse models of glioblastoma, including models of EGFR kinase inhibitor–resistant glioblastoma. Furthermore, aPKC abundance and activity were increased in human glioblastoma tumor cells, and high aPKC abundance correlated with poor prognosis. Thus, targeting aPKC might provide an improved molecular approach for glioblastoma therapy. PMID:25118327

  11. Increased Blood Levels of Growth Factors, Proinflammatory Cytokines, and Th17 Cytokines in Patients with Newly Diagnosed Type 1 Diabetes.

    PubMed

    Alnek, Kristi; Kisand, Kalle; Heilman, Kaire; Peet, Aleksandr; Varik, Karin; Uibo, Raivo

    2015-01-01

    The production of several cytokines could be dysregulated in type 1 diabetes (T1D). In particular, the activation of T helper (Th) type 1 (Th1) cells has been proposed to underlie the autoimmune pathogenesis of the disease, although roles for inflammatory processes and the Th17 pathway have also been shown. Nevertheless, despite evidence for the role of cytokines before and at the onset of T1D, the corresponding findings are inconsistent across studies. Moreover, conflicting data exist regarding the blood cytokine levels in T1D patients. The current study was performed to investigate genetic and autoantibody markers in association with the peripheral blood cytokine profiles by xMap multiplex technology in newly diagnosed young T1D patients and age-matched healthy controls. The onset of young-age T1D was characterized by the upregulation of growth factors, including granulocyte macrophage-colony stimulating factor (GM-CSF) and interleukin (IL)-7, the proinflammatory cytokine IL-1β (but not IL-6 or tumor necrosis factor [TNF]-α), Th17 cytokines, and the regulatory cytokines IL-10 and IL-27. Ketoacidosis and autoantibodies (anti-IA-2 and -ZnT8), but not human leukocyte antigen (HLA) genotype, influenced the blood cytokine levels. These findings broaden the current understanding of the dysregulation of systemic levels of several key cytokines at the young-age onset of T1D and provide a further basis for the development of novel immunoregulatory treatments in this disease.

  12. Pro-inflammatory Signaling in a 3D Organotypic Skin Model after Low LET Irradiation-NF-κB, COX-2 Activation, and Impact on Cell Differentiation.

    PubMed

    Acheva, Anna; Schettino, Giuseppe; Prise, Kevin M

    2017-01-01

    Nearly 85% of radiotherapy patients develop acute radiation dermatitis, which is an inflammatory reaction of the skin at the treatment field and in the surrounding area. The aims of this study were to unravel the mechanisms of radiation-induced inflammatory responses after localized irradiation in a human 3D organotypic skin culture model. This could provide possible inflammatory targets for reduction of skin side effects. 3D organotypic skin cultures were set up and locally irradiated with 225 kVp X-rays, using a combination of full exposure and partial shielding (50%) of the cultures. The secretion of pro-inflammatory cytokines, the phenotype, and the differentiation markers expression of the cultures were assessed up to 10 days postirradiation. The pro-inflammatory transcription factor nuclear factor kappa B (NF-κB) and cyclooxygenase-2 (COX-2) pathways have been studied. The results showed fast activation of NF-κB, most likely triggered by DNA damage in the irradiated cells, followed by upregulation of p38 MAPK and COX-2 in the irradiated and surrounding, non-irradiated, areas of the 3D cultures. The application of the COX-2 inhibitor sc-236 was effective at reducing the COX-2 mRNA levels 4 h postirradiation. The same inhibitor also suppressed the PGE2 secretion significantly 72 h after the treatment. The expression of a pro-inflammatory phenotype and abnormal differentiation markers of the cultures were also reduced. However, the use of an NF-κB inhibitor (Bay 11-7085) did not have the predicted positive effect on the cultures phenotype postirradiation. Radiation-induced pro-inflammatory responses have been observed in the 3D skin model. The activated signaling pathways involved NF-κB transcription factor and its downstream target COX-2. Further experiments aiming to suppress the inflammatory response via specific inhibitors showed that COX-2 is a suitable target for reduction of the normal skin inflammatory responses at radiotherapy, while NF

  13. Pro-inflammatory Signaling in a 3D Organotypic Skin Model after Low LET Irradiation—NF-κB, COX-2 Activation, and Impact on Cell Differentiation

    PubMed Central

    Acheva, Anna; Schettino, Giuseppe; Prise, Kevin M.

    2017-01-01

    Nearly 85% of radiotherapy patients develop acute radiation dermatitis, which is an inflammatory reaction of the skin at the treatment field and in the surrounding area. The aims of this study were to unravel the mechanisms of radiation-induced inflammatory responses after localized irradiation in a human 3D organotypic skin culture model. This could provide possible inflammatory targets for reduction of skin side effects. 3D organotypic skin cultures were set up and locally irradiated with 225 kVp X-rays, using a combination of full exposure and partial shielding (50%) of the cultures. The secretion of pro-inflammatory cytokines, the phenotype, and the differentiation markers expression of the cultures were assessed up to 10 days postirradiation. The pro-inflammatory transcription factor nuclear factor kappa B (NF-κB) and cyclooxygenase-2 (COX-2) pathways have been studied. The results showed fast activation of NF-κB, most likely triggered by DNA damage in the irradiated cells, followed by upregulation of p38 MAPK and COX-2 in the irradiated and surrounding, non-irradiated, areas of the 3D cultures. The application of the COX-2 inhibitor sc-236 was effective at reducing the COX-2 mRNA levels 4 h postirradiation. The same inhibitor also suppressed the PGE2 secretion significantly 72 h after the treatment. The expression of a pro-inflammatory phenotype and abnormal differentiation markers of the cultures were also reduced. However, the use of an NF-κB inhibitor (Bay 11-7085) did not have the predicted positive effect on the cultures phenotype postirradiation. Radiation-induced pro-inflammatory responses have been observed in the 3D skin model. The activated signaling pathways involved NF-κB transcription factor and its downstream target COX-2. Further experiments aiming to suppress the inflammatory response via specific inhibitors showed that COX-2 is a suitable target for reduction of the normal skin inflammatory responses at radiotherapy, while NF

  14. Prenatal stress increases the expression of proinflammatory cytokines and exacerbates the inflammatory response to LPS in the hippocampal formation of adult male mice.

    PubMed

    Diz-Chaves, Yolanda; Astiz, Mariana; Bellini, Maria José; Garcia-Segura, Luis M

    2013-02-01

    Early life experiences, such as prenatal stress, may result in permanent alterations in the function of the nervous and immune systems. In this study we have assessed whether prenatal stress affects the inflammatory response of the hippocampal formation of male mice to an inflammatory challenge during adulthood. Pregnant C57BL/6 mice were randomly assigned to stress (n=10) or non-stress (n=10) groups. Animals of the stress group were placed in plastic transparent cylinders and exposed to bright light for 3 sessions of 45min every day from gestational day 12 to parturition. Non-stressed pregnant mice were left undisturbed. At four months of age, non stressed and prenatally stressed male offspring were killed, 24h after the systemic administration of lipopolysaccharide (LPS) or vehicle. Under basal conditions, prenatally stressed animals showed increased expression of interleukin 1β and tumor necrosis factor-α (TNF-α) in the hippocampus and an increased percentage of microglia cells with reactive morphology in CA1 compared to non-stressed males. Furthermore, prenatally stressed mice showed increased TNF-α immunoreactivity in CA1 and increased number of Iba-1 immunoreactive microglia and GFAP-immunoreactive astrocytes in the dentate gyrus after LPS administration. In contrast, LPS did not induce such changes in non-stressed animals. These findings indicate that prenatal stress induces a basal proinflammatory status in the hippocampal formation during adulthood that results in an enhanced activation of microglia and astrocytes in response to a proinflammatory insult.

  15. Dietary Fish Oil Inhibits Pro-Inflammatory and ER Stress Signalling Pathways in the Liver of Sows during Lactation

    PubMed Central

    Gessner, Denise K.; Gröne, Birthe; Couturier, Aline; Rosenbaum, Susann; Hillen, Sonja; Becker, Sabrina; Erhardt, Georg; Reiner, Gerald; Ringseis, Robert; Eder, Klaus

    2015-01-01

    Lactating sows have been shown to develop typical signs of an inflammatory condition in the liver during the transition from pregnancy to lactation. Hepatic inflammation is considered critical due to the induction of an acute phase response and the activation of stress signaling pathways like the endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR), both of which impair animal´s health and performance. Whether ER stress-induced UPR is also activated in the liver of lactating sows and whether dietary fish oil as a source of anti-inflammatory effects n-3 PUFA is able to attenuate hepatic inflammation and ER stress-induced UPR in the liver of sows is currently unknown. Based on this, two experiments with lactating sows were performed. The first experiment revealed that ER stress-induced UPR occurs also in the liver of sows during lactation. This was evident from the up-regulation of a set of genes regulated by the UPR and numerically increased phosphorylation of the ER stress-transducer PERK and PERK-mediated phosphorylation of eIF2α and IκB. The second experiment showed that fish oil inhibits ER stress-induced UPR in the liver of lactating sows. This was demonstrated by decreased mRNA levels of a number of UPR-regulated genes and reduced phosphorylation of PERK and PERK-mediated phosphorylation of eIF2α and IκB in the liver of the fish oil group. The mRNA levels of various nuclear factor-κB-regulated genes encoding inflammatory mediators and acute phase proteins in the liver of lactating sows were also reduced in the fish oil group. In line with this, the plasma levels of acute phase proteins were reduced in the fish oil group, although differences to the control group were not significant. In conclusion, ER stress-induced UPR is present in the liver of lactating sows and fish oil is able to inhibit inflammatory signaling pathways and ER stress-induced UPR in the liver. PMID:26351857

  16. Dietary Fish Oil Inhibits Pro-Inflammatory and ER Stress Signalling Pathways in the Liver of Sows during Lactation.

    PubMed

    Gessner, Denise K; Gröne, Birthe; Couturier, Aline; Rosenbaum, Susann; Hillen, Sonja; Becker, Sabrina; Erhardt, Georg; Reiner, Gerald; Ringseis, Robert; Eder, Klaus

    2015-01-01

    Lactating sows have been shown to develop typical signs of an inflammatory condition in the liver during the transition from pregnancy to lactation. Hepatic inflammation is considered critical due to the induction of an acute phase response and the activation of stress signaling pathways like the endoplasmic reticulum (ER) stress-induced unfolded protein response (UPR), both of which impair animal's health and performance. Whether ER stress-induced UPR is also activated in the liver of lactating sows and whether dietary fish oil as a source of anti-inflammatory effects n-3 PUFA is able to attenuate hepatic inflammation and ER stress-induced UPR in the liver of sows is currently unknown. Based on this, two experiments with lactating sows were performed. The first experiment revealed that ER stress-induced UPR occurs also in the liver of sows during lactation. This was evident from the up-regulation of a set of genes regulated by the UPR and numerically increased phosphorylation of the ER stress-transducer PERK and PERK-mediated phosphorylation of eIF2α and IκB. The second experiment showed that fish oil inhibits ER stress-induced UPR in the liver of lactating sows. This was demonstrated by decreased mRNA levels of a number of UPR-regulated genes and reduced phosphorylation of PERK and PERK-mediated phosphorylation of eIF2α and IκB in the liver of the fish oil group. The mRNA levels of various nuclear factor-κB-regulated genes encoding inflammatory mediators and acute phase proteins in the liver of lactating sows were also reduced in the fish oil group. In line with this, the plasma levels of acute phase proteins were reduced in the fish oil group, although differences to the control group were not significant. In conclusion, ER stress-induced UPR is present in the liver of lactating sows and fish oil is able to inhibit inflammatory signaling pathways and ER stress-induced UPR in the liver.

  17. The proinflammatory LTB4/BLT1 signal axis confers resistance to TGF-β1-induced growth inhibition by targeting Smad3 linker region

    PubMed Central

    Park, Seong Ji; Jo, Eun Ji; Lee, Young K.; Lim, Seunghwan; Kim, Jae-Hong; Letterio, John J.; Liu, Fang; Kim, Seong-Jin; Kim, Byung-Chul

    2015-01-01

    Leukotriene B4 (LTB4) is a potent pro-inflammatory eicosanoid that is derived from arachidonic acid, and its signaling is known to have a tumor-promoting role in several cancer types. In this study, we investigated whether enhanced LTB4 signaling confers resistance to the cytostatic transforming growth factor-β1 (TGF-β1) response. We found that LTB4 pretreatment or ectopic expression of BLT1, a high affinity LTB4 receptor, fully abrogated TGF-β1-induced cell cycle arrest and expression of p15INK4B and p27KIP1. Mechanism study revealed that LTB4-mediated suppression of TGF-β1-induced Smad3 activation and growth inhibition was due to enhanced phosphorylation of Smad3 linker region (pSmad3L) through activation of BLT1-NAD(P)H oxidase (NOX)-reactive oxygen species (ROS)-epidermal growth factor receptor (EGFR)-phosphatidylinositol 3-kinase (PI3-K)-extracellular signal-activated kinase1/2 (ERK1/2)-linked signaling cascade. Furthermore, the LTB4/BLT1 signaling pathway leading to pSmad3L was constitutively activated in breast cancer cells and was correlated with TGF-β1-resistant growth of the cells in vitro and in vivo. In human breast cancer tissues, the expression level of pSmad3L (Thr179) had a positive correlation with BLT1 expression. Collectively, our data demonstrate for the first time that the induction of pSmad3L through BLT1-NOX-ROS-EGFR-PI3K-ERK1/2 signaling pathway is a key mechanism by which LTB4 blocks the anti-proliferative responses of TGF-β1, providing a novel mechanistic insight into the connection between enhanced inflammatory signal and cancer cell growth. PMID:26497676

  18. The proinflammatory LTB4/BLT1 signal axis confers resistance to TGF-β1-induced growth inhibition by targeting Smad3 linker region.

    PubMed

    Jeon, Woo-Kwang; Choi, Jiyeon; Park, Seong Ji; Jo, Eun Ji; Lee, Young K; Lim, Seunghwan; Kim, Jae-Hong; Letterio, John J; Liu, Fang; Kim, Seong-Jin; Kim, Byung-Chul

    2015-12-08

    Leukotriene B4 (LTB4) is a potent pro-inflammatory eicosanoid that is derived from arachidonic acid, and its signaling is known to have a tumor-promoting role in several cancer types. In this study, we investigated whether enhanced LTB4 signaling confers resistance to the cytostatic transforming growth factor-β1 (TGF-β1) response. We found that LTB4 pretreatment or ectopic expression of BLT1, a high affinity LTB4 receptor, fully abrogated TGF-β1-induced cell cycle arrest and expression of p15INK4B and p27KIP1. Mechanism study revealed that LTB4-mediated suppression of TGF-β1-induced Smad3 activation and growth inhibition was due to enhanced phosphorylation of Smad3 linker region (pSmad3L) through activation of BLT1-NAD(P)H oxidase (NOX)-reactive oxygen species (ROS)-epidermal growth factor receptor (EGFR)-phosphatidylinositol 3-kinase (PI3-K)-extracellular signal-activated kinase1/2 (ERK1/2)-linked signaling cascade. Furthermore, the LTB4/BLT1 signaling pathway leading to pSmad3L was constitutively activated in breast cancer cells and was correlated with TGF-β1-resistant growth of the cells in vitro and in vivo. In human breast cancer tissues, the expression level of pSmad3L (Thr179) had a positive correlation with BLT1 expression. Collectively, our data demonstrate for the first time that the induction of pSmad3L through BLT1-NOX-ROS-EGFR-PI3K-ERK1/2 signaling pathway is a key mechanism by which LTB4 blocks the anti-proliferative responses of TGF-β1, providing a novel mechanistic insight into the connection between enhanced inflammatory signal and cancer cell growth.

  19. Retinol-Binding Protein 4 Inhibits Insulin Signaling in Adipocytes by Inducing Proinflammatory Cytokines in Macrophages through a c-Jun N-Terminal Kinase- and Toll-Like Receptor 4-Dependent and Retinol-Independent Mechanism

    PubMed Central

    Norseen, Julie; Hosooka, Tetsuya; Hammarstedt, Ann; Yore, Mark M.; Kant, Shashi; Aryal, Pratik; Kiernan, Urban A.; Phillips, David A.; Maruyama, Hiroshi; Kraus, Bettina J.; Usheva, Anny; Davis, Roger J.; Smith, Ulf

    2012-01-01

    Retinol-binding protein 4 (RBP4), the sole retinol transporter in blood, is secreted from adipocytes and liver. Serum RBP4 levels correlate highly with insulin resistance, other metabolic syndrome factors, and cardiovascular disease. Elevated serum RBP4 causes insulin resistance, but the molecular mechanisms are unknown. Here we show that RBP4 induces expression of proinflammatory cytokines in mouse and human macrophages and thereby indirectly inhibits insulin signaling in cocultured adipocytes. This occurs through activation of c-Jun N-terminal protein kinase (JNK) and Toll-like receptor 4 (TLR4) pathways independent of the RBP4 receptor, STRA6. RBP4 effects are markedly attenuated in JNK1−/− JNK2−/− macrophages and TLR4−/− macrophages. Because RBP4 is a retinol-binding protein, we investigated whether these effects are retinol dependent. Unexpectedly, retinol-free RBP4 (apo-RBP4) is as potent as retinol-bound RBP4 (holo-RBP4) in inducing proinflammatory cytokines in macrophages. Apo-RBP4 is likely to be physiologically significant since RBP4/retinol ratios are increased in serum of lean and obese insulin-resistant humans compared to ratios in insulin-sensitive humans, indicating that higher apo-RBP4 is associated with insulin resistance independent of obesity. Thus, RBP4 may cause insulin resistance by contributing to the development of an inflammatory state in adipose tissue through activation of proinflammatory cytokines in macrophages. This process reveals a novel JNK- and TLR4-dependent and retinol- and STRA6-independent mechanism of action for RBP4. PMID:22431523

  20. The Clinical Significance of Increased Serum Proinflammatory Cytokines, C-Reactive Protein, and Erythrocyte Sedimentation Rate in Patients with Hidradenitis Suppurativa.

    PubMed

    Jiménez-Gallo, D; de la Varga-Martínez, R; Ossorio-García, L; Albarrán-Planelles, C; Rodríguez, C; Linares-Barrios, M

    2017-01-01

    To assess inflammatory serum markers including serum proinflammatory cytokines, C-reactive protein (CRP), and erythrocyte sedimentation rate (ESR) according to the clinical inflammatory activity of patients with hidradenitis suppurativa (HS). Seventy-four patients with HS were studied based on the Hidradenitis Suppurativa-Physician Global Assessment (HS-PGA) score and Hurley staging system. Proinflammatory cytokines were measured using a multiplex cytokine assay. Twenty-two healthy volunteers were recruited. Serum interleukin- (IL-) 6, IL-23, soluble tumour necrosis factor alpha (TNF-α) receptor I (sTNF-RI), CRP, and ESR were different in the patients with HS compared with those in the healthy controls (P < 0.05). The levels of IL-1β, IL-6, IL-8, IL-10, IL-12p70, IL-17A, sTNF-RII, CRP, and ESR were significantly elevated according to inflammatory activity based on HS-PGA scores (r > 0.25, P < 0.05). The levels of IL-6 (r = 0.53, P < 0.001), CRP (r = 0.54, P < 0.001), and ESR (r = 0.60, P < 0.001) were especially well correlated with clinical inflammatory activity based on HS-PGA scores. The levels of IL-6, IL-8, sTNF-RI, sTNF-RII, CRP, and ESR were significantly elevated according to Hurley staging system. Serum proinflammatory cytokines, CRP, and ESR are increased in relation to the clinical inflammatory activity of patients with HS compared with healthy controls. Serum IL-6, CRP, and ESR are effective biomarkers for evaluating the severity of HS.

  1. Ganglioside GD1a suppresses LPS-induced pro-inflammatory cytokines in RAW264.7 macrophages by reducing MAPKs and NF-κB signaling pathways through TLR4.

    PubMed

    Wang, Yiren; Cui, Yuting; Cao, Fayang; Qin, Yiyang; Li, Wenjing; Zhang, Jinghai

    2015-09-01

    Gangliosides, sialic acid-containing glycosphingolipids, have been considered to be involved in the development, differentiation, and function of nervous systems in vertebrates. However, the mechanisms for anti-inflammation caused by gangliosides are not clear. In this paper, we investigated the anti-inflammation effects of ganglioside GD1a by using RAW264.7 macrophages. Our data demonstrated that treatment of macrophages with lipopolysaccharide significantly increased the production of NO and pro-inflammatory cytokines. GD1a suppressed the induction of iNOS and COX-2 mRNA and protein expression and secretory pro-inflammatory cytokines in culture medium, such as TNFα, IL-1α and IL-1β. In addition, LPS-induced phosphorylation of mitogen-activating protein kinases and IκBα degradation followed by translocation of the NF-κB from the cytoplasm to the nucleus were attenuated after GD1a treatment. Furthermore, GD1a probably inhibited LPS binding to macrophages and LPS-induced accumulation between TLR4 and MyD88. Taken together, the results demonstrated that ganglioside GD1a inhibited LPS-induced inflammation in RAW 264.7 macrophages by suppressing phosphorylation of mitogen-activating protein kinases and activation of NF-κB through repressing the Toll-like receptor 4 signaling pathway. Copyright © 2015 Elsevier B.V. All rights reserved.

  2. Majoon ushba, a polyherbal compound, suppresses pro-inflammatory mediators and RANKL expression via modulating NFкB and MAPKs signaling pathways in fibroblast-like synoviocytes from adjuvant-induced arthritic rats.

    PubMed

    Ganesan, Ramamoorthi; Doss, Hari Madhuri; Rasool, Mahaboobkhan

    2016-08-01

    Fibroblast-like synoviocytes (FLS) are inhabitant mesenchymal cells of synovial joints and have been recognized to play an imperative role in the immunopathogenesis of rheumatoid arthritis (RA). Blocking these pathological roles of FLS provides a potentially important therapeutic strategy for the treatment for RA. A recent study had confirmed that majoon ushba (MU), a polyherbal unani compound, possesses anti-arthritic effects in in vivo. Toward this direction, an effort has been made to understand the effect of MU on FLS derived from adjuvant-induced arthritis (AIA) rats. Here, we observed that MU administration (100-300 µg/ml) significantly inhibited the expression and phosphorylation of NFкB-p65 protein similar to that of the Bay 11-7082 (NFкB inhibitor) in NFкB signaling pathway and suppressed the protein expression of ERK1/2 and JNK1/2 in MAPKs signaling pathway in AIA-FLS. In addition, the protein expression of TNF-α, IL-17, RANKL, and iNOS was also found reduced. MU treatment significantly inhibited the mRNA expression of pro-inflammatory mediators (TNF-α, IL-1β, IL-6, MCP-1, IL-17, iNOS, and COX-2), transcription factors (NFкB-p65 and AP-1), and RANKL and attenuated the overproduction of TNF-α, IL-1β, IL-6, and MCP-1 (ELISA) in AIA-FLS. Furthermore, MU treatment significantly inhibited the level of lipid peroxidation, lysosomal enzymes release, and glycoproteins and increased antioxidant status (superoxide dismutase and catalase) in AIA-FLS. In conclusion, the results of this study provide evidence that MU possesses anti-inflammatory effect against AIA-FLS through the decrease in pro-inflammatory mediators expression by suppressing NFкB and MAPKs signaling pathways.

  3. Hydrogen gas attenuates sevoflurane neurotoxicity through inhibiting nuclear factor κ-light-chain-enhancer of activated B cells signaling and proinflammatory cytokine release in neonatal rats.

    PubMed

    Shi, Yiwei; Wang, Gang; Li, Jinyuan; Yu, Wenli

    2017-09-18

    Anesthesia neurotoxicity in developing brain has gained increasing attention. However, knowledge regarding its mitigating strategies remains scant. Sevoflurane, a commonly used anesthetic, is responsible for learning and memory deficits in neonates. Molecular hydrogen is reported to be a potential neuroprotective agent because of its antioxidative and anti-inflammatory activities. This study aimed to investigate the effect of hydrogen gas on sevoflurane neurotoxicity. The newborn rats were treated with sevoflurane and/or hydrogen gas for 2 h. Spatial recognition memory and fear memory were determined by Y-maze and fear conditioning tests at 10 weeks of age. Nuclear factor κ-light-chain-enhancer of activated B cells (NF-κB) and proinflammatory cytokine levels were detected using western blot analysis. The data showed that the spatial recognition memory and fear memory of the rats treated with sevoflurane decreased compared with the control, and the cognitive function of the rats treated with sevoflurane and hydrogen gas significantly increased in comparison with treatment with sevoflurane alone. Moreover, hydrogen gas suppressed NF-κB phosphorylation and nuclear translocation and reduced the production of interleukin-1β, interleukin-6, and tumor necrosis factor-α following sevoflurane administration. Thus, the results proposed that hydrogen gas might protect against sevoflurane neurotoxicity by inhibiting NF-κB activation and proinflammatory cytokine release, providing a novel therapeutic strategy for anesthesia neurotoxicity.

  4. Healthy working school teachers with high effort-reward-imbalance and overcommitment show increased pro-inflammatory immune activity and a dampened innate immune defence.

    PubMed

    Bellingrath, Silja; Rohleder, Nicolas; Kudielka, Brigitte M

    2010-11-01

    To test whether chronic work stress is accompanied by altered immune functioning, changes in lymphocyte subsets and in lymphocyte production of cytokines were examined in reaction to acute psychosocial stress. Work stress was measured according to Siegrist's effort-reward-imbalance (ERI) model. ERI reflects stress due to a lack of reciprocity between costs and gains at work. Overcommitment (OC) is conceptualized as a dysfunctional coping pattern mainly characterized by the inability to withdraw from work obligations. Fifty-five healthy teachers (34 women, 21 men, mean age 50.0 ± 8.47 years) were exposed to a standardized laboratory stressor (Trier Social Stress Test). Lymphocyte subset counts and lymphocyte production of tumor-necrosis-factor (TNF)-α, interferon (IFN)-γ, interleukin (IL)-2, -4, -6 and -10 were measured before and after challenge. High levels of ERI and OC were associated with lower natural killer (NK) cell (CD16+/56+) numbers whereas high levels of OC were related to a lower increase in T-helper cells (CD4+) after stress. Furthermore, subjects with higher ERI showed an overall increased pro-inflammatory activity, with higher TNF-α production at both time points and elevated pre-stress IL-6 production. IL-10 production decreased with higher ERI after stress. The ratios of TNF-α/IL-10 and IL-6/IL-10 were significantly increased in subjects high on ERI. Finally, OC was associated with higher IL-2 production post-stress. The present findings suggest a dampened innate immune defence, reflected in lower NK cell numbers together with an increased pro-inflammatory activity in teachers high on ERI and OC. Such pathways could partly be responsible for the increased vulnerability for stress-related diseases in individuals suffering from chronic work stress.

  5. Potential of flavonoids as anti-inflammatory agents: modulation of pro-inflammatory gene expression and signal transduction pathways.

    PubMed

    Tuñón, M J; García-Mediavilla, M V; Sánchez-Campos, S; González-Gallego, J

    2009-03-01

    Flavonoids are a large class of naturally occurring compounds widely present in fruits, vegetables, and beverages derived from plants. Reports have suggested that these compounds might be useful for the prevention of a number of diseases, partly due to their anti-inflammatory properties. It has been demonstrated that flavonoids are able to inhibit expression of isoforms of inducible nitric oxide synthase, ciclooxygenase and lipooxygenase, which are responsible for the production of a great amount of nitric oxide, prostanoids and leukotrienes, as well as other mediators of the inflammatory process such as cytokines, chemokines or adhesion molecules. Modulation of the cascade of molecular events leading to the over-expression of those mediators include inhibition of transcription factors such as nuclear factor kappa B, activator protein 1, signal transducers and activators of transcription, CCAAT/enhancer binding protein and others. Effects on the binding capacity of transcription factors may be regulated through the inhibition of protein kinases involved in signal transduction, such as mitogen activated protein kinases. Although the numerous studies published with in vitro approaches allow identifying molecular mechanisms of flavonoid effects, the limited bioavailability of these molecules makes necessary validation in humans. Whatever the case, the data available make clear the potential utility of dietary flavonoids or new flavonoid-based agents for the possible treatment of inflammatory diseases. The present review summarizes recent research data focusing on the modulation of the expression of different inflammatory mediators by flavonoids and the effects on cell signaling pathways responsible for their anti-inflammatory activity.

  6. Gd compounds signaling through Toll-like receptors 4 and 7 in normal human macrophages: establishment of a proinflammatory phenotype and implications for the pathogenesis of Nephrogenic Systemic Fibrosis

    PubMed Central

    Wermuth, Peter J.; Jimenez, Sergio A.

    2012-01-01

    Nephrogenic Systemic Fibrosis (NSF) is a progressive disorder occurring in some renal insufficiency patients exposed to Gd based contrast agents (GdBCA). Previous studies demonstrated that the GdBCA Omniscan® upregulated several innate immunity pathways in normal differentiated human macrophages, induced rapid nuclear localization of the transcription factor NFκB, and increased the expression and production of numerous profibrotic/proinflammatory cytokines, chemokines and growth factors. To further examine GdBCA stimulation of the innate immune system, cultured human embryonic kidney 293 (HEK293) cells expressing one of seven different human TLRs or one of two human Nucleotide Oligomerization Domain (NOD)-like receptors (NLRs) were exposed in vitro for 24 h to various GdBCA. The signaling activity of each compound was evaluated by its ability to activate an NFκB-inducible reporter gene. Omniscan® and gadodiamide induced strong TLR 4 and 7 mediated reporter gene activation. The other Gd compounds examined failed to induce reporter gene activation. TLR pathway inhibition using chloroquine or an inhibitor of IL-1 receptor associated kinase 1 (IRAK1) and IRAK4 in normal differentiated human macrophages abrogated Omniscan®-induced gene expression. Omniscan® and gadodiamide signaling via TLR 4 and 7 resulted in increased production and expression of numerous proinflammatory/profibrotic cytokines, chemokines, and growth factors including CXCL10, CCL2, CCL8, CXCL12, IL-4, IL-6, TGF-β and VEGF. These observations suggest that TLR activation by environmental stimuli may participate in the pathogenesis of NSF and of other fibrotic disorders including systemic sclerosis. PMID:22649203

  7. Maternal Supplementation with Oligofructose (10%) during Pregnancy and Lactation Leads to Increased Pro-Inflammatory Status of the 21-D-Old Offspring

    PubMed Central

    Mennitti, Laís Vales; Oyama, Lila Missae; de Oliveira, Juliana Lopez; Hachul, Ana Claudia Losinskas; Santamarina, Aline Boveto; de Santana, Aline Alves; Okuda, Marcos Hiromu; Ribeiro, Eliane Beraldi; Oller do Nascimento, Claudia Maria da Penha; Pisani, Luciana Pellegrini

    2015-01-01

    Previously, we showed that oligofructose (10%) supplementation during pregnancy and lactation increased endotoxemia in 21-d-old pups. The present study evaluated the effect of 10% oligofructose diet supplementation during pregnancy and lactation in the presence or absence of hydrogenated vegetable fat on the pro-inflammatory status of 21-d-old offspring. On the first day of pregnancy, female Wistar rats were divided into the following groups: control diet (C), control diet supplemented with 10% oligofructose (CF), diet enriched with hydrogenated vegetable fat (T) or diet enriched with hydrogenated vegetable fat supplemented with 10% oligofructose (TF). Diets were maintained during pregnancy and lactation. Serum TNF-α (tumor necrosis factor alpha) was assessed using a specific kit. Protein expression was determined by Western Blotting, and the relative mRNA levels were analyzed by RT-PCR (real-time polymerase chain reaction). We observed that 10% oligofructose supplementation during pregnancy and lactation increased offspring’s IL-6R (interleukin-6 receptor) mRNA levels in the liver and RET (retroperitoneal white adipose tissue) and decreased ADIPOR2 (adiponectin receptor 2) and ADIPOR1 (adiponectin receptor 1) gene expression in liver and EDL (extensor digital longus)/ SOL (soleus) muscles of CF group. Additionally, TF group presented with increased serum TNF-α, protein expression of p-NFκBp65 (phosphorylated form of nuclear factor kappa B p65 subunit) in liver and IL-6R mRNA levels in RET. These findings were accompanied by decreased levels of ADIPOR1 mRNA in the EDL and SOL muscles of the TF group. In conclusion, supplementing the dam’s diet with 10% of oligofructose during pregnancy and lactation, independent of hydrogenated vegetable fat addition, contributes to the increased pro-inflammatory status of 21-d-old offspring, possibly through the activation of the TLR4 (toll like receptor 4) pathway. PMID:26147005

  8. Maternal Supplementation with Oligofructose (10%) during Pregnancy and Lactation Leads to Increased Pro-Inflammatory Status of the 21-D-Old Offspring.

    PubMed

    Mennitti, Laís Vales; Oyama, Lila Missae; de Oliveira, Juliana Lopez; Hachul, Ana Claudia Losinskas; Santamarina, Aline Boveto; de Santana, Aline Alves; Okuda, Marcos Hiromu; Ribeiro, Eliane Beraldi; Oller do Nascimento, Claudia Maria da Penha; Pisani, Luciana Pellegrini

    2015-01-01

    Previously, we showed that oligofructose (10%) supplementation during pregnancy and lactation increased endotoxemia in 21-d-old pups. The present study evaluated the effect of 10% oligofructose diet supplementation during pregnancy and lactation in the presence or absence of hydrogenated vegetable fat on the pro-inflammatory status of 21-d-old offspring. On the first day of pregnancy, female Wistar rats were divided into the following groups: control diet (C), control diet supplemented with 10% oligofructose (CF), diet enriched with hydrogenated vegetable fat (T) or diet enriched with hydrogenated vegetable fat supplemented with 10% oligofructose (TF). Diets were maintained during pregnancy and lactation. Serum TNF-α (tumor necrosis factor alpha) was assessed using a specific kit. Protein expression was determined by Western Blotting, and the relative mRNA levels were analyzed by RT-PCR (real-time polymerase chain reaction). We observed that 10% oligofructose supplementation during pregnancy and lactation increased offspring's IL-6R (interleukin-6 receptor) mRNA levels in the liver and RET (retroperitoneal white adipose tissue) and decreased ADIPOR2 (adiponectin receptor 2) and ADIPOR1 (adiponectin receptor 1) gene expression in liver and EDL (extensor digital longus)/ SOL (soleus) muscles of CF group. Additionally, TF group presented with increased serum TNF-α, protein expression of p-NFκBp65 (phosphorylated form of nuclear factor kappa B p65 subunit) in liver and IL-6R mRNA levels in RET. These findings were accompanied by decreased levels of ADIPOR1 mRNA in the EDL and SOL muscles of the TF group. In conclusion, supplementing the dam's diet with 10% of oligofructose during pregnancy and lactation, independent of hydrogenated vegetable fat addition, contributes to the increased pro-inflammatory status of 21-d-old offspring, possibly through the activation of the TLR4 (toll like receptor 4) pathway.

  9. Benzo(a)pyrene induces oxidative stress, pro-inflammatory cytokines, expression of nuclear factor-kappa B and deregulation of wnt/beta-catenin signaling in colons of BALB/c mice.

    PubMed

    Ajayi, Babajide O; Adedara, Isaac A; Farombi, Ebenezer O

    2016-09-01

    The incidence of colonic toxicity has been epidemiologically linked to the consumption of foods contaminated with benzo(a)pyrene (B[a]P). The present study investigated the effects of B[a]P on biomarkers of oxidative stress, inflammation and wnt-signaling in colon of BALB/c mice following exposure to 62.5, 125 and 250 mg/kg of B[a]P for 7 days by oral gavage. Exposure to B[a]P significantly decreased the colonic antioxidant enzymes activities and glutathione level with concomitant significant increase in myeloperoxidase activity, nitric oxide and lipid peroxidation levels. Colon histopathology results showed treatment-related lesions characterized by atrophy, mucosal ulceration and gland erosion in the B[a]P-treated mice. Immunohistochemistry analysis showed that B[a]P treatment increased the protein expression of nuclear factor kappa B, pro-inflammatory cytokines namely tumor necrosis factor alpha and interleukin-1β, as well as cyclooxygenase-2 and inducible nitric oxide synthase in the mice colon. Altered canonical wnt-signaling was confirmed by strong diaminobenzidine staining for p38 mitogen activated protein kinase, β-catenin expression and absence of adenomatous polyposis coli following B[a]P administration. The present data highlight that exposure to B[a]P induces colon injury via induction of oxidative and nitrosative stress, inflammatory biomarkers and dsyregulation wnt/β-catenin signaling, thus confirming the role of B[a]P in the pathogenesis of colonic toxicity.

  10. LY2109761 attenuates radiation-induced pulmonary murine fibrosis via reversal of TGF-β and BMP-associated proinflammatory and proangiogenic signals.

    PubMed

    Flechsig, Paul; Dadrich, Monika; Bickelhaupt, Sebastian; Jenne, Jürgen; Hauser, Kai; Timke, Carmen; Peschke, Peter; Hahn, Eric W; Gröne, Hermann-Josef; Yingling, Jonathan; Lahn, Michael; Wirkner, Ute; Huber, Peter E

    2012-07-01

    Radiotherapy is used for the treatment of lung cancer, but at the same time induces acute pneumonitis and subsequent pulmonary fibrosis, where TGF-β signaling is considered to play an important role. We irradiated thoraces of C57BL/6 mice (single dose, 20 Gy) and administered them a novel small-molecule TGF-β receptor I serine/threonine kinase inhibitor (LY2109761) orally for 4 weeks before, during, or after radiation. Noninvasive lung imaging including volume computed tomography (VCT) and MRI was conducted 6, 16, and 20 weeks after irradiation and was correlated to histologic findings. Expression profiling analysis and protein analysis was conducted in human primary fibroblasts. Radiation alone induced acute pulmonary inflammation and lung fibrosis after 16 weeks associated with reduced life span. VCT, MRI, and histology showed that LY2109761 markedly reduced inflammation and pulmonary fibrosis resulting in prolonged survival. Mechanistically, we found that LY2109761 reduced p-SMAD2 and p-SMAD1 expression, and transcriptomics revealed that LY2109761 suppressed expression of genes involved in canonical and noncanonical TGF-β signaling and downstream signaling of bone morphogenetic proteins (BMP). LY2109761 also suppressed radiation-induced inflammatory [e.g., interleukin (IL)-6, IL-7R, IL-8] and proangiogenic genes (e.g., ID1) indicating that LY2109761 achieves its antifibrotic effect by suppressing radiation-induced proinflammatory, proangiogenic, and profibrotic signals. Small-molecule inhibitors of the TGF-β receptor I kinase may offer a promising approach to treat or attenuate radiation-induced lung toxicity or other diseases associated with fibrosis. ©2012 AACR.

  11. IL-6 signaling blockade increases inflammation but does not affect muscle function in the mdx mouse

    PubMed Central

    2012-01-01

    Background IL-6 is a pleiotropic cytokine that modulates inflammatory responses and plays critical roles in muscle maintenance and remodeling. In the mouse model (mdx) of Duchenne Muscular Dystrophy, IL-6 and muscle inflammation are elevated, which is believed to contribute to the chronic inflammation and failure of muscle regeneration in DMD. The purpose of the current study was to examine the effect of blocking IL-6 signaling on the muscle phenotype including muscle weakness and pathology in the mdx mouse. Methods A monoclonal antibody against the IL-6 receptor (IL-6r mAb) that blocks local and systemic IL-6 signaling was administered to mdx and BL-10 mice for 5 weeks and muscle function, histology, and inflammation were examined. Results IL-6r mAb treatment increased mdx muscle inflammation including total inflammation score and ICAM-1 positive lumens in muscles. There was no significant improvement in muscle strength nor muscle pathology due to IL-6r mAb treatment in mdx mice. Conclusions These results showed that instead of reducing inflammation, IL-6 signaling blockade for 5 weeks caused an increase in muscle inflammation, with no significant change in indices related to muscle regeneration and muscle function. The results suggest a potential anti-inflammatory instead of the original hypothesized pro-inflammatory role of IL-6 signaling in the mdx mice. PMID:22716658

  12. A CD47-associated super-enhancer links pro-inflammatory signalling to CD47 upregulation in breast cancer.

    PubMed

    Betancur, Paola A; Abraham, Brian J; Yiu, Ying Y; Willingham, Stephen B; Khameneh, Farnaz; Zarnegar, Mark; Kuo, Angera H; McKenna, Kelly; Kojima, Yoko; Leeper, Nicholas J; Ho, Po; Gip, Phung; Swigut, Tomek; Sherwood, Richard I; Clarke, Michael F; Somlo, George; Young, Richard A; Weissman, Irving L

    2017-04-05

    CD47 is a cell surface molecule that inhibits phagocytosis of cells that express it by binding to its receptor, SIRPα, on macrophages and other immune cells. CD47 is expressed at different levels by neoplastic and normal cells. Here, to reveal mechanisms by which different neoplastic cells generate this dominant 'don't eat me' signal, we analyse the CD47 regulatory genomic landscape. We identify two distinct super-enhancers (SEs) associated with CD47 in certain cancer cell types. We show that a set of active constituent enhancers, located within the two CD47 SEs, regulate CD47 expression in different cancer cell types and that disruption of CD47 SEs reduces CD47 gene expression. Finally we report that the TNF-NFKB1 signalling pathway directly regulates CD47 by interacting with a constituent enhancer located within a CD47-associated SE specific to breast cancer. These results suggest that cancers can evolve SE to drive CD47 overexpression to escape immune surveillance.

  13. Obesity increases the production of proinflammatory mediators from adipose tissue T cells and compromises TCR repertoire diversity: implications for systemic inflammation and insulin resistance.

    PubMed

    Yang, Hyunwon; Youm, Yun-Hee; Vandanmagsar, Bolormaa; Ravussin, Anthony; Gimble, Jeffrey M; Greenway, Frank; Stephens, Jacqueline M; Mynatt, Randall L; Dixit, Vishwa Deep

    2010-08-01

    Emerging evidence suggests that increases in activated T cell populations in adipose tissue may contribute toward obesity-associated metabolic syndrome. The present study investigates three unanswered questions: 1) Do adipose-resident T cells (ARTs) from lean and obese mice have altered cytokine production in response to TCR ligation?; 2) Do the extralymphoid ARTs possess a unique TCR repertoire compared with lymphoid-resident T cells and whether obesity alters the TCR diversity in specific adipose depots?; and 3) Does short-term elimination of T cells in epididymal fat pad without disturbing the systemic T cell homeostasis regulate inflammation and insulin-action during obesity? We found that obesity reduced the frequency of naive ART cells in s.c. fat and increased the effector-memory populations in visceral fat. The ARTs from diet-induced obese (DIO) mice had a higher frequency of IFN-gamma(+), granzyme B(+) cells, and upon TCR ligation, the ARTs from DIO mice produced increased levels of proinflammatory mediators. Importantly, compared with splenic T cells, ARTs exhibited markedly restricted TCR diversity, which was further compromised by obesity. Acute depletion of T cells from epididymal fat pads improved insulin action in young DIO mice but did not reverse obesity-associated feed forward cascade of chronic systemic inflammation and insulin resistance in middle-aged DIO mice. Collectively, these data establish that ARTs have a restricted TCR-Vbeta repertoire, and T cells contribute toward the complex proinflammatory microenvironment of adipose tissue in obesity. Development of future long-term T cell depletion protocols specific to visceral fat may represent an additional strategy to manage obesity-associated comorbidities.

  14. Obesity Increases the Production of Proinflammatory Mediators from Adipose Tissue T Cells and Compromises TCR Repertoire Diversity: Implications for Systemic Inflammation and Insulin Resistance

    PubMed Central

    Yang, Hyunwon; Youm, Yun-Hee; Vandanmagsar, Bolormaa; Ravussin, Anthony; Gimble, Jeffrey M.; Greenway, Frank; Stephens, Jacqueline M.; Mynatt, Randall L.; Dixit, Vishwa Deep

    2016-01-01

    Emerging evidence suggests that increases in activated T cell populations in adipose tissue may contribute toward obesity-associated metabolic syndrome. The present study investigates three unanswered questions: 1) Do adipose-resident T cells (ARTs) from lean and obese mice have altered cytokine production in response to TCR ligation?; 2) Do the extralymphoid ARTs possess a unique TCR repertoire compared with lymphoid-resident T cells and whether obesity alters the TCR diversity in specific adipose depots?; and 3) Does short-term elimination of T cells in epididymal fat pad without disturbing the systemic T cell homeostasis regulate inflammation and insulin-action during obesity? We found that obesity reduced the frequency of naive ART cells in s.c. fat and increased the effector-memory populations in visceral fat. The ARTs from diet-induced obese (DIO) mice had a higher frequency of IFN-γ+, granzyme B+ cells, and upon TCR ligation, the ARTs from DIO mice produced increased levels of proinflammatory mediators. Importantly, compared with splenic T cells, ARTs exhibited markedly restricted TCR diversity, which was further compromised by obesity. Acute depletion of T cells from epididymal fat pads improved insulin action in young DIO mice but did not reverse obesity-associated feed forward cascade of chronic systemic inflammation and insulin resistance in middle-aged DIO mice. Collectively, these data establish that ARTs have a restricted TCR-Vβ repertoire, and T cells contribute toward the complex proinflammatory microenvironment of adipose tissue in obesity. Development of future long-term T cell depletion protocols specific to visceral fat may represent an additional strategy to manage obesity-associated comorbidities. PMID:20581149

  15. Feeding a high-concentrate corn straw diet increased the release of endotoxin in the rumen and pro-inflammatory cytokines in the mammary gland of dairy cows

    PubMed Central

    2014-01-01

    Background The objective of this study was to investigate the effects of feeding a high-concentrate corn straw diet on the release of endotoxin in the rumen and the changes of pro-inflammatory cytokines in the mammary gland of dairy cows in comparison with a low-concentrate corn straw diet and a low-concentrate mixed forage diet. Thirty second-parity Chinese Holstein cows in mid-lactation with a body condition score of 2.86 ± 0.29, weighing 543 ± 57 kg and producing 24.32 ± 3.86 kg milk per day were randomly assigned to 1 of the 3 diets (n = 10 per treatment): 1) low-concentrate mixed forage diet (LCF) with a concentrate to roughage ratio of 46 : 54; 2) high-concentrate corn straw diet (HCS) with a concentrate to roughage ratio of 65 : 35; 3) low-concentrate corn straw diet (LCS) with the same concentrate to roughage ratio (46 : 54) as LCF. The experiment lasted 6 weeks, and samples were collected in the last week. Milk samples were analyzed for conventional components, rumen fluid samples were analyzed for pH and endotoxin, and mammary arterial and venous plasma samples were analyzed for concentrations of interleukin (IL)-1β, IL-6, IL-8 and tumor necrosis factor alpha (TNF-α). Results Concentrations of endotoxin in rumen fluid and feces of cows fed HCS were significantly higher than those of cows fed LCS and LCF. Feeding HCS increased the release of IL-1β, IL-6 and IL-8 in the mammary gland compared with feeding LCS. Concentrations of cytokines (IL-1β and IL-8) in mammary venous plasma had a negative correlation with milk production efficiencies. Conclusions Results indicated that the high-concentrate corn straw diet increased the concentrations of endotoxin in rumen fluid and feces. Furthermore, feeding the high-concentrate corn straw diet stimulated the mammary gland to release more pro-inflammatory cytokines. The results suggest that feeding a high-concentrate corn straw diet induce a higher pro-inflammatory response in the mammary

  16. Mycobacterium tuberculosis heat shock proteins use diverse Toll-like receptor pathways to activate pro-inflammatory signals.

    PubMed

    Bulut, Yonca; Michelsen, Kathrin S; Hayrapetian, Linda; Naiki, Yoshikazu; Spallek, Ralf; Singh, Mahavir; Arditi, Moshe

    2005-06-03

    Although the Toll-like receptors used by Mycobacterium tuberculosis membrane and secreted factors are known, the pathways activated by M. tuberculosis heat shock proteins are not. An efficient immune response against the intracellular pathogen M. tuberculosis is critically dependent on rapid detection of the invading pathogen by the innate immune system and coordinated activation of the adaptive immune response. Macrophage phagocytosis of M. tuberculosis is accompanied by activation of the transcription factor NF-kappaB and secretion of inflammatory mediators that play an important role in granuloma formation and immune protection during M. tuberculosis infection. The interaction between M. tuberculosis and the various Toll-like receptors is complex, and it appears that distinct mycobacterial components may interact with different members of the Toll-like receptor family. Here we show that recombinant, purified, mycobacterial heat shock proteins 65 and 70 induce NF-kappaB activity in a dose-dependent manner in human endothelial cells. Furthermore, we show that whereas mycobacterial heat shock protein 65 signals exclusively through Toll-like receptor 4, heat shock protein 70 also signals through Toll-like receptor 2. Mycobacterial heat shock protein 65-induced NF-kappaB activation was MyD88-, TIRAP-, TRIF-, and TRAM-dependent and required the presence of MD-2. A better understanding of the recognition of mycobacterial heat shock proteins and their role in the host immune response to the pathogen may open the way to a better understanding of the immunological processes induced by this important human pathogen and the host-pathogen interactions and may help in the rational design of more effective vaccines or vaccine adjuvants.

  17. Low physical activity is associated with proinflammatory high-density lipoprotein and increased subclinical atherosclerosis in women with systemic lupus erythematosus.

    PubMed

    Volkmann, Elizabeth R; Grossman, Jennifer M; Sahakian, Lori J; Skaggs, Brian J; FitzGerald, John; Ragavendra, Nagesh; Charles-Schoeman, Christina; Chen, Weiling; Gorn, Alan; Karpouzas, George; Weisman, Michael; Wallace, Daniel J; Hahn, Bevra H; McMahon, Maureen

    2010-02-01

    To investigate the association between physical activity, functional activity of high-density lipoprotein (HDL), and subclinical cardiovascular disease in patients with systemic lupus erythematosus (SLE). A total of 242 SLE patients (all women) participated in this cross-sectional study from February 2004 to February 2008. Carotid plaque and intima-media thickness (IMT), antioxidant function of HDL, and traditional cardiac risk factors were measured. Physical activity was assessed from self-reports by calculating the metabolic equivalents (METS) per week and by the physical function domain of the Medical Outcomes Study Short Form 36 (SF-36). Data were analyzed using bivariate and multivariate regression analyses. Number of METS per week spent performing strenuous exercise was negatively correlated with IMT (r = -0.4, P = 0.002) and number of plaques (r = -0.30, P = 0.0001). Physical function as assessed by the SF-36 was also negatively correlated with IMT (r = -0.14, P = 0.03) and number of plaques (r = -0.14, P = 0.04). In multivariate analyses, number of strenuous exercise METS was significantly associated with IMT (t = -2.2, P = 0.028) and number of plaques (t = -2.5, P = 0.014) when controlling for markers of SLE disease activity and damage, but not after controlling for traditional cardiac risk factors. Low physical activity, defined as <225 total METS per week, was associated with the presence of proinflammatory HDL (P = 0.03). Low physical activity is associated with increased subclinical atherosclerosis and proinflammatory HDL in patients with SLE. Increased strenuous exercise may reduce the risk of atherosclerosis in SLE.

  18. Increased plasma DPP4 activities predict new-onset atherosclerosis in association with its proinflammatory effects in Chinese over a four year period: A prospective study.

    PubMed

    Zheng, T P; Yang, F; Gao, Y; Baskota, A; Chen, T; Tian, H M; Ran, X W

    2014-08-01

    DPP4, a novel proinflammatory cytokine, is involved in the inflammatory process through its interaction with IGF-II/M6P receptor. We aimed to investigate whether it could predict new-onset atherosclerosis in Chinese. A prospective study was conducted of 590 adults (213 men and 377 women) aged 18-70 years without atherosclerosis examined in 2007(baseline) and 2011(follow-up). Circulating DPP4 activity, inflammatory markers, IGF-II/M6P receptor and common carotid artery Intima-Media Thickness (C-IMT) were measured at baseline and four years later. At baseline, individuals in the highest quartile of DPP4 activity had higher age, WHR, BMI, SBP, fasting insulin, 2h-PG, TG, LDL-C, IL-6, hs-CRP, IGF-II/M6P-R, C-IMT and lower HDL-C compared with individuals in the lowest quartile. After a 4-year follow-up, 71 individuals developed atherosclerosis. In multiple linear regression analysis, baseline DPP4 activity was an independent predictor of an increase in inflammatory markers, IGF-II/M6P receptor, and C-IMT over a 4-year period (all P < 0.01). In multivariable-adjusted models, the odds ratio (OR) for incident atherosclerosis comparing the highest with the lowest quartiles of DPP4 activity was 3.17 (95%CI 1.33-7.58) after adjustment for confounding risk factors (P = 0.009). The incidence of atherosclerosis owing to DPP4 activity increased by 12.41%. DPP4 activity is an important predictor of the onset of inflammation and atherosclerosis in apparently healthy Chinese. This finding may have important implications for understanding the proinflammatory role of DPP-4 in the pathogenesis of atherosclerosis. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

  19. Increased GIP signaling induces adipose inflammation via a HIF-1α-dependent pathway and impairs insulin sensitivity in mice.

    PubMed

    Chen, Shu; Okahara, Fumiaki; Osaki, Noriko; Shimotoyodome, Akira

    2015-03-01

    Glucose-dependent insulinotropic polypeptide (GIP) is a gut hormone secreted in response to dietary fat and glucose. The blood GIP level is elevated in obesity and diabetes. GIP stimulates proinflammatory gene expression and impairs insulin sensitivity in cultured adipocytes. In obesity, hypoxia within adipose tissue can induce inflammation. The aims of this study were 1) to examine the proinflammatory effect of increased GIP signaling in adipose tissues in vivo and 2) to clarify the association between GIP and hypoxic signaling in adipose tissue inflammation. We administered GIP intraperitoneally to misty (lean) and db/db (obese) mice and examined adipose tissue inflammation and insulin sensitivity. We also examined the effects of GIP and hypoxia on expression of the GIP receptor (GIPR) gene and proinflammatory genes in 3T3-L1 adipocytes. GIP administration increased monocyte chemoattractant protein-1 (MCP-1) expression and macrophage infiltration into adipose tissue and increased blood glucose in db/db mice. GIPR and hypoxia-inducible factor-1α (HIF-1α) expressions were positively correlated in the adipose tissue in mice. GIPR expression increased dramatically in differentiated adipocytes. GIP treatment of adipocytes increased MCP-1 and interleukin-6 (IL-6) production. Adipocytes cultured either with RAW 264 macrophages or under hypoxia expressed more GIPR and HIF-1α, and GIP treatment increased gene expression of plasminogen activator inhibitor 1 and IL-6. HIF-1α gene silencing diminished both macrophage- and hypoxia-induced GIPR expression and GIP-induced IL-6 expression in adipocytes. Thus, increased GIP signaling plays a significant role in adipose tissue inflammation and thereby insulin resistance in obese mice, and HIF-1α may contribute to this process. Copyright © 2015 the American Physiological Society.

  20. The C-Terminal Module IV of Connective Tissue Growth Factor, Through EGFR/Nox1 Signaling, Activates the NF-κB Pathway and Proinflammatory Factors in Vascular Smooth Muscle Cells

    PubMed Central

    Rodrigues-Diez, Raúl R.; Orejudo, Macarena; Rodrigues-Diez, Raquel; Briones, Ana Maria; Bosch-Panadero, Enrique; Kery, Gyorgy; Pato, Janos; Ortiz, Alberto; Salaices, Mercedes; Egido, Jesus; Ruiz-Ortega, Marta

    2015-01-01

    Abstract Aims: Connective tissue growth factor (CTGF/CCN2) is a developmental gene upregulated in pathological conditions, including cardiovascular diseases, whose product is a matricellular protein that can be degraded to biologically active fragments. Among them, the C-terminal module IV [CCN2(IV)] regulates many cellular functions, but there are no data about redox process. Therefore, we investigated whether CCN2(IV) through redox signaling regulates vascular responses. Results: CCN2(IV) increased superoxide anion (O2•−) production in murine aorta (ex vivo and in vivo) and in cultured vascular smooth muscle cells (VSMCs). In isolated murine aorta, CCN2(IV), via O2•−, increased phenylephrine-induced vascular contraction. CCN2(IV) in vivo regulated several redox-related processes in mice aorta, including increased nonphagocytic NAD(P)H oxidases (Nox)1 activity, protein nitrosylation, endothelial dysfunction, and activation of the nuclear factor-κB (NF-κB) pathway and its related proinflammatory factors. The role of Nox1 in CCN2(IV)-mediated vascular responses in vivo was investigated by gene silencing. The administration of a Nox1 morpholino diminished aortic O2•− production, endothelial dysfunction, NF-κB activation, and overexpression of proinflammatory genes in CCN2(IV)-injected mice. The link CCN2(IV)/Nox1/NF-κB/inflammation was confirmed in cultured VSMCs. Epidermal growth factor receptor (EGFR) is a known CCN2 receptor. In VSMCs, CCN2(IV) activates EGFR signaling. Moreover, EGFR kinase inhibition blocked vascular responses in CCN2(IV)-injected mice. Innovation and Conclusion: CCN2(IV) is a novel prooxidant factor that in VSMCs induces O2•− production via EGFR/Nox1 activation. Our in vivo data demonstrate that CCN2(IV) through EGFR/Nox1 signaling pathway induces endothelial dysfunction and activation of the NF-κB inflammatory pathway. Therefore, CCN2(IV) could be considered a potential therapeutic target for redox-related cardiovascular

  1. ICAM-1-induced expression of proinflammatory cytokines in astrocytes: involvement of extracellular signal-regulated kinase and p38 mitogen-activated protein kinase pathways.

    PubMed

    Lee, S J; Drabik, K; Van Wagoner, N J; Lee, S; Choi, C; Dong, Y; Benveniste, E N

    2000-10-15

    ICAM-1 is a transmembrane glycoprotein of the Ig superfamily involved in cell adhesion. ICAM-1 is aberrantly expressed by astrocytes in CNS pathologies such as multiple sclerosis, experimental allergic encephalomyelitis, and Alzheimer's disease, suggesting a possible role for ICAM-1 in these disorders. ICAM-1 has been shown to be important for leukocyte diapedesis through brain microvessels and subsequent binding to astrocytes. However, other functional roles for ICAM-1 expression on astrocytes have not been well elucidated. Therefore, we investigated the intracellular signals generated upon ICAM-1 engagement on astrocytes. ICAM-1 ligation by a mAb to rat ICAM-1 induced mRNA expression of proinflammatory cytokines such as IL-1alpha, IL-1beta, IL-6, and TNF-alpha. Examination of cytokine protein production revealed that ICAM-1 ligation results in IL-6 secretion by astrocytes, whereas IL-1beta and IL-1alpha protein is expressed intracellularly in astrocytes. The involvement of mitogen-activated protein kinases (MAPKs) in ICAM-1-mediated cytokine expression in astrocytes was tested, as the MAPK extracellular signal-regulated kinase (ERK) was previously shown to be activated upon ICAM-1 engagement. Our results indicate that ERK1/ERK2, as well as p38 MAPK, are activated upon ligation of ICAM-1. Studies using pharmacological inhibitors demonstrate that both p38 MAPK and ERK1/2 are involved in ICAM-1-induced IL-6 expression, whereas only ERK1/2 is important for IL-1alpha and IL-1beta expression. Our data support the role of ICAM-1 on astrocytes as an inflammatory mediator in the CNS and also uncover a novel signal transduction pathway through p38 MAPK upon ICAM-1 ligation.

  2. Increase in the Level of Proinflammatory Cytokine HMGB1 in Nasal Fluids of Patients With Rhinitis and its Sequestration by Glycyrrhizin Induces Eosinophil Cell Death

    PubMed Central

    Cuppari, Caterina; Manti, Sara; Grasso, Luisa; Arrigo, Teresa; Calamai, Luca; Salpietro, Carmelo; Chiarugi, Alberto

    2015-01-01

    Objectives The nuclear protein high mobility group protein box 1 (HMGB1) is a proinflammatory mediator that belongs to the alarmin family of proinflammatory mediators, and it has recently emerged as a key player in different acute and chronic immune disorders. Several lines of evidence demonstrate that HMGB1 is actively released extracellularly from immune cells or passively released from necrotic cells. Because of the ability of HMGB1 to sustain chronic inflammation, we investigated whether the protein is present in nasal fluids of patients with different forms of rhinitis. Methods HMGB1 levels were evaluated in nasal fluids of healthy subjects or rhinitis patients who were treated or not treated with different treatments. Results We report that the level of HMGB1 was significantly increased in nasal fluids of patients with allergic rhinitis, patients with NARES (nonallergic rhinitis with eosinophiliac syndrome), as well as patients with polyps. We also found that a formulation containing the HMGB1-binding compound glycyrrhizin (GLT) reduced the HMGB1 content in nasal fluids of rhinitis patients to an extent similar to that with nasal budesonide treatment. We also found that among the cultured human leukocyte populations, eosinophils released higher amounts of HMGB1. Based on the ability of HMGB1 to sustain eosinophil survival and the ability of GLT to inactivate HMGB1, we report that GLT selectively killed cultured eosinophils and had no effect on neutrophils, macrophages, and lymphocytes. Conclusion Collectively, these data underscore the role of HMGB1 in rhinitis pathogenesis and the therapeutic potential of GLT formulations in treatment of chronic inflammatory disorders of the nasal mucosa. PMID:26045910

  3. PTHrP Interacts With the TGF-β/BMP-2/Gremlin Signaling Pathway to Regulate Pro-inflammatory and Pro-fibrotic Mediators in Pancreatic Acinar and Stellate Cells

    PubMed Central

    Bhatia, Vandanajay; Cao, Yanna; Ko, Tien C.; Falzon, Miriam

    2015-01-01

    Objectives TGF-β regulates immune and fibrotic responses of chronic pancreatitis (CP). The bone morphogenetic protein-2 (BMP-2) antagonist gremlin is regulated by TGF-β. Parathyroid hormone-related hormone (PTHrP) levels are elevated in CP. Here we investigated the crosstalk between TGF-β/BMP-2/gremlin and PTHrP signaling. Methods Reverse transcription/real-time PCR, ChIP, Western blotting, and transient transfection were used to investigate PTHrP regulation by TGF-β and BMP-2, and gremlin regulation by PTHrP. The PTHrP antagonist PTHrP (7-34) and acinar cells with conditional Pthrp gene deletion (PTHrPΔacinar) were used to assess PTHrP’s role in the pro-inflammatory and pro-fibrotic effects of TGF-β and gremlin. Results TGF-β increased PTHrP levels in acinar cells and pancreatic stellate cells (PSCs) through a Smad3-dependent pathway. TGF-β’s effects on levels of IL-6 and ICAM-1(acinar cells) and procollagen I and fibronectin (PSCs) were inhibited by PTHrP (7-34). PTHrPΔacinar suppressed TGF-β’s effects on IL-6 and ICAM-1. PTHrP increased gremlin in acinar cells, and inhibiting gremlin action suppressed TGF-β’s and PTHrP’s effects on IL-6 and ICAM-1. TGF-β-mediated gremlin upregulation was suppressed in PTHrPΔacinar cells. BMP-2 suppressed PTHrP levels in PSCs. Conclusions PTHrP functions as a novel mediator of the pro-inflammatory and pro-fibrotic effects of TGF-β. TGF-β and BMP-2 regulate PTHrP expression and PTHrP regulates gremlin levels. PMID:26495794

  4. Parathyroid Hormone-Related Protein Interacts With the Transforming Growth Factor-β/Bone Morphogenetic Protein-2/Gremlin Signaling Pathway to Regulate Proinflammatory and Profibrotic Mediators in Pancreatic Acinar and Stellate Cells.

    PubMed

    Bhatia, Vandanajay; Cao, Yanna; Ko, Tien C; Falzon, Miriam

    2016-01-01

    Transforming growth factor β (TGF-β) regulates immune and fibrotic responses of chronic pancreatitis. The bone morphogenetic protein 2 (BMP-2) antagonist gremlin is regulated by TGF-β. Parathyroid hormone-related protein (PTHrP) levels are elevated in chronic pancreatitis. Here, we investigated the cross-talk between TGF-β/BMP-2/gremlin and PTHrP signaling. Reverse transcription/real-time polymerase chain reaction, chromatin immunoprecipitation, Western blotting, and transient transfection were used to investigate PTHrP regulation by TGF-β and BMP-2 and gremlin regulation by PTHrP. The PTHrP antagonist PTHrP (7-34) and acinar cells with conditional Pthrp gene deletion (PTHrP) were used to assess PTHrP's role in the proinflammatory and profibrotic effects of TGF-β and gremlin. Transforming growth factor β increased PTHrP levels in acinar cells and pancreatic stellate cells (PSCs) through a Smad3-dependent pathway. Transforming growth factor β's effects on levels of IL-6 and intercellular adhesion molecule 1 (ICAM-1) (acinar cells) and procollagen I and fibronectin (PSCs) were inhibited by PTHrP (7-34). PTHrP suppressed TGF-β's effects on IL-6 and ICAM-1. Parathyroid hormone-related hormone increased gremlin in acinar cells, and inhibiting gremlin action suppressed TGF-β's and PTHrP's effects on IL-6 and ICAM-1. Transforming growth factor β-mediated gremlin up-regulation was suppressed in PTHrP cells. Bone morphogenetic protein 2 suppressed PTHrP levels in PSCs. Parathyroid hormone-related hormone functions as a novel mediator of the proinflammatory and profibrotic effects of TGF-β. Transforming growth factor β and BMP-2 regulate PTHrP expression, and PTHrP regulates gremlin levels.

  5. Rosiglitazone negatively regulates c-Jun N-terminal kinase and toll-like receptor 4 proinflammatory signalling during initiation of experimental aortic aneurysms.

    PubMed

    Pirianov, Grisha; Torsney, Evelyn; Howe, Franklyn; Cockerill, Gillian W

    2012-11-01

    Development and rupture of aortic aneurysms (AA) is a complex process involving inflammation, cell death, tissue and matrix remodelling. The thiazolidinediones (TZDs) including Rosiglitazone (RGZ) are a family of drugs which act as agonists of the nuclear peroxisome proliferator-activated receptors and have a broad spectrum of effects on a number of biological processes in the cardiovascular system. In our previous study we have demonstrated that RGZ has a marked effect on both aneurysm rupture and development, however, the precise mechanism of this is unknown. In the present study, we examined possible targets of RGZ action in the early stages of Angiotensin II-induced AA in apolipoprotein E-deficient mice. For this purpose we employed immunoblotting, ELISA and antibody array approaches. We found that RGZ significantly inhibited c-Jun N-terminal kinase (JNK) phosphorylation and down-regulated toll-like receptor 4 (TLR4) expression at the site of lesion formation in response to Angiotensin II infusion in the initiation stage (6-72 h) of experimental AA development. Importantly, this effect was also associated with a decrease of CD4 antigen and reduction in production of TLR4/JNK-dependant proinflammatory chemokines MCP-1 and MIP-1α. These data suggest that RGZ can modulate inflammatory processes by blocking TLR4/JNK signalling in initiation stages of AA development. Copyright © 2012 Elsevier Ireland Ltd. All rights reserved.

  6. Veronicastrum axillare Alleviates Lipopolysaccharide-Induced Acute Lung Injury via Suppression of Proinflammatory Mediators and Downregulation of the NF-κB Signaling Pathway

    PubMed Central

    Ma, Quanxin; Yang, Qinqin; Ping, Shun; Shou, Qiyang; Zhou, Weimin

    2016-01-01

    Veronicastrum axillare is a traditional medical plant in China which is widely used in folk medicine due to its versatile biological activities, especially for its anti-inflammatory effects. However, the detailed mechanism underlying this action is not clear. Here, we studied the protective effects of V. axillare against acute lung injury (ALI), and we further explored the pharmacological mechanisms of this action. We found that pretreatment with V. axillare suppressed the release of proinflammatory cytokines in the serum of ALI mice. Histological analysis of lung tissue demonstrated that V. axillare inhibited LPS-induced lung injury, improved lung morphology, and reduced the activation of nuclear factor-κB (NF-κB) in the lungs. Furthermore, the anti-inflammatory actions of V. axillare were investigated in vitro. We observed that V. axillare suppressed the mRNA expression of interleukin-1β (IL-1β), IL-6, monocyte chemotactic protein-1 (MCP-1), cyclooxygenase-2 (COX-2), and tumor necrosis factor-α (TNF-α) in RAW264.7 cells challenged with LPS. Furthermore, pretreatment of V. axillare in vitro reduced the phosphorylation of p65 and IκB-α which is activated by LPS. In conclusion, our data firstly demonstrated that the anti-inflammatory effects of V. axillare against ALI were achieved through downregulation of the NF-κB signaling pathway, thereby reducing the production of inflammatory mediators. PMID:27890971

  7. Costly Signaling Increases Trust, Even Across Religious Affiliations.

    PubMed

    Hall, Deborah L; Cohen, Adam B; Meyer, Kaitlin K; Varley, Allison H; Brewer, Gene A

    2015-09-01

    Trust is a critical aspect of social interaction. One might predict that individuals trust religious out-groups less than religious in-groups, and that costly signals performed by members of religious in-groups increase trust while costly signals performed by members of religious out-groups decrease trust. We examined how Christian participants perceived the trustworthiness of Muslim and Christian individuals who did or did not engage in religious costly signaling. Religious costly signaling, operationalized as giving to religious charities (Experiments 1 and 2) or adhering to religious dietary restrictions (Experiment 3), increased self-reported trust, regardless of target religious affiliation. Furthermore, when estimating the likelihood that trustworthy versus untrustworthy targets engaged in costly signaling, participants made systematic judgments that showed that costly signaling is associated with trust for both Muslim and Christian targets (Experiment 4). These results are novel in their suggestion that costly signals of religious commitment can increase trust both within and, crucially, across religious-group lines.

  8. VEGFR-2 reduces while combined VEGFR-2 and -3 signaling increases inflammation in apical periodontitis

    PubMed Central

    Virtej, Anca; Papadakou, Panagiota; Sasaki, Hajime; Bletsa, Athanasia; Berggreen, Ellen

    2016-01-01

    Background In apical periodontitis, oral pathogens provoke an inflammatory response in the apical area that induces bone resorptive lesions. In inflammation, angio- and lymphangiogenesis take place. Vascular endothelial growth factors (VEGFs) and their receptors (VEGFRs) are key players in these processes and are expressed in immune cells and endothelial cells in the lesions. Objective We aimed at testing the role of VEGFR-2 and -3 in periapical lesion development and investigated their role in lymphangiogenesis in the draining lymph nodes. Design We induced lesions by pulp exposure in the lower first molars of C57BL/6 mice. The mice received IgG injections or blocking antibodies against VEGFR-2 (anti-R2), VEGFR-3 (anti-R3), or combined VEGFR-2 and -3, starting on day 0 until day 10 or 21 post-exposure. Results Lesions developed faster in the anti-R2 and anti-R3 group than in the control and anti-R2/R3 groups. In the anti-R2 group, a strong inflammatory response was found expressed as increased number of neutrophils and osteoclasts. A decreased level of pro-inflammatory cytokines was found in the anti-R2/R3 group. Lymphangiogenesis in the draining lymph nodes was inhibited after blocking of VEGFR-2 and/or -3, while the largest lymph node size was seen after anti-R2 treatment. Conclusions We demonstrate an anti-inflammatory effect of VEGFR-2 signaling in periapical lesions which seems to involve neutrophil regulation and is independent of angiogenesis. Combined signaling of VEGFR-2 and -3 has a pro-inflammatory effect. Lymph node lymphangiogenesis is promoted through activation of VEGFR-2 and/or VEGFR-3. PMID:27650043

  9. Pro-inflammatory macrophages increase in skeletal muscle of high fat-fed mice and correlate with metabolic risk markers in humans.

    PubMed

    Fink, Lisbeth N; Costford, Sheila R; Lee, Yun S; Jensen, Thomas E; Bilan, Philip J; Oberbach, Andreas; Blüher, Matthias; Olefsky, Jerrold M; Sams, Anette; Klip, Amira

    2014-03-01

    In obesity, immune cells infiltrate adipose tissue. Skeletal muscle is the major tissue of insulin-dependent glucose disposal, and indices of muscle inflammation arise during obesity, but whether and which immune cells increase in muscle remain unclear. Immune cell presence in quadriceps muscle of wild type mice fed high-fat diet (HFD) was studied for 3 days to 10 weeks, in CCL2-KO mice fed HFD for 1 week, and in human muscle. Leukocyte presence was assessed by gene expression of lineage markers, cyto/chemokines and receptors; immunohistochemistry; and flow cytometry. After 1 week HFD, concomitantly with glucose intolerance, muscle gene expression of Ly6b, Emr1 (F4/80), Tnf, Ccl2, and Ccr2 rose, as did pro- and anti-inflammatory markers Itgax (CD11c) and Mgl2. CD11c+ proinflammatory macrophages in muscle increased by 76%. After 10 weeks HFD, macrophages in muscle increased by 47%. Quadriceps from CCL2-KO mice on HFD did not gain macrophages and maintained insulin sensitivity. Muscle of obese, glucose-intolerant humans showed elevated CD68 (macrophage marker) and ITGAX, correlating with poor glucose disposal and adiposity. Mouse and human skeletal muscles gain a distinct population of inflammatory macrophages upon HFD or obesity, linked to insulin resistance in humans and CCL2 availability in mice. © 2013 The Obesity Society.

  10. Cyclic exercise induces anti-inflammatory signal molecule increases in the plasma of Parkinson's patients.

    PubMed

    Cadet, Patrick; Zhu, Wei; Mantione, Kirk; Rymer, Marilyn; Dardik, Irving; Reisman, Stan; Hagberg, Sean; Stefano, George B

    2003-10-01

    It has been known for many years that immune system alterations occur with Parkinson's disease (PD). Changes in lymphocyte populations in cerebrospinal fluid and blood, immunoglobulin synthesis, and cytokine and acute phase protein production have been observed in patients with PD. Hence, there is evidence for inflammation. In this report we demonstrate that cyclic exercise over months results in a significant increase in the rise of plasma anti-inflammatory signal molecules, such as interleukin-10 and adrenocorticotropin. Additionally, endogenous plasma morphine levels increase with the duration of the cyclic exercise protocol. Morphine is identified and quantified by high performance liquid chromatography coupled to electrochemical detection and nano electro-spray ionization double quadrupole orthogonal acceleration time of flight mass spectrometry. Proinflammatory cytokine, i.e., interleukin-1, interleukin-6, plasma levels did not increase. These results matched with those reported previously, demonstrating enhanced motor skills and mood elevation with this cyclic exercise protocol, suggest that this protocol induces the formation of anti-inflammatory signal molecules, which appear to be associated with alleviation of some of the clinical characteristics of PD.

  11. Increased expression of IL-37 in patients with Graves' disease and its contribution to suppression of proinflammatory cytokines production in peripheral blood mononuclear cells.

    PubMed

    Li, Yanqun; Wang, Zi; Yu, Ting; Chen, Bingni; Zhang, Jinshun; Huang, Kunzhao; Huang, Zhong

    2014-01-01

    Interleukin-37 (IL-37), a member of IL-1 family, is primarily an anti-inflammatory cytokine, which reduces systemic and local inflammation. However, the expression and role of IL-37 in Graves' disease (GD) remains unknown. This study aims to measure the levels of serum and peripheral blood mononuclear cells (PBMCs) IL-37 in patients with Graves' disease and to examine its association with disease activity. Furthermore, we investigate the effect of IL-37 on proinflammatory cytokines involved in the pathogenesis of GD. The expressions of IL-37, TNF-α, IL-6, and IL-17 mRNA in peripheral blood mononuclear cells (PBMCs) of 40 patients with Graves' disease were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR), and the levels of IL-37, TNF-α, IL-6, and IL-17 in serum were detected by enzyme-linked immunoassay (ELISA). The correlation of serum IL-37 levels with cytokines and disease activity in Graves' disease patients were investigated. The expressions of cytokines TNF-α, IL-6, and IL-17 in PBMCs under recombinant IL-37 stimulation were determined by RT-PCR and ELISA respectively. The levels of IL-37, TNF-α, IL-6, and IL-17 in PBMCs and serum were significantly increased in patients with GD compared with healthy controls (HC). Serum IL-37 were closely correlated with TNF-α, IL-6, IL-17, thyrotropin (TSH), free thyroxine (FT4),free triiodothyronine (FT3) and thyrotropin receptor antibody (TRAB). GD patients with active disease showed higher IL-37 mRNA and serum protein levels compared with those with inactive disease as well as HC. Moreover, IL-37 suppressed the production of IL-6, IL-17 and TNF-α in PBMCs of patients with GD. Increased level of IL-37 in patients with GD are associated with TNF-α, IL-6, IL-17 and disease activity, and it plays a protective role against inflammatory effect in GD by inhibiting the production of proinflammatory cytokines. Thus, IL-37 may provide a novel research target for the pathogenesis and therapy of

  12. Increased Expression of IL-37 in Patients with Graves' Disease and Its Contribution to Suppression of Proinflammatory Cytokines Production in Peripheral Blood Mononuclear Cells

    PubMed Central

    Li, Yanqun; Wang, Zi; Yu, Ting; Chen, Bingni; Zhang, Jinshun; Huang, Kunzhao; Huang, Zhong

    2014-01-01

    Background Intreleukin-37 (IL-37), a member of IL-1 family, is primarily an anti-inflammatory cytokine, which reduces systemic and local inflammation. However, the expression and role of IL-37 in Graves' disease (GD) remains unknown. This study aims to measure the levels of serum and peripheral blood mononuclear cells (PBMCs) IL-37 in patients with Graves' disease and to examine its association with disease activity. Furthermore, we investigate the effect of IL-37 on proinflammatory cytokines involved in the pathogenesis of GD. Methods The expressions of IL-37, TNF-α, IL-6, and IL-17 mRNA in peripheral blood mononuclear cells (PBMCs) of 40 patients with Graves' disease were determined by real-time reverse transcription-polymerase chain reaction (RT-PCR), and the levels of IL-37, TNF-α, IL-6, and IL-17 in serum were detected by enzyme-linked immunoassay (ELISA). The correlation of serum IL-37 levels with cytokines and disease activity in Graves' disease patients were investigated. The expressions of cytokines TNF-α, IL-6, and IL-17 in PBMCs under recombinant IL-37 stimulation were determined by RT-PCR and ELISA respectively. Results The levels of IL-37, TNF-α, IL-6, and IL-17 in PBMCs and serum were significantly increased in patients with GD compared with healthy controls (HC). Serum IL-37 were closely correlated with TNF-α, IL-6, IL-17, thyrotropin (TSH), free thyroxine (FT4),free triiodothyronine (FT3) and thyrotropin receptor antibody (TRAB). GD patients with active disease showed higher IL-37 mRNA and serum protein levels compared with those with inactive disease as well as HC. Moreover, IL-37 suppressed the production of IL-6, IL-17 and TNF-α in PBMCs of patients with GD. Conclusions Increased level of IL-37 in patients with GD are associated with TNF-α, IL-6, IL-17 and disease activity, and it plays a protective role against inflammatory effect in GD by inhibiting the production of proinflammatory cytokines. Thus, IL-37 may provide a novel research

  13. Partial Seizures Are Associated with Early Increases in Signal Complexity

    PubMed Central

    Jouny, Christophe C; Bergey, Gregory K; Franaszczuk, Piotr J

    2009-01-01

    Objectives Partial seizures are often believed to be associated with EEG signals of low complexity because seizures are associated with increased neural network synchrony. The investigations reported here provide an assessment of the signal complexity of epileptic seizure onsets using newly developed quantitative measures. Methods Using the Gabor atom density (GAD) measure of signal complexity, 339 partial seizures in 45 patients with intracranial electrode arrays were analyzed. Segmentation procedures were applied to determine the timing and amplitude of GAD changes relative to the electrographic onset of the seizure. Results 330 out of 339 seizures have significant complexity level changes, with 319 (97%) having an increase in complexity. GAD increases occur within seconds of the onset of the partial seizure but are not observed in channels remote from the focus. The complexity increase is similar for seizures from mesial temporal origin, neocortical temporal and extra-temporal origin. Conclusions Partial onset seizures are associated with early increases in signal complexity as measured by GAD. This increase is independent of the location of the seizure focus. Significance Despite the often predominant rhythmic activity that characterizes onset and early evolution of epileptic seizures, partial seizure onset is associated with an early increase in complexity. These changes are common to partial seizures originating from different brain regions, indicating a similar seizure dynamic. PMID:19910249

  14. Distinctive pro-inflammatory gene signatures induced in articular chondrocytes by oncostatin M and IL-6 are regulated by Suppressor of Cytokine Signaling-3.

    PubMed

    Liu, X; Liu, R; Croker, B A; Lawlor, K E; Smyth, G K; Wicks, I P

    2015-10-01

    To describe gene expression in murine chondrocytes stimulated with IL-6 family cytokines and the impact of deleting Suppressor of Cytokine Signaling-3 (SOCS-3) in this cell type. Primary chondrocytes were isolated from wild type and SOCS-3-deficient (Socs3(Δ/Δcol2)) mice and stimulated with oncostatin M (OSM), IL-6 plus the soluble IL-6 receptor (IL-6/sIL-6R), IL-11 or leukemia inhibitory factor (LIF) for 4 h. Total RNA was extracted and gene expression was evaluated by microarray analysis. Validation of the microarray results was performed using Taqman probes on RNA derived from chondrocytes stimulated for 1, 2, 4 or 8 h. Gene ontology was characterized using DAVID (database for annotation, visualization and integrated discovery). Multiple genes, including Bcl3, Junb, Tgm1, Angptl4 and Lrg1, were upregulated in chondrocytes stimulated with each gp130 cytokine. The gene transcription profile in response to OSM stimulation was pro-inflammatory and was highly correlated to IL-6/sIL-6R, rather than IL-11 or LIF. In the absence of SOCS-3, OSM and IL-6/sIL-6R stimulation induced an interferon (IFN)-like gene signature, including expression of IL-31ra and S100a9. While each gp130 cytokine induced a transcriptional response in chondrocytes, OSM- and IL-6/sIL-6R were the most potent members of this cytokine family. SOCS-3 plays an important regulatory role in this cell type, as it does in hematopoietic cells. Our results provide new insights into a hierarchy of gp130-induced transcriptional responses in chondrocytes that is normally restrained by SOCS-3 and suggest therapeutic inhibition of OSM may have benefit over and above antagonism of IL-6 during inflammatory arthritis. Copyright © 2015 Osteoarthritis Research Society International. Published by Elsevier Ltd. All rights reserved.

  15. Particle Pollution in Rio de Janeiro, Brazil: Increase and Decrease of Pro-inflammatory Cytokines IL-6 and IL-8 in Human Lung Cells

    PubMed Central

    Rodríguez-Cotto, Rosa I.; Ortiz-Martínez, Mario G.; Rivera-Ramírez, Evasomary; Mateus, Vinicius L.; Amaral, Beatriz S.; Jiménez-Vélez, Braulio D.; Gioda, Adriana

    2015-01-01

    Particle pollution from urban and industrialized regions in Rio de Janeiro (RJ), Brazil was analyzed for toxic and pro-inflammatory (cytokines: IL-6, IL-8, IL-10) responses in human bronchial epithelial cells. Trace elements contribution was studied. Airborne particulate matter was collected at: three industrial sites Ind-1 (PM10) and Ind-2a and 2b (PM2.5); Centro urban area (PM10) and two rural sites (PM2.5, PM10). PM10 acetone extracts were toxic and did not elicit cytokine release; aqueous extracts were less toxic and stimulated the release of IL-6 and IL-8. PM2.5 aqueous extracts from Ind-2 decreased the release of IL-6 and IL-8. Zinc concentration was higher at the industrial and rural reference sites (Ref-1-2) although metals were not associated to cytokines changes. These results demonstrate that PM from RJ can either increase or decrease cytokine secretion in vitro while being site specific and time dependent. PMID:25106047

  16. Insulin Resistance Promotes Early Atherosclerosis via Increased Proinflammatory Proteins and Oxidative Stress in Fructose-Fed ApoE-KO Mice

    PubMed Central

    Cannizzo, Beatriz; Luján, Agustín; Estrella, Natalia; Lembo, Carina; Cruzado, Montserrat; Castro, Claudia

    2012-01-01

    High fructose intake induces an insulin resistance state associated with metabolic syndrome (MS). The effect of vascular inflammation in this model is not completely addressed. The aim of this study was to evaluate vascular remodeling, inflammatory and oxidative stress markers, and atheroma development in high-fructose diet-induced insulin resistance of ApoE-deficient mice (ApoE-KO). Mice were fed with either a normal chow or a 10% w/v fructose (HF) in drinking water over a period of 8 weeks. Thereafter, plasma metabolic parameters, vascular remodeling, atheroma lesion size, inflammatory markers, and NAD(P)H oxidase activity in the arteries were determined. HF diet induced a marked increase in plasma glucose, insulin, and triglycerides in ApoE-KO mice, provoked vascular remodeling, enhanced expression of vascular cell-adhesion molecule-1 (VCAM-1) and matrix metalloprotease 9 (MMP-9) and enlarged atherosclerotic lesion in aortic and carotid arteries. NAD(P)H oxidase activity was enhanced by fructose intake, and this effect was attenuated by tempol, a superoxide dismutase mimetic, and losartan, an Angiotensin II receptor antagonist. Our study results show that high-fructose-induced insulin resistance promotes a proinflammatory and prooxidant state which accelerates atherosclerotic plaque formation in ApoE-KO mice. PMID:22474431

  17. Chemical intervention in plant sugar signalling increases yield and resilience

    NASA Astrophysics Data System (ADS)

    Griffiths, Cara A.; Sagar, Ram; Geng, Yiqun; Primavesi, Lucia F.; Patel, Mitul K.; Passarelli, Melissa K.; Gilmore, Ian S.; Steven, Rory T.; Bunch, Josephine; Paul, Matthew J.; Davis, Benjamin G.

    2016-12-01

    The pressing global issue of food insecurity due to population growth, diminishing land and variable climate can only be addressed in agriculture by improving both maximum crop yield potential and resilience. Genetic modification is one potential solution, but has yet to achieve worldwide acceptance, particularly for crops such as wheat. Trehalose-6-phosphate (T6P), a central sugar signal in plants, regulates sucrose use and allocation, underpinning crop growth and development. Here we show that application of a chemical intervention strategy directly modulates T6P levels in planta. Plant-permeable analogues of T6P were designed and constructed based on a ‘signalling-precursor’ concept for permeability, ready uptake and sunlight-triggered release of T6P in planta. We show that chemical intervention in a potent sugar signal increases grain yield, whereas application to vegetative tissue improves recovery and resurrection from drought. This technology offers a means to combine increases in yield with crop stress resilience. Given the generality of the T6P pathway in plants and other small-molecule signals in biology, these studies suggest that suitable synthetic exogenous small-molecule signal precursors can be used to directly enhance plant performance and perhaps other organism function.

  18. Chromofungin (CHR: CHGA47-66) is downregulated in persons with active ulcerative colitis and suppresses pro-inflammatory macrophage function through the inhibition of NF-κB signaling.

    PubMed

    Eissa, Nour; Hussein, Hayam; Kermarrec, Laëtitia; Elgazzar, Omar; Metz-Boutigue, Marie-Helene; Bernstein, Charles N; Ghia, Jean-Eric

    2017-08-19

    Chromogranin-A (CHGA) is a prohormone secreted by neuroendocrine cells and is a precursor of several bioactive peptides, which are implicated in different and distinctive biological and immune functions. Chromofungin (CHR: CHGA47-66) is a short peptide with antimicrobial effects and encodes from CHGA exon-IV. Inflammatory bowel disease (IBD) is characterized by alterations in the activation of pro-inflammatory pathways, pro-inflammatory macrophages (M1), and nuclear transcription factor kappa B (NF-κB) signaling leading to the perpetuation of the inflammatory process. Here, we investigated the activity of CHR (CHGA Exon-IV) in persons with active ulcerative colitis (UC) and the underlying mechanisms in dextran sulfate sodium (DSS)-colitis in regard to macrophages activation and migration. Tissue mRNA expression of CHR (CHGA Exon-IV) was down regulated in active UC compared to healthy individuals and negatively correlated with pro-inflammatory macrophages (M1) cytokines, toll-like receptors (TLR)-4, and pNF-κB activity. In DSS colitis, CHR (CHGA Exon-IV) expression was reduced, and exogenous CHR treatment decreased the severity of colitis associated with a reduction of M1 macrophages markers and pNF-κB. In vitro, CHR treatment reduced macrophages migration, decreased pro-inflammatory cytokines production and pNF-κB. Targeting CHR may represent a promising new direction in research to define new therapeutic targets and biomarkers associated with IBD. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Red wine intake but not other alcoholic beverages increases total antioxidant capacity and improves pro-inflammatory profile after an oral fat diet in healthy volunteers.

    PubMed

    Torres, A; Cachofeiro, V; Millán, J; Lahera, V; Nieto, M L; Martín, R; Bello, E; Alvarez-Sala, L A

    2015-12-01

    Different alcoholic beverages exert different effects on inflammation and oxidative stress but these results are controversial and scanty in some aspects. We analyze the effect of different alcoholic beverages after a fat-enriched diet on lipid profile, inflammatory factors and oxidative stress in healthy people in a controlled environment. We have performed a cross-over design in five different weeks. Sixteen healthy volunteers have received the same oral fat-enriched diet (1486kcal/m(2)) and a daily total amount of 16g/m(2) of alcohol, of different beverages (red wine, vodka, brandy or rum) and equivalent caloric intakes as sugar with water in the control group. We have measured the levels of serum lipids, high sensitivity C-reactive protein (hsCRP), tumor necrosis factor α (TNFα), interleukin 6 (IL-6), soluble phospholipase A2 (sPLA2), lipid peroxidation (LPO) and total antioxidant capacity (TAC). Red wine intake was associated with decreased of mean concentrations of hsCRP, TNFα and IL-6 induced by fat-enriched diet (p<0.05); nevertheless, sPLA2 concentrations were not significantly modified. After a fat-enriched diet added with red wine, TAC increased as compared to the same diet supplemented with rum, brandy, vodka or the control (water with sugar) (p<0.05). Moderate red wine intake, but not other alcoholic beverages, decreased pro-inflammatory factors and increased total antioxidant capacity despite a fat-enriched diet intake in healthy young volunteers. Copyright © 2015 Elsevier España, S.L.U. y Sociedad Española de Medicina Interna (SEMI). All rights reserved.

  20. Burkholderia Diffusible Signal Factor Signals to Francisella novicida To Disperse Biofilm and Increase Siderophore Production.

    PubMed

    Dean, Scott N; Chung, Myung-Chul; van Hoek, Monique L

    2015-10-01

    In many bacteria, the ability to modulate biofilm production relies on specific signaling molecules that are either self-produced or made by neighboring microbes within the ecological niche. We analyzed the potential interspecies signaling effect of the Burkholderia diffusible signal factor (BDSF) on Francisella novicida, a model organism for Francisella tularensis, and demonstrated that BDSF both inhibits the formation and causes the dispersion of Francisella biofilm. Specificity was demonstrated for the cis versus the trans form of BDSF. Using transcriptome sequencing, quantitative reverse transcription-PCR, and activity assays, we found that BDSF altered the expression of many F. novicida genes, including genes involved in biofilm formation, such as chitinases. Using a chitinase inhibitor, the antibiofilm activity of BDSF was also shown to be chitinase dependent. In addition, BDSF caused an increase in RelA expression and increased levels of (p)ppGpp, leading to decreased biofilm production. These results support our observation that exposure of F. novicida to BDSF causes biofilm dispersal. Furthermore, BDSF upregulated the genes involved in iron acquisition (figABCD), increasing siderophore production. Thus, this study provides evidence for a potential role and mechanism of diffusible signal factor (DSF) signaling in the genus Francisella and suggests the possibility of interspecies signaling between Francisella and other bacteria. Overall, this study suggests that in response to the interspecies DSF signal, F. novicida can alter its gene expression and regulate its biofilm formation. Copyright © 2015, American Society for Microbiology. All Rights Reserved.

  1. Sweet potato [Ipomoea batatas (L.) Lam. "Tainong 57"] starch improves insulin sensitivity in high-fructose diet-fed rats by ameliorating adipocytokine levels, pro-inflammatory status, and insulin signaling.

    PubMed

    Chen, Ya-Yen; Lai, Ming-Hoang; Hung, Hsin-Yu; Liu, Jen-Fang

    2013-01-01

    The aim of this study was to investigate the effects of low-glycemic index (GI) sweet potato starch on adipocytokines, pro-inflammatory status, and insulin signaling in the high-fructose diet-induced insulin-resistant rat. We randomly divided 24 insulin-resistant rats and 16 normal rats into two groups fed a diet containing 575 g/kg of starch: a low-GI sweet potato starch (S) or a high-GI potato starch (P). The four experimental groups were labeled as follows: insulin-resistant P (IR-P), insulin-resistant S (IR-S), normal P (N-P) and normal S (N-S). After 4 wk on the experimental diets, an intraperitoneal glucose tolerance test (IPGTT) was conducted, and the homeostasis model assessment (HOMA), adipocytokines, pro-inflammatory cytokines levels, and insulin signaling-related protein expression were measured. The homeostasis model assessment values were significantly lower in the IR-S than in the IR-P group, suggesting that insulin sensitivity was improved among sweet potato starch-fed rats. Levels of tumor necrosis factor-α, interleukin-6, resistin, and retinol binding protein-4 were significantly lower in the IR-S versus the IR-P group, indicating an improvement of pro-inflammatory status in sweet potato starch-fed rats. The sweet potato starch diet also significantly enhanced the protein expression of phospho-Tyr-insulin receptor substrate-1 and improved the translocation of glucose transporter 4 in the skeletal muscle. Our results illustrated that sweet potato starch feeding for 4 wk can improve insulin sensitivity in insulin-resistant rats, possibly by improving the adipocytokine levels, pro-inflammatory status, and insulin signaling.

  2. Induction of a Proinflammatory Response in Cortical Astrocytes by the Major Metabolites Accumulating in HMG-CoA Lyase Deficiency: the Role of ERK Signaling Pathway in Cytokine Release.

    PubMed

    Fernandes, Carolina Gonçalves; Rodrigues, Marília Danyelle Nunes; Seminotti, Bianca; Colín-González, Ana Laura; Santamaria, Abel; Quincozes-Santos, André; Wajner, Moacir

    2016-08-01

    3-Hydroxy-3-methylglutaric aciduria (HMGA) is an inherited metabolic disorder caused by 3-hydroxy-3-methylglutaryl-CoA lyase deficiency. It is biochemically characterized by predominant tissue accumulation and high urinary excretion of 3-hydroxy-3-methylglutarate (HMG) and 3-methylglutarate (MGA). Affected patients commonly present acute symptoms during metabolic decompensation, including vomiting, seizures, and lethargy/coma accompanied by metabolic acidosis and hypoketotic hypoglycemia. Although neurological manifestations are common, the pathogenesis of brain injury in this disease is poorly known. Astrocytes are important for neuronal protection and are susceptible to damage by neurotoxins. In the present study, we investigated the effects of HMG and MGA on important parameters of redox homeostasis and cytokine production in cortical cultured astrocytes. The role of the metabolites on astrocyte mitochondrial function (thiazolyl blue tetrazolium bromide (MTT) reduction) and viability (propidium iodide incorporation) was also studied. Both organic acids decreased astrocytic mitochondrial function and the concentrations of reduced glutathione without altering cell viability. In contrast, they increased reactive species formation (2'-7'-dichlorofluorescein diacetate (DCFHDA) oxidation), as well as IL-1β, IL-6, and TNF α release through the ERK signaling pathway. Taken together, the data indicate that the principal compounds accumulating in HMGA induce a proinflammatory response in cultured astrocytes that may possibly be involved in the neuropathology of this disease.

  3. Age-associated Pro-inflammatory Remodeling and Functional Phenotype in the Heart and Large Arteries

    PubMed Central

    Wang, Mingyi; Shah, Ajay M

    2015-01-01

    The aging population is increasing dramatically. Aging–associated stress simultaneously drives proinflammatory remodeling, involving angiotensin II and other factors, in both the heart and large arteries. The structural remodeling and functional changes that occur with aging include cardiac and vascular wall stiffening, systolic hypertension and suboptimal ventricular-arterial coupling, features that are often clinically silent and thus termed a silent syndrome. These age-related effects are the result of responses initiated by cardiovascular proinflammatory cells. Local proinflammatory signals are coupled between the heart and arteries due to common mechanical and humoral messengers within a closed circulating system. Thus, targeting proinflammatory signaling molecules would be a promising approach to improve age-associated suboptimal ventricular-arterial coupling, a major predisposing factor for the pathogenesis of clinical cardiovascular events such as heart failure. PMID:25665458

  4. MMP1-1607 polymorphism increases the risk for periapical lesion development through the upregulation MMP-1 expression in association with pro-inflammatory milieu elements

    PubMed Central

    TROMBONE, Ana Paula Favaro; CAVALLA, Franco; SILVEIRA, Elcia Maria Varize; ANDREO, Camile Bermejo; FRANCISCONI, Carolina Favaro; FONSECA, Angélica Cristina; LETRA, Ariadne; SILVA, Renato Menezes; GARLET, Gustavo Pompermaier

    2016-01-01

    ABSTRACT Increased matrix metalloproteinases (MMPs) activity is a hallmark of periapical granulomas. However, the factors underlying the MMPs expression modulation in healthy and diseased periapical tissues remains to be determined. Objective In this study, we evaluated the association between the MMP1-1607 polymorphism (rs1799750) and pro-inflammatory milieu elements with MMP-1 mRNA levels in vivo. Material and Methods MMP1-1607 SNP and the mRNA levels of MMP-1, TNF-a, IFN-g, IL-17A, IL-21, IL-10, IL-4, IL-9, and FOXp3 were determined via RealTimePCR in DNA/RNA samples from patients presenting periapical granulomas (N=111, for both genotyping and expression analysis) and control subjects (N=214 for genotyping and N=26 for expression analysis). The Shapiro-Wilk, Fisher, Pearson, Chi-square ordinal least squares regression tests were used for data analysis (p<0.05 was considered statistically significant). Results The MMP1-1607 1G/2G and 1G/2G+2G/2G genotypes were significantly more prevalent in the patients than in controls, comprising a risk factor for periapical lesions development. MMP-1 mRNA levels were higher in periapical lesions than in healthy periodontal ligament samples, as well as higher in active than in inactive lesions. The polymorphic allele 2G carriers presented a significantly higher MMP-1 mRNA expression when compared with the 1G/1G genotype group. The ordered logistic regression demonstrated a significant correlation between the genetic polymorphism and the expression levels of MMP-1. Additionally, the pro- and anti-inflammatory cytokines IL-17A, IFN-g, TNF-a, IL-21, IL-10, IL-9, and IL-4 were significant as complementary explanatory variables of MMP-1 expression. Conclusion The MMP1-1607 SNP was identified as a risk factor for periapical lesions development, possibly due to its association with increased MMP-1 mRNA levels in periapical lesions. The MMP-1 expression is also under the control of the inflammatory milieu elements, being the

  5. Increased plasma dipeptidyl peptidase 4 activities predict new-onset microalbuminuria in association with its proinflammatory effects in Chinese without diabetes: a four-year prospective study.

    PubMed

    Zheng, Tianpeng; Baskota, Attit; Gao, Yun; Tian, Haoming; Yang, Fan

    2015-03-01

    Recent evidence supports a protective role of dipeptidyl peptidase 4 (DPP4) inhibitors in lowering microalbuminuria (MAU) in diabetes but till now few studies have investigated the associations between DPP4 activity and MAU in nondiabetic Chinese individuals. This study tested whether DPP4 activity could predict new-onset MAU in Chinese without diabetes. This was a 4-year prospective study conducted in Sichuan, China. A total of 664 Chinese women and men aged 18-70 years were studied. Circulating DPP4 activity, inflammatory markers and urinary albumin-to-creatinine ratio (ACR) were measured at baseline and 4 years later. The incidence of MAU during follow-up was 33.1 per 1000 patient-years. At baseline, individuals in the highest quartile of DPP4 activity had higher age, body mass index, waist/hip ratio, systolic blood pressure, diastolic blood pressure, fasting insulin, low-density lipoprotein-cholesterol, interleukin-6, high-sensitivity C-reactive protein, urinary albumin-to-creatinine ratio and lower high-density lipoprotein-cholesterol compared with individuals in the lowest quartile. After a 4-year follow-up, 88 individuals developed MAU. In multiple linear regression analysis, baseline DPP4 activity was an independent predictor of an increase in inflammatory markers and ACR over a 4-year period (all P < 0.05). In multivariable-adjusted models, the odds ratio for incident MAU comparing the highest with the lowest quartiles of DPP4 activity was 3.48 (95% CI: 1.50-8.09) after adjustment for confounding risk factors (P < 0.01). The incidence of MAU owing to DPP4 activity increased by 18.59%. DPP4 activity is an important predictor of the onset of inflammation and MAU in Chinese apparently without diabetes. This finding may have important implications for understanding the proinflammatory role of DPP-4 in the pathogenesis of MAU. #TR-CCH-Chi CTR-CCH-00000361. © The Author 2014. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  6. TLR2−/− Mice Display Decreased Severity of Giardiasis via Enhanced Proinflammatory Cytokines Production Dependent on AKT Signal Pathway

    PubMed Central

    Li, Xin; Zhang, Xichen; Gong, Pengtao; Xia, Feifei; Li, Ling; Yang, Zhengtao; Li, Jianhua

    2017-01-01

    Giardia infection is one of the most common causes of waterborne diarrheal disease in a wide array of mammalian hosts, including humans globally. Although numerous studies have indicated that adaptive immune responses are important for Giardia defense, however, whether the host innate immune system such as TLRs recognizes Giardia remains poorly understood. TLR2 plays a crucial role in pathogen recognition, innate immunity activation, and the eventual pathogen elimination. In this study, we investigated the role of TLR2 as a non-protective inflammatory response on controlling the severity of giardiasis. RT-PCR analysis suggested that TLR2 expression was increased in vitro. We demonstrated that Giardia lamblia-induced cytokines expression by the activation of p38 and ERK pathways via TLR2. Interestingly, the expression of IL-12 p40, TNF-α, and IL-6, but not IFN-γ, was enhanced in TLR2-blocked and TLR2−/− mouse macrophages exposed to G. lamblia trophozoites compared with wild-type (WT) mouse macrophages. Further analysis demonstrated that G. lamblia trophozoites reduced cytokines secretion by activating AKT pathway in WT mouse macrophages. Immunohistochemical staining in G. lamblia cysts infected TLR2−/− and WT mice showed that TLR2 was highly expressed in duodenum in infected WT mice. Also, infected TLR2−/− and AKT-blocked mice showed an increased production of IL-12 p40 and IFN-γ compared with infected WT mice at the early stage during infection. Interestingly, infected TLR2−/− and AKT-blocked mice displayed a decreased parasite burden, an increased weight gain rate, and short parasite persistence. Histological morphometry showed shortened villus length, hyperplastic crypt and decreased ratio of villus height/crypt depth in infected WT mice compared with in infected TLR2−/− and AKT-blocked mice. Together, our results suggested that TLR2 deficiency leads to alleviation of giardiasis and reduction of parasite burden through the promotion of

  7. Impaired Striatal Akt Signaling Disrupts Dopamine Homeostasis and Increases Feeding

    PubMed Central

    Davis, Adeola R.; Owens, W. Anthony; Matthies, Heinrich J. G.; Saadat, Sanaz; Kennedy, Jack P.; Vaughan, Roxanne A.; Neve, Rachael L.; Lindsley, Craig W.; Russo, Scott J.; Daws, Lynette C.; Niswender1, Kevin D.; Galli, Aurelio

    2011-01-01

    Background The prevalence of obesity has increased dramatically worldwide. The obesity epidemic begs for novel concepts and therapeutic targets that cohesively address “food-abuse” disorders. We demonstrate a molecular link between impairment of a central kinase (Akt) involved in insulin signaling induced by exposure to a high-fat (HF) diet and dysregulation of higher order circuitry involved in feeding. Dopamine (DA) rich brain structures, such as striatum, provide motivation stimuli for feeding. In these central circuitries, DA dysfunction is posited to contribute to obesity pathogenesis. We identified a mechanistic link between metabolic dysregulation and the maladaptive behaviors that potentiate weight gain. Insulin, a hormone in the periphery, also acts centrally to regulate both homeostatic and reward-based HF feeding. It regulates DA homeostasis, in part, by controlling a key element in DA clearance, the DA transporter (DAT). Upon HF feeding, nigro-striatal neurons rapidly develop insulin signaling deficiencies, causing increased HF calorie intake. Methodology/Principal Findings We show that consumption of fat-rich food impairs striatal activation of the insulin-activated signaling kinase, Akt. HF-induced Akt impairment, in turn, reduces DAT cell surface expression and function, thereby decreasing DA homeostasis and amphetamine (AMPH)-induced DA efflux. In addition, HF-mediated dysregulation of Akt signaling impairs DA-related behaviors such as (AMPH)-induced locomotion and increased caloric intake. We restored nigro-striatal Akt phosphorylation using recombinant viral vector expression technology. We observed a rescue of DAT expression in HF fed rats, which was associated with a return of locomotor responses to AMPH and normalization of HF diet-induced hyperphagia. Conclusions/Significance Acquired disruption of brain insulin action may confer risk for and/or underlie “food-abuse” disorders and the recalcitrance of obesity. This molecular model

  8. Compaction of rolling circle amplification products increases signal integrity and signal-to-noise ratio

    PubMed Central

    Clausson, Carl-Magnus; Arngården, Linda; Ishaq, Omer; Klaesson, Axel; Kühnemund, Malte; Grannas, Karin; Koos, Björn; Qian, Xiaoyan; Ranefall, Petter; Krzywkowski, Tomasz; Brismar, Hjalmar; Nilsson, Mats; Wählby, Carolina; Söderberg, Ola

    2015-01-01

    Rolling circle amplification (RCA) for generation of distinct fluorescent signals in situ relies upon the self-collapsing properties of single-stranded DNA in commonly used RCA-based methods. By introducing a cross-hybridizing DNA oligonucleotide during rolling circle amplification, we demonstrate that the fluorophore-labeled RCA products (RCPs) become smaller. The reduced size of RCPs increases the local concentration of fluorophores and as a result, the signal intensity increases together with the signal-to-noise ratio. Furthermore, we have found that RCPs sometimes tend to disintegrate and may be recorded as several RCPs, a trait that is prevented with our cross-hybridizing DNA oligonucleotide. These effects generated by compaction of RCPs improve accuracy of visual as well as automated in situ analysis for RCA based methods, such as proximity ligation assays (PLA) and padlock probes. PMID:26202090

  9. Age-Associated Increase in BMP Signaling Inhibits Hippocampal Neurogenesis.

    PubMed

    Yousef, Hanadie; Morgenthaler, Adam; Schlesinger, Christina; Bugaj, Lukasz; Conboy, Irina M; Schaffer, David V

    2015-05-01

    Hippocampal neurogenesis, the product of resident neural stem cell proliferation and differentiation, persists into adulthood but decreases with organismal aging, which may contribute to the age-related decline in cognitive function. The mechanisms that underlie this decrease in neurogenesis are not well understood, although evidence in general indicates that extrinsic changes in an aged stem cell niche can contribute to functional decline in old stem cells. Bone morphogenetic protein (BMP) family members are intercellular signaling proteins that regulate stem and progenitor cell quiescence, proliferation, and differentiation in various tissues and are likewise critical regulators of neurogenesis in young adults. Here, we establish that BMP signaling increases significantly in old murine hippocampi and inhibits neural progenitor cell proliferation. Furthermore, direct in vivo attenuation of BMP signaling via genetic and transgenic perturbations in aged mice led to elevated neural stem cell proliferation, and subsequent neurogenesis, in old hippocampi. Such advances in our understanding of mechanisms underlying decreased hippocampal neurogenesis with age may offer targets for the treatment of age-related cognitive decline.

  10. Increased GABAB receptor signaling in a rat model for schizophrenia.

    PubMed

    Selten, Martijn M; Meyer, Francisca; Ba, Wei; Vallès, Astrid; Maas, Dorien A; Negwer, Moritz; Eijsink, Vivian D; van Vugt, Ruben W M; van Hulten, Josephus A; van Bakel, Nick H M; Roosen, Joey; van der Linden, Robert J; Schubert, Dirk; Verheij, Michel M M; Kasri, Nael Nadif; Martens, Gerard J M

    2016-09-30

    Schizophrenia is a complex disorder that affects cognitive function and has been linked, both in patients and animal models, to dysfunction of the GABAergic system. However, the pathophysiological consequences of this dysfunction are not well understood. Here, we examined the GABAergic system in an animal model displaying schizophrenia-relevant features, the apomorphine-susceptible (APO-SUS) rat and its phenotypic counterpart, the apomorphine-unsusceptible (APO-UNSUS) rat at postnatal day 20-22. We found changes in the expression of the GABA-synthesizing enzyme GAD67 specifically in the prelimbic- but not the infralimbic region of the medial prefrontal cortex (mPFC), indicative of reduced inhibitory function in this region in APO-SUS rats. While we did not observe changes in basal synaptic transmission onto LII/III pyramidal cells in the mPFC of APO-SUS compared to APO-UNSUS rats, we report reduced paired-pulse ratios at longer inter-stimulus intervals. The GABAB receptor antagonist CGP 55845 abolished this reduction, indicating that the decreased paired-pulse ratio was caused by increased GABAB signaling. Consistently, we find an increased expression of the GABAB1 receptor subunit in APO-SUS rats. Our data provide physiological evidence for increased presynaptic GABAB signaling in the mPFC of APO-SUS rats, further supporting an important role for the GABAergic system in the pathophysiology of schizophrenia.

  11. Increased GABAB receptor signaling in a rat model for schizophrenia

    PubMed Central

    Selten, Martijn M.; Meyer, Francisca; Ba, Wei; Vallès, Astrid; Maas, Dorien A.; Negwer, Moritz; Eijsink, Vivian D.; van Vugt, Ruben W. M.; van Hulten, Josephus A.; van Bakel, Nick H. M.; Roosen, Joey; van der Linden, Robert J.; Schubert, Dirk; Verheij, Michel M. M.; Kasri, Nael Nadif; Martens, Gerard J. M.

    2016-01-01

    Schizophrenia is a complex disorder that affects cognitive function and has been linked, both in patients and animal models, to dysfunction of the GABAergic system. However, the pathophysiological consequences of this dysfunction are not well understood. Here, we examined the GABAergic system in an animal model displaying schizophrenia-relevant features, the apomorphine-susceptible (APO-SUS) rat and its phenotypic counterpart, the apomorphine-unsusceptible (APO-UNSUS) rat at postnatal day 20–22. We found changes in the expression of the GABA-synthesizing enzyme GAD67 specifically in the prelimbic- but not the infralimbic region of the medial prefrontal cortex (mPFC), indicative of reduced inhibitory function in this region in APO-SUS rats. While we did not observe changes in basal synaptic transmission onto LII/III pyramidal cells in the mPFC of APO-SUS compared to APO-UNSUS rats, we report reduced paired-pulse ratios at longer inter-stimulus intervals. The GABAB receptor antagonist CGP 55845 abolished this reduction, indicating that the decreased paired-pulse ratio was caused by increased GABAB signaling. Consistently, we find an increased expression of the GABAB1 receptor subunit in APO-SUS rats. Our data provide physiological evidence for increased presynaptic GABAB signaling in the mPFC of APO-SUS rats, further supporting an important role for the GABAergic system in the pathophysiology of schizophrenia. PMID:27687783

  12. PMT signal increase using a wavelength shifting paint

    NASA Astrophysics Data System (ADS)

    Allada, K.; Hurlbut, Ch.; Ou, L.; Schmookler, B.; Shahinyan, A.; Wojtsekhowski, B.

    2015-05-01

    We report a 1.65 times increase of the PMT signal and a simple procedure of application of a new wavelength shifting (WLS) paint for PMTs with non-UV-transparent windows. Samples of four different WLS paints, made from hydrocarbon polymers and organic fluors, were tested on a 5-in. PMT (ET 9390KB) using Cherenkov radiation produced in fused silica disks by 106Ru electrons on a 'table-top' setup. The best performing paint was employed on two different types of 5-in. PMTs (ET 9390KB and XP4572B), installed in atmospheric pressure CO2 gas Cherenkov detectors, and tested using GeV electrons.

  13. Both direct and indirect effects account for the pro-inflammatory activity of enteropathogenic mycotoxins on the human intestinal epithelium: Stimulation of interleukin-8 secretion, potentiation of interleukin-1{beta} effect and increase in the transepithelial passage of commensal bacteria

    SciTech Connect

    Maresca, Marc; Yahi, Nouara; Younes-Sakr, Lama; Boyron, Marilyn; Caporiccio, Bertrand; Fantini, Jacques

    2008-04-01

    Mycotoxins are fungal secondary metabolites responsible of food-mediated intoxication in animals and humans. Deoxynivalenol, ochratoxin A and patulin are the best known enteropathogenic mycotoxins able to alter intestinal functions resulting in malnutrition, diarrhea, vomiting and intestinal inflammation in vivo. Although their effects on intestinal barrier and transport activities have been extensively characterized, the mechanisms responsible for their pro-inflammatory effect are still poorly understood. Here we investigated if mycotoxin-induced intestinal inflammation results from a direct and/or indirect pro-inflammatory activity of these mycotoxins on human intestinal epithelial cells, using differentiated Caco-2 cells as model and interleukin 8 (IL-8) as an indicator of intestinal inflammation. Deoxynivalenol was the only mycotoxin able to directly increase IL-8 secretion (10- to 15-fold increase). We also investigated if these mycotoxins could indirectly stimulate IL-8 secretion through: (i) a modulation of the action of pro-inflammatory molecules such as the interleukin-1beta (IL-1{beta}), and/or (ii) an increase in the transepithelial passage of non-invasive commensal Escherichia coli. We found that deoxynivalenol, ochratoxin A and patulin all potentiated the effect of IL-1{beta} on IL-8 secretion (ranging from 35% to 138% increase) and increased the transepithelial passage of commensal bacteria (ranging from 12- to 1544-fold increase). In addition to potentially exacerbate established intestinal inflammation, these mycotoxins may thus participate in the induction of sepsis and intestinal inflammation in vivo. Taken together, our results suggest that the pro-inflammatory activity of enteropathogenic mycotoxins is mediated by both direct and indirect effects.

  14. SphK1 mediates hepatic inflammation in a mouse model of NASH induced by high saturated fat feeding and initiates proinflammatory signaling in hepatocytes.

    PubMed

    Geng, Tuoyu; Sutter, Alton; Harland, Michael D; Law, Brittany A; Ross, Jessica S; Lewin, David; Palanisamy, Arun; Russo, Sarah B; Chavin, Kenneth D; Cowart, L Ashley

    2015-12-01

    Steatohepatitis occurs in up to 20% of patients with fatty liver disease and leads to its primary disease outcomes, including fibrosis, cirrhosis, and increased risk of hepatocellular carcinoma. Mechanisms that mediate this inflammation are of major interest. We previously showed that overload of saturated fatty acids, such as that which occurs with metabolic syndrome, induced sphingosine kinase 1 (SphK1), an enzyme that generates sphingosine-1-phosphate (S1P). While data suggest beneficial roles for S1P in some contexts, we hypothesized that it may promote hepatic inflammation in the context of obesity. Consistent with this, we observed 2-fold elevation of this enzyme in livers from humans with nonalcoholic fatty liver disease and also in mice with high saturated fat feeding, which recapitulated the human disease. Mice exhibited activation of NFκB, elevated cytokine production, and immune cell infiltration. Importantly, SphK1-null mice were protected from these outcomes. Studies in cultured cells demonstrated saturated fatty acid induction of SphK1 message, protein, and activity, and also a requirement of the enzyme for NFκB signaling and increased mRNA encoding TNFα and MCP1. Moreover, saturated fat-induced NFκB signaling and elevation of TNFα and MCP1 mRNA in HepG2 cells was blocked by targeted knockdown of S1P receptor 1, supporting a role for this lipid signaling pathway in inflammation in nonalcoholic fatty liver disease.

  15. Sexual signalling by females: do unmated females increase their signalling effort?

    PubMed Central

    Simmons, Leigh W.

    2015-01-01

    Theory predicts that females should invest least in mate searching when young, but increase their effort with age if they remain unmated. Few studies have examined variation in female sexual signalling. Female Dawson's burrowing bees (Amegilla dawsoni) search for males by signalling their receptivity on emergence, but many leave the emergence site unmated and must attract males at feeding sites. Female bees prevented from mating on emergence had more extreme versions of cuticular hydrocarbon profiles that make them attractive to males, lending empirical evidence of adaptive shifts in female mating effort. PMID:26109613

  16. A mitochondrial superoxide signal triggers increased longevity in Caenorhabditis elegans.

    PubMed

    Yang, Wen; Hekimi, Siegfried

    2010-12-07

    The nuo-6 and isp-1 genes of C. elegans encode, respectively, subunits of complex I and III of the mitochondrial respiratory chain. Partial loss-of-function mutations in these genes decrease electron transport and greatly increase the longevity of C. elegans by a mechanism that is distinct from that induced by reducing their level of expression by RNAi. Electron transport is a major source of the superoxide anion (O(⋅) (-)), which in turn generates several types of toxic reactive oxygen species (ROS), and aging is accompanied by increased oxidative stress, which is an imbalance between the generation and detoxification of ROS. These observations have suggested that the longevity of such mitochondrial mutants might result from a reduction in ROS generation, which would be consistent with the mitochondrial oxidative stress theory of aging. It is difficult to measure ROS directly in living animals, and this has held back progress in determining their function in aging. Here we have adapted a technique of flow cytometry to directly measure ROS levels in isolated mitochondria to show that the generation of superoxide is elevated in the nuo-6 and isp-1 mitochondrial mutants, although overall ROS levels are not, and oxidative stress is low. Furthermore, we show that this elevation is necessary and sufficient to increase longevity, as it is abolished by the antioxidants NAC and vitamin C, and phenocopied by mild treatment with the prooxidant paraquat. Furthermore, the absence of effect of NAC and the additivity of the effect of paraquat on a variety of long- and short-lived mutants suggest that the pathway triggered by mitochondrial superoxide is distinct from previously studied mechanisms, including insulin signaling, dietary restriction, ubiquinone deficiency, the hypoxic response, and hormesis. These findings are not consistent with the mitochondrial oxidative stress theory of aging. Instead they show that increased superoxide generation acts as a signal in young

  17. Cholesterol Depletion Alters Cardiomyocyte Subcellular Signaling and Increases Contractility

    PubMed Central

    McIntosh, Victoria J.; Abou Samra, Abdul B.; Mohammad, Ramzi M.; Lasley, Robert D.

    2016-01-01

    Membrane cholesterol levels play an important factor in regulating cell function. Sarcolemmal cholesterol is concentrated in lipid rafts and caveolae, which are flask-shaped invaginations of the plasma membrane. The scaffolding protein caveolin permits the enrichment of cholesterol in caveolae, and caveolin interactions with numerous proteins regulate their function. The purpose of this study was to determine whether acute reductions in cardiomyocyte cholesterol levels alter subcellular protein kinase activation, intracellular Ca2+ and contractility. Methods: Ventricular myocytes, isolated from adult Sprague Dawley rats, were treated with the cholesterol reducing agent methyl-β-cyclodextrin (MβCD, 5 mM, 1 hr, room temperature). Total cellular cholesterol levels, caveolin-3 localization, subcellular, ERK and p38 mitogen activated protein kinase (MAPK) signaling, contractility, and [Ca2+]i were assessed. Results: Treatment with MβCD reduced cholesterol levels by ~45 and shifted caveolin-3 from cytoskeleton and triton-insoluble fractions to the triton-soluble fraction, and increased ERK isoform phosphorylation in cytoskeletal, cytosolic, triton-soluble and triton-insoluble membrane fractions without altering their subcellular distributions. In contrast the primary effect of MβCD was on p38 subcellular distribution of p38α with little effect on p38 phosphorylation. Cholesterol depletion increased cardiomyocyte twitch amplitude and the rates of shortening and relaxation in conjunction with increased diastolic and systolic [Ca2+]i. Conclusions: These results indicate that acute reductions in membrane cholesterol levels differentially modulate basal cardiomyocyte subcellular MAPK signaling, as well as increasing [Ca2+]i and contractility. PMID:27441649

  18. Increased entropy of signal transduction in the cancer metastasis phenotype

    PubMed Central

    2010-01-01

    Background The statistical study of biological networks has led to important novel biological insights, such as the presence of hubs and hierarchical modularity. There is also a growing interest in studying the statistical properties of networks in the context of cancer genomics. However, relatively little is known as to what network features differ between the cancer and normal cell physiologies, or between different cancer cell phenotypes. Results Based on the observation that frequent genomic alterations underlie a more aggressive cancer phenotype, we asked if such an effect could be detectable as an increase in the randomness of local gene expression patterns. Using a breast cancer gene expression data set and a model network of protein interactions we derive constrained weighted networks defined by a stochastic information flux matrix reflecting expression correlations between interacting proteins. Based on this stochastic matrix we propose and compute an entropy measure that quantifies the degree of randomness in the local pattern of information flux around single genes. By comparing the local entropies in the non-metastatic versus metastatic breast cancer networks, we here show that breast cancers that metastasize are characterised by a small yet significant increase in the degree of randomness of local expression patterns. We validate this result in three additional breast cancer expression data sets and demonstrate that local entropy better characterises the metastatic phenotype than other non-entropy based measures. We show that increases in entropy can be used to identify genes and signalling pathways implicated in breast cancer metastasis and provide examples of de-novo discoveries of gene modules with known roles in apoptosis, immune-mediated tumour suppression, cell-cycle and tumour invasion. Importantly, we also identify a novel gene module within the insulin growth factor signalling pathway, alteration of which may predispose the tumour to

  19. Salt-inducible kinase 3 deficiency exacerbates lipopolysaccharide-induced endotoxin shock accompanied by increased levels of pro-inflammatory molecules in mice

    PubMed Central

    Sanosaka, Masato; Fujimoto, Minoru; Ohkawara, Tomoharu; Nagatake, Takahiro; Itoh, Yumi; Kagawa, Mai; Kumagai, Ayako; Fuchino, Hiroyuki; Kunisawa, Jun; Naka, Tetsuji; Takemori, Hiroshi

    2015-01-01

    Macrophages play important roles in the innate immune system during infection and systemic inflammation. When bacterial lipopolysaccharide (LPS) binds to Toll-like receptor 4 on macrophages, several signalling cascades co-operatively up-regulate gene expression of inflammatory molecules. The present study aimed to examine whether salt-inducible kinase [SIK, a member of the AMP-activated protein kinase (AMPK) family] could contribute to the regulation of immune signal not only in cultured macrophages, but also in vivo. LPS up-regulated SIK3 expression in murine RAW264.7 macrophages and exogenously over-expressed SIK3 negatively regulated the expression of inflammatory molecules [interleukin-6 (IL-6), nitric oxide (NO) and IL-12p40] in RAW264.7 macrophages. Conversely, these inflammatory molecule levels were up-regulated in SIK3-deficient thioglycollate-elicited peritoneal macrophages (TEPM), despite no impairment of the classical signalling cascades. Forced expression of SIK3 in SIK3-deficient TEPM suppressed the levels of the above-mentioned inflammatory molecules. LPS injection (10 mg/kg) led to the death of all SIK3-knockout (KO) mice within 48 hr after treatment, whereas only one mouse died in the SIK1-KO (n = 8), SIK2-KO (n = 9) and wild-type (n = 8 or 9) groups. In addition, SIK3-KO bone marrow transplantation increased LPS sensitivity of the recipient wild-type mice, which was accompanied by an increased level of circulating IL-6. These results suggest that SIK3 is a unique negative regulator that suppresses inflammatory molecule gene expression in LPS-stimulated macrophages. PMID:25619259

  20. Single automated donor plateletpheresis increases the plasma level of proinflammatory cytokine tumor necrosis factor-alpha which does not associate with endothelial release markers von Willebrand factor and fibronectin.

    PubMed

    Karadoğan, I; Ozdoğan, M; Undar, L

    2000-12-01

    The effect of plateletpheresis on endothelium, which has strong effects on blood coagulation, fibrinolysis and platelet function, is not known. Activation of leukocytes and subsequent generation of proinflammatory cytokines during the extracorporeal circulation may activate the endothelium. To test this hypothesis we measured plasma levels of tumor necrosis factor (TNF)-alpha as a prototype of the proinflammatory cytokines, and von Willebrand factor (vWF) and fibronectin as endothelial release/damage markers before and after a single plateletpheresis procedure on an intermittent-flow machine Haemonetics MCS 3p in 17 healthy donors. We found a significant increase in median plasma level of TNF-alpha following plateletpheresis (3.5 vs 26.5 pg/ml, P=0.02). Such increases in vWF and fibronectin were not observed. The increase in plasma TNF-alpha indicates that a single plateletpheresis procedure causes leukocyte activation which does not seemingly impair endothelial cell function. The relation of plateletpheresis-induced proinflammatory cytokine release to some adverse effects observed in both donors and recipients, and the effect of repeated plateletpheresis on endothelium deserve further studies.

  1. MET signalling in primary colon epithelial cells leads to increased transformation irrespective of aberrant Wnt signalling

    PubMed Central

    Boon, E M J; Kovarikova, M; Derksen, P W B; van der Neut, R

    2005-01-01

    It has been shown that in hereditary and most sporadic colon tumours, components of the Wnt pathway are mutated. The Wnt target MET has been implicated in the development of colon cancer. Here, we show that overexpression of wild-type or a constitutively activated form of MET in colon epithelial cells leads to increased transformation irrespective of Wnt signalling. Fetal human colon epithelial cells without aberrant Wnt signalling were transfected with wild-type or mutated MET constructs. Expression of these constructs leads to increased phosphorylation of MET and its downstream targets PKB and MAPK. Upon stimulation with HGF, the expression of E-cadherin is downregulated in wild-type MET-transfected cells, whereas cells expressing mutated MET show low E-cadherin levels independent of stimulation with ligand. This implies a higher migratory propensity of these cells. Furthermore, fetal human colon epithelial cells expressing the mutated form of MET have colony-forming capacity in soft agar, while cells expressing wild-type MET show an intermediate phenotype. Subcutaneous injection of mutated MET-transfected cells in nude mice leads to the formation of tumours within 12 days in all mice injected. At this time point, mock-transfected cells do not form tumours, while wild-type MET-transfected cells form subcutaneous tumours in one out of five mice. We thus show that MET signalling can lead to increased transformation of colon epithelial cells independent of Wnt signalling and in this way could play an essential role in the onset and progression of colorectal cancer. PMID:15785735

  2. MET signalling in primary colon epithelial cells leads to increased transformation irrespective of aberrant Wnt signalling.

    PubMed

    Boon, E M J; Kovarikova, M; Derksen, P W B; van der Neut, R

    2005-03-28

    It has been shown that in hereditary and most sporadic colon tumours, components of the Wnt pathway are mutated. The Wnt target MET has been implicated in the development of colon cancer. Here, we show that overexpression of wild-type or a constitutively activated form of MET in colon epithelial cells leads to increased transformation irrespective of Wnt signalling. Fetal human colon epithelial cells without aberrant Wnt signalling were transfected with wild-type or mutated MET constructs. Expression of these constructs leads to increased phosphorylation of MET and its downstream targets PKB and MAPK. Upon stimulation with HGF, the expression of E-cadherin is downregulated in wild-type MET-transfected cells, whereas cells expressing mutated MET show low E-cadherin levels independent of stimulation with ligand. This implies a higher migratory propensity of these cells. Furthermore, fetal human colon epithelial cells expressing the mutated form of MET have colony-forming capacity in soft agar, while cells expressing wild-type MET show an intermediate phenotype. Subcutaneous injection of mutated MET-transfected cells in nude mice leads to the formation of tumours within 12 days in all mice injected. At this time point, mock-transfected cells do not form tumours, while wild-type MET-transfected cells form subcutaneous tumours in one out of five mice. We thus show that MET signalling can lead to increased transformation of colon epithelial cells independent of Wnt signalling and in this way could play an essential role in the onset and progression of colorectal cancer.

  3. A novel mouse model of Campylobacter jejuni gastroenteritis reveals key pro-inflammatory and tissue protective roles for Toll-like receptor signaling during infection.

    PubMed

    Stahl, Martin; Ries, Jenna; Vermeulen, Jenny; Yang, Hong; Sham, Ho Pan; Crowley, Shauna M; Badayeva, Yuliya; Turvey, Stuart E; Gaynor, Erin C; Li, Xiaoxia; Vallance, Bruce A

    2014-07-01

    Campylobacter jejuni is a major source of foodborne illness in the developed world, and a common cause of clinical gastroenteritis. Exactly how C. jejuni colonizes its host's intestines and causes disease is poorly understood. Although it causes severe diarrhea and gastroenteritis in humans, C. jejuni typically dwells as a commensal microbe within the intestines of most animals, including birds, where its colonization is asymptomatic. Pretreatment of C57BL/6 mice with the antibiotic vancomycin facilitated intestinal C. jejuni colonization, albeit with minimal pathology. In contrast, vancomycin pretreatment of mice deficient in SIGIRR (Sigirr(-/-)), a negative regulator of MyD88-dependent signaling led to heavy and widespread C. jejuni colonization, accompanied by severe gastroenteritis involving strongly elevated transcription of Th1/Th17 cytokines. C. jejuni heavily colonized the cecal and colonic crypts of Sigirr(-/-) mice, adhering to, as well as invading intestinal epithelial cells. This infectivity was dependent on established C. jejuni pathogenicity factors, capsular polysaccharides (kpsM) and motility/flagella (flaA). We also explored the basis for the inflammatory response elicited by C. jejuni in Sigirr(-/-) mice, focusing on the roles played by Toll-like receptors (TLR) 2 and 4, as these innate receptors were strongly stimulated by C. jejuni. Despite heavy colonization, Tlr4(-/-)/Sigirr(-/-) mice were largely unresponsive to infection by C. jejuni, whereas Tlr2(-/-)/Sigirr(-/-) mice developed exaggerated inflammation and pathology. This indicates that TLR4 signaling underlies the majority of the enteritis seen in this model, whereas TLR2 signaling had a protective role, acting to promote mucosal integrity. Furthermore, we found that loss of the C. jejuni capsule led to increased TLR4 activation and exaggerated inflammation and gastroenteritis. Together, these results validate the use of Sigirr(-/-) mice as an exciting and relevant animal model for

  4. A Novel Mouse Model of Campylobacter jejuni Gastroenteritis Reveals Key Pro-inflammatory and Tissue Protective Roles for Toll-like Receptor Signaling during Infection

    PubMed Central

    Stahl, Martin; Yang, Hong; Sham, Ho Pan; Crowley, Shauna M.; Badayeva, Yuliya; Turvey, Stuart E.; Gaynor, Erin C.; Li, Xiaoxia; Vallance, Bruce A.

    2014-01-01

    Campylobacter jejuni is a major source of foodborne illness in the developed world, and a common cause of clinical gastroenteritis. Exactly how C. jejuni colonizes its host's intestines and causes disease is poorly understood. Although it causes severe diarrhea and gastroenteritis in humans, C. jejuni typically dwells as a commensal microbe within the intestines of most animals, including birds, where its colonization is asymptomatic. Pretreatment of C57BL/6 mice with the antibiotic vancomycin facilitated intestinal C. jejuni colonization, albeit with minimal pathology. In contrast, vancomycin pretreatment of mice deficient in SIGIRR (Sigirr−/−), a negative regulator of MyD88-dependent signaling led to heavy and widespread C. jejuni colonization, accompanied by severe gastroenteritis involving strongly elevated transcription of Th1/Th17 cytokines. C. jejuni heavily colonized the cecal and colonic crypts of Sigirr−/− mice, adhering to, as well as invading intestinal epithelial cells. This infectivity was dependent on established C. jejuni pathogenicity factors, capsular polysaccharides (kpsM) and motility/flagella (flaA). We also explored the basis for the inflammatory response elicited by C. jejuni in Sigirr−/− mice, focusing on the roles played by Toll-like receptors (TLR) 2 and 4, as these innate receptors were strongly stimulated by C. jejuni. Despite heavy colonization, Tlr4−/−/Sigirr−/− mice were largely unresponsive to infection by C. jejuni, whereas Tlr2−/−/Sigirr−/− mice developed exaggerated inflammation and pathology. This indicates that TLR4 signaling underlies the majority of the enteritis seen in this model, whereas TLR2 signaling had a protective role, acting to promote mucosal integrity. Furthermore, we found that loss of the C. jejuni capsule led to increased TLR4 activation and exaggerated inflammation and gastroenteritis. Together, these results validate the use of Sigirr−/− mice as an exciting and relevant animal

  5. Neu1 sialidase and matrix metalloproteinase-9 cross-talk regulates nucleic acid-induced endosomal TOLL-like receptor-7 and -9 activation, cellular signaling and pro-inflammatory responses.

    PubMed

    Abdulkhalek, Samar; Szewczuk, Myron R

    2013-11-01

    The precise mechanism(s) by which intracellular TOLL-like receptors (TLRs) become activated by their ligands remains unclear. Here, we report a molecular organizational G-protein coupled receptor (GPCR) signaling platform to potentiate a novel mammalian neuraminidase-1 (Neu1) and matrix metalloproteinase-9 (MMP-9) cross-talk in alliance with neuromedin B GPCR, all of which form a tripartite complex with TLR-7 and -9. siRNA silencing Neu1, MMP-9 and neuromedin-B GPCR in RAW-blue macrophage cells significantly reduced TLR7 imiquimod- and TLR9 ODN1826-induced NF-κB (NF-κB-pSer(536)) activity. Tamiflu, specific MMP-9 inhibitor, neuromedin B receptor specific antagonist BIM23127, and the selective inhibitor of whole heterotrimeric G-protein complex BIM-46174 significantly block nucleic acid-induced TLR-7 and -9 MyD88 recruitment, NF-κB activation and proinflammatory TNFα and MCP-1 cytokine responses. For the first time, Neu1 clearly plays a central role in mediating nucleic acid-induced intracellular TLR activation, and the interactions involving NMBR-MMP9-Neu1 cross-talk constitute a novel intracellular TLR signaling platform that is essential for NF-κB activation and pro-inflammatory responses.

  6. PGF2α modulates the output of chemokines and pro-inflammatory cytokines in myometrial cells from term pregnant women through divergent signaling pathways

    PubMed Central

    Xu, Chen; Liu, Weina; You, Xingji; Leimert, Kelycia; Popowycz, Krystyn; Fang, Xin; Wood, Stephen L.; Slater, Donna M.; Sun, Qianqian; Gu, Hang; Olson, David M.; Ni, Xin

    2015-01-01

    Prostaglandin F2α (PGF2α) plays a critical role in the initiation and process of parturition. Since human labor has been described as an inflammatory event, we investigated the role of PGF2α in the inflammatory process using cultured human uterine smooth muscle cells (HUSMCs) isolated from term pregnant women as a model. Using a multiplex assay, HUSMCs treated with PGF2α changed their output of a number of cytokines and chemokines, with a distinct response pattern that differed between HUSMCs isolated from the upper and lower segment region of the uterus. Confirmatory enzyme-linked immunosorbent assays (ELISAs) showed that PGF2α stimulated increased output of interleukin (IL) 1β, IL6, IL8 (CXCL8) and monocyte chemotactic protein-1 (MCP1, also known as chemokine (c-c motif) ligand 2, CCL2) by HUSMCs isolated from both upper and lower uterine segments. In contrast, PGF2α inhibited tumor necrosis factor α (TNFα) release by HUMSCs from the lower uterine segment while the output of TNFα was undetectable in the upper segment. Small interfering (si) RNA mediated knockdown of the PGF2α receptor prevented the changes in cytokine and chemokine output by the HUSMCs. Since the PGF2α receptor (PTGFR) couples via the Gq protein and subsequently activates the phospholipase C (PLC) and protein kinase C (PKC) signaling pathways, we examined the role of these pathways in PGF2α modulation of the cytokines. Inhibition of PLC and PKC reversed the effects of PGF2α. PGF2α activated multiple signaling pathways including extracellular signal-regulated kinases (ERK) 1/2, phosphatidylinositol-4,5-bisphosphate 3-kinase (PI3K), P38, calcineurin/nuclear factor of activated T-cells (NFAT) and NF-κB signaling. Inhibition of ERK reversed PGF2α-induced IL1β, IL6 and CCL2 output, while inhibition of PI3K blocked the effect of PGF2α on IL6, CXCL8 and CCL2 output and inhibition of NF-κB reversed PGF2α-induced IL1β and CCL2 output. NFAT was involved in PGF2α modulation of CCL2

  7. Dystrophic muscle improvement in zebrafish via increased heme oxygenase signaling

    PubMed Central

    Kawahara, Genri; Gasperini, Molly J.; Myers, Jennifer A.; Widrick, Jeffrey J.; Eran, Alal; Serafini, Peter R.; Alexander, Matthew S.; Pletcher, Mathew T.; Morris, Carl A.; Kunkel, Louis M.

    2014-01-01

    Duchenne muscular dystrophy (DMD) is caused by a lack of the dystrophin protein and has no effective treatment at present. Zebrafish provide a powerful in vivo tool for high-throughput therapeutic drug screening for the improvement of muscle phenotypes caused by dystrophin deficiency. Using the dystrophin-deficient zebrafish, sapje, we have screened a total of 2640 compounds with known modes of action from three drug libraries to identify modulators of the disease progression. Six compounds that target heme oxygenase signaling were found to rescue the abnormal muscle phenotype in sapje and sapje-like, while upregulating the inducible heme oxygenase 1 (Hmox1) at the protein level. Direct Hmox1 overexpression by injection of zebrafish Hmox1 mRNA into fertilized eggs was found to be sufficient for a dystrophin-independent restoration of normal muscle via an upregulation of cGMP levels. In addition, treatment of mdx5cv mice with the PDE5 inhibitor, sildenafil, which was one of the six drugs impacting the Hmox1 pathway in zebrafish, significantly increased the expression of Hmox1 protein, thus making Hmox1 a novel target for the improvement of dystrophic symptoms. These results demonstrate the translational relevance of our zebrafish model to mammalian models and support the use of zebrafish to screen for new drugs to treat human DMD. The discovery of a small molecule and a specific therapeutic pathway that might mitigate DMD disease progression could lead to significant clinical implications. PMID:24234649

  8. Stress increases aversive prediction error signal in the ventral striatum.

    PubMed

    Robinson, Oliver J; Overstreet, Cassie; Charney, Danielle R; Vytal, Katherine; Grillon, Christian

    2013-03-05

    From job interviews to the heat of battle, it is evident that people think and learn differently when stressed. In fact, learning under stress may have long-term consequences; stress facilitates aversive conditioning and associations learned during extreme stress may result in debilitating emotional responses in posttraumatic stress disorder. The mechanisms underpinning such stress-related associations, however, are unknown. Computational neuroscience has successfully characterized several mechanisms critical for associative learning under normative conditions. One such mechanism, the detection of a mismatch between expected and observed outcomes within the ventral striatum (i.e., "prediction errors"), is thought to be a critical precursor to the formation of new stimulus-outcome associations. An untested possibility, therefore, is that stress may affect learning via modulation of this mechanism. Here we combine a translational model of stress with a cognitive neuroimaging paradigm to demonstrate that stress significantly increases ventral striatum aversive (but not appetitive) prediction error signal. This provides a unique account of the propensity to form threat-related associations under stress with direct implications for our understanding of both normal stress and stress-related disorders.

  9. Increased Brain Signal Variability Accompanies Lower Behavioral Variability in Development

    PubMed Central

    McIntosh, Anthony Randal; Kovacevic, Natasa; Itier, Roxane J.

    2008-01-01

    As the brain matures, its responses become optimized. Behavioral measures show this through improved accuracy and decreased trial-to-trial variability. The question remains whether the supporting brain dynamics show a similar decrease in variability. We examined the relation between variability in single trial evoked electrical activity of the brain (measured with EEG) and performance of a face memory task in children (8–15 y) and young adults (20–33 y). Behaviorally, children showed slower, more variable response times (RT), and less accurate recognition than adults. However, brain signal variability increased with age, and showed strong negative correlations with intrasubject RT variability and positive correlations with accuracy. Thus, maturation appears to lead to a brain with greater functional variability, which is indicative of enhanced neural complexity. This variability may reflect a broader repertoire of metastable brain states and more fluid transitions among them that enable optimum responses. Our results suggest that the moment-to-moment variability in brain activity may be a critical index of the cognitive capacity of the brain. PMID:18604265

  10. Pro-inflammatory cytokine-driven PI3K/Akt/Sp1 signalling and H2S production facilitates the pathogenesis of severe acute pancreatitis.

    PubMed

    Liu, Ying; Liao, Ribin; Qiang, Zhanrong; Zhang, Cheng

    2017-04-30

    Severe acute pancreatitis (SAP) is a disease usually associated with systemic organ dysfunction or pancreatic necrosis. Most patients with SAP suffer from defective intestinal motility in the early phase of the disease. Additionally, SAP-induced inflammation produces hydrogen sulphide (H2S) that impairs the gastrointestinal (GI) system. However, the exact mechanism of H2S in the regulation of SAP is yet to be elucidated. In the present paper, we used a rat model of SAP to evaluate the role of H2S on intestinal motility by counting the number of bowel movements and investigating the effect of H2S on inflammation. We treated colonic muscle cells (CMCs) with SAP plasma, tumour necrosis factor-α (TNF-α) or interleukin-6 (IL-6) and measured the expressions of H2S-producing enzymes cystathionine-γ-lyase (CSE), cystathionine-β-synthase (CBS) and Sp1 and PI3K/Akt by using quantitative PCR, Western blotting and immunohistochemical detection. We used the PI3K inhibitor LY294002 and the siRNA si-Sp1 to suppress the activity of the PI3K/Akt/Sp1 signalling pathway. We found that, in the SAP rat model, H2S facilitated an inhibitory effect on intestinal motility and enhanced the inflammatory response caused by SAP (P<0.05). The expressions of CSE and CBS in CMCs were significantly increased after treatment with TNF-α or IL-6 (P<0.05). Blocking the PI3K/Akt/Sp1 pathway remarkably inhibited the synthesis of CSE and CBS. Our data demonstrated that H2S plays a vital role in the pathogenesis of SAP and that SAP is modulated by inflammation driven by the PI3K/Akt/Sp1 signalling pathway. © 2017 The Author(s).

  11. Inhibition of G-Protein βγ Signaling Decreases Levels of Messenger RNAs Encoding Proinflammatory Cytokines in T Cell Receptor-Stimulated CD4+ T Helper Cells

    PubMed Central

    Hynes, Thomas R.; Yost, Evan A.; Hartle, Cassandra M.; Ott, Braden J.

    2015-01-01

    Background: Inhibition of G-protein βγ (Gβγ) signaling was found previously to enhance T cell receptor (TCR)-stimulated increases in interleukin 2 (IL-2) mRNA in CD4+ T helper cells, suggesting that Gβγ might be a useful drug target for treating autoimmune diseases, as low dose IL-2 therapy can suppress autoimmune responses. Because IL-2 may counteract autoimmunity in part by shifting CD4+ T helper cells away from the Type 1 T helper cell (TH1) and TH17 subtypes towards the TH2 subtype, the purpose of this study was to determine if blocking Gβγ signaling affected the balance of TH1, TH17, and TH2 cytokine mRNAs produced by CD4+ T helper cells. Methods: Gallein, a small molecule inhibitor of Gβγ, and siRNA-mediated silencing of the G-protein β1 subunit (Gβ1) were used to test the effect of blocking Gβγ on mRNA levels of cytokines in primary human TCR-stimulated CD4+ T helper cells. Results: Gallein and Gβ1 siRNA decreased interferon-γ (IFN-γ) and IL-17A mRNA levels in TCR-stimulated CD4+ T cells grown under TH1-promoting conditions. Inhibiting Gβγ also decreased mRNA levels of STAT4, which plays a positive role in TH1 differentiation and IL-17A production. Moreover, mRNA levels of the STAT4-regulated TH1-associated proteins, IL-18 receptor β chain (IL-18Rβ), mitogen-activated protein kinase kinase kinase 8 (MAP3K8), lymphocyte activation gene 3 (LAG-3), natural killer cell group 7 sequence (NKG7), and oncostatin M (OSM) were also decreased upon Gβγ inhibition. Gallein also increased IL-4, IL-5, IL-9, and IL-13 mRNA levels in TCR-stimulated memory CD4+ T cells grown in TH2-promoting conditions. Conclusions: Inhibiting Gβγ to produce these shifts in cytokine mRNA production might be beneficial for patients with autoimmune diseases such as rheumatoid arthritis (RA), Crohn’s disease (CD), psoriasis, multiple sclerosis (MS), and Hashimoto’s thyroiditis (HT), in which both IFN-γ and IL-17A are elevated. PMID:27095999

  12. Effect of a negative energy balance induced by feed restriction on pro-inflammatory and endoplasmic reticulum stress signalling pathways in the liver and skeletal muscle of lactating sows.

    PubMed

    Gessner, Denise K; Gröne, Birthe; Rosenbaum, Susann; Most, Erika; Hillen, Sonja; Becker, Sabrina; Erhardt, Georg; Reiner, Gerald; Ringseis, Robert; Eder, Klaus

    2015-01-01

    High-producing sows develop typical signs of an inflammatory condition and endoplasmic reticulum (ER) stress in the liver during lactation. At present, it is unknown whether a negative energy balance (NEB) is causative for this. Therefore, an experiment with lactating sows, which were either restricted in their feed intake to 82% of their energy requirement (Group FR) or were fed to meet their energy requirement (Control), was performed and the effect on ER stress-induced unfolded protein response (UPR), nuclear factor kappa B (NF-κB), nuclear factor E2-related factor 2 (Nrf2) and NOD-like receptor P3 (NLRP3) inflammasome signalling in the liver was evaluated. Relative mRNA concentrations of several genes involved in ER stress-induced UPR, NF-κB and NLRP3 inflammasome signalling were reduced in the liver of Group FR compared to the Control group. Plasma concentrations of haptoglobin and C-reactive protein were 13% and 37%, respectively, lower in Group FR than in the Control group, but these differences were not significant. In conclusion, feed restriction in lactating sows inhibits pro-inflammatory and ER stress signalling pathways in the liver, which suggests that not the NEB per se is causative for inflammation and ER stress induction in the liver of lactating sows. Rather it is likely that ER stress during lactation is the consequence of the presence of potent pro-inflammatory and ER stress-inducing stimuli, such as cytokines, reactive oxygen species and microbial components, which enter the circulation as a result of infectious diseases that frequently occur in sows after farrowing.

  13. Downregulation of microRNA-107 in intestinal CD11c(+) myeloid cells in response to microbiota and proinflammatory cytokines increases IL-23p19 expression.

    PubMed

    Xue, Xiaochang; Cao, Anthony T; Cao, Xiaocang; Yao, Suxia; Carlsen, Eric D; Soong, Lynn; Liu, Chang-Gong; Liu, Xiuping; Liu, Zhanju; Duck, L Wayne; Elson, Charles O; Cong, Yingzi

    2014-03-01

    Commensal flora plays an important role in the development of the mucosal immune system and in maintaining intestinal homeostasis. However, the mechanisms involved in regulation of host-microbiota interaction are still not completely understood. In this study, we examined how microbiota and intestinal inflammatory conditions regulate host microRNA expression and observed lower microRNA-107 (miR-107) expression in the inflamed intestines of colitic mice, compared with that in normal control mice. miR-107 was predominantly reduced in epithelial cells and CD11c(+) myeloid cells including dendritic cells and macrophages in the inflamed intestines. We demonstrate that IL-6, IFN-γ, and TNF-α downregulated, whereas TGF-β promoted, miR-107 expression. In addition, miR-107 expression was higher in the intestines of germ-free mice than in mice housed under specific pathogen-free conditions, and the presence of microbiota downregulated miR-107 expression in DCs and macrophages in a MyD88- and NF-κB-dependent manner. We determined that the ectopic expression of miR-107 specifically repressed the expression of IL-23p19, a key molecule in innate immune responses to commensal bacteria. We concluded that regulation of miR-107 by intestinal microbiota and proinflammatory cytokine serve as an important pathway for maintaining intestinal homeostasis. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  14. A heat-stable cytotoxic factor produced by Achromobacter xylosoxidans isolated from Brazilian patients with CF is associated with in vitro increased proinflammatory cytokines.

    PubMed

    Mantovani, Rebeca P; Levy, Carlos E; Yano, Tomomasa

    2012-07-01

    Recently, Achromobacter xylosoxidans has been related to chronic lung diseases in patients suffering from cystic fibrosis (CF), but its involvement has not been elucidated. Some virulence properties of A. xylosoxidans isolated from Brazilian patients with CF were revealed in this work. This study examined the production of a cytotoxic factor of A. xylosoxidans capable of stimulating the secretion of inflammatory cytokines (IL-6 and IL-8) from lung mucoepidermoid carcinoma cells (NCI-H292). The cytokines were measured using enzyme-linked immunosorbent (ELISA) assays. To investigate whether the cytotoxic factors may be endotoxins, they were treated with polymyxin B. The culture supernatants of all A. xylosoxidans produced a heat stable, active cytotoxin in NCI-H292 cells capable of leading to intracellular vacuoles and subsequent cell contact loss, chromatin condensation, a picnotic nucleus and cell death. There was a higher concentration of proinflammatory cytokines in the NCI-H292 cells after 24 h of incubation, with the fraction greater than 50 kDa from the culture supernatant. The cytotoxin activity remained even after treatment with polymyxin B, which suggested that the release of IL-6 and IL-8 was not stimulated by lipopolysaccharide (LPS). The cytotoxic factor produced by A. xylosoxidans may represent an important virulence factor, which when associated with CF chronic lung inflammation, may cause tissue damage and decline of lung function. Copyright © 2012 European Cystic Fibrosis Society. Published by Elsevier B.V. All rights reserved.

  15. Nuclear factor-κB is a common upstream signal for growth differentiation factor-5 expression in brown adipocytes exposed to pro-inflammatory cytokines and palmitate

    SciTech Connect

    Hinoi, Eiichi; Iezaki, Takashi; Ozaki, Kakeru; Yoneda, Yukio

    2014-10-03

    Highlights: • GDF5 expression is up-regulated by IL-1β, TNF-α and palmitate in brown pre-adipocytes. • NF-κB stimulates promoter activity and expression of GDF5 in brown pre-adipocytes. • Recruitment of NF-κB to the GDF5 promoter is facilitated in BAT from ob/ob mice. • An NF-κB inhibitor prevents upregulation of GDF5 expression in brown pre-adipocytes. - Abstract: We have previously demonstrated that genetic and acquired obesity similarly led to drastic upregulation in brown adipose tissue (BAT), rather than white adipose tissue, of expression of both mRNA and corresponding protein for the bone morphogenic protein/growth differentiation factor (GDF) member GDF5 capable of promoting brown adipogenesis. In this study, we evaluated expression profiles of GDF5 in cultured murine brown pre-adipocytes exposed to pro-inflammatory cytokines and free fatty acids (FFAs), which are all shown to play a role in the pathogenesis of obesity. Both interleukin-1β (IL-1β) and tumor necrosis factor-α (TNF-α) were effective in up-regulating GDF5 expression in a concentration-dependent manner, while similar upregulation was seen in cells exposed to the saturated FFA palmitate, but not to the unsaturated FFA oleate. In silico analysis revealed existence of the putative nuclear factor-κB (NF-κB) binding site in the 5′-flanking region of mouse GDF5, whereas introduction of NF-κB subunits drastically facilitated both promoter activity and expression of GDF5 in brown pre-adipocytes. Chromatin immunoprecipitation analysis confirmed significant facilitation of the recruitment of NF-κB to the GDF5 promoter in lysed extracts of BAT from leptin-deficient ob/ob obese mice. Upregulation o GDF5 expression was invariably inhibited by an NF-κB inhibitor in cultured brown pre-adipocytes exposed to IL-1β, TNF-α and palmitate. These results suggest that obesity leads to upregulation of GDF5 expression responsible for the promotion of brown adipogenesis through a mechanism

  16. Exposure to Carbon Ions Triggers Proinflammatory Signals and Changes in Homeostasis and Epidermal Tissue Organization to a Similar Extent as Photons

    PubMed Central

    Simoniello, Palma; Wiedemann, Julia; Zink, Joana; Thoennes, Eva; Stange, Maike; Layer, Paul G.; Kovacs, Maximilian; Podda, Maurizio; Durante, Marco; Fournier, Claudia

    2016-01-01

    The increasing application of charged particles in radiotherapy requires a deeper understanding of early and late side effects occurring in skin, which is exposed in all radiation treatments. We measured cellular and molecular changes related to the early inflammatory response of human skin irradiated with carbon ions, in particular cell death induction and changes in differentiation and proliferation of epidermal cells during the first days after exposure. Model systems for human skin from healthy donors of different complexity, i.e., keratinocytes, coculture of skin cells, 3D skin equivalents, and skin explants, were used to investigate the alterations induced by carbon ions (spread-out Bragg peak, dose-averaged LET 100 keV/μm) in comparison to X-ray and UV-B exposure. After exposure to ionizing radiation, in none of the model systems, apoptosis/necrosis was observed. Carbon ions triggered inflammatory signaling and accelerated differentiation of keratinocytes to a similar extent as X-rays at the same doses. High doses of carbon ions were more effective than X-rays in reducing proliferation and inducing abnormal differentiation. In contrast, changes identified following low-dose exposure (≤0.5 Gy) were induced more effectively after X-ray exposure, i.e., enhanced proliferation and change in the polarity of basal cells. PMID:26779439

  17. IL-17A Signaling in Colonic Epithelial Cells Inhibits Pro-Inflammatory Cytokine Production by Enhancing the Activity of ERK and PI3K

    PubMed Central

    Xiao, Yan; Zhou, Tingting; Guo, Yueling; Wang, Renxi; Zhao, Zhi; Xiao, He; Hou, Chunmei; Ma, Lingyun; Lin, Yanhua; Lang, Xiaoling; Feng, Jiannan; Chen, Guojiang; Shen, Beifen; Han, Gencheng; Li, Yan

    2014-01-01

    Our previous data suggested that IL-17A contributes to the inhibition of Th1 cell function in the gut. However, the underlying mechanisms remain unclear. Here we demonstrate that IL-17A signaling in colonic epithelial cells (CECs) increases TNF-α-induced PI3K-AKT and ERK phosphorylation and inhibits TNF-α induced expression of IL-12P35 and of a Th1 cell chemokine, CXCL11 at mRNA level. In a co-culture system using HT-29 cells and PBMCs, IL-17A inhibited TNF-ãinduced IL-12P35 expression by HT-29 cells and led to decreased expression of IFN-γ and T-bet by PBMCs. Finally, adoptive transfer of CECs from mice with Crohn's Disease (CD) led to an enhanced Th1 cell response and exacerbated colitis in CD mouse recipients. The pathogenic effect of CECs derived from CD mice was reversed by co-administration of recombinant IL-17A. Our data demonstrate a new IL-17A-mediated regulatory mechanism in CD. A better understanding of this pathway might shed new light on the pathogenesis of CD. PMID:24586980

  18. Influenza A Viruses Replicate Productively in Mouse Mastocytoma Cells (P815) and Trigger Pro-inflammatory Cytokine and Chemokine Production through TLR3 Signaling Pathway

    PubMed Central

    Meng, Di; Huo, Caiyun; Wang, Ming; Xiao, Jin; Liu, Bo; Wei, Tangting; Dong, Hong; Zhang, Guozhong; Hu, Yanxin; Sun, Lunquan

    2017-01-01

    The influenza A viruses (IAVs) cause acute respiratory infection in both humans and animals. As a member of the initial lines of host defense system, the role of mast cells during IAV infection has been poorly understood. Here, we characterized for the first time that both avian-like (α-2, 3-linked) and human-like (α-2, 6- linked) sialic acid (SA) receptors were expressed by the mouse mastocytoma cell line (P815). The P815 cells did support the productive replication of H1N1 (A/WSN/33), H5N1 (A/chicken/ Henan/1/04) and H7N2 (A/chicken/Hebei/2/02) in vitro while the in vivo infection of H5N1 in mast cells was confirmed by the specific staining of nasal mucosa and lung tissue from mice. All the three viruses triggered the infected P815 cells to produce pro-inflammatory cytokines and chemokines including IL-6, IFN-γ, TNF-α, CCL-2, CCL-5, and IP-10, but not the antiviral type I interferon. It was further confirmed that TLR3 pathway was involved in P815 cell response to IAV-infection. Our findings highlight the remarkable tropism and infectivity of IAV to P815 cells, indicating that mast cells may be unneglectable player in the development of IAV infection. PMID:28127293

  19. The anti-malarial artemisinin inhibits pro-inflammatory cytokines via the NF-κB canonical signaling pathway in PMA-induced THP-1 monocytes.

    PubMed

    Wang, Yue; Huang, Zhouqing; Wang, Liansheng; Meng, Shu; Fan, Yuqi; Chen, Ting; Cao, Jiatian; Jiang, Rujia; Wang, Changqian

    2011-02-01

    Several kinds of sesquiterpene lactones have been proven to inhibit NF-κB and to retard atherosclerosis by reducing lesion size and changing plaque composition. The anti-malarial artemisinin (Art) is a pure sesquiterpene lactone extracted from the Chinese herb Artemisia annua (qinghao, sweet wormwood). In the present study, we demonstrate that artemisinin inhibits the secretion and the mRNA levels of tumor necrosis factor (TNF)-α, interleukin (IL)-1ß, and IL-6 in a dose-dependent manner in phorbol 12-myristate 13-acetate (PMA)-induced THP-1 human monocytes. We also found that the NF-κB specific inhibitor, Bay 11-7082, inhibited the expression of these pro-inflammatory cytokines, suggesting that the NF-κB pathway may be involved in the decreased cytokine release. At all time-points (1-6 h), artemisinin impeded the phosphorylation of IKKα/ß, the phosphorylation and degradation of IκBα and the nuclear translocation of the NF-κB p65 subunit. Additionally, artemisinin inhibited the translocation of the NF-κB p65 subunit as demonstrated by confocal laser scanning microscopic analysis and by NF-κB binding assays. Our data indicate that artemisinin exerts an anti-inflammatory effect on PMA-induced THP-1 monocytes, suggesting the potential role of artemisinin in preventing the inflammatory progression of atherosclerosis.

  20. Sickle red cells as danger signals on proinflammatory gene expression, leukotriene B4 and interleukin-1 beta production in peripheral blood mononuclear cell.

    PubMed

    Pitanga, Thassila N; Oliveira, Ricardo R; Zanette, Dalila L; Guarda, Caroline C; Santiago, Rayra P; Santana, Sanzio S; Nascimento, Valma M L; Lima, Jonilson B; Carvalho, Graziele Q; Maffili, Vitor V; Carvalho, Magda O S; Alcântara, Luiz C J; Borges, Valéria M; Goncalves, Marilda S

    2016-07-01

    This study tested the hypothesis that sickle red blood cell (SS-RBC) induce Toll-like receptors (TLR) and Nod-like receptor family, pyrin domain containing 3 (NLRP3)- inflammasome expression in peripheral blood mononuclear cells (PBMC). TLR and NLRP3 inflammasome could contribute to the maintenance of the inflammatory status in sickle cell anemia (SCA) patients, since SS-RBC act as danger signals activating these pathways. In this study, first, we evaluated TLR (2, 4, 5 and 9), NLRP3, Caspase-1, interleukin (IL)-1β and IL-18 expression in PBMC freshly isolated from SCA patients (SS-PBMC) in comparison with PBMC from healthy individuals (AA-PBMC). In the second moment, we investigated whether SS-RBC could interfere with the expression of these molecules in PBMC from healthy donor, in the absence or presence of hydroxyurea (HU) in vitro. TLRs and NLRP3 inflammasome expression were investigated by qPCR. IL-1β, Leukotriene-B4 (LTB4) and nitrite production were measured in PBMC (from healthy donor) culture supernatants. TLR2, TLR4, TLR5, NLRP3 and IL-1β were highly expressed in SS-PBMC when compared to AA-PBMC. Additionally, SS-RBC induced TLR9, NLRP3, Caspase-1, IL-1β and IL-18 expression and induced IL-1β, LTB4 and nitrite production in PBMC cultures. HU did not prevent TLR and NLRP3 inflammasome expression, but increased TLR2 and IL-18 expression and reduced nitrite production. In conclusion, our data suggest that TLR and inflammasome complexes may be key inducers of inflammation in SCA patients, probably through SS-RBC; also, HU does not prevent NLRP3 inflammasome- and TLR-dependent inflammation, indicating the need to develop new therapeutic strategies to SCA patients that act with different mechanisms of those observed for HU.

  1. The Angiotensin-(1-7)/Mas Axis Counteracts Angiotensin II-Dependent and -Independent Pro-inflammatory Signaling in Human Vascular Smooth Muscle Cells.

    PubMed

    Villalobos, Laura A; San Hipólito-Luengo, Álvaro; Ramos-González, Mariella; Cercas, Elena; Vallejo, Susana; Romero, Alejandra; Romacho, Tania; Carraro, Raffaele; Sánchez-Ferrer, Carlos F; Peiró, Concepción

    2016-01-01

    Background and Aims: Targeting inflammation is nowadays considered as a challenging pharmacological strategy to prevent or delay the development of vascular diseases. Angiotensin-(1-7) is a member of the renin-angiotensin system (RAS) that binds Mas receptors and has gained growing attention in the last years as a regulator of vascular homeostasis. Here, we explored the capacity of Ang-(1-7) to counteract human aortic smooth muscle cell (HASMC) inflammation triggered by RAS-dependent and -independent stimuli, such as Ang II or interleukin (IL)-1β. Methods and Results: In cultured HASMC, the expression of inducible nitric oxide synthase (iNOS) and the release of nitric oxide were stimulated by both Ang II and IL-1β, as determined by Western blot and indirect immunofluorescence or the Griess method, respectively. iNOS induction was inhibited by Ang-(1-7) in a concentration-dependent manner. This effect was equally blocked by two different Mas receptor antagonists, A779 and D-Pro(7)-Ang-(1-7), suggesting the participation of a unique Mas receptor subtype. Using pharmacological inhibitors, the induction of iNOS was proven to rely on the consecutive upstream activation of NADPH oxidase and nuclear factor (NF)-κB. Indeed, Ang-(1-7) markedly inhibited the activation of the NADPH oxidase and subsequently of NF-κB, as determined by lucigenin-derived chemiluminescence and electromobility shift assay, respectively. Conclusion: Ang-(1-7) can act as a counter-regulator of the inflammation of vascular smooth muscle cells triggered by Ang II, but also by other stimuli beyond the RAS. Activating or mimicking the Ang-(1-7)/Mas axis may represent a pharmacological opportunity to attenuate the pro-inflammatory environment that promotes and sustains the development of vascular diseases.

  2. The Angiotensin-(1-7)/Mas Axis Counteracts Angiotensin II-Dependent and -Independent Pro-inflammatory Signaling in Human Vascular Smooth Muscle Cells

    PubMed Central

    Villalobos, Laura A.; San Hipólito-Luengo, Álvaro; Ramos-González, Mariella; Cercas, Elena; Vallejo, Susana; Romero, Alejandra; Romacho, Tania; Carraro, Raffaele; Sánchez-Ferrer, Carlos F.; Peiró, Concepción

    2016-01-01

    Background and Aims: Targeting inflammation is nowadays considered as a challenging pharmacological strategy to prevent or delay the development of vascular diseases. Angiotensin-(1-7) is a member of the renin-angiotensin system (RAS) that binds Mas receptors and has gained growing attention in the last years as a regulator of vascular homeostasis. Here, we explored the capacity of Ang-(1-7) to counteract human aortic smooth muscle cell (HASMC) inflammation triggered by RAS-dependent and -independent stimuli, such as Ang II or interleukin (IL)-1β. Methods and Results: In cultured HASMC, the expression of inducible nitric oxide synthase (iNOS) and the release of nitric oxide were stimulated by both Ang II and IL-1β, as determined by Western blot and indirect immunofluorescence or the Griess method, respectively. iNOS induction was inhibited by Ang-(1-7) in a concentration-dependent manner. This effect was equally blocked by two different Mas receptor antagonists, A779 and D-Pro7-Ang-(1-7), suggesting the participation of a unique Mas receptor subtype. Using pharmacological inhibitors, the induction of iNOS was proven to rely on the consecutive upstream activation of NADPH oxidase and nuclear factor (NF)-κB. Indeed, Ang-(1-7) markedly inhibited the activation of the NADPH oxidase and subsequently of NF-κB, as determined by lucigenin-derived chemiluminescence and electromobility shift assay, respectively. Conclusion: Ang-(1-7) can act as a counter-regulator of the inflammation of vascular smooth muscle cells triggered by Ang II, but also by other stimuli beyond the RAS. Activating or mimicking the Ang-(1-7)/Mas axis may represent a pharmacological opportunity to attenuate the pro-inflammatory environment that promotes and sustains the development of vascular diseases. PMID:28018220

  3. Secondhand Smoke-Prevalent Polycyclic Aromatic Hydrocarbon Binary Mixture-Induced Specific Mitogenic and Pro-inflammatory Cell Signaling Events in Lung Epithelial Cells.

    PubMed

    Osgood, Ross S; Upham, Brad L; Bushel, Pierre R; Velmurugan, Kalpana; Xiong, Ka-Na; Bauer, Alison K

    2017-05-01

    Low molecular weight polycyclic aromatic hydrocarbons (LMW PAHs; < 206.3 g/mol) are prevalent and ubiquitous environmental contaminants, presenting a human health concern, and have not been as thoroughly studied as the high MW PAHs. LMW PAHs exert their pulmonary effects, in part, through P38-dependent and -independent mechanisms involving cell-cell communication and the production of pro-inflammatory mediators known to contribute to lung disease. Specifically, we determined the effects of two representative LMW PAHs, 1-methylanthracene (1-MeA) and fluoranthene (Flthn), individually and as a binary PAH mixture on the dysregulation of gap junctional intercellular communication (GJIC) and connexin 43 (Cx43), activation of mitogen activated protein kinases (MAPK), and induction of inflammatory mediators in a mouse non-tumorigenic alveolar type II cell line (C10). Both 1-MeA, Flthn, and the binary PAH mixture of 1-MeA and Flthn dysregulated GJIC in a dose and time-dependent manner, reduced Cx43 protein, and activated the following MAPKs: P38, ERK1/2, and JNK. Inhibition of P38 MAPK prevented PAH-induced dysregulation of GJIC, whereas inhibiting ERK and JNK did not prevent these PAHs from dysregulating GJIC indicating a P38-dependent mechanism. A toxicogenomic approach revealed significant P38-dependent and -independent pathways involved in inflammation, steroid synthesis, metabolism, and oxidative responses. Genes in these pathways were significantly altered by the binary PAH mixture when compared with 1-MeA and Flthn alone suggesting interactive effects. Exposure to the binary PAH mixture induced the production and release of cytokines and metalloproteinases from the C10 cells. Our findings with a binary mixture of PAHs suggest that combinations of LMW PAHs may elicit synergistic or additive inflammatory responses which warrant further investigation and confirmation. © The Author 2017. Published by Oxford University Press on behalf of the Society of Toxicology

  4. Resveratrol modulates phorbol ester-induced pro-inflammatory signal transduction pathways in mouse skin in vivo: NF-kappaB and AP-1 as prime targets.

    PubMed

    Kundu, Joydeb Kumar; Shin, Young Kee; Surh, Young-Joon

    2006-11-30

    Functional abnormalities of intracellular signaling network cause the disruption in homeostasis maintained by critical cellular components, thereby accelerating premalignant and malignant transformation. Multiple lines of evidence suggest that an elevated expression of cyclooxygenase-2 (COX-2) is causally linked to tumorigenesis. The exposure to oxidative/pro-inflammatory stimuli turns on signaling arrays mediated by diverse classes of kinases and transcription factors, which may lead to aberrant expression of COX-2. We have attempted to unravel the signal transduction pathways involved in elevated COX-2 expression in mouse skin stimulated with a prototype tumor promoter 12-O-tetradecanoylphorbol-13-acetate (TPA) and its modulation by resveratrol, a phytoalexin known to exert potential chemopreventive effects. Our study revealed that topical application of TPA induced COX-2 expression in mouse skin via activation of nuclear factor-kappaB (NF-kappaB), which is regulated by upstream IkappaB kinase (IKK) or differentially by mitogen-activated protein (MAP) kinases. Besides NF-kappaB, the p38 MAP kinase-mediated activation of activator protein-1 (AP-1) has also been attributed to TPA-induced COX-2 expression in mouse skin. Among the MAP kinases, extracellular signal-regulated protein kinase (ERK) and p38 MAP kinase have been shown to regulate TPA-induced NF-kappaB activation, while p38 MAP kinase and c-Jun-N-terminal kinase are preferentially involved in TPA-induced activation of AP-1 in mouse skin in vivo. This commentary focuses on resveratrol modulation of intracellular signaling pathways involved in aberrant COX-2 expression in TPA-stimulated mouse skin to delineate molecular mechanisms underlying antitumor promoting effects of resveratrol.

  5. Increased mRNA expression of selected pro-inflammatory factors in inflamed bovine endometrium in vivo as well as in endometrial epithelial cells exposed to Bacillus pumilus in vitro.

    PubMed

    Gärtner, Martina A; Peter, Sarah; Jung, Markus; Drillich, Marc; Einspanier, Ralf; Gabler, Christoph

    2016-06-01

    Endometrial epithelium plays a crucial role in the first immune response to invading bacteria by producing cytokines and chemokines. The aim of this study was to investigate the first inflammatory response of the endometrium in vivo and in vitro. Gene expression of several pro-inflammatory factors and Toll-like receptors (TLR2, -4, -6) was determined in endometrial cytobrush samples obtained from healthy cows and cows with clinical or subclinical endometritis. Endometrial epithelial cells were co-cultured with an isolated autochthonous uterine bacterial strain Bacillus pumilus. Total RNA was extracted from in vivo and in vitro samples and subjected to real-time reverse transcription polymerase chain reaction. CXC ligands (CXCL) 1/2 and CXC chemokine receptor (CXCR) 2 mRNA expression was higher in cows with subclinical endometritis and CXCL3 mRNA expression was higher in cows with clinical endometritis compared with healthy cows. B. pumilus induced cell death of epithelial cells within 24h of co-culturing. The presence of B. pumilus resulted in significantly higher mRNA expression of interleukin 1α (IL1A), IL6, IL8, CXCL1-3 and prostaglandin-endoperoxide synthase 2 in co-cultured cells compared with untreated controls. The maximum increase was mainly detected after 2h. These results support the hypothesis that bacterial infection of endometrial cells might induce prompt synthesis of pro-inflammatory cytokines resulting in a local inflammatory reaction.

  6. Pediatric patients with inflammatory bowel disease exhibit increased serum levels of proinflammatory cytokines and chemokines, but decreased circulating levels of macrophage inhibitory protein-1β, interleukin-2 and interleukin-17

    PubMed Central

    KLEINER, GIULIO; ZANIN, VALENTINA; MONASTA, LORENZO; CROVELLA, SERGIO; CARUSO, LORENZO; MILANI, DANIELA; MARCUZZI, ANNALISA

    2015-01-01

    Inflammatory bowel disease (IBD) is a chronic and progressive inflammatory condition of the gastrointestinal tract. Although the causative events that lead to the onset of IBD are yet to be fully elucidated, deregulation of immune and inflammatory mechanisms are hypothesized to significantly contribute to this disorder. Since the onset of IBD is often during infancy, in the present study, the serum values of a large panel of cytokines and chemokines in pediatric patients (<18 years; n=26) were compared with age-matched controls (n=37). While elevations in the serum level of several proinflammatory and immune regulating cytokines were confirmed, such as interleukin (IL)-1β, IL-5, IL-7, interferon (IFN)-γ-inducible protein-10, IL-16, cutaneous T-cell-attracting chemokine, leukemia inhibitory factor, monokine induced by γ-IFN, IFN-α2 and IFN-γ, notably decreased levels of IL-2, IL-17 and macrophage inhibitory protein-1β were also observed. Therefore, while a number of proinflammatory cytokines exhibit increased levels in IBD patients, pediatric IBD patients may also exhibit certain aspects of a reduced immunological response. PMID:26136934

  7. Pediatric patients with inflammatory bowel disease exhibit increased serum levels of proinflammatory cytokines and chemokines, but decreased circulating levels of macrophage inhibitory protein-1β, interleukin-2 and interleukin-17.

    PubMed

    Kleiner, Giulio; Zanin, Valentina; Monasta, Lorenzo; Crovella, Sergio; Caruso, Lorenzo; Milani, Daniela; Marcuzzi, Annalisa

    2015-06-01

    Inflammatory bowel disease (IBD) is a chronic and progressive inflammatory condition of the gastrointestinal tract. Although the causative events that lead to the onset of IBD are yet to be fully elucidated, deregulation of immune and inflammatory mechanisms are hypothesized to significantly contribute to this disorder. Since the onset of IBD is often during infancy, in the present study, the serum values of a large panel of cytokines and chemokines in pediatric patients (<18 years; n=26) were compared with age-matched controls (n=37). While elevations in the serum level of several proinflammatory and immune regulating cytokines were confirmed, such as interleukin (IL)-1β, IL-5, IL-7, interferon (IFN)-γ-inducible protein-10, IL-16, cutaneous T-cell-attracting chemokine, leukemia inhibitory factor, monokine induced by γ-IFN, IFN-α2 and IFN-γ, notably decreased levels of IL-2, IL-17 and macrophage inhibitory protein-1β were also observed. Therefore, while a number of proinflammatory cytokines exhibit increased levels in IBD patients, pediatric IBD patients may also exhibit certain aspects of a reduced immunological response.

  8. N(6)-(2-Hydroxyethyl)adenosine in the Medicinal Mushroom Cordyceps cicadae Attenuates Lipopolysaccharide-Stimulated Pro-inflammatory Responses by Suppressing TLR4-Mediated NF-κB Signaling Pathways.

    PubMed

    Lu, Meng-Ying; Chen, Chin-Chu; Lee, Li-Ya; Lin, Ting-Wei; Kuo, Chia-Feng

    2015-10-23

    Natural products play an important role in promoting health with relation to the prevention of chronic inflammation. N(6)-(2-Hydroxyethyl)adenosine (HEA), a physiologically active compound in the medicinal mushroom Cordyceps cicadae, has been identified as a Ca(2+) antagonist and shown to control circulation and possess sedative activity in pharmacological tests. The fruiting body of C. cicadae has been widely applied in Chinese medicine. However, neither the anti-inflammatory activities of HEA nor the fruiting bodies of C. cicadae have been carefully examined. In this study, we first cultured the fruiting bodies of C. cicadae and then investigated the anti-inflammatory activities of water and methanol extracts of wild and artificially cultured C. cicadae fruiting bodies. Next, we determined the amount of three bioactive compounds, adenosine, cordycepin, and HEA, in the extracts and evaluated their synergistic anti-inflammatory effects. Moreover, the possible mechanism involved in anti-inflammatory action of HEA isolated from C. cicadae was investigated. The results indicate that cordycepin is more potent than adenosine and HEA in suppressing the lipopolysaccharide (LPS)-stimulated release of pro-inflammatory cytokines by RAW 264.7 macrophages; however, no synergistic effect was observed with these three compounds. HEA attenuated the LPS-induced pro-inflammatory responses by suppressing the toll-like receptor (TLR)4-mediated nuclear factor-κB (NF-κB) signaling pathway. This result will support the use of HEA as an anti-inflammatory agent and C. cicadae fruiting bodies as an anti-inflammatory mushroom.

  9. Dysfunctional nitric oxide signalling increases risk of myocardial infarction.

    PubMed

    Erdmann, Jeanette; Stark, Klaus; Esslinger, Ulrike B; Rumpf, Philipp Moritz; Koesling, Doris; de Wit, Cor; Kaiser, Frank J; Braunholz, Diana; Medack, Anja; Fischer, Marcus; Zimmermann, Martina E; Tennstedt, Stephanie; Graf, Elisabeth; Eck, Sebastian; Aherrahrou, Zouhair; Nahrstaedt, Janja; Willenborg, Christina; Bruse, Petra; Brænne, Ingrid; Nöthen, Markus M; Hofmann, Per; Braund, Peter S; Mergia, Evanthia; Reinhard, Wibke; Burgdorf, Christof; Schreiber, Stefan; Balmforth, Anthony J; Hall, Alistair S; Bertram, Lars; Steinhagen-Thiessen, Elisabeth; Li, Shu-Chen; März, Winfried; Reilly, Muredach; Kathiresan, Sekar; McPherson, Ruth; Walter, Ulrich; Ott, Jurg; Samani, Nilesh J; Strom, Tim M; Meitinger, Thomas; Hengstenberg, Christian; Schunkert, Heribert

    2013-12-19

    Myocardial infarction, a leading cause of death in the Western world, usually occurs when the fibrous cap overlying an atherosclerotic plaque in a coronary artery ruptures. The resulting exposure of blood to the atherosclerotic material then triggers thrombus formation, which occludes the artery. The importance of genetic predisposition to coronary artery disease and myocardial infarction is best documented by the predictive value of a positive family history. Next-generation sequencing in families with several affected individuals has revolutionized mutation identification. Here we report the segregation of two private, heterozygous mutations in two functionally related genes, GUCY1A3 (p.Leu163Phefs*24) and CCT7 (p.Ser525Leu), in an extended myocardial infarction family. GUCY1A3 encodes the α1 subunit of soluble guanylyl cyclase (α1-sGC), and CCT7 encodes CCTη, a member of the tailless complex polypeptide 1 ring complex, which, among other functions, stabilizes soluble guanylyl cyclase. After stimulation with nitric oxide, soluble guanylyl cyclase generates cGMP, which induces vasodilation and inhibits platelet activation. We demonstrate in vitro that mutations in both GUCY1A3 and CCT7 severely reduce α1-sGC as well as β1-sGC protein content, and impair soluble guanylyl cyclase activity. Moreover, platelets from digenic mutation carriers contained less soluble guanylyl cyclase protein and consequently displayed reduced nitric-oxide-induced cGMP formation. Mice deficient in α1-sGC protein displayed accelerated thrombus formation in the microcirculation after local trauma. Starting with a severely affected family, we have identified a link between impaired soluble-guanylyl-cyclase-dependent nitric oxide signalling and myocardial infarction risk, possibly through accelerated thrombus formation. Reversing this defect may provide a new therapeutic target for reducing the risk of myocardial infarction.

  10. Neurotensin-induced Proinflammatory Signaling in Human Colonocytes Is Regulated by β-Arrestins and Endothelin-converting Enzyme-1-dependent Endocytosis and Resensitization of Neurotensin Receptor 1*

    PubMed Central

    Law, Ivy Ka Man; Murphy, Jane E.; Bakirtzi, Kyriaki; Bunnett, Nigel W.; Pothoulakis, Charalabos

    2012-01-01

    The neuropeptide/hormone neurotensin (NT) mediates intestinal inflammation and cell proliferation by binding of its high affinity receptor, neurotensin receptor-1 (NTR1). NT stimulates IL-8 expression in NCM460 human colonic epithelial cells by both MAP kinase- and NF-κB-dependent pathways. Although the mechanism of NTR1 endocytosis has been studied, the relationship between NTR1 intracellular trafficking and inflammatory signaling remains to be elucidated. In the present study, we show that in NCM460 cells exposed to NT, β-arrestin-1 (βARR1), and β-arrestin-2 (βARR2) translocate to early endosomes together with NTR1. Endothelin-converting enzyme-1 (ECE-1) degrades NT in acidic conditions, and its activity is crucial for NTR1 recycling. Pretreatment of NCM460 cells with the ECE-1 inhibitor SM19712 or gene silencing of βARR1 or βARR2 inhibits NT-stimulated ERK1/2 and JNK phosphorylation, NF-κB p65 nuclear translocation and phosphorylation, and IL-8 secretion. Furthermore, NT-induced cell proliferation, but not IL-8 transcription, is attenuated by the JNK inhibitor, JNK(AII). Thus, NTR1 internalization and recycling in human colonic epithelial cells involves βARRs and ECE-1, respectively. Our results also indicate that βARRs and ECE-1-dependent recycling regulate MAP kinase and NF-κB signaling as well as cell proliferation in human colonocytes in response to NT. PMID:22416137

  11. High levels of acetoacetate and glucose increase expression of cytokines in bovine hepatocytes, through activation of the NF-κB signalling pathway.

    PubMed

    Li, Yu; Ding, Hongyan; Wang, Xichun; Liu, Lei; Huang, Dan; Zhang, Renhe; Guo, Lihui; Wang, Zhe; Li, Xiaobing; Liu, Guowen; Wu, Jinjie; Li, Xinwei

    2016-02-01

    Elevated levels of blood interleukin-1β (IL-1β), interleukin-6 (IL-6) and tumour necrosis factor-α (TNF-α) increase insulin resistance and result in inflammation. It is not clear whether elevated blood level of acetoacetate (ACAC) and decreased blood level of glucose, which are the predominant characteristics of clinical biochemistry in ketotic dairy cows, increase proinflammatory cytokines and subsequent inflammation. The objective of this study was to test the hypothesis that ACAC and glucose activate the NF-κB signalling pathway to regulate cytokines expression in bovine hepatocytes. Bovine hepatocytes were cultured with ACAC (0-4.8 mm) and glucose (0-5.55 mm) with or without NF-κB inhibitor PDTC for 24 h. The secretion and mRNA levels of cytokines were determined by enzyme-linked immunosorbent assay (ELISA) and real-time fluorescence quantitative polymerase chain reaction (qRT-PCR). The NF-κB signalling pathway activation was evaluated by western blotting. Results showed that the secretion and expression of IL-1β, IL-6 and TNF-α increased in an ACAC dose-dependent manner. Additionally, there was an increase in the secretion and mRNA expression of these three cytokines in glucose treatment group, which increased significantly when the glucose concentrations exceed 3.33 mm. Furthermore, both ACAC and glucose upregulated NF-κB p65 protein expression and IκBα phosphorylation levels. However, these effects were reduced by PDTC. These results demonstrate that elevated levels of ACAC and glucose increase the synthesis and expression of proinflammatory factors by activating NF-κB signalling pathway in hepatocytes, which may contribute to inflammation injury in ketotic dairy cows.

  12. TNF-TNFR2/p75 Signaling Inhibits Early and Increases Delayed Nontargeted Effects in Bone Marrow-derived Endothelial Progenitor Cells*

    PubMed Central

    Sasi, Sharath P.; Song, Jin; Park, Daniel; Enderling, Heiko; McDonald, J. Tyson; Gee, Hannah; Garrity, Brittany; Shtifman, Alexander; Yan, Xinhua; Walsh, Kenneth; Natarajan, Mohan; Kishore, Raj; Goukassian, David A.

    2014-01-01

    TNF-α, a pro-inflammatory cytokine, is highly expressed after being irradiated (IR) and is implicated in mediating radiobiological bystander responses (RBRs). Little is known about specific TNF receptors in regulating TNF-induced RBR in bone marrow-derived endothelial progenitor cells (BM-EPCs). Full body γ-IR WT BM-EPCs showed a biphasic response: slow decay of p-H2AX foci during the initial 24 h and increase between 24 h and 7 days post-IR, indicating a significant RBR in BM-EPCs in vivo. Individual TNF receptor (TNFR) signaling in RBR was evaluated in BM-EPCs from WT, TNFR1/p55KO, and TNFR2/p75KO mice, in vitro. Compared with WT, early RBR (1–5 h) were inhibited in p55KO and p75KO EPCs, whereas delayed RBR (3–5 days) were amplified in p55KO EPCs, suggesting a possible role for TNFR2/p75 signaling in delayed RBR. Neutralizing TNF in γ-IR conditioned media (CM) of WT and p55KO BM-EPCs largely abolished RBR in both cell types. ELISA protein profiling of WT and p55KO EPC γ-IR-CM over 5 days showed significant increases in several pro-inflammatory cytokines, including TNF-α, IL-1α (Interleukin-1 alpha), RANTES (regulated on activation, normal T cell expressed and secreted), and MCP-1. In vitro treatments with murine recombinant (rm) TNF-α and rmIL-1α, but not rmMCP-1 or rmRANTES, increased the formation of p-H2AX foci in nonirradiated p55KO EPCs. We conclude that TNF-TNFR2 signaling may induce RBR in naïve BM-EPCs and that blocking TNF-TNFR2 signaling may prevent delayed RBR in BM-EPCs, conceivably, in bone marrow milieu in general. PMID:24711449

  13. Cannabis use: signal of increasing risk of serious cardiovascular disorders.

    PubMed

    Jouanjus, Emilie; Lapeyre-Mestre, Maryse; Micallef, Joelle

    2014-04-23

    Cannabis is known to be associated with neuropsychiatric problems, but less is known about complications affecting other specified body systems. We report and analyze 35 recent remarkable cardiovascular complications following cannabis use. In France, serious cases of abuse and dependence in response to the use of psychoactive substances must be reported to the national system of the French Addictovigilance Network. We identified all spontaneous reports of cardiovascular complications related to cannabis use collected by the French Addictovigilance Network from 2006 to 2010. We described the clinical characteristics of these cases and their evolution: 1.8% of all cannabis-related reports (35/1979) were cardiovascular complications, with patients being mostly men (85.7%) and of an average age of 34.3 years. There were 22 cardiac complications (20 acute coronary syndromes), 10 peripheral complications (lower limb or juvenile arteriopathies and Buerger-like diseases), and 3 cerebral complications (acute cerebral angiopathy, transient cortical blindness, and spasm of cerebral artery). In 9 cases, the event led to patient death. Increased reporting of cardiovascular complications related to cannabis and their extreme seriousness (with a death rate of 25.6%) indicate cannabis as a possible risk factor for cardiovascular disease in young adults, in line with previous findings. Given that cannabis is perceived to be harmless by the general public and that legalization of its use is debated, data concerning its danger must be widely disseminated. Practitioners should be aware that cannabis may be a potential triggering factor for cardiovascular complications in young people.

  14. CaM Kinase II mediates maladaptive post-infarct remodeling and pro-inflammatory chemoattractant signaling but not acute myocardial ischemia/reperfusion injury

    PubMed Central

    Weinreuter, Martin; Kreusser, Michael M; Beckendorf, Jan; Schreiter, Friederike C; Leuschner, Florian; Lehmann, Lorenz H; Hofmann, Kai P; Rostosky, Julia S; Diemert, Nathalie; Xu, Chang; Volz, Hans Christian; Jungmann, Andreas; Nickel, Alexander; Sticht, Carsten; Gretz, Norbert; Maack, Christoph; Schneider, Michael D; Gröne, Hermann-Josef; Müller, Oliver J; Katus, Hugo A; Backs, Johannes

    2014-01-01

    CaMKII was suggested to mediate ischemic myocardial injury and adverse cardiac remodeling. Here, we investigated the roles of different CaMKII isoforms and splice variants in ischemia/reperfusion (I/R) injury by the use of new genetic CaMKII mouse models. Although CaMKIIδC was upregulated 1 day after I/R injury, cardiac damage 1 day after I/R was neither affected in CaMKIIδ-deficient mice, CaMKIIδ-deficient mice in which the splice variants CaMKIIδB and C were re-expressed, nor in cardiomyocyte-specific CaMKIIδ/γ double knockout mice (DKO). In contrast, 5 weeks after I/R, DKO mice were protected against extensive scar formation and cardiac dysfunction, which was associated with reduced leukocyte infiltration and attenuated expression of members of the chemokine (C-C motif) ligand family, in particular CCL3 (macrophage inflammatory protein-1α, MIP-1α). Intriguingly, CaMKII was sufficient and required to induce CCL3 expression in isolated cardiomyocytes, indicating a cardiomyocyte autonomous effect. We propose that CaMKII-dependent chemoattractant signaling explains the effects on post-I/R remodeling. Taken together, we demonstrate that CaMKII is not critically involved in acute I/R-induced damage but in the process of post-infarct remodeling and inflammatory processes. PMID:25193973

  15. CaM Kinase II mediates maladaptive post-infarct remodeling and pro-inflammatory chemoattractant signaling but not acute myocardial ischemia/reperfusion injury.

    PubMed

    Weinreuter, Martin; Kreusser, Michael M; Beckendorf, Jan; Schreiter, Friederike C; Leuschner, Florian; Lehmann, Lorenz H; Hofmann, Kai P; Rostosky, Julia S; Diemert, Nathalie; Xu, Chang; Volz, Hans Christian; Jungmann, Andreas; Nickel, Alexander; Sticht, Carsten; Gretz, Norbert; Maack, Christoph; Schneider, Michael D; Gröne, Hermann-Josef; Müller, Oliver J; Katus, Hugo A; Backs, Johannes

    2014-10-01

    CaMKII was suggested to mediate ischemic myocardial injury and adverse cardiac remodeling. Here, we investigated the roles of different CaMKII isoforms and splice variants in ischemia/reperfusion (I/R) injury by the use of new genetic CaMKII mouse models. Although CaMKIIδC was upregulated 1 day after I/R injury, cardiac damage 1 day after I/R was neither affected in CaMKIIδ-deficient mice, CaMKIIδ-deficient mice in which the splice variants CaMKIIδB and C were re-expressed, nor in cardiomyocyte-specific CaMKIIδ/γ double knockout mice (DKO). In contrast, 5 weeks after I/R, DKO mice were protected against extensive scar formation and cardiac dysfunction, which was associated with reduced leukocyte infiltration and attenuated expression of members of the chemokine (C-C motif) ligand family, in particular CCL3 (macrophage inflammatory protein-1α, MIP-1α). Intriguingly, CaMKII was sufficient and required to induce CCL3 expression in isolated cardiomyocytes, indicating a cardiomyocyte autonomous effect. We propose that CaMKII-dependent chemoattractant signaling explains the effects on post-I/R remodeling. Taken together, we demonstrate that CaMKII is not critically involved in acute I/R-induced damage but in the process of post-infarct remodeling and inflammatory processes. © 2014 The Authors. Published under the terms of the CC BY 4.0 license.

  16. Cannabis Use: Signal of Increasing Risk of Serious Cardiovascular Disorders

    PubMed Central

    Jouanjus, Emilie; Lapeyre‐Mestre, Maryse; Micallef, Joelle

    2014-01-01

    Background Cannabis is known to be associated with neuropsychiatric problems, but less is known about complications affecting other specified body systems. We report and analyze 35 recent remarkable cardiovascular complications following cannabis use. Methods and Results In France, serious cases of abuse and dependence in response to the use of psychoactive substances must be reported to the national system of the French Addictovigilance Network. We identified all spontaneous reports of cardiovascular complications related to cannabis use collected by the French Addictovigilance Network from 2006 to 2010. We described the clinical characteristics of these cases and their evolution: 1.8% of all cannabis‐related reports (35/1979) were cardiovascular complications, with patients being mostly men (85.7%) and of an average age of 34.3 years. There were 22 cardiac complications (20 acute coronary syndromes), 10 peripheral complications (lower limb or juvenile arteriopathies and Buerger‐like diseases), and 3 cerebral complications (acute cerebral angiopathy, transient cortical blindness, and spasm of cerebral artery). In 9 cases, the event led to patient death. Conclusions Increased reporting of cardiovascular complications related to cannabis and their extreme seriousness (with a death rate of 25.6%) indicate cannabis as a possible risk factor for cardiovascular disease in young adults, in line with previous findings. Given that cannabis is perceived to be harmless by the general public and that legalization of its use is debated, data concerning its danger must be widely disseminated. Practitioners should be aware that cannabis may be a potential triggering factor for cardiovascular complications in young people. PMID:24760961

  17. Ginkgo biloba extract EGb761 attenuates brain death-induced renal injury by inhibiting pro-inflammatory cytokines and the SAPK and JAK-STAT signalings

    PubMed Central

    Li, Yifu; Xiong, Yunyi; Zhang, Huanxi; Li, Jun; Wang, Dong; Chen, Wenfang; Yuan, Xiaopeng; Su, Qiao; Li, Wenwen; Huang, Huiting; Bi, Zirong; Liu, Longshan; Wang, Changxi

    2017-01-01

    This study aimed to investigate the protective effects of EGb761, a Ginkgo Biloba extract, against brain death-induced kidney injury. Sixty male Sprague Dawley rats were randomly divided into six groups: sham, brain-death (BD), BD + EGb b48h (48 hours before BD), BD + EGb 2 h (2 hours after BD), BD + EGb 1 h, and BD + EGb 0.5 h. Six hours after BD, serum sample and kidney tissues were collected for analyses. The levels of blood urea nitrogen (BUN) and serum creatinine significantly elevated in the BD group than in sham group. In all the EGb761-treated BD animals except for the BD + Gb 2 h group, the levels of BUN and serum creatinine significantly reduced (all P < 0.01). EGb761 attenuated tubular injury and lowered the histological score. In addition, the longer duration of drug treatment was, the better protective efficacy could be observed. EGb761 significantly reduced IL-1β, IL-6, TNF-α, MCP-1, IP-10 mRNA expression and macrophage infiltration in the kidney. EGb761 treatment at 48 hour before brain death significantly attenuate the levels of p-JNK-MAPK, p-p38-MAPK, and p-STAT3 proteins (all P < 0.05, compared to BD group). In summary, our data showed that EGb761 treatment protected donor kidney from BD-induced damages by blocking SAPK and JAK-STAT signalings. Early administration of EGb761 can provide better protective efficacy. PMID:28332628

  18. Increased Eotaxin and MCP-1 Levels in Serum from Individuals with Periodontitis and in Human Gingival Fibroblasts Exposed to Pro-Inflammatory Cytokines

    PubMed Central

    Sulniute, Rima; Palmqvist, Py; Majster, Mirjam; Holm, Cecilia Koskinen; Zwicker, Stephanie; Clark, Reuben; Önell, Sebastian; Johansson, Ingegerd; Lerner, Ulf H.; Lundberg, Pernilla

    2015-01-01

    Periodontitis is a chronic inflammatory disease of tooth supporting tissues resulting in periodontal tissue destruction, which may ultimately lead to tooth loss. The disease is characterized by continuous leukocyte infiltration, likely mediated by local chemokine production but the pathogenic mechanisms are not fully elucidated. There are no reliable serologic biomarkers for the diagnosis of periodontitis, which is today based solely on the degree of local tissue destruction, and there is no available biological treatment tool. Prompted by the increasing interest in periodontitis and systemic inflammatory mediators we mapped serum cytokine and chemokine levels from periodontitis subjects and healthy controls. We used multivariate partial least squares (PLS) modeling and identified monocyte chemoattractant protein-1 (MCP-1) and eotaxin as clearly associated with periodontitis along with C-reactive protein (CRP), years of smoking and age, whereas the number of remaining teeth was associated with being healthy. Moreover, body mass index correlated significantly with serum MCP-1 and CRP, but not with eotaxin. We detected higher MCP-1 protein levels in inflamed gingival connective tissue compared to healthy but the eotaxin levels were undetectable. Primary human gingival fibroblasts displayed strongly increased expression of MCP-1 and eotaxin mRNA and protein when challenged with tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β), key mediators of periodontal inflammation. We also demonstrated that the upregulated chemokine expression was dependent on the NF-κΒ pathway. In summary, we identify higher levels of CRP, eotaxin and MCP-1 in serum of periodontitis patients. This, together with our finding that both CRP and MCP-1 correlates with BMI points towards an increased systemic inflammatory load in patients with periodontitis and high BMI. Targeting eotaxin and MCP-1 in periodontitis may result in reduced leukocyte infiltration and inflammation in

  19. Increased Eotaxin and MCP-1 Levels in Serum from Individuals with Periodontitis and in Human Gingival Fibroblasts Exposed to Pro-Inflammatory Cytokines.

    PubMed

    Boström, Elisabeth A; Kindstedt, Elin; Sulniute, Rima; Palmqvist, Py; Majster, Mirjam; Holm, Cecilia Koskinen; Zwicker, Stephanie; Clark, Reuben; Önell, Sebastian; Johansson, Ingegerd; Lerner, Ulf H; Lundberg, Pernilla

    2015-01-01

    Periodontitis is a chronic inflammatory disease of tooth supporting tissues resulting in periodontal tissue destruction, which may ultimately lead to tooth loss. The disease is characterized by continuous leukocyte infiltration, likely mediated by local chemokine production but the pathogenic mechanisms are not fully elucidated. There are no reliable serologic biomarkers for the diagnosis of periodontitis, which is today based solely on the degree of local tissue destruction, and there is no available biological treatment tool. Prompted by the increasing interest in periodontitis and systemic inflammatory mediators we mapped serum cytokine and chemokine levels from periodontitis subjects and healthy controls. We used multivariate partial least squares (PLS) modeling and identified monocyte chemoattractant protein-1 (MCP-1) and eotaxin as clearly associated with periodontitis along with C-reactive protein (CRP), years of smoking and age, whereas the number of remaining teeth was associated with being healthy. Moreover, body mass index correlated significantly with serum MCP-1 and CRP, but not with eotaxin. We detected higher MCP-1 protein levels in inflamed gingival connective tissue compared to healthy but the eotaxin levels were undetectable. Primary human gingival fibroblasts displayed strongly increased expression of MCP-1 and eotaxin mRNA and protein when challenged with tumor necrosis factor-α (TNF-α and interleukin-1β (IL-1β), key mediators of periodontal inflammation. We also demonstrated that the upregulated chemokine expression was dependent on the NF-κΒ pathway. In summary, we identify higher levels of CRP, eotaxin and MCP-1 in serum of periodontitis patients. This, together with our finding that both CRP and MCP-1 correlates with BMI points towards an increased systemic inflammatory load in patients with periodontitis and high BMI. Targeting eotaxin and MCP-1 in periodontitis may result in reduced leukocyte infiltration and inflammation in

  20. Double negative (IgG+IgD-CD27-) B cells are increased in a cohort of moderate-severe Alzheimer's disease patients and show a pro-inflammatory trafficking receptor phenotype.

    PubMed

    Bulati, Matteo; Buffa, Silvio; Martorana, Adriana; Gervasi, Francesco; Camarda, Cecilia; Azzarello, Delia Maria; Monastero, Roberto; Caruso, Calogero; Colonna-Romano, Giuseppina

    2015-01-01

    Alzheimer's disease (AD) is a progressive, irreversible, and debilitating disease for which no effective preventive or disease modifying therapies or treatments have so far been detected. The crucial step in AD pathogenesis is the production of amyloid-β42 peptide, which causes chronic inflammation. Activated cells in the central nervous system (CNS) produce pro-inflammatory mediators that lead to the recruitment of myeloid or lymphocytic cells. As a consequence, the communication between the CNS and peripheral blood of AD subjects could influence the lymphocyte distribution and/or the expression of phenotypic markers. In the present paper, we show a significant decrease in total CD19+ B lymphocytes and a remodeling of the B cell subpopulations in moderate-severe AD patients, compared with their coeval healthy controls and mild AD subjects. In particular, we report a significant reduction in naïve B cells (IgD+CD27-) and a simultaneous increase in double negative (DN, IgD-CD27-) memory B lymphocytes. We have also evaluated the expression of the pro-inflammatory chemokine receptors CCR6 and CCR7 in total and naïve/memory B cells from mild and moderate-severe AD patients, with the aim to detect a possible relationship between the trafficking profile and the stage of the disease. Our results demonstrate that both the amount and the trafficking profile of B cells are related to the severity of AD. The results discussed in this paper suggest a well-selected antibody panel should be used as an additional test for the identification of early AD.

  1. Sleep duration, cardiovascular disease, and proinflammatory biomarkers

    PubMed Central

    Grandner, Michael A; Sands-Lincoln, Megan R; Pak, Victoria M; Garland, Sheila N

    2013-01-01

    Habitual sleep duration has been associated with cardiometabolic disease, via several mechanistic pathways, but few have been thoroughly explored. One hypothesis is that short and/or long sleep duration is associated with a proinflammatory state, which could increase risk for cardiovascular and metabolic diseases. This hypothesis has been largely explored in the context of experimental sleep deprivation studies which have attempted to demonstrate changes in proinflammatory markers following acute sleep loss in the laboratory. Despite the controlled environment available in these studies, samples tend to lack generalization to the population at large and acute sleep deprivation may not be a perfect analog for short sleep. To address these limitations, population based studies have explored associations between proinflammatory markers and habitual sleep duration. This review summarizes what is known from experimental and cross-sectional studies about the association between sleep duration, cardiovascular disease, and proinflammatory biomarkers. First, the association between sleep duration with both morbidity and mortality, with a focus on cardiovascular disease, is reviewed. Then, a brief review of the potential role of proinflammatory markers in cardiovascular disease is presented. The majority of this review details specific findings related to specific molecules, including tumor necrosis factor-α, interleukins-1, -6, and -17, C-reactive protein, coagulation molecules, cellular adhesion molecules, and visfatin. Finally, a discussion of the limitations of current studies and future directions is provided. PMID:23901303

  2. A Double-Inactivated Severe Acute Respiratory Syndrome Coronavirus Vaccine Provides Incomplete Protection in Mice and Induces Increased Eosinophilic Proinflammatory Pulmonary Response upon Challenge▿

    PubMed Central

    Bolles, Meagan; Deming, Damon; Long, Kristin; Agnihothram, Sudhakar; Whitmore, Alan; Ferris, Martin; Funkhouser, William; Gralinski, Lisa; Totura, Allison; Heise, Mark; Baric, Ralph S.

    2011-01-01

    Severe acute respiratory syndrome coronavirus (SARS-CoV) is an important emerging virus that is highly pathogenic in aged populations and is maintained with great diversity in zoonotic reservoirs. While a variety of vaccine platforms have shown efficacy in young-animal models and against homologous viral strains, vaccine efficacy has not been thoroughly evaluated using highly pathogenic variants that replicate the acute end stage lung disease phenotypes seen during the human epidemic. Using an adjuvanted and an unadjuvanted double-inactivated SARS-CoV (DIV) vaccine, we demonstrate an eosinophilic immunopathology in aged mice comparable to that seen in mice immunized with the SARS nucleocapsid protein, and poor protection against a nonlethal heterologous challenge. In young and 1-year-old animals, we demonstrate that adjuvanted DIV vaccine provides protection against lethal disease in young animals following homologous and heterologous challenge, although enhanced immune pathology and eosinophilia are evident following heterologous challenge. In the absence of alum, DIV vaccine performed poorly in young animals challenged with lethal homologous or heterologous strains. In contrast, DIV vaccines (both adjuvanted and unadjuvanted) performed poorly in aged-animal models. Importantly, aged animals displayed increased eosinophilic immune pathology in the lungs and were not protected against significant virus replication. These data raise significant concerns regarding DIV vaccine safety and highlight the need for additional studies of the molecular mechanisms governing DIV-induced eosinophilia and vaccine failure, especially in the more vulnerable aged-animal models of human disease. PMID:21937658

  3. Lactobacillus acidophilus Increases the Anti-apoptotic Micro RNA-21 and Decreases the Pro-inflammatory Micro RNA-155 in the LPS-Treated Human Endothelial Cells.

    PubMed

    Kalani, Mehdi; Hodjati, Hossein; Sajedi Khanian, Mahdi; Doroudchi, Mehrnoosh

    2016-06-01

    Given the anti-inflammatory and protective role of probiotics in atherosclerosis and the regulatory role of micro RNA (miRNA) in endothelial cell (dys) functions, this study aimed to investigate the effect of Lactobacillus acidophilus (La) on cellular death and the expression of miRNA-21, 92a, 155, and 663 in human umbilical vein endothelial cell (HUVEC) induced by Escherichia coli lipopolysaccharide (Ec-LPS). LPS-treated and untreated HUVECs were cultured in the presence of different La conditions such as La-conditioned media (LaCM), La water extract (LaWE), La culture-filtered (LaFS) and unfiltered supernatants (LaUFS). After 24 h, apoptosis, necrosis and the levels of the mentioned miRNAs were measured using flow cytometry and real-time PCR methods, respectively. LaCM decreased apoptosis, necrosis and inflammatory miR-155 and conversely increased anti-apoptotic miR-21 in Ec-LPS-treated HUVECs. Association analysis revealed negative correlations between necrosis and the levels of miR-21, miR-92a, and miR-155. The beneficial effects of L. acidophilus on the ECs death and expression of atherosclerosis related miRNAs in these cells imply a new aspect of its regulation in cardiovascular diseases rather than previously described ones and suggest this probiotic bacterium as a candidate in the preventative therapy of atherosclerosis.

  4. Electromagnetic Signals and Earthquakes 2.0: Increasing Signals and Reducing Noise

    NASA Astrophysics Data System (ADS)

    Dunson, J. C.; Bleier, T.; Heraud, J. A.; Muller, S.; Lindholm, C.; Christman, L.; King, R.; Lemon, J.

    2013-12-01

    QuakeFinder has an international network of 150+ Magnetometers and air conductivity instruments located in California, Peru, Chile, Taiwan, and Greece. Since 2000, QuakeFinder has been collecting electromagnetic data and applying simple algorithms to identify and characterize electromagnetic signals that occur in the few weeks prior to earthquakes greater than M4.5. In this presentation, we show refinements to several aspects of our signal identification techniques that enhance detection of pre-earthquake patterns. Our magnetometers have been improved to show longer pulses, and we are now using second generation algorithms that have been refined to detect the proper shape of the earthquake-generated pulses and to allow individual site adjustments. Independent lightning strike data has also now been included to mask out lightning based on amplitude and distance from a given instrument site. Direction of arrival (Azimuth) algorithms have been added to identify patterns of pulse clustering that occur prior to nearby earthquakes. Likewise, positive and negative air ion concentration detection has been improved by building better enclosures, using stainless screens to eliminate insects and some dirt sources, conformal coating PC boards to reduce moisture contamination, and filtering out contaminated data segments based on relative humidity measurements at each site. Infra Red data from the western GOES satellite has been time-filtered, cloud-filtered, and compared to 3 year averages of each pixel's output (by seasonal month) to arrive at a relevant comparison baseline for each night's temperature/cooling slope. All these efforts have helped improve the detection of multiple, nearly simultaneous, electromagnetic signals due to earthquake preparation processes, while reducing false positive indications due to environmental noise sources.

  5. WIN-34B May Have Analgesic and Anti-Inflammatory Effects by Reducing the Production of Pro-Inflammatory Mediators in Cells via Inhibition of IκB Signaling Pathways

    PubMed Central

    Kim, Kyoung Soo; Choi, Hyun Mi; Yang, Hyung-In; Yoo, Myung Chul

    2012-01-01

    WIN-34B showed analgesic and anti-inflammatory effects in various animal models of pain and osteoarthritis. However, the molecular mechanism by which WIN-34B inhibits pain and inflammation in vivo remains to be elucidated. We investigated the molecular mechanisms of the actions of WIN-34B using various in vitro models using fibroblast-like synoviocytes from patients with rheumatoid arthritis (RA FLSs), RAW264.7 cells and peritoneal macrophages. WIN-34B inhibited the level of IL-6, PGE2, and MMP-13 in IL-1β-stimulated RA FLSs in a dose-dependent manner. The mRNA levels were also inhibited by WIN-34B. The level of PGE2, NO, IL-1β, and TNF-α were inhibited by WIN-34B at different concentrations in LPS-stimulated RAW264.7 cells. The production of NO and PGE2 was inhibited by WIN-34B in a dose-dependent manner in LPS-stimulated peritoneal macrophages. All of these effects were comparable to the positive control, celecoxib or indomethacin. IκB signaling pathways were inhibited by WIN-34B, and the migration of NF-κB into the nucleus was inhibited, which is consistent with the degradation of IκB-α. Taken together, the results suggest that WIN-34B has potential as a therapeutic drug to reduce pain and inflammation by inhibiting the production of pro-inflammatory mediators. PMID:24116274

  6. GM-CSF increases LPS-induced production of proinflammatory mediators via upregulation of TLR4 and CD14 in murine microglia

    PubMed Central

    2012-01-01

    Background Microglia are resident macrophage-like cells in the central nervous system (CNS) and cause innate immune responses via the LPS receptors, Toll-like receptor (TLR) 4 and CD14, in a variety of neuroinflammatory disorders including bacterial infection, Alzheimer’s disease, and amyotrophic lateral sclerosis. Granulocyte macrophage-colony stimulating factor (GM-CSF) activates microglia and induces inflammatory responses via binding to GM-CSF receptor complex composed of two different subunit GM-CSF receptor α (GM-CSFRα) and common β chain (βc). GM-CSF has been shown to be associated with neuroinflammatory responses in multiple sclerosis and Alzheimer’s disease. However, the mechanisms how GM-CSF promotes neuroinflammation still remain unclear. Methods Microglia were stimulated with 20 ng/ml GM-CSF and the levels of TLR4 and CD14 expression were evaluated by RT-PCR and flowcytometry. LPS binding was analyzed by flowcytometry. GM-CSF receptor complex was analyzed by immunocytechemistry. The levels of IL-1β, IL-6 and TNF-α in culture supernatant of GM-CSF-stimulated microglia and NF-κB nuclear translocation were determined by ELISA. Production of nitric oxide (NO) was measured by the Griess method. The levels of p-ERK1/2, ERK1/2, p-p38 and p38 were assessed by Western blotting. Statistically significant differences between experimental groups were determined by one-way ANOVA followed by Tukey test for multiple comparisons. Results GM-CSF receptor complex was expressed in microglia. GM-CSF enhanced TLR4 and CD14 expressions in microglia and subsequent LPS-binding to the cell surface. In addition, GM-CSF priming increased LPS-induced NF-κB nuclear translocation and production of IL-1β, IL-6, TNF-α and NO by microglia. GM-CSF upregulated the levels of p-ERK1/2 and p-p38, suggesting that induction of TLR4 and CD14 expression by GM-CSF was mediated through ERK1/2 and p38, respectively. Conclusions These results suggest that GM-CSF upregulates TLR4 and

  7. Pro-inflammatory mechanisms in sepsis.

    PubMed

    Chong, Deborah L W; Sriskandan, Shiranee

    2011-01-01

    Sepsis is characterised by a hyper-inflammatory response due to microbial infection. We here review our current understanding of host mechanisms employed to mediate this hyper-inflammatory response, drawing together current knowledge pertaining to pathogen recognition and host pro-inflammatory response. Recognition of microbial derived ligands by pattern recognition receptors (PRRs) is a key step in initiating pro-inflammatory signalling pathways. Examples of PRRs linked to the aetiology of sepsis include Toll-like, C-type lectin, RIG-1-like and also Nod-like receptors, which are involved in the formation of the inflammasome, crucial for the maturation of some pro-inflammatory cytokines. Bacterial superantigens have evolved to exploit host MHC class II and T cell receptors (normally considered part of the adaptive immune response) as innate PRRs to propagate a so-called 'cytokine storm', while synergy between different microbial ligands and host-derived alarmins can augment the inflammatory response still further through as yet poorly understood interactions. The host pro-inflammatory response results in the characteristic features of inflammation: rubor, calor, dolor, and tumor. We will review herein the key mediators of inflammation in sepsis, identifying their overlapping and intersecting roles in vascular changes in tone, endothelial permeability, coagulation and contact activation, leukocyte mobilisation and activation. Copyright © 2011 S. Karger AG, Basel.

  8. Mycobacterium tuberculosis Hip1 Dampens Macrophage Proinflammatory Responses by Limiting Toll-Like Receptor 2 Activation▿

    PubMed Central

    Madan-Lala, Ranjna; Peixoto, Katia Vitorello; Re, Fabio; Rengarajan, Jyothi

    2011-01-01

    Mycobacterium tuberculosis is a highly successful human pathogen that evades host innate immunity by interfering with macrophage functions. In addition to avoiding macrophage microbicidal activities, M. tuberculosis triggers secretion of proinflammatory cytokines and chemokines in macrophages. The levels of proinflammatory cytokines induced by clinical M. tuberculosis isolates are thought to play an important role in determining tuberculosis disease progression and severity, but the mechanisms by which M. tuberculosis modulates the magnitude of inflammatory responses remain unclear. Here we show that M. tuberculosis restricts robust macrophage activation and dampens proinflammatory responses through the cell envelope-associated serine hydrolase Hip1 (hydrolase important for pathogenesis 1). By transcriptionally profiling macrophages infected with either wild-type or hip1 mutant bacteria, we found that the hip1 mutant induced earlier and significantly higher levels of several proinflammatory cytokines and chemokines. We show that increased activation of Toll-like receptor 2 (TLR2)- and MyD88-dependent signaling pathways mediates the enhanced cytokine secretion induced by the hip1 mutant. Thus, Hip1 restricts the onset and magnitude of proinflammatory cytokines by limiting TLR2-dependent activation. We also show that Hip1 dampens TLR2-independent activation of the inflammasome and limits secretion of interleukin-18 (IL-18). Dampening of TLR2 signaling does not require viable M. tuberculosis or phagocytosis but does require Hip1 catalytic activity. We propose that M. tuberculosis restricts proinflammatory responses by masking cell surface interactions between TLR2 agonists on M. tuberculosis and TLR2 on macrophages. This strategy may allow M. tuberculosis to evade early detection by host immunity, delay the onset of adaptive immune responses, and accelerate disease progression. PMID:21947769

  9. Role of ceramide in lipopolysaccharide (LPS)-induced signaling. LPS increases ceramide rather than acting as a structural homolog.

    PubMed

    MacKichan, M L; DeFranco, A L

    1999-01-15

    Ceramide and ceramide-activated enzymes have been implicated in responses to bacterial lipopolysaccharide (LPS) and the proinflammatory cytokines tumor necrosis factor-alpha (TNF) and interleukin-1beta (IL-1). Although TNF and IL-1 cause elevation of cellular ceramide, which is thought to act as a second messenger, LPS has been proposed to signal by virtue of structural similarity to ceramide. We have investigated the relationship between ceramide and LPS by comparing the effects of a cell-permeable ceramide analog (C2-ceramide) and LPS on murine macrophage cell lines and by measuring ceramide levels in macrophages exposed to LPS. We found that while both C2-ceramide and LPS activated c-Jun N-terminal kinase (JNK), only LPS also activated extracellular signal-regulated kinases (ERKs). C2-ceramide was also unable to activate NF-kappaB, a transcription factor important for LPS-induced gene expression. Upon measurement of cellular ceramide in macrophage lines, we observed a small but rapid rise in ceramide, similar to that seen upon IL-1 or TNF treatment, suggesting LPS induces an increase in ceramide rather than interacting directly with ceramide-responsive enzymes. We found that C2-ceramide activated JNK and induced growth arrest in macrophages cell lines from both normal mice (Lpsn) and mice genetically unresponsive to LPS (Lpsd), whereas only Lpsn macrophages made these responses to LPS. Surprisingly, LPS treatment of Lpsd macrophages induced a rise in ceramide similar to that observed in LPS-responsive cells. These results indicate that the wild type Lps allele is not required for LPS-induced ceramide generation and suggest that ceramide elevation alone is insufficent stimulus for most responses to LPS.

  10. Acylcarnitines activate pro-inflammatory signaling pathways

    USDA-ARS?s Scientific Manuscript database

    Incomplete beta-oxidation of fatty acids in mitochondria is a feature of insulin resistance and type 2 diabetes mellitus (T2DM) and the resulting metabolic by-products, medium- and long-chain acylcarnitines are shown to be elevated. In preliminary studies, mixed isomers of C12- or C14-carnitine act...

  11. Human eosinophils are direct targets to nanoparticles: Zinc oxide nanoparticles (ZnO) delay apoptosis and increase the production of the pro-inflammatory cytokines IL-1β and IL-8.

    PubMed

    Silva, Luis Rafael; Girard, Denis

    2016-09-30

    Zinc oxide NPs (ZnO) have been recently proposed as novel candidates for the treatment of allergic inflammatory diseases. Paradoxically, recent data suggested that ZnO could cause eosinophilic airway inflammation in rodents. Despite the above observations, there are currently no studies reporting direct interaction between a given NP and human eosinophils themselves. In this study, freshly isolated human eosinophils were incubated with ZnO and several cellular functions were studied. We found that ZnO delay human eosinophil apoptosis, partially by inhibiting caspases and by preventing caspase-4 and Bcl-xL degradation. ZnO do not induce production of reactive oxygen species but increase de novo protein synthesis. In addition, ZnO were found to increase the production of the proinflammatory IL-1β and IL-8 cytokines. Using a pharmacological approach, we demonstrated that inhibition of caspase-1 reversed the ability of ZnO to induce IL-1β and IL-8 production, whereas inhibition of caspase-4 only reversed that of IL-8. Our results indicate the necessity of conducting studies to determine the potential of using NP as nanotherapies, particularly in diseases in which eosinophils may be involved. We conclude that, indeed, human eosinophils represent potential new direct targets to NPs, ZnO in the present case.

  12. Field Crickets Compensate for Unattractive Static Long-Distance Call Components by Increasing Dynamic Signalling Effort

    PubMed Central

    McAuley, Emily M.

    2016-01-01

    The evolution of multiple sexual signals presents a dilemma since individuals selecting a mate should pay attention to the most honest signal and ignore the rest; however, multiple signals may evolve if, together, they provide more information to the receiver than either one would alone. Static and dynamic signals, for instance, can act as multiple messages, providing information on different aspects of signaller quality that reflect condition at different time scales. While the nature of static signals makes them difficult or impossible for individuals to augment, dynamic signals are much more susceptible to temporary fluctuations in effort. We investigated whether male Texas field crickets, Gryllus texensis, that produce unattractive static signals compensate by dynamically increasing their calling effort. Our findings lend partial support to the compensation hypothesis, as males that called at unattractive carrier frequencies (a static trait) spent more time calling each night (a dynamic trait). Interestingly, this finding was most pronounced in males that called with attractive pulse characteristics (static traits) but did not occur in males that called with unattractive pulse characteristics. Males that signalled with unattractive pulse characteristics (duration and pause) spent less time calling through the night. Our correlative findings on wild caught males suggest that only males that signal with attractive pulse characteristics may be able to afford to pay the costs of both trait exaggeration and increased calling effort to compensate for poor carrier frequencies. PMID:27936045

  13. Field Crickets Compensate for Unattractive Static Long-Distance Call Components by Increasing Dynamic Signalling Effort.

    PubMed

    McAuley, Emily M; Bertram, Susan M

    2016-01-01

    The evolution of multiple sexual signals presents a dilemma since individuals selecting a mate should pay attention to the most honest signal and ignore the rest; however, multiple signals may evolve if, together, they provide more information to the receiver than either one would alone. Static and dynamic signals, for instance, can act as multiple messages, providing information on different aspects of signaller quality that reflect condition at different time scales. While the nature of static signals makes them difficult or impossible for individuals to augment, dynamic signals are much more susceptible to temporary fluctuations in effort. We investigated whether male Texas field crickets, Gryllus texensis, that produce unattractive static signals compensate by dynamically increasing their calling effort. Our findings lend partial support to the compensation hypothesis, as males that called at unattractive carrier frequencies (a static trait) spent more time calling each night (a dynamic trait). Interestingly, this finding was most pronounced in males that called with attractive pulse characteristics (static traits) but did not occur in males that called with unattractive pulse characteristics. Males that signalled with unattractive pulse characteristics (duration and pause) spent less time calling through the night. Our correlative findings on wild caught males suggest that only males that signal with attractive pulse characteristics may be able to afford to pay the costs of both trait exaggeration and increased calling effort to compensate for poor carrier frequencies.

  14. Whole Cigarette Smoke Increased the Expression of TLRs, HBDs, and Proinflammory Cytokines by Human Gingival Epithelial Cells through Different Signaling Pathways

    PubMed Central

    Semlali, Abdelhabib; Witoled, Chmielewski; Alanazi, Mohammed; Rouabhia, Mahmoud

    2012-01-01

    The gingival epithelium is becoming known as a regulator of the oral innate immune responses to a variety of insults such as bacteria and chemicals, including those chemicals found in cigarette smoke. We investigated the effects of whole cigarette smoke on cell-surface-expressed Toll-like receptors (TLR)-2, −4 and −6, human β-defensin (HBD) and proinflammatory cytokine expression and production in primary human gingival epithelial cells. Whole cigarette smoke was shown to increase TLR2, TLR4 and TLR6 expression. Cigarette smoke led to ERK1/2, p38 and JNK phosphorylation in conjunction with nuclear factor-κB (NFκB) translocation into the nucleus. TLR expression following cigarette smoke exposure was down regulated by the use of ERK1/2, p38, JNK MAP kinases, and NFκB inhibitors, suggesting the involvement of these signaling pathways in the cellular response against cigarette smoke. Cigarette smoke also promoted HBD2, HBD3, IL-1β, and IL-6 expression through the ERK1/2 and NFκB pathways. Interestingly, the modulation of TLR, HBD, and cytokine expression was maintained long after the gingival epithelial cells were exposed to smoke. By promoting TLR, HBDs, and proinflammatory cytokine expression and production, cigarette smoke may contribute to innate immunity dysregulation, which may have a negative effect on human health. PMID:23300722

  15. Whole cigarette smoke increased the expression of TLRs, HBDs, and proinflammory cytokines by human gingival epithelial cells through different signaling pathways.

    PubMed

    Semlali, Abdelhabib; Witoled, Chmielewski; Alanazi, Mohammed; Rouabhia, Mahmoud

    2012-01-01

    The gingival epithelium is becoming known as a regulator of the oral innate immune responses to a variety of insults such as bacteria and chemicals, including those chemicals found in cigarette smoke. We investigated the effects of whole cigarette smoke on cell-surface-expressed Toll-like receptors (TLR)-2, -4 and -6, human β-defensin (HBD) and proinflammatory cytokine expression and production in primary human gingival epithelial cells. Whole cigarette smoke was shown to increase TLR2, TLR4 and TLR6 expression. Cigarette smoke led to ERK1/2, p38 and JNK phosphorylation in conjunction with nuclear factor-κB (NFκB) translocation into the nucleus. TLR expression following cigarette smoke exposure was down regulated by the use of ERK1/2, p38, JNK MAP kinases, and NFκB inhibitors, suggesting the involvement of these signaling pathways in the cellular response against cigarette smoke. Cigarette smoke also promoted HBD2, HBD3, IL-1β, and IL-6 expression through the ERK1/2 and NFκB pathways. Interestingly, the modulation of TLR, HBD, and cytokine expression was maintained long after the gingival epithelial cells were exposed to smoke. By promoting TLR, HBDs, and proinflammatory cytokine expression and production, cigarette smoke may contribute to innate immunity dysregulation, which may have a negative effect on human health.

  16. Ethanol-induced erectile dysfunction and increased expression of pro-inflammatory proteins in the rat cavernosal smooth muscle are mediated by NADPH oxidase-derived reactive oxygen species.

    PubMed

    Leite, Letícia N; do Vale, Gabriel T; Simplicio, Janaina A; De Martinis, Bruno S; Carneiro, Fernando S; Tirapelli, Carlos R

    2017-06-05

    Ethanol consumption is associated with an increased risk of erectile dysfunction (ED), but the molecular mechanisms through which ethanol causes ED remain elusive. Reactive oxygen species are described as mediators of ethanol-induced cell toxicity/damage in distinctive tissues. The enzyme NADPH oxidase is the main source of reactive oxygen species in the endothelium and vascular smooth muscle cells and ethanol is described to increase NADPH oxidase activation and reactive oxygen species generation. This study evaluated the contribution of NADPH oxidase-derived reactive oxygen species to ethanol-induced ED, endothelial dysfunction and production of pro-inflammatory and redox-sensitive proteins in the rat cavernosal smooth muscle (CSM). Male Wistar rats were treated with ethanol (20% v/v) or ethanol plus apocynin (30mg/kg/day; p.o. gavage) for six weeks. Apocynin prevented both the decreased in acetylcholine-induced relaxation and intracavernosal pressure induced by ethanol. Ethanol increased superoxide anion (O2(-)) generation and catalase activity in CSM, and treatment with apocynin prevented these responses. Similarly, apocynin prevented the ethanol-induced decreased of nitrate/nitrite (NOx), hydrogen peroxide (H2O2) and SOD activity. Treatment with ethanol increased p47phox translocation to the membrane as well as the expression of Nox2, COX-1, catalase, iNOS, ICAM-1 and p65. Apocynin prevented the effects of ethanol on protein expression and p47phox translocation. Finally, treatment with ethanol increased both TNF-α production and neutrophil migration in CSM. The major new finding of this study is that NADPH oxidase-derived reactive oxygen species play a role on chronic ethanol consumption-induced ED and endothelial dysfunction in the rat CSM. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. Sodium chloride promotes pro-inflammatory macrophage polarization thereby aggravating CNS autoimmunity.

    PubMed

    Hucke, Stephanie; Eschborn, Melanie; Liebmann, Marie; Herold, Martin; Freise, Nicole; Engbers, Annika; Ehling, Petra; Meuth, Sven G; Roth, Johannes; Kuhlmann, Tanja; Wiendl, Heinz; Klotz, Luisa

    2016-02-01

    The increasing incidence in Multiple Sclerosis (MS) during the last decades in industrialized countries might be linked to a change in dietary habits. Nowadays, enhanced salt content is an important characteristic of Western diet and increased dietary salt (NaCl) intake promotes pathogenic T cell responses contributing to central nervous system (CNS) autoimmunity. Given the importance of macrophage responses for CNS disease propagation, we addressed the influence of salt consumption on macrophage responses in CNS autoimmunity. We observed that EAE-diseased mice receiving a NaCl-high diet showed strongly enhanced macrophage infiltration and activation within the CNS accompanied by disease aggravation during the effector phase of EAE. NaCl treatment of macrophages elicited a strong pro-inflammatory phenotype characterized by enhanced pro-inflammatory cytokine production, increased expression of immune-stimulatory molecules, and an antigen-independent boost of T cell proliferation. This NaCl-induced pro-inflammatory macrophage phenotype was accompanied by increased activation of NF-kB and MAPK signaling pathways. The pathogenic relevance of NaCl-conditioned macrophages is illustrated by the finding that transfer into EAE-diseased animals resulted in significant disease aggravation compared to untreated macrophages. Importantly, also in human monocytes, NaCl promoted a pro-inflammatory phenotype that enhanced human T cell proliferation. Taken together, high dietary salt intake promotes pro-inflammatory macrophages that aggravate CNS autoimmunity. Together with other studies, these results underline the need to further determine the relevance of increased dietary salt intake for MS disease severity.

  18. Increased signaling entropy in cancer requires the scale-free property of protein interaction networks

    PubMed Central

    Teschendorff, Andrew E.; Banerji, Christopher R. S.; Severini, Simone; Kuehn, Reimer; Sollich, Peter

    2015-01-01

    One of the key characteristics of cancer cells is an increased phenotypic plasticity, driven by underlying genetic and epigenetic perturbations. However, at a systems-level it is unclear how these perturbations give rise to the observed increased plasticity. Elucidating such systems-level principles is key for an improved understanding of cancer. Recently, it has been shown that signaling entropy, an overall measure of signaling pathway promiscuity, and computable from integrating a sample's gene expression profile with a protein interaction network, correlates with phenotypic plasticity and is increased in cancer compared to normal tissue. Here we develop a computational framework for studying the effects of network perturbations on signaling entropy. We demonstrate that the increased signaling entropy of cancer is driven by two factors: (i) the scale-free (or near scale-free) topology of the interaction network, and (ii) a subtle positive correlation between differential gene expression and node connectivity. Indeed, we show that if protein interaction networks were random graphs, described by Poisson degree distributions, that cancer would generally not exhibit an increased signaling entropy. In summary, this work exposes a deep connection between cancer, signaling entropy and interaction network topology. PMID:25919796

  19. Alcoholism: A systemic proinflammatory condition

    PubMed Central

    González-Reimers, Emilio; Santolaria-Fernández, Francisco; Martín-González, María Candelaria; Fernández-Rodríguez, Camino María; Quintero-Platt, Geraldine

    2014-01-01

    Excessive ethanol consumption affects virtually any organ, both by indirect and direct mechanisms. Considerable research in the last two decades has widened the knowledge about the paramount importance of proinflammatory cytokines and oxidative damage in the pathogenesis of many of the systemic manifestations of alcoholism. These cytokines derive primarily from activated Kupffer cells exposed to Gram-negative intestinal bacteria, which reach the liver in supra-physiological amounts due to ethanol-mediated increased gut permeability. Reactive oxygen species (ROS) that enhance the inflammatory response are generated both by activation of Kupffer cells and by the direct metabolic effects of ethanol. The effects of this increased cytokine secretion and ROS generation lie far beyond liver damage. In addition to the classic consequences of endotoxemia associated with liver cirrhosis that were described several decades ago, important research in the last ten years has shown that cytokines may also induce damage in remote organs such as brain, bone, muscle, heart, lung, gonads, peripheral nerve, and pancreas. These effects are even seen in alcoholics without significant liver disease. Therefore, alcoholism can be viewed as an inflammatory condition, a concept which opens the possibility of using new therapeutic weapons to treat some of the complications of this devastating and frequent disease. In this review we examine some of the most outstanding consequences of the altered cytokine regulation that occurs in alcoholics in organs other than the liver. PMID:25356029

  20. Alcoholism: a systemic proinflammatory condition.

    PubMed

    González-Reimers, Emilio; Santolaria-Fernández, Francisco; Martín-González, María Candelaria; Fernández-Rodríguez, Camino María; Quintero-Platt, Geraldine

    2014-10-28

    Excessive ethanol consumption affects virtually any organ, both by indirect and direct mechanisms. Considerable research in the last two decades has widened the knowledge about the paramount importance of proinflammatory cytokines and oxidative damage in the pathogenesis of many of the systemic manifestations of alcoholism. These cytokines derive primarily from activated Kupffer cells exposed to Gram-negative intestinal bacteria, which reach the liver in supra-physiological amounts due to ethanol-mediated increased gut permeability. Reactive oxygen species (ROS) that enhance the inflammatory response are generated both by activation of Kupffer cells and by the direct metabolic effects of ethanol. The effects of this increased cytokine secretion and ROS generation lie far beyond liver damage. In addition to the classic consequences of endotoxemia associated with liver cirrhosis that were described several decades ago, important research in the last ten years has shown that cytokines may also induce damage in remote organs such as brain, bone, muscle, heart, lung, gonads, peripheral nerve, and pancreas. These effects are even seen in alcoholics without significant liver disease. Therefore, alcoholism can be viewed as an inflammatory condition, a concept which opens the possibility of using new therapeutic weapons to treat some of the complications of this devastating and frequent disease. In this review we examine some of the most outstanding consequences of the altered cytokine regulation that occurs in alcoholics in organs other than the liver.

  1. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression

    SciTech Connect

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C.; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A.; Cardozo, Christopher P.

    2011-10-14

    Highlights: {yields} Nerve transection increased Notch signaling in paralyzed muscle. {yields} Nandrolone prevented denervation-induced Notch signaling. {yields} Nandrolone induced the expression of an inhibitor of the Notch signaling, Numb. {yields} Reduction of denervation-induced Notch signaling by nandrolone is likely through upregulation of Numb. -- Abstract: Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.

  2. The membrane expression of Neisseria meningitidis adhesin A (NadA) increases the proimmune effects of MenB OMVs on human macrophages, compared with NadA- OMVs, without further stimulating their proinflammatory activity on circulating monocytes.

    PubMed

    Tavano, Regina; Franzoso, Susanna; Cecchini, Paola; Cartocci, Elena; Oriente, Francesca; Aricò, Beatrice; Papini, Emanuele

    2009-07-01

    Hypervirulent MenB causing fatal human infections frequently display the oligomeric-coiled coil adhesin NadA, a 45-kDa intrinsic outer membrane protein implicated in binding to and invasion of respiratory epithelial cells. A recombinant soluble mutant lacking the 10-kDa COOH terminal membrane domain (NadA(Delta351-405)) also activates human monocytes/macrophages/DCs. As NadA is physiologically released during sepsis as part of OMVs, in this study, we tested the hypothesis that NadA(+) OMVs have an enhanced or modified proinflammatory/proimmune action compared with NadA(-) OMVs. To do this we investigated the activity of purified free NadA(Delta351-405) and of OMVs from MenB and Escherichia coli strains, expressing or not full-length NadA. NadA(Delta351-405) stimulated monocytes and macrophages to secrete cytokines (IL-1beta, TNF-alpha, IL-6, IL-12p40, IL-12p70, IL-10) and chemokines (IL-8, MIP-1alpha, MCP-1, RANTES), and full-length NadA improved MenB OMV activity, preferentially on macrophages, and only increased cytokine release. NadA(Delta351-405) induced the lymphocyte costimulant CD80 in monocytes and macrophages, and NadA(+) OMVs induced a wider set of molecules supporting antigen presentation (CD80, CD86, HLA-DR, and ICAM-1) more efficiently than NadA(-) OMVs only in macrophages. Moreover, membrane NadA effects, unlike NadA(Delta351-405) ones, were much less IFN-gamma-sensitive. The activity of NadA-positive E. coli OMVs was similar to that of control OMVs. NadA in MenB OMVs acted at adhesin concentrations approximately 10(6) times lower than those required to stimulate cells with free NadA(Delta351-405).

  3. Recombinant bovine respiratory syncytial virus with deletion of the SH gene induces increased apoptosis and pro-inflammatory cytokines in vitro, and is attenuated and induces protective immunity in calves.

    PubMed

    Taylor, Geraldine; Wyld, Sara; Valarcher, Jean-Francois; Guzman, Efrain; Thom, Michelle; Widdison, Stephanie; Buchholz, Ursula J

    2014-06-01

    Bovine respiratory syncytial virus (BRSV) causes inflammation and obstruction of the small airways, leading to severe respiratory disease in young calves. The virus is closely related to human (H)RSV, a major cause of bronchiolitis and pneumonia in young children. The ability to manipulate the genome of RSV has provided opportunities for the development of stable, live attenuated RSV vaccines. The role of the SH protein in the pathogenesis of BRSV was evaluated in vitro and in vivo using a recombinant (r)BRSV in which the SH gene had been deleted. Infection of bovine epithelial cells and monocytes with rBRSVΔSH, in vitro, resulted in an increase in apoptosis, and higher levels of TNF-α and IL-1β compared with cells infected with parental, wild-type (WT) rBRSV. Although replication of rBRSVΔSH and WT rBRSV, in vitro, were similar, the replication of rBRSVΔSH was moderately reduced in the lower, but not the upper, respiratory tract of experimentally infected calves. Despite the greater ability of rBRSVΔSH to induce pro-inflammatory cytokines, in vitro, the pulmonary inflammatory response in rBRSVΔSH-infected calves was significantly reduced compared with that in calves inoculated with WT rBRSV, 6 days previously. Virus lacking SH appeared to be as immunogenic and effective in inducing resistance to virulent virus challenge, 6 months later, as the parental rBRSV. These findings suggest that rBRSVΔSH may be an ideal live attenuated virus vaccine candidate, combining safety with a high level of immunogenicity.

  4. TNF-TNFR2/p75 signaling inhibits early and increases delayed nontargeted effects in bone marrow-derived endothelial progenitor cells.

    PubMed

    Sasi, Sharath P; Song, Jin; Park, Daniel; Enderling, Heiko; McDonald, J Tyson; Gee, Hannah; Garrity, Brittany; Shtifman, Alexander; Yan, Xinhua; Walsh, Kenneth; Natarajan, Mohan; Kishore, Raj; Goukassian, David A

    2014-05-16

    TNF-α, a pro-inflammatory cytokine, is highly expressed after being irradiated (IR) and is implicated in mediating radiobiological bystander responses (RBRs). Little is known about specific TNF receptors in regulating TNF-induced RBR in bone marrow-derived endothelial progenitor cells (BM-EPCs). Full body γ-IR WT BM-EPCs showed a biphasic response: slow decay of p-H2AX foci during the initial 24 h and increase between 24 h and 7 days post-IR, indicating a significant RBR in BM-EPCs in vivo. Individual TNF receptor (TNFR) signaling in RBR was evaluated in BM-EPCs from WT, TNFR1/p55KO, and TNFR2/p75KO mice, in vitro. Compared with WT, early RBR (1-5 h) were inhibited in p55KO and p75KO EPCs, whereas delayed RBR (3-5 days) were amplified in p55KO EPCs, suggesting a possible role for TNFR2/p75 signaling in delayed RBR. Neutralizing TNF in γ-IR conditioned media (CM) of WT and p55KO BM-EPCs largely abolished RBR in both cell types. ELISA protein profiling of WT and p55KO EPC γ-IR-CM over 5 days showed significant increases in several pro-inflammatory cytokines, including TNF-α, IL-1α (Interleukin-1 alpha), RANTES (regulated on activation, normal T cell expressed and secreted), and MCP-1. In vitro treatments with murine recombinant (rm) TNF-α and rmIL-1α, but not rmMCP-1 or rmRANTES, increased the formation of p-H2AX foci in nonirradiated p55KO EPCs. We conclude that TNF-TNFR2 signaling may induce RBR in naïve BM-EPCs and that blocking TNF-TNFR2 signaling may prevent delayed RBR in BM-EPCs, conceivably, in bone marrow milieu in general. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  5. Demethoxycurcumin, a natural derivative of curcumin attenuates LPS-induced pro-inflammatory responses through down-regulation of intracellular ROS-related MAPK/NF-kappaB signaling pathways in N9 microglia induced by lipopolysaccharide.

    PubMed

    Zhang, Lijia; Wu, Chunfu; Zhao, Siqi; Yuan, Dan; Lian, Guoning; Wang, Xiaoxiao; Wang, Lihui; Yang, Jingyu

    2010-03-01

    Our previous report has showed that demethoxycurcumin (DMC), a natural derivative of curcumin (Cur), exhibited stronger inhibitory activity on nitric oxide (NO) and tumor necrosis factor-alpha (TNF-alpha) production compared with Cur in lipopolysaccharide (LPS) activated rat primary microglia. In the present study, the effect and possible mechanism of DMC on the production of pro-inflammatory mediators in LPS-activated N9 microglial cells were further investigated. The results showed that DMC significantly suppressed the NO production induced by LPS in N9 microglial cells through inhibiting the protein and mRNA expression of inducible NO synthase (iNOS). DMC also decreased LPS-induced TNF-alpha and IL-1beta expression at both transcriptional and protein level in a concentration-dependent manner. Further studies revealed that DMC blocked IkappaBalpha phosphorylation and degradation, inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs). Moreover, the level of intracellular reactive oxygen species (iROS) was significantly increased by LPS, which is mainly mediated by the up-regulated expression of gp91phox, the catalytic subunit of nicotinamide adenine dinucleotide phosphate reduced (NADPH) oxidase. Both DMC and Cur could markedly decrease iROS production and the expression of NADPH oxidase induced by LPS, with more potent inhibitory activity of DMC. In summary, these data suggest that DMC exerts its in vitro anti-inflammatory effect in LPS-activated N9 microglial cells by blocking nuclear factor-kappaB (NF-kappaB) and MAPKs activation, which may be partly due to its potent down-regulation of the NADPH-derived iROS production.

  6. Proinflammatory Cytokine Tumor Necrosis Factor (TNF)-like Weak Inducer of Apoptosis (TWEAK) Suppresses Satellite Cell Self-renewal through Inversely Modulating Notch and NF-κB Signaling Pathways*

    PubMed Central

    Ogura, Yuji; Mishra, Vivek; Hindi, Sajedah M.; Kuang, Shihuan; Kumar, Ashok

    2013-01-01

    Satellite cell self-renewal is an essential process to maintaining the robustness of skeletal muscle regenerative capacity. However, extrinsic factors that regulate self-renewal of satellite cells are not well understood. Here, we demonstrate that TWEAK cytokine reduces the proportion of Pax7+/MyoD− cells (an index of self-renewal) on myofiber explants and represses multiple components of Notch signaling in satellite cell cultures. The number of Pax7+ cells is significantly increased in skeletal muscle of TWEAK knock-out (KO) mice compared with wild-type in response to injury. Furthermore, Notch signaling is significantly elevated in cultured satellite cells and in regenerating myofibers of TWEAK-KO mice. Forced activation of Notch signaling through overexpression of the Notch1 intracellular domain (N1ICD) rescued the TWEAK-mediated inhibition of satellite cell self-renewal. TWEAK also activates the NF-κB transcription factor in satellite cells and inhibition of NF-κB significantly improved the number of Pax7+ cells in TWEAK-treated cultures. Furthermore, our results demonstrate that a reciprocal interaction between NF-κB and Notch signaling governs the inhibitory effect of TWEAK on satellite cell self-renewal. Collectively, our study demonstrates that TWEAK suppresses satellite cell self-renewal through activating NF-κB and repressing Notch signaling. PMID:24151074

  7. Fenretinide prevents obesity in aged female mice in association with increased retinoid and estrogen signaling.

    PubMed

    Shearer, Kirsty D; Morrice, Nicola; Henderson, Claire; Reekie, Jenny; Mcilroy, George D; McCaffery, Peter J; Delibegovic, Mirela; Mody, Nimesh

    2015-08-01

    The synthetic retinoid fenretinide (FEN) inhibits adiposity in male mice fed a high-fat diet (HFD) in association with alterations in retinoic acid (RA) signaling. Young female mice are protected from obesity via estrogen signaling. We, therefore, investigated whether FEN also influences adiposity in aged female mice differing in parity and whether such effects are mediated by retinoid and estrogen signaling. Aged nulliparous and parous female mice were maintained on HFD ± FEN, and adiposity was assessed. Quantitative polymerase chain reaction was performed on white adipose tissue (WAT), liver, and 3T3-L1 adipocytes treated with RA or FEN ± estrogen. Parous females were more obese than nulliparous mice independent of age. FEN-HFD prevented the HFD-induced increase in adiposity and leptin levels independently of parity. FEN-HFD induced retinoid-responsive genes in WAT and liver. Parous females had reduced expression of hepatic estrogen-responsive genes, but FEN-HFD up-regulated WAT Cyp19a1 and Esr2 in parous mice. Estrogen and RA acted synergistically to increase RA receptor-mediated gene expression in 3T3-L1 adipocytes. FEN increased Cyp19a1 and Esr2, similar to our findings in vivo. The prevention of adiposity by FEN in response to HFD in female mice seems to involve increased retinoid signaling in association with induction of local estrogen production and estrogen signaling in WAT. © 2015 The Obesity Society.

  8. The Interplay between Radioresistant Caco-2 Cells and the Immune System Increases Epithelial Layer Permeability and Alters Signaling Protein Spectrum

    PubMed Central

    Morini, Jacopo; Babini, Gabriele; Barbieri, Sofia; Baiocco, Giorgio; Ottolenghi, Andrea

    2017-01-01

    Colorectal cancer is one of the most frequent type of cancer, with a higher incidence in the developed countries. Colorectal cancer is usually managed with both surgeries, chemotherapy and radiotherapy. Radiotherapy has the well-known advantage of targeting the tumor, minimizing normal tissue exposure. Nevertheless, during radiation treatment, exposure of healthy tissues is of great concern, in particular because of the effects on the intestinal barrier functions and on cells belonging to the immune system. The functional role of intestinal barrier in avoiding paracellular trafficking and controlling bacterial spread from gut it is well known and it is due to the presence of tight junction complexes. However, intestinal barrier is fundamental in participating to the interplay with immune system, especially considering the gut-associated lymphoid tissue. Until few years ago, radiotherapy was considered to bear only a depressive action on the immune system. However, it is now recognized that the release of pro-inflammatory signals and phenotypic changes in tumoral cells due to ionizing radiation could trigger the immune system against the tumor. In this work, we address how intestinal barrier functions are perturbed by X-ray doses in the range 0–10 Gy, focusing on the interplay between tumoral cells and the immune system. To this aim, we adopted a coculture model in which Caco-2 cells can be grown in presence/absence of peripheral blood mononuclear cells (PBMC). We focused our attention on changes in the proliferation, trans-epithelial electrical resistance (TEER), cytokine release, and proteins of the junctional complexes. Our results indicate a high radioresistance of Caco-2 in the investigated dose range, and an increased permeability of the tumoral cell layer due to the presence of PBMC. This is found to be correlated with activation of PBMC, inhibiting the apoptotic pathway, with the enhancement of cytokine release and with variation of tight junction

  9. Midazolam sedation increases fluctuation and synchrony of the resting brain BOLD signal.

    PubMed

    Kiviniemi, Vesa J; Haanpää, Hannu; Kantola, Juha-Heikki; Jauhiainen, Jukka; Vainionpää, Vilho; Alahuhta, Seppo; Tervonen, Osmo

    2005-05-01

    The blood oxygen level-dependent (BOLD) magnetic resonance signal of functional brain cortices is dominated by very low frequency (VLF) fluctuations in anesthetized child patients. The temporal synchrony of the BOLD signal is also higher in anesthetized children compared with awake adults. The origin of the synchronous fluctuations can be related to maturation, pathological status or the anesthesia used in the imaging. Two of the three confounding variables (maturation and pathology) were controlled in this study. The effect of midazolam (4+/-0.8 mg) sedation on the BOLD signal was assessed in 12 healthy adults (aged 24+/-1.5 years) at 1.5 T. The VLF fluctuation power and temporal synchrony of the BOLD signal increased significantly after the sedation in the auditory and visual cortices. The fast Fourier transformation power spectral baseline fit parameters of the BOLD signal were also found to change significantly after sedation. It is concluded that the VLF fluctuation and temporal synchrony of the BOLD signal become increased after sedation in functional brain regions.

  10. Supramolecular Nanofibers Enhance Growth Factor Signaling by Increasing Lipid Raft Mobility

    SciTech Connect

    Newcomb, Christina J.; Sur, Shantanu; Lee, Sungsoo S.; Yu, Jeong Min; Zhou, Yan; Snead, Malcolm L.; Stupp, Samuel I.

    2016-04-12

    The nanostructures of self-assembling biomaterials have been previously designed to tune the release of growth factors in order to optimize biological repair and regeneration. We report here on the discovery that weakly cohesive peptide nanostructures in terms of intermolecular hydrogen bonding, when combined with low concentrations of osteogenic growth factor, enhance both BMP-2 and Wnt mediated signaling in myoblasts and bone marrow stromal cells, respectively. Conversely, analogous nanostructures with enhanced levels of internal hydrogen bonding and cohesion lead to an overall reduction in BMP-2 signaling. We propose that the mechanism for enhanced growth factor signaling by the nanostructures is related to their ability to increase diffusion within membrane lipid rafts. The phenomenon reported here could lead to new nanomedicine strategies to mediate growth factor signaling for translational targets.

  11. Consumption of guar gum and retrograded high-amylose corn resistant starch increases IL-10 abundance without affecting pro-inflammatory cytokines in the colon of pigs fed a high-fat diet.

    PubMed

    Fan, M Z; Archbold, T; Lackeyram, D; Liu, Q; Mine, Y; Paliyath, G

    2012-12-01

    Increases in dietary intake of viscous and nonviscous soluble fiber are reported to improve bowel health. However, related biological mechanisms are not very clear. This study was conducted to examine if colonic inflammation would occur in a typical Western diet model and determine if consumption of soluble fiber components would attenuate potential detrimental effects by differentially affecting colonic abundances of anti-inflammatory cytokine IL-10 and 2 pro-inflammatory cytokines tumor necrosis factor-alpha (TNF-α) and IL-6 in pigs fed a high-fat basal diet supplemented, respectively, with 15% viscous soluble fiber guar gum (GG) and 15% nonviscous soluble fiber, that is, retrograded high-amylose corn (Zea mays) resistant starch (RS). A total of 24 Yorkshire growing barrows were assigned into a standard corn and soybean (Glycine max) meal (SBM)-based grower diet as a positive control (PC), an animal protein-based high-fat basal diet as the negative control (NC), and 2 NC basal diets supplemented with 15% GG and 15% RS, respectively, according to a completely randomized block design for 4 wk. Abundance of these cytokines in homogenized and extracted colonic tissue supernatant samples was measured by ELISA. Although colonic IL-10 abundance was lower (P < 0.05) in the corn and SBM-based PC group than that in the high-fat basal NC group, there were no differences (P > 0.05) in colonic abundances of TNF-α and IL-6 between NC and PC groups and among all of the treatment groups. Compared with the NC group, consumption of GG and RS at 15% increased (P < 0.05) colonic IL-10 abundance. Moreover, there was no difference (P > 0.05) in colonic IL-10 abundance between the 15% GG and the 15% RS groups. Thus, consumption of a typical high-fat Western diet did not induce colonic inflammation. Diets supplemented with 15% GG or 15% RS may protect the colon from developing inflammation by enhancing IL-10 abundance.

  12. Increased bone morphogenetic protein signaling contributes to age-related declines in neurogenesis and cognition

    PubMed Central

    Meyers, Emily A.; Gobeske, Kevin T.; Bond, Allison M.; Jarrett, Jennifer C.; Peng, Chian-Yu; Kessler, John A.

    2015-01-01

    Aging is associated with decreased neurogenesis in the hippocampus and diminished hippocampus-dependent cognitive functions. Expression of bone morphogenetic protein 4 (BMP4) increases with age by more than 10-fold in the mouse dentate gyrus while levels of the BMP inhibitor, noggin, decrease. This results in a profound 30-fold increase in phosphorylated-SMAD1/5/8, the effector of canonical BMP signaling. Just as observed in mice, a profound increase in expression of BMP4 is observed in the dentate gyrus of humans with no known cognitive abnormalities. Inhibition of BMP signaling either by overexpression of noggin or transgenic manipulation not only increases neurogenesis in aging mice, but remarkably, is associated with a rescue of cognitive deficits to levels comparable to young mice. Additive benefits are observed when combining inhibition of BMP signaling and environmental enrichment. These findings indicate that increased BMP signaling contributes significantly to impairments in neurogenesis and to cognitive decline associated with aging, and identify this pathway as a potential druggable target for reversing age-related changes in cognition. PMID:26827654

  13. Nandrolone reduces activation of Notch signaling in denervated muscle associated with increased Numb expression.

    PubMed

    Liu, Xin-Hua; Yao, Shen; Qiao, Rui-Fang; Levine, Alice C; Kirschenbaum, Alexander; Pan, Jiangping; Wu, Yong; Qin, Weiping; Bauman, William A; Cardozo, Christopher P

    2011-10-14

    Nandrolone, an anabolic steroid, slows denervation-atrophy in rat muscle. The molecular mechanisms responsible for this effect are not well understood. Androgens and anabolic steroids activate Notch signaling in animal models of aging and thereby mitigate sarcopenia. To explore the molecular mechanisms by which nandrolone prevents denervation-atrophy, we investigated the effects of nandrolone on Notch signaling in denervated rat gastrocnemius muscle. Denervation significantly increased Notch activity reflected by elevated levels of nuclear Notch intracellular domain (NICD) and expression of Hey1 (a Notch target gene). Activation was greatest at 7 and 35 days after denervation but remained present at 56 days after denervation. Activation of Notch in denervated muscle was prevented by nandrolone associated with upregulated expression of Numb mRNA and protein. These data demonstrate that denervation activates Notch signaling, and that nandrolone abrogates this response associated with increased expression of Numb, suggesting a potential mechanism by which nandrolone reduces denervation-atrophy.

  14. Resolvin D1 Increases Mucin Secretion in Cultured Rat Conjunctival Goblet Cells via Multiple Signaling Pathways

    PubMed Central

    Lippestad, Marit; Hodges, Robin R.; Utheim, Tor P.; Serhan, Charles N.; Dartt, Darlene A.

    2017-01-01

    Purpose Goblet cells in the conjunctiva secrete mucin into the tear film protecting the ocular surface. The proresolution mediator resolvin D1 (RvD1) regulates mucin secretion to maintain homeostasis during physiological conditions and in addition, actively terminates inflammation. We determined the signaling mechanisms used by RvD1 in cultured rat conjunctival goblet cells to increase intracellular [Ca2+] ([Ca2+]i) and induce glycoconjugate secretion. Methods Increase in [Ca2+]i were measured using fura 2/AM and glycoconjugate secretion determined using an enzyme-linked lectin assay with the lectin Ulex Europaeus Agglutinin 1. Signaling pathways activated by RvD1 were studied after goblet cells were pretreated with signaling pathway inhibitors before stimulation with RvD1. The results were compared with results when goblet cells were stimulated with RvD1 alone and percent inhibition calculated. Results The increase in [Ca2+]i stimulated by RvD1 was blocked by inhibitors to phospholipases (PL-) -D, -C, -A2, protein kinase C (PKC), extracellular signal-regulated kinases (ERK)1/2 and Ca2+/calmodulin-dependent kinase (Ca2+/CamK). Glycoconjugate secretion was significantly inhibited by PLD, -C, -A2, ERK1/2 and Ca2+/CamK, but not PKC. Conclusions We conclude that RvD1 increases glycoconjugate secretion from goblet cells via multiple signaling pathways including PLC, PLD, and PLA2, as well as their signaling components ERK1/2 and Ca2+/CamK to preserve the mucous layer and maintain homeostasis by protecting the eye from desiccating stress, allergens, and pathogens. PMID:28892824

  15. Increased spontaneous MEG signal diversity for psychoactive doses of ketamine, LSD and psilocybin.

    PubMed

    Schartner, Michael M; Carhart-Harris, Robin L; Barrett, Adam B; Seth, Anil K; Muthukumaraswamy, Suresh D

    2017-04-19

    What is the level of consciousness of the psychedelic state? Empirically, measures of neural signal diversity such as entropy and Lempel-Ziv (LZ) complexity score higher for wakeful rest than for states with lower conscious level like propofol-induced anesthesia. Here we compute these measures for spontaneous magnetoencephalographic (MEG) signals from humans during altered states of consciousness induced by three psychedelic substances: psilocybin, ketamine and LSD. For all three, we find reliably higher spontaneous signal diversity, even when controlling for spectral changes. This increase is most pronounced for the single-channel LZ complexity measure, and hence for temporal, as opposed to spatial, signal diversity. We also uncover selective correlations between changes in signal diversity and phenomenological reports of the intensity of psychedelic experience. This is the first time that these measures have been applied to the psychedelic state and, crucially, that they have yielded values exceeding those of normal waking consciousness. These findings suggest that the sustained occurrence of psychedelic phenomenology constitutes an elevated level of consciousness - as measured by neural signal diversity.

  16. Increased spontaneous MEG signal diversity for psychoactive doses of ketamine, LSD and psilocybin

    PubMed Central

    Schartner, Michael M.; Carhart-Harris, Robin L.; Barrett, Adam B.; Seth, Anil K.; Muthukumaraswamy, Suresh D.

    2017-01-01

    What is the level of consciousness of the psychedelic state? Empirically, measures of neural signal diversity such as entropy and Lempel-Ziv (LZ) complexity score higher for wakeful rest than for states with lower conscious level like propofol-induced anesthesia. Here we compute these measures for spontaneous magnetoencephalographic (MEG) signals from humans during altered states of consciousness induced by three psychedelic substances: psilocybin, ketamine and LSD. For all three, we find reliably higher spontaneous signal diversity, even when controlling for spectral changes. This increase is most pronounced for the single-channel LZ complexity measure, and hence for temporal, as opposed to spatial, signal diversity. We also uncover selective correlations between changes in signal diversity and phenomenological reports of the intensity of psychedelic experience. This is the first time that these measures have been applied to the psychedelic state and, crucially, that they have yielded values exceeding those of normal waking consciousness. These findings suggest that the sustained occurrence of psychedelic phenomenology constitutes an elevated level of consciousness - as measured by neural signal diversity. PMID:28422113

  17. Increased spontaneous MEG signal diversity for psychoactive doses of ketamine, LSD and psilocybin

    NASA Astrophysics Data System (ADS)

    Schartner, Michael M.; Carhart-Harris, Robin L.; Barrett, Adam B.; Seth, Anil K.; Muthukumaraswamy, Suresh D.

    2017-04-01

    What is the level of consciousness of the psychedelic state? Empirically, measures of neural signal diversity such as entropy and Lempel-Ziv (LZ) complexity score higher for wakeful rest than for states with lower conscious level like propofol-induced anesthesia. Here we compute these measures for spontaneous magnetoencephalographic (MEG) signals from humans during altered states of consciousness induced by three psychedelic substances: psilocybin, ketamine and LSD. For all three, we find reliably higher spontaneous signal diversity, even when controlling for spectral changes. This increase is most pronounced for the single-channel LZ complexity measure, and hence for temporal, as opposed to spatial, signal diversity. We also uncover selective correlations between changes in signal diversity and phenomenological reports of the intensity of psychedelic experience. This is the first time that these measures have been applied to the psychedelic state and, crucially, that they have yielded values exceeding those of normal waking consciousness. These findings suggest that the sustained occurrence of psychedelic phenomenology constitutes an elevated level of consciousness - as measured by neural signal diversity.

  18. Dragon enhances BMP signaling and increases transepithelial resistance in kidney epithelial cells.

    PubMed

    Xia, Yin; Babitt, Jodie L; Bouley, Richard; Zhang, Ying; Da Silva, Nicolas; Chen, Shanzhuo; Zhuang, Zhenjie; Samad, Tarek A; Brenner, Gary J; Anderson, Jennifer L; Hong, Charles C; Schneyer, Alan L; Brown, Dennis; Lin, Herbert Y

    2010-04-01

    The neuronal adhesion protein Dragon acts as a bone morphogenetic protein (BMP) coreceptor that enhances BMP signaling. Given the importance of BMP signaling in nephrogenesis and its putative role in the response to injury in the adult kidney, we studied the localization and function of Dragon in the kidney. We observed that Dragon localized predominantly to the apical surfaces of tubular epithelial cells in the thick ascending limbs, distal convoluted tubules, and collecting ducts of mice. Dragon expression was weak in the proximal tubules and glomeruli. In mouse inner medullary collecting duct (mIMCD3) cells, Dragon generated BMP signals in a ligand-dependent manner, and BMP4 is the predominant endogenous ligand for the Dragon coreceptor. In mIMCD3 cells, BMP4 normally signaled through BMPRII, but Dragon enhanced its signaling through the BMP type II receptor ActRIIA. Dragon and BMP4 increased transepithelial resistance (TER) through the Smad1/5/8 pathway. In epithelial cells isolated from the proximal tubule and intercalated cells of collecting ducts, we observed coexpression of ActRIIA, Dragon, and BMP4 but not BMPRII. Taken together, these results suggest that Dragon may enhance BMP signaling in renal tubular epithelial cells and maintain normal renal physiology.

  19. KRIT1 protein depletion modifies endothelial cell behavior via increased vascular endothelial growth factor (VEGF) signaling.

    PubMed

    DiStefano, Peter V; Kuebel, Julia M; Sarelius, Ingrid H; Glading, Angela J

    2014-11-21

    Disruption of endothelial cell-cell contact is a key event in many cardiovascular diseases and a characteristic of pathologically activated vascular endothelium. The CCM (cerebral cavernous malformation) family of proteins (KRIT1 (Krev-interaction trapped 1), PDCD10, and CCM2) are critical regulators of endothelial cell-cell contact and vascular homeostasis. Here we show novel regulation of vascular endothelial growth factor (VEGF) signaling in KRIT1-depleted endothelial cells. Loss of KRIT1 and PDCD10, but not CCM2, increases nuclear β-catenin signaling and up-regulates VEGF-A protein expression. In KRIT1-depleted cells, increased VEGF-A levels led to increased VEGF receptor 2 (VEGFR2) activation and subsequent alteration of cytoskeletal organization, migration, and barrier function and to in vivo endothelial permeability in KRIT1-deficient animals. VEGFR2 activation also increases β-catenin phosphorylation but is only partially responsible for KRIT1 depletion-dependent disruption of cell-cell contacts. Thus, VEGF signaling contributes to modifying endothelial function in KRIT1-deficient cells and microvessel permeability in Krit1(+/-) mice; however, VEGF signaling is likely not the only contributor to disrupted endothelial cell-cell contacts in the absence of KRIT1.

  20. Feedback signals in myelodysplastic syndromes: increased self-renewal of the malignant clone suppresses normal hematopoiesis.

    PubMed

    Walenda, Thomas; Stiehl, Thomas; Braun, Hanna; Fröbel, Julia; Ho, Anthony D; Schroeder, Thomas; Goecke, Tamme W; Rath, Björn; Germing, Ulrich; Marciniak-Czochra, Anna; Wagner, Wolfgang

    2014-04-01

    Myelodysplastic syndromes (MDS) are triggered by an aberrant hematopoietic stem cell (HSC). It is, however, unclear how this clone interferes with physiologic blood formation. In this study, we followed the hypothesis that the MDS clone impinges on feedback signals for self-renewal and differentiation and thereby suppresses normal hematopoiesis. Based on the theory that the MDS clone affects feedback signals for self-renewal and differentiation and hence suppresses normal hematopoiesis, we have developed a mathematical model to simulate different modifications in MDS-initiating cells and systemic feedback signals during disease development. These simulations revealed that the disease initiating cells must have higher self-renewal rates than normal HSCs to outcompete normal hematopoiesis. We assumed that self-renewal is the default pathway of stem and progenitor cells which is down-regulated by an increasing number of primitive cells in the bone marrow niche--including the premature MDS cells. Furthermore, the proliferative signal is up-regulated by cytopenia. Overall, our model is compatible with clinically observed MDS development, even though a single mutation scenario is unlikely for real disease progression which is usually associated with complex clonal hierarchy. For experimental validation of systemic feedback signals, we analyzed the impact of MDS patient derived serum on hematopoietic progenitor cells in vitro: in fact, MDS serum slightly increased proliferation, whereas maintenance of primitive phenotype was reduced. However, MDS serum did not significantly affect colony forming unit (CFU) frequencies indicating that regulation of self-renewal may involve local signals from the niche. Taken together, we suggest that initial mutations in MDS particularly favor aberrant high self-renewal rates. Accumulation of primitive MDS cells in the bone marrow then interferes with feedback signals for normal hematopoiesis--which then results in cytopenia.

  1. Observation of increased ion cyclotron resonance signal duration through electric field perturbations.

    PubMed

    Kaiser, Nathan K; Bruce, James E

    2005-09-15

    Ion motion in Fourier transform ion cyclotron resonance mass spectrometry (FTICR-MS) is complex and the subject of ongoing theoretical and experimental studies. Two predominant pathways for the loss of ICR signals are thought to include damping of cyclotron motion, in which ions lose kinetic energy and radially damp toward the center of the ICR cell, and dephasing of ion coherence, in which ions of like cyclotron frequency become distributed out of phase at similar cyclotron radii. Both mechanisms result in the loss of induced ion image current in FTICR-MS measurements and are normally inseparable during time-domain signal analysis. For conventional ICR measurements which take advantage of ion ensembles, maximization of the ion population size and density can produce the desired effect of increasing phase coherence of ions during cyclotron motion. However, this approach also presents the risk of coalescence of ion packets of similar frequencies. In general, ICR researchers in the past have lacked the tools necessary to distinguish or independently control dephasing and damping mechanisms for ICR signal loss. Nonetheless, the ability to impart greater phase coherence of ions in ICR measurements will allow significant advances in FTICR-MS research by improving the current understanding of ICR signal loss contributions of dephasing and damping of ion ensembles, increasing overall time-domain signal length, and possibly, resulting in more routine ultrahigh resolution measurements. The results presented here demonstrate the ability to employ a high density electron beam to perturb electric fields within the ICR cell during detection of cyclotron motion, in an approach we call electron-promoted ion coherence (EPIC). As such, EPIC reduces ICR signal degradation through loss of phase coherence, and much longer time-domain signals can be obtained. Our results demonstrate that time-domain signals can be extended by more than a factor of 4 with the implementation of EPIC, as

  2. Simulation study on effects of signaling network structure on the developmental increase in complexity

    SciTech Connect

    Keranen, Soile V.E.

    2003-04-02

    The developmental increase in structural complexity in multicellular life forms depends on local, often non-periodic differences in gene expression. These depend on a network of gene-gene interactions coded within the organismal genome. To better understand how genomic information generates complex expression patterns, I have modeled the pattern forming behavior of small artificial genomes in virtual blastoderm embryos. I varied several basic properties of these genomic signaling networks, such as the number of genes, the distributions of positive (inductive) and negative (repressive) interactions, and the strengths of gene-gene interactions, and analyzed their effects on developmental pattern formation. The results show how even simple genomes can generate complex non-periodic patterns under suitable conditions. They also show how the frequency of complex patterns depended on the numbers and relative arrangements of positive and negative interactions. For example, negative co-regulation of signaling pathway components increased the likelihood of (complex) patterns relative to differential negative regulation of the pathway components. Interestingly, neither quantitative differences either in strengths of signaling interactions nor multiple response thresholds to signal concentration (as in morphogen gradients) were essential for formation of multiple, spatially unique cell types. Thus, with combinatorial code of gene regulation and hierarchical signaling interactions, it is theoretically possible to organize metazoan embryogenesis with just a small fraction of the metazoan genome. Because even small networks can generate complex patterns when they contain a suitable set of connections, evolution of metazoan complexity may have depended more on selection for favourable configurations of signaling interactions than on the increase in numbers of regulatory genes.

  3. Activation of inflammatory signaling by lipopolysaccharide produces a prolonged increase of voluntary alcohol intake in mice

    PubMed Central

    Blednov, Y.A.; Benavidez, J.M.; Geil, C.; Perra, S.; Morikawa, H.; Harris, R.A.

    2011-01-01

    Previous studies showed that mice with genetic predisposition for high alcohol consumption as well as human alcoholics show changes in brain expression of genes related to immune signaling. In addition, mutant mice lacking genes related to immune function show decreased alcohol consumption (Blednov et al., in press), suggesting that immune signaling promotes alcohol consumption. To test the possibility that activation of immune signaling will increase alcohol consumption, we treated mice with lipopolysaccaride (LPS; 1 mg/kg, i.p.) and tested alcohol consumption in the continuous two-bottle choice test. To take advantage of the long-lasting activation of brain immune signaling by LPS, we measured drinking beginning one week or one month after LPS treatment and continued the studies for several months. LPS produced persistent increases in alcohol consumption in C57/Bl6 J (B6) inbred mice, FVBxB6F1 and B6xNZBF1 hybrid mice, but not in FVB inbred mice. To determine if this effect of LPS is mediated through binding to TLR4, we tested mice lacking CD14, a key component of TLR4 signaling. These null mutants showed no increase of alcohol intake after treatment with LPS. LPS treatment decreased ethanol-conditioned taste aversion but did not alter ethanol-conditioned place preference (B6xNZBF1 mice). Electro-physiological studies of dopamine neurons in the ventral tegmental area showed that pretreatment of mice with LPS decreased the neuronal firing rate. These results suggest that activation of immune signaling promotes alcohol consumption and alters certain aspects of alcohol reward/aversion. PMID:21266194

  4. Acute disruption of leptin signaling in vivo leads to increased insulin levels and insulin resistance.

    PubMed

    Levi, Jasna; Gray, Sarah L; Speck, Madeleine; Huynh, Frank K; Babich, Sandra L; Gibson, William T; Kieffer, Timothy J

    2011-09-01

    Leptin, an adipocyte-derived hormone, plays an essential role in the maintenance of normal body weight and energy expenditure, as well as glucose homeostasis. Indeed, leptin-deficient ob/ob mice are obese with profound hyperinsulinemia, insulin resistance, and often hyperglycemia. Interestingly, low doses of exogenous leptin can reverse the hyperinsulinemia and hyperglycemia in these animals without altering body weight. The hyperinsulinemia in ob/ob mice may result directly from the absence of leptin signaling in pancreatic β-cells and, in turn, contribute to both obesity and insulin resistance. Here, we acutely attenuated endogenous leptin signaling in normal mice with a polyethylene glycol (PEG)ylated mouse leptin antagonist (PEG-MLA) to determine the contribution of leptin signaling in the regulation of glucose homeostasis. PEG-MLA was either injected or continuously administered via osmotic minipumps for several days, and various metabolic parameters were assessed. PEG-MLA-treated mice had increased fasting and glucose-stimulated plasma insulin levels, decreased whole-body insulin sensitivity, elevated hepatic glucose production, and impaired insulin-mediated suppression of hepatic glucose production. Moreover, PEG-MLA treatment resulted in increased food intake and increased respiratory quotient without significantly altering energy expenditure or body composition as assessed by the lean:lipid ratio. Our findings indicate that alterations in insulin sensitivity occur before changes in the lean:lipid ratio and energy expenditure during the acute disruption of endogenous leptin signaling.

  5. Direct stimulation of bone mass by increased GH signalling in the osteoblasts of Socs2-/- mice.

    PubMed

    Dobie, R; MacRae, V E; Huesa, C; van't Hof, R; Ahmed, S F; Farquharson, C

    2014-10-01

    The suppressor of cytokine signalling (Socs2(-/-))-knockout mouse is characterised by an overgrowth phenotype due to enhanced GH signalling. The objective of this study was to define the Socs2(-/-) bone phenotype and determine whether GH promotes bone mass via IGF1-dependent mechanisms. Despite no elevation in systemic IGF1 levels, increased body weight in 4-week-old Socs2(-/-) mice following GH treatment was associated with increased cortical bone area (Ct.Ar) (P<0.01). Furthermore, detailed bone analysis of male and female juvenile and adult Socs2(-/-) mice revealed an altered cortical and trabecular phenotype consistent with the known anabolic effects of GH. Indeed, male Socs2(-/-) mice had increased Ct.Ar (P<0.05) and thickness associated with increased strength. Despite this, there was no elevation in hepatic Igf1 expression, suggesting that the anabolic bone phenotype was the result of increased local GH action. Mechanistic studies showed that in osteoblasts and bone of Socs2(-/-) mice, STAT5 phosphorylation was significantly increased in response to GH. Conversely, overexpression of SOCS2 decreased GH-induced STAT5 signalling. Although an increase in Igf1 expression was observed in Socs2(-/-) osteoblasts following GH, it was not evident in vivo. Igf1 expression levels were not elevated in response to GH in 4-week-old mice and no alterations in expression was observed in bone samples of 6-week-old Socs2(-/-) mice. These studies emphasise the critical role of SOCS2 in controlling the local GH anabolic bone effects. We provide compelling evidence implicating SOCS2 in the regulation of GH osteoblast signalling and ultimately bone accrual, which maybe via mechanisms that are independent of IGF1 production in vivo.

  6. The Relative Effectiveness of Signaling Systems: Relying on External Items Reduces Signaling Accuracy while Leks Increase Accuracy

    PubMed Central

    Leighton, Gavin M.

    2014-01-01

    Multiple evolutionary phenomena require individual animals to assess conspecifics based on behaviors, morphology, or both. Both behavior and morphology can provide information about individuals and are often used as signals to convey information about quality, motivation, or energetic output. In certain cases, conspecific receivers of this information must rank these signaling individuals based on specific traits. The efficacy of information transfer associated within a signal is likely related to the type of trait used to signal, though few studies have investigated the relative effectiveness of contrasting signaling systems. I present a set of models that represent a large portion of signaling systems and compare them in terms of the ability of receivers to rank signalers accurately. Receivers more accurately assess signalers if the signalers use traits that do not require non-food resources; similarly, receivers more accurately ranked signalers if all the signalers could be observed simultaneously, similar to leks. Surprisingly, I also found that receivers are only slightly better at ranking signaler effort if the effort results in a cumulative structure. This series of findings suggests that receivers may attend to specific traits because the traits provide more information relative to others; and similarly, these results may explain the preponderance of morphological and behavioral display signals. PMID:24626221

  7. Hemocyanins Stimulate Innate Immunity by Inducing Different Temporal Patterns of Proinflammatory Cytokine Expression in Macrophages

    PubMed Central

    Zhong, Ta-Ying; Arancibia, Sergio; Born, Raimundo; Tampe, Ricardo; Villar, Javiera; Del Campo, Miguel; Manubens, Augusto

    2016-01-01

    Hemocyanins induce a potent Th1-dominant immune response with beneficial clinical outcomes when used as a carrier/adjuvant in vaccines and nonspecific immunostimulant in cancer. However, the mechanisms by which hemocyanins trigger innate immune responses, leading to beneficial adaptive immune responses, are unknown. This response is triggered by a proinflammatory signal from various components, of which macrophages are an essential part. To understand how these proteins influence macrophage response, we investigated the effects of mollusks hemocyanins with varying structural and immunological properties, including hemocyanins from Concholepas concholepas, Fissurella latimarginata, and Megathura crenulata (keyhole limpet hemocyanin), on cultures of peritoneal macrophages. Hemocyanins were phagocytosed and slowly processed. Analysis of this process showed differential gene expression along with protein levels of proinflammatory markers, including IL-1β, IL-6, IL-12p40, and TNF-α. An extended expression analysis of 84 cytokines during a 24-h period showed a robust proinflammatory response for F. latimarginata hemocyanin in comparison with keyhole limpet hemocyanin and C. concholepas hemocyanin, which was characterized by an increase in the transcript levels of M1 cytokines involved in leukocyte recruitment. These cytokine genes included chemokines (Cxcl1, Cxcl3, Cxcl5, Ccl2, and Ccl3), ILs (Il1b and Ifng), growth factors (Csf2 and Csf3), and TNF family members (Cd40lg). The protein levels of certain cytokines were increased. However, every hemocyanin maintains downregulated key M2 cytokine genes, including Il4 and Il5. Collectively, our data demonstrate that hemocyanins are able to trigger the release of proinflammatory factors with different patterns of cytokine expression, suggesting differential signaling pathways and transcriptional network mechanisms that lead to the activation of M1-polarized macrophages. PMID:27183578

  8. Dietary intervention in acne: Attenuation of increased mTORC1 signaling promoted by Western diet.

    PubMed

    Melnik, Bodo

    2012-01-01

    The purpose of this paper is to highlight the endocrine signaling of Western diet, a fundamental environmental factor involved in the pathogenesis of epidemic acne. Western nutrition is characterized by high calorie uptake, high glycemic load, high fat and meat intake, as well as increased consumption of insulin- and IGF-1-level elevating dairy proteins. Metabolic signals of Western diet are sensed by the nutrient-sensitive kinase, mammalian target of rapamycin complex 1 (mTORC1), which integrates signals of cellular energy, growth factors (insulin, IGF-1) and protein-derived signals, predominantly leucine, provided in high amounts by milk proteins and meat. mTORC1 activates SREBP, the master transcription factor of lipogenesis. Leucine stimulates mTORC1-SREBP signaling and leucine is directly converted by sebocytes into fatty acids and sterols for sebaceous lipid synthesis. Over-activated mTORC1 increases androgen hormone secretion and most likely amplifies androgen-driven mTORC1 signaling of sebaceous follicles. Testosterone directly activates mTORC1. Future research should investigate the effects of isotretinoin on sebocyte mTORC1 activity. It is conceivable that isotretinoin may downregulate mTORC1 in sebocytes by upregulation of nuclear levels of FoxO1. The role of Western diet in acne can only be fully appreciated when all stimulatory inputs for maximal mTORC1 activation, i.e., glucose, insulin, IGF-1 and leucine, are adequately considered. Epidemic acne has to be recognized as an mTORC1-driven disease of civilization like obesity, type 2 diabetes, cancer and neurodegenerative diseases. These new insights into Western diet-mediated mTORC1-hyperactivity provide a rational basis for dietary intervention in acne by attenuating mTORC1 signaling by reducing (1) total energy intake, (2) hyperglycemic carbohydrates, (3) insulinotropic dairy proteins and (4) leucine-rich meat and dairy proteins. The necessary dietary changes are opposed to the evolution of

  9. In Hyperthermia Increased ERK and WNT Signaling Suppress Colorectal Cancer Cell Growth

    PubMed Central

    Bordonaro, Michael; Shirasawa, Senji; Lazarova, Darina L.

    2016-01-01

    Although neoplastic cells exhibit relatively higher sensitivity to hyperthermia than normal cells, hyperthermia has had variable success as an anti-cancer therapy. This variable outcome might be due to the fact that cancer cells themselves have differential degrees of sensitivity to high temperature. We hypothesized that the varying sensitivity of colorectal cancer (CRC) cells to hyperthermia depends upon the differential induction of survival pathways. Screening of such pathways revealed that Extracellular Signal-Regulated Kinase (ERK) signaling is augmented by hyperthermia, and the extent of this modulation correlates with the mutation status of V-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS). Through clonal growth assays, apoptotic analyses and transcription reporter assays of CRC cells that differ only in KRAS mutation status we established that mutant KRAS cells are more sensitive to hyperthermia, as they exhibit sustained ERK signaling hyperactivation and increased Wingless/Integrated (WNT)/beta-catenin signaling. We propose that whereas increased levels of WNT and ERK signaling and a positive feedback between the two pathways is a major obstacle in anti-cancer therapy today, under hyperthermia the hyperinduction of the pathways and their positive crosstalk contribute to CRC cell death. Ascertaining the causative association between types of mutations and hyperthermia sensitivity may allow for a mutation profile-guided application of hyperthermia as an anti-cancer therapy. Since KRAS and WNT signaling mutations are prevalent in CRC, our results suggest that hyperthermia-based therapy might benefit a significant number, but not all, CRC patients. PMID:27187477

  10. Real Diffusion-Weighted MRI Enabling True Signal Averaging and Increased Diffusion Contrast

    PubMed Central

    Eichner, Cornelius; Cauley, Stephen F; Cohen-Adad, Julien; Möller, Harald E; Turner, Robert; Setsompop, Kawin; Wald, Lawrence L

    2015-01-01

    This project aims to characterize the impact of underlying noise distributions on diffusion-weighted imaging. The noise floor is a well-known problem for traditional magnitude-based diffusion-weighted MRI (dMRI) data, leading to biased diffusion model fits and inaccurate signal averaging. Here, we introduce a total-variation-based algorithm to eliminate shot-to-shot phase variations of complex-valued diffusion data with the intention to extract real-valued dMRI datasets. The obtained real-valued diffusion data are no longer superimposed by a noise floor but instead by a zero-mean Gaussian noise distribution, yielding dMRI data without signal bias. We acquired high-resolution dMRI data with strong diffusion weighting and, thus, low signal-to-noise ratio. Both the extracted real-valued and traditional magnitude data were compared regarding signal averaging, diffusion model fitting and accuracy in resolving crossing fibers. Our results clearly indicate that real-valued diffusion data enables idealized conditions for signal averaging. Furthermore, the proposed method enables unbiased use of widely employed linear least squares estimators for model fitting and demonstrates an increased sensitivity to detect secondary fiber directions with reduced angular error. The use of phase-corrected, real-valued data for dMRI will therefore help to clear the way for more detailed and accurate studies of white matter microstructure and structural connectivity on a fine scale. PMID:26241680

  11. Real diffusion-weighted MRI enabling true signal averaging and increased diffusion contrast.

    PubMed

    Eichner, Cornelius; Cauley, Stephen F; Cohen-Adad, Julien; Möller, Harald E; Turner, Robert; Setsompop, Kawin; Wald, Lawrence L

    2015-11-15

    This project aims to characterize the impact of underlying noise distributions on diffusion-weighted imaging. The noise floor is a well-known problem for traditional magnitude-based diffusion-weighted MRI (dMRI) data, leading to biased diffusion model fits and inaccurate signal averaging. Here, we introduce a total-variation-based algorithm to eliminate shot-to-shot phase variations of complex-valued diffusion data with the intention to extract real-valued dMRI datasets. The obtained real-valued diffusion data are no longer superimposed by a noise floor but instead by a zero-mean Gaussian noise distribution, yielding dMRI data without signal bias. We acquired high-resolution dMRI data with strong diffusion weighting and, thus, low signal-to-noise ratio. Both the extracted real-valued and traditional magnitude data were compared regarding signal averaging, diffusion model fitting and accuracy in resolving crossing fibers. Our results clearly indicate that real-valued diffusion data enables idealized conditions for signal averaging. Furthermore, the proposed method enables unbiased use of widely employed linear least squares estimators for model fitting and demonstrates an increased sensitivity to detect secondary fiber directions with reduced angular error. The use of phase-corrected, real-valued data for dMRI will therefore help to clear the way for more detailed and accurate studies of white matter microstructure and structural connectivity on a fine scale. Copyright © 2015 Elsevier Inc. All rights reserved.

  12. Testosterone increases bioavailability of carotenoids: Insights into the honesty of sexual signaling

    PubMed Central

    Blas, J.; Pérez-Rodríguez, L.; Bortolotti, G. R.; Viñuela, J.; Marchant, T. A.

    2006-01-01

    Androgens and carotenoids play a fundamental role in the expression of secondary sex traits in animals that communicate information on individual quality. In birds, androgens regulate song, aggression, and a variety of sexual ornaments and displays, whereas carotenoids are responsible for the red, yellow, and orange colors of the integument. Parallel, but independent, research lines suggest that the evolutionary stability of each signaling system stems from tradeoffs with immune function: androgens can be immunosuppressive, and carotenoids diverted to coloration prevent their use as immunostimulants. Despite strong similarities in the patterns of sex, age and seasonal variation, social function, and proximate control, there has been little success at integrating potential links between the two signaling systems. These parallel patterns led us to hypothesize that testosterone increases the bioavailability of circulating carotenoids. To test this hypothesis, we manipulated testosterone levels of red-legged partridges Alectoris rufa while monitoring carotenoids, color, and immune function. Testosterone treatment increased the concentration of carotenoids in plasma and liver by >20%. Plasma carotenoids were in turn responsible for individual differences in coloration and immune response. Our results provide experimental evidence for a link between testosterone levels and immunoenhancing carotenoids that (i) reconciles conflicting evidence for the immunosuppressive nature of androgens, (ii) provides physiological grounds for a connection between two of the main signaling systems in animals, (iii) explains how these signaling systems can be evolutionary stable and honest, and (iv) may explain the high prevalence of sexual dimorphism in carotenoid-based coloration in animals. PMID:17121984

  13. Cyclic stretch of Embryonic Cardiomyocytes Increases Proliferation, Growth, and Expression While Repressing Tgf-β Signaling

    PubMed Central

    Banerjee, Indroneal; Carrion, Katrina; Serrano, Ricardo; Dyo, Jeffrey; Sasik, Roman; Lund, Sean; Willems, Erik; Aceves, Seema; Meili, Rudolph; Mercola, Mark; Chen, Ju; Zambon, Alexander; Hardiman, Gary; Doherty, Taylor A; Lange, Stephan; del Álamo, Juan C.; Nigam, Vishal

    2014-01-01

    Perturbed biomechanical stimuli are thought to be critical for the pathogenesis of a number of congenital heart defects, including Hypoplastic Left Heart Syndrome (HLHS). While embryonic cardiomyocytes experience biomechanical stretch every heart beat, their molecular responses to biomechanical stimuli during heart development are poorly understood. We hypothesized that biomechanical stimuli activate specific signaling pathways that impact proliferation, gene expression and myocyte contraction. The objective of this study was to expose embryonic mouse cardiomyocytes (EMCM) to cyclic stretch and examine key molecular and phenotypic responses. Analysis of RNA-Sequencing data demonstrated that gene ontology groups associated with myofibril and cardiac development were significantly modulated. Stretch increased EMCM proliferation, size, cardiac gene expression, and myofibril protein levels. Stretch also repressed several components belonging to the Transforming Growth Factor-β (Tgf-β) signaling pathway. EMCMs undergoing cyclic stretch had decreased Tgf-β expression, protein levels, and signaling. Furthermore, treatment of EMCMs with a Tgf-β inhibitor resulted in increased EMCM size. Functionally, Tgf-β signaling repressed EMCM proliferation and contractile function, as assayed via dynamic monolayer force microscopy (DMFM). Taken together, these data support the hypothesis that biomechanical stimuli play a vital role in normal cardiac development and for cardiac pathology, including HLHS. PMID:25446186

  14. Root jasmonates signaling regulates folivore-induced shoot metabolites and increases Nicotiana attenuata resistance

    PubMed Central

    Fragoso, Variluska; Rothe, Eva; Baldwin, Ian T.; Kim, Sang-Gyu

    2016-01-01

    Summary While JA signaling is widely accepted as mediating plant resistance to herbivores, and the importance of the roots in plant defenses is recently being recognized, the function of root-JA production or perception in aboveground plant defense remains unstudied. To restrain JA impairment to the roots, we micrografted wild type Nicotiana attenuata shoots to the roots of transgenic plants impaired in JA signaling, and evaluated ecological relevant traits under glasshouse and field conditions. Root-JA synthesis, conjugation, and perception are involved in regulating nicotine production in roots. Strikingly, roots regulated leaf JA and ABA levels, which in turn, explain differences in nicotine transport from the roots to the shoot via the transpiration stream. Root-JA signaling also regulates the accumulation of other shoot metabolites; these account for plant resistance against a generalist, Spodoptera littoralis, and a specialist herbivore, Manduca sexta. In N. attenuata’s native habitat, silencing root-JA synthesis increased the shoot damage inflicted by Empoasca leafhoppers, which are able to select natural jasmonate mutants. Silencing JA perception in roots also increased damage by Tupiocoris notatus. Thus, the whole is greater than the sum of its parts: root jasmonate signaling profoundly tailors leaf defense responses to aboveground attack. PMID:24580101

  15. Scopolamine rapidly increases mTORC1 signaling, synaptogenesis, and antidepressant behavioral responses

    PubMed Central

    Voleti, Bhavya; Navarria, Andrea; Liu, Rong-Jian; Banasr, Mounira; Li, Nanxin; Terwilliger, Rose; Sanacora, Gerard; Eid, Tore; Aghajanian, George; Duman, Ronald S.

    2013-01-01

    Background Clinical studies report that scopolamine, an acetylcholine muscarinic receptor antagonist, produces rapid antidepressant effects in depressed patients, but the mechanisms underlying the therapeutic response have not been determined. The present study examines the role of the mammalian target of rapamycin complex 1 (mTORC1) and synaptogenesis, which have been implicated in the rapid actions of NMDA receptor antagonists. Methods The influence of scopolamine on mTORC1 signaling was determined by analysis of the phosphorylated and activated forms of mTORC1 signaling proteins in the prefrontal cortex (PFC). The numbers and function of spine synapses were analyzed by whole cell patch clamp recording and 2-photon image analysis of PFC neurons. The actions of scopolamine were examined in the forced swim test in the absence or presence of selective mTORC1 and AMPA receptor inhibitors. Results The results demonstrate that a single, low dose of scopolamine rapidly increases mTORC1 signaling and the number and function of spine synapses in layer V pyramidal neurons in the PFC. Scopolamine administration also produces an antidepressant response in the forced swim test that is blocked by pretreatment with the mTORC1 inhibitor or by a glutamate AMPA receptor antagonist. Conclusions Taken together, the results demonstrate that the antidepressant actions of scopolamine require mTORC1 signaling and are associated with increased glutamate transmission, and synaptogenesis, similar to NMDA receptor antagonists. These findings provide novel targets for safer and more efficacious rapid acting antidepressant agents. PMID:23751205

  16. Inhibition of apoptosis signal-regulating kinase 1 enhances endochondral bone formation by increasing chondrocyte survival.

    PubMed

    Eaton, G J; Zhang, Q-S; Diallo, C; Matsuzawa, A; Ichijo, H; Steinbeck, M J; Freeman, T A

    2014-11-13

    Endochondral ossification is the result of chondrocyte differentiation, hypertrophy, death and replacement by bone. The careful timing and progression of this process is important for normal skeletal bone growth and development, as well as fracture repair. Apoptosis Signal-Regulating Kinase 1 (ASK1) is a mitogen-activated protein kinase (MAPK), which is activated by reactive oxygen species and other cellular stress events. Activation of ASK1 initiates a signaling cascade known to regulate diverse cellular events including cytokine and growth factor signaling, cell cycle regulation, cellular differentiation, hypertrophy, survival and apoptosis. ASK1 is highly expressed in hypertrophic chondrocytes, but the role of ASK1 in skeletal tissues has not been investigated. Herein, we report that ASK1 knockout (KO) mice display alterations in normal growth plate morphology, which include a shorter proliferative zone and a lengthened hypertrophic zone. These changes in growth plate dynamics result in accelerated long bone mineralization and an increased formation of trabecular bone, which can be attributed to an increased resistance of terminally differentiated chondrocytes to undergo cell death. Interestingly, under normal cell culture conditions, mouse embryonic fibroblasts (MEFs) derived from ASK1 KO mice show no differences in either MAPK signaling or osteogenic or chondrogenic differentiation when compared with wild-type (WT) MEFs. However, when cultured with stress activators, H2O2 or staurosporine, the KO cells show enhanced survival, an associated decrease in the activation of proteins involved in death signaling pathways and a reduction in markers of terminal differentiation. Furthermore, in both WT mice treated with the ASK1 inhibitor, NQDI-1, and ASK1 KO mice endochondral bone formation was increased in an ectopic ossification model. These findings highlight a previously unrealized role for ASK1 in regulating endochondral bone formation. Inhibition of ASK1 has

  17. Inhibition of apoptosis signal-regulating kinase 1 enhances endochondral bone formation by increasing chondrocyte survival

    PubMed Central

    Eaton, G J; Zhang, Q-S; Diallo, C; Matsuzawa, A; Ichijo, H; Steinbeck, M J; Freeman, T A

    2014-01-01

    Endochondral ossification is the result of chondrocyte differentiation, hypertrophy, death and replacement by bone. The careful timing and progression of this process is important for normal skeletal bone growth and development, as well as fracture repair. Apoptosis Signal-Regulating Kinase 1 (ASK1) is a mitogen-activated protein kinase (MAPK), which is activated by reactive oxygen species and other cellular stress events. Activation of ASK1 initiates a signaling cascade known to regulate diverse cellular events including cytokine and growth factor signaling, cell cycle regulation, cellular differentiation, hypertrophy, survival and apoptosis. ASK1 is highly expressed in hypertrophic chondrocytes, but the role of ASK1 in skeletal tissues has not been investigated. Herein, we report that ASK1 knockout (KO) mice display alterations in normal growth plate morphology, which include a shorter proliferative zone and a lengthened hypertrophic zone. These changes in growth plate dynamics result in accelerated long bone mineralization and an increased formation of trabecular bone, which can be attributed to an increased resistance of terminally differentiated chondrocytes to undergo cell death. Interestingly, under normal cell culture conditions, mouse embryonic fibroblasts (MEFs) derived from ASK1 KO mice show no differences in either MAPK signaling or osteogenic or chondrogenic differentiation when compared with wild-type (WT) MEFs. However, when cultured with stress activators, H2O2 or staurosporine, the KO cells show enhanced survival, an associated decrease in the activation of proteins involved in death signaling pathways and a reduction in markers of terminal differentiation. Furthermore, in both WT mice treated with the ASK1 inhibitor, NQDI-1, and ASK1 KO mice endochondral bone formation was increased in an ectopic ossification model. These findings highlight a previously unrealized role for ASK1 in regulating endochondral bone formation. Inhibition of ASK1 has

  18. MyD88-dependent pro-inflammatory cytokine response contributes to lethal toxicity of staphylococcal enterotoxin B in mice.

    PubMed

    Kissner, Teri L; Ruthel, Gordon; Cisney, Emily D; Ulrich, Robert G; Fernandez, Stefan; Saikh, Kamal U

    2011-10-01

    An elevated pro-inflammatory cytokine response is the primary cause of death by toxic shock after exposure to staphylococcal enterotoxin B (SEB). Identifying an intracellular signal mediator that predominantly controls the pro-inflammatory response is important for developing a therapeutic strategy. We examined the role of the signaling adaptor MyD88 in cell culture and in a mouse model of toxic shock. Our results indicated that elevated tumor necrosis factor-α, interferon-γ, interleukin (IL)-1α/β and IL-6 production from mouse spleen cells treated with SEB alone or in combination with lipopolysaccharide (LPS) was regulated by MyD88. Elevated levels of MyD88 protein in spleen cells, as well as in CD11c(+) or Mac3(+) cells, and activation of nuclear factor-κB in spleen cells were observed in mice treated with SEB. An SEB-dose dependent lethality was observed in LPS-potentiated and in D-galactosamine-sensitized mice. D-Galactosamine treatment of spleen cells had no effect in cytokine induction but rather increased the sensitivity to toxic shock in mice. Our results demonstrated an impaired pro-inflammatory cytokine production by spleen cells of MyD88(-/-) mice in response to SEB or SEB plus LPS. Most importantly, MyD88(-/-) mice were resistant to SEB-induced death. These results demonstrate that MyD88-dependent pro-inflammatory signaling is responsible for SEB intoxication. In addition, our studies also demonstrated that LPS potentiation, in comparison to D-galactosamine sensitization, contributes to a stronger SEB-induced lethality. This is due to the pro-inflammatory cytokine response elicited by MyD88 after exposure to SEB and LPS. These findings offer an important insight upon SEB intoxication and subsequent therapy targeting MyD88.

  19. Increasing signal-to-noise ratio of marine seismic data: A case study from offshore Korea

    NASA Astrophysics Data System (ADS)

    Kim, Taeyoun; Jang, Seonghyung

    2016-11-01

    Subsurface imaging is difficult without removing the multiples intrinsic to most marine seismic data. Choosing the right multiple suppression method when working with marine data depends on the type of multiples and sometimes involves trial and error. A major amount of multiple energy in seismic data is related to the large reflectivity of the surface. Surface-related multiple elimination (SRME) is effective for suppressing free-surface-related multiples. Although SRME has some limitations, it is widely used because it requires no assumptions about the subsurface velocities, positions, and reflection coefficients of the reflector causing the multiples. The common reflector surface (CRS) stacking technique uses CRS reflectors rather than common mid-point (CMP) reflectors. It stacks more traces than conventional stacking methods and increases the signal-to-noise ratio. The purpose of this study is to address a process issue for multiple suppression with SRME and Radon filtering, and to increase the signal-to-noise ratio by using CRS stacking on seismic data from the eastern continental margin of Korea. To remove free surface multiples, SRME and Radon filtering are applied to attenuate the interbed multiples. Results obtained using synthetic data and field data show that the combination of SRME and Radon filtering is effective for suppressing free-surface multiples and peg-leg multiples. Applying CRS stacking to seismic data in which multiples have been eliminated increases the signal-to-noise ratio for the area examined, which is being considered for carbon dioxide capture and storage.

  20. Peptide YY signaling in the lateral parabrachial nucleus increases food intake through the Y1 receptor

    PubMed Central

    Golub, Danielle; Hayes, Matthew R.; Grill, Harvey J.

    2015-01-01

    Although central PYY delivery potently increases food intake, the sites of action and mechanisms mediating these hyperphagic effects are not fully understood. The present studies investigate the contribution of lateral parabrachial nucleus (lPBN) PYY-Y receptor signaling to food intake control, as lPBN neurons express Y receptors and receive PYY fibers and are known to integrate circulating and visceral sensory signals to regulate energy balance. Immunohistochemical results identified a subpopulation of gigantocellular reticular nucleus PYY-producing neurons that project monosynaptically to the lPBN, providing an endogenous source of PYY to the lPBN. lPBN microinjection of PYY-(1–36) or PYY-(3–36) markedly increased food intake by increasing meal size. To determine which receptors mediate these behavioral results, we first performed quantitative real-time PCR to examine the relative levels of Y receptor expression in lPBN tissue. Gene expression analyses revealed that, while Y1, Y2, and Y5 receptors are each expressed in lPBN tissue, Y1 receptor mRNA is expressed at fivefold higher levels than the others. Furthermore, behavioral/pharmacological results demonstrated that the hyperphagic effects of PYY-(3–36) were eliminated by lPBN pretreatment with a selective Y1 receptor antagonist. Together, these results highlight the lPBN as a novel site of action for the intake-stimulatory effects of central PYY-Y1 receptor signaling. PMID:26330345

  1. Globular adiponectin induces a pro-inflammatory response in human astrocytic cells

    SciTech Connect

    Wan, Zhongxiao; Mah, Dorrian; Simtchouk, Svetlana; Klegeris, Andis; Little, Jonathan P.

    2014-03-28

    Highlights: • Adiponectin receptors are expressed in human astrocytes. • Globular adiponectin induces secretion of IL-6 and MCP-1 from cultured astrocytes. • Adiponectin may play a pro-inflammatory role in astrocytes. - Abstract: Neuroinflammation, mediated in part by activated brain astrocytes, plays a critical role in the development of neurodegenerative disorders, including Alzheimer’s disease (AD). Adiponectin is the most abundant adipokine secreted from adipose tissue and has been reported to exert both anti- and pro-inflammatory effects in peripheral tissues; however, the effects of adiponectin on astrocytes remain unknown. Shifts in peripheral concentrations of adipokines, including adiponectin, could contribute to the observed link between midlife adiposity and increased AD risk. The aim of the present study was to characterize the effects of globular adiponectin (gAd) on pro-inflammatory cytokine mRNA expression and secretion in human U373 MG astrocytic cells and to explore the potential involvement of nuclear factor (NF)-κB, p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK) and phosphatidylinositide 3-kinases (PI3 K) signaling pathways in these processes. We demonstrated expression of adiponectin receptor 1 (adipoR1) and adipoR2 in U373 MG cells and primary human astrocytes. gAd induced secretion of interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1, and gene expression of IL-6, MCP-1, IL-1β and IL-8 in U373 MG cells. Using specific inhibitors, we found that NF-κB, p38MAPK and ERK1/2 pathways are involved in gAd-induced induction of cytokines with ERK1/2 contributing the most. These findings provide evidence that gAd may induce a pro-inflammatory phenotype in human astrocytes.

  2. Inhibition of neddylation represses lipopolysaccharide-induced proinflammatory cytokine production in macrophage cells.

    PubMed

    Chang, Fang-Mei; Reyna, Sara M; Granados, Jose C; Wei, Sung-Jen; Innis-Whitehouse, Wendy; Maffi, Shivani K; Rodriguez, Edward; Slaga, Thomas J; Short, John D

    2012-10-12

    Cullin-RING E3 ligases (CRLs) are a class of ubiquitin ligases that control the proteasomal degradation of numerous target proteins, including IκB, and the activity of these CRLs are positively regulated by conjugation of a Nedd8 polypeptide onto Cullin proteins in a process called neddylation. CRL-mediated degradation of IκB, which normally interacts with and retains NF-κB in the cytoplasm, permits nuclear translocation and transactivation of the NF-κB transcription factor. Neddylation occurs through a multistep enzymatic process involving Nedd8 activating enzymes, and recent studies have shown that the pharmacological agent, MLN4924, can potently inhibit Nedd8 activating enzymes, thereby preventing neddylation of Cullin proteins and preventing the degradation of CRL target proteins. In macrophages, regulation of NF-κB signaling functions as a primary pathway by which infectious agents such as lipopolysaccharides (LPSs) cause the up-regulation of proinflammatory cytokines. Here we have analyzed the effects of MLN4924, and compared the effects of MLN4924 with a known anti-inflammatory agent (dexamethasone), on certain proinflammatory cytokines (TNF-α and IL-6) and the NF-κB signaling pathway in LPS-stimulated macrophages. We also used siRNA to block neddylation to assess the role of this molecular process during LPS-induced cytokine responsiveness. Our results demonstrate that blocking neddylation, either pharmacologically or using siRNA, abrogates the increase in certain proinflammatory cytokines secreted from macrophages in response to LPS. In addition, we have shown that MLN4924 and dexamethasone inhibit LPS-induced cytokine up-regulation at the transcriptional level, albeit through different molecular mechanisms. Thus, neddylation represents a novel molecular process in macrophages that can be targeted to prevent and/or treat the LPS-induced up-regulation of proinflammatory cytokines and the disease processes associated with their up-regulation.

  3. Andes Hantavirus-Infection of a 3D Human Lung Tissue Model Reveals a Late Peak in Progeny Virus Production Followed by Increased Levels of Proinflammatory Cytokines and VEGF-A.

    PubMed

    Sundström, Karin B; Nguyen Hoang, Anh Thu; Gupta, Shawon; Ahlm, Clas; Svensson, Mattias; Klingström, Jonas

    2016-01-01

    Andes virus (ANDV) causes hantavirus pulmonary syndrome (HPS), a severe acute disease with a 40% case fatality rate. Humans are infected via inhalation, and the lungs are severely affected during HPS, but little is known regarding the effects of ANDV-infection of the lung. Using a 3-dimensional air-exposed organotypic human lung tissue model, we analyzed progeny virus production and cytokine-responses after ANDV-infection. After a 7-10 day period of low progeny virus production, a sudden peak in progeny virus levels was observed during approximately one week. This peak in ANDV-production coincided in time with activation of innate immune responses, as shown by induction of type I and III interferons and ISG56. After the peak in ANDV production a low, but stable, level of ANDV progeny was observed until 39 days after infection. Compared to uninfected models, ANDV caused long-term elevated levels of eotaxin-1, IL-6, IL-8, IP-10, and VEGF-A that peaked 20-25 days after infection, i.e., after the observed peak in progeny virus production. Notably, eotaxin-1 was only detected in supernatants from infected models. In conclusion, these findings suggest that ANDV replication in lung tissue elicits a late proinflammatory immune response with possible long-term effects on the local lung cytokine milieu. The change from an innate to a proinflammatory response might be important for the transition from initial asymptomatic infection to severe clinical disease, HPS.

  4. Increased arterial smooth muscle Ca2+ signaling, vasoconstriction, and myogenic reactivity in Milan hypertensive rats

    PubMed Central

    Linde, Cristina I.; Karashima, Eiji; Raina, Hema; Zulian, Alessandra; Wier, Withrow G.; Hamlyn, John M.; Ferrari, Patrizia; Blaustein, Mordecai P.

    2012-01-01

    The Milan hypertensive strain (MHS) rats are a genetic model of hypertension with adducin gene polymorphisms linked to enhanced renal tubular Na+ reabsorption. Recently we demonstrated that Ca2+ signaling is augmented in freshly isolated mesenteric artery myocytes from MHS rats. This is associated with greatly enhanced expression of Na+/Ca2+ exchanger-1 (NCX1), C-type transient receptor potential (TRPC6) protein, and sarco(endo)plasmic reticulum Ca2+-ATPase (SERCA2) compared with arteries from Milan normotensive strain (MNS) rats. Here, we test the hypothesis that the enhanced Ca2+ signaling in MHS arterial smooth muscle is directly reflected in augmented vasoconstriction [myogenic and phenylephrine (PE)-evoked responses] in isolated mesenteric small arteries. Systolic blood pressure was higher in MHS (145 ± 1 mmHg) than in MNS (112 ± 1 mmHg; P < 0.001; n = 16 each) rats. Pressurized mesenteric resistance arteries from MHS rats had significantly augmented myogenic tone and reactivity and enhanced constriction to low-dose (1–100 nM) PE. Isolated MHS arterial myocytes exhibited approximately twofold increased peak Ca2+ signals in response to 5 μM PE or ATP in the absence and presence of extracellular Ca2+. These augmented responses are consistent with increased vasoconstrictor-evoked sarcoplasmic reticulum (SR) Ca2+ release and increased Ca2+ entry, respectively. The increased SR Ca2+ release correlates with a doubling of inositol 1,4,5-trisphosphate receptor type 1 and tripling of SERCA2 expression. Pressurized MHS arteries also exhibited a ∼70% increase in 100 nM ouabain-induced vasoconstriction compared with MNS arteries. These functional alterations reveal that, in a genetic model of hypertension linked to renal dysfunction, multiple mechanisms within the arterial myocytes contribute to enhanced Ca2+ signaling and myogenic and vasoconstrictor-induced arterial constriction. MHS rats have elevated plasma levels of endogenous ouabain, which may initiate the

  5. Chemical diplomacy in male tilapia: urinary signal increases sex hormone and decreases aggression.

    PubMed

    Saraiva, João L; Keller-Costa, Tina; Hubbard, Peter C; Rato, Ana; Canário, Adelino V M

    2017-08-09

    Androgens, namely 11-ketotestosterone (11KT), have a central role in male fish reproductive physiology and are thought to be involved in both aggression and social signalling. Aggressive encounters occur frequently in social species, and fights may cause energy depletion, injury and loss of social status. Signalling for social dominance and fighting ability in an agonistic context can minimize these costs. Here, we test the hypothesis of a 'chemical diplomacy' mechanism through urinary signals that avoids aggression and evokes an androgen response in receiver males of Mozambique tilapia (Oreochromis mossambicus). We show a decoupling between aggression and the androgen response; males fighting their mirror image experience an unresolved interaction and a severe drop in urinary 11KT. However, if concurrently exposed to dominant male urine, aggression drops but urinary 11KT levels remain high. Furthermore, 11KT increases in males exposed to dominant male urine in the absence of a visual stimulus. The use of a urinary signal to lower aggression may be an adaptive mechanism to resolve disputes and avoid the costs of fighting. As dominance is linked to nest building and mating with females, the 11KT response of subordinate males suggests chemical eavesdropping, possibly in preparation for parasitic fertilizations.

  6. Floral visual signal increases reproductive success in a sexually deceptive orchid.

    PubMed

    Rakosy, Demetra; Streinzer, Martin; Paulus, Hannes F; Spaethe, Johannes

    2012-12-01

    Sexually deceptive orchids mimic signals emitted by female insects in order to attract mate-searching males. Specific attraction of the targeted pollinator is achieved by sex pheromone mimicry, which constitutes the major attraction channel. In close vicinity of the flower, visual signals may enhance attraction, as was shown recently in the sexually deceptive orchid Ophrys heldreichii. Here, we conducted an in situ manipulation experiment in two populations of O. heldreichii on Crete to investigate whether the presence/absence of the conspicuous pink perianth affects reproductive success in two natural orchid populations. We estimated reproductive success of three treatment groups (with intact, removed and artificial perianth) throughout the flowering period as pollinaria removal (male reproductive success) and massulae deposition (female reproductive success). Reproductive success was significantly increased by the presence of a strong visual signal-the conspicuous perianth-in one study population, however, not in the second, most likely due to the low pollinator abundance in the latter population. This study provides further evidence that the coloured perianth in O. heldreichii is adaptive and thus adds to the olfactory signal to maximise pollinator attraction and reproductive success.

  7. Increasing signal amplitude in fiber Bragg grating detection of Lamb waves using remote bonding.

    PubMed

    Wee, Junghyun; Wells, Brian; Hackney, Drew; Bradford, Philip; Peters, Kara

    2016-07-20

    Networks of fiber Bragg grating (FBG) sensors can serve as structural health monitoring systems for large-scale structures based on the collection of ultrasonic waves. The demodulation of structural Lamb waves using FBG sensors requires a high signal-to-noise ratio because the Lamb waves are of low amplitudes. This paper compares the signal transfer amplitudes between two adhesive mounting configurations for an FBG to detect Lamb waves propagating in an aluminum plate: a directly bonded FBG and a remotely bonded FBG. In the directly bonded FBG case, the Lamb waves create in-plane and out-of-plane displacements, which are transferred through the adhesive bond and detected by the FBG sensor. In the remotely bonded FBG case, the Lamb waves are converted into longitudinal and flexural traveling waves in the optical fiber at the adhesive bond, which propagate through the optical fiber and are detected by the FBG sensor. A theoretical prediction of overall signal attenuation also is performed, which is the combination of material attenuation in the plate and optical fiber and attenuation due to wave spreading in the plate. The experimental results demonstrate that remote bonding of the FBG significantly increases the signal amplitude measured by the FBG.

  8. Light-load resistance exercise increases muscle protein synthesis and hypertrophy signaling in elderly men.

    PubMed

    Agergaard, Jakob; Bülow, Jacob; Jensen, Jacob K; Reitelseder, Søren; Drummond, Micah J; Schjerling, Peter; Scheike, Thomas; Serena, Anja; Holm, Lars

    2017-04-01

    The present study investigated whether well-tolerated light-load resistance exercise (LL-RE) affects skeletal muscle fractional synthetic rate (FSR) and anabolic intracellular signaling as a way to counteract age-related loss of muscle mass. Untrained healthy elderly (>65-yr-old) men were subjected to 13 h of supine rest. After 2.5 h of rest, unilateral LL-RE, consisting of leg extensions (10 sets, 36 repetitions) at 16% of 1 repetition maximum (RM), was conducted. Subsequently, the subjects were randomized to oral intake of 4 g of whey protein per hour (PULSE, n = 10), 28 g of whey protein at 0 h and 12 g of whey protein at 7 h postexercise (BOLUS, n = 10), or 4 g of maltodextrin per hour (placebo, n = 10). Quadriceps muscle biopsies were taken at 0, 3, 7, and 10 h postexercise from the resting and the exercised leg of each subject. Myofibrillar FSR and activity of select targets from the mechanistic target of rapamycin complex 1-signaling cascade were analyzed from the biopsies. LL-RE increased myofibrillar FSR compared with the resting leg throughout the 10-h postexercise period. Phosphorylated (T308) AKT expression increased in the exercised leg immediately after exercise. This increase persisted in the placebo group only. Levels of phosphorylated (T37/46) eukaryotic translation initiation factor 4E-binding protein 1 increased throughout the postexercise period in the exercised leg in the placebo and BOLUS groups and peaked at 7 h. In all three groups, phosphorylated (T56) eukaryotic elongation factor 2 decreased in response to LL-RE. We conclude that resistance exercise at only 16% of 1 RM increased myofibrillar FSR, irrespective of nutrient type and feeding pattern, which indicates an anabolic effect of LL-RE in elderly individuals. This finding was supported by increased signaling for translation initiation and translation elongation in response to LL-RE.

  9. Leptin signaling in the nucleus tractus solitarii increases sympathetic nerve activity to the kidney.

    PubMed

    Mark, Allyn L; Agassandian, Khristofor; Morgan, Donald A; Liu, Xuebo; Cassell, Martin D; Rahmouni, Kamal

    2009-02-01

    The hypothalamic arcuate nucleus was initially regarded as the principal site of leptin action, but there is increasing evidence for functional leptin receptors in extrahypothalamic sites, including the nucleus tractus solitarii (NTS). We demonstrated previously that arcuate injection of leptin increases sympathetic nerve activity (SNA) to brown adipose tissue and kidney. In this study, we tested the hypothesis that leptin signaling in the NTS affects sympathetic neural outflow. Using a stereotaxic device in anesthetized rats, we microinjected leptin (0.25 to 1.00 microg) or saline into the NTS while recording SNA to kidney and brown adipose tissue. Microinjection of leptin into the commissural and medial subnuclei of the caudal NTS at the level of the area postrema in Sprague-Dawley rats produced a dose-related increase in renal SNA (+112+/-15% with leptin 1 microg; n=7; P<0.001) but did not increase SNA to brown adipose tissue (-15+/-12%; P value not significant). This effect depended on intact functional leptin receptors, because it was not observed in Zucker obese rats that have a missense mutation in the leptin receptor. Rostral NTS injection of leptin failed to increase SNA, indicating that leptin signaling in the NTS is probably confined to the caudal NTS at the level of the area postrema. In summary, this study demonstrates that leptin signaling in the caudal NTS increases SNA to the kidney but not to the brown adipose tissue. The study strengthens the concept of a distributed brain network of leptin action and demonstrates that these distributed brain sites can mediate contrasting sympathetic responses to leptin.

  10. Ephedrine hydrochloride protects mice from LPS challenge by promoting IL-10 secretion and inhibiting proinflammatory cytokines.

    PubMed

    Zheng, Yuejuan; Guo, Ziyi; He, Weigang; Yang, Yang; Li, Yuhu; Zheng, Aoxiang; Li, Ping; Zhang, Yan; Ma, Jinzhu; Wen, Mingyue; Yang, Muyi; An, Huazhang; Ji, Guang; Yu, Yizhi

    2012-05-01

    Sepsis and its derivative endotoxic shock are still serious conditions with high mortality in the intensive care unit. The mechanisms that ensure the balance of proinflammatory cytokines and anti-inflammatory cytokine production are of particular importance. As an active α- and β-adrenergic agonist, ephedrine hydrochloride (EH) is a widely used agent for cardiovascular diseases, especially boosting blood pressure. Here we demonstrate that EH increased Toll-like receptor 4 (TLR4)-mediated production of interleukin 10 (IL-10) through p38 MAPK activation. Simultaneously, EH negatively regulated the production of proinflammatory cytokines. Consistently, EH increased lipopolysaccharide (LPS)-induced serum IL-10 and inhibited tumor necrotic factor-α (TNFα) production in vivo. As a result, EH treatment protected mice from endotoxic shock by lethal LPS challenge. In brief, our data demonstrated that EH could contribute to immune homeostasis by balancing the production of proinflammatory cytokines and anti-inflammatory cytokine in TLR4 signaling. This study provides a potential usage of EH in autoimmunologic diseases or other severe inflammations.

  11. Signaling pathways induced by serine proteases to increase intestinal epithelial barrier function

    PubMed Central

    Shang, Judie; Dion, Sébastien P.; Désilets, Antoine; Leduc, Richard

    2017-01-01

    Changes in barrier function of the gastrointestinal tract are thought to contribute to the inflammatory bowel diseases Crohn’s disease and ulcerative colitis. Previous work in our lab demonstrated that apical exposure of intestinal epithelial cell lines to serine proteases results in an increase in transepithelial electrical resistance (TER). However, the underlying mechanisms governing this response are unclear. We aimed to determine the requirement for proteolytic activity, epidermal growth factor receptor (EGFR) activation, and downstream intracellular signaling in initiating and maintaining enhanced barrier function following protease treatment using a canine intestinal epithelial cell line (SCBN). We also examined the role of phosphorylation of myosin regulatory light chain on the serine protease-induced increase in TER through. It was found that proteolytic activity of the serine proteases trypsin and matriptase is required to initiate and maintain the protease-mediated increase in TER. We also show that MMP-independent EGFR activation is essential to the sustained phase of the protease response, and that Src kinases may mediate EGFR transactivation. PI3-K and ERK1/2 signaling were important in reaching a maximal increase in TER following protease stimulation; however, their upstream activators are yet to be determined. CK2 inhibition prevented the increase in TER induced by serine proteases. The bradykinin B(2) receptor was not involved in the change in TER in response to serine proteases, and no change in phosphorylation of MLC was observed after trypsin or matriptase treatment. Taken together, our data show a requirement for ongoing proteolytic activity, EGFR transactivation, as well as downstream PI3-K, ERK1/2, and CK2 signaling in protease-mediated barrier enhancement of intestinal epithelial cells. The pathways mediating enhanced barrier function by proteases may be novel therapeutic targets for intestinal disorders characterized by disrupted

  12. Signaling pathways induced by serine proteases to increase intestinal epithelial barrier function.

    PubMed

    Lahey, Kelcie A; Ronaghan, Natalie J; Shang, Judie; Dion, Sébastien P; Désilets, Antoine; Leduc, Richard; MacNaughton, Wallace K

    2017-01-01

    Changes in barrier function of the gastrointestinal tract are thought to contribute to the inflammatory bowel diseases Crohn's disease and ulcerative colitis. Previous work in our lab demonstrated that apical exposure of intestinal epithelial cell lines to serine proteases results in an increase in transepithelial electrical resistance (TER). However, the underlying mechanisms governing this response are unclear. We aimed to determine the requirement for proteolytic activity, epidermal growth factor receptor (EGFR) activation, and downstream intracellular signaling in initiating and maintaining enhanced barrier function following protease treatment using a canine intestinal epithelial cell line (SCBN). We also examined the role of phosphorylation of myosin regulatory light chain on the serine protease-induced increase in TER through. It was found that proteolytic activity of the serine proteases trypsin and matriptase is required to initiate and maintain the protease-mediated increase in TER. We also show that MMP-independent EGFR activation is essential to the sustained phase of the protease response, and that Src kinases may mediate EGFR transactivation. PI3-K and ERK1/2 signaling were important in reaching a maximal increase in TER following protease stimulation; however, their upstream activators are yet to be determined. CK2 inhibition prevented the increase in TER induced by serine proteases. The bradykinin B(2) receptor was not involved in the change in TER in response to serine proteases, and no change in phosphorylation of MLC was observed after trypsin or matriptase treatment. Taken together, our data show a requirement for ongoing proteolytic activity, EGFR transactivation, as well as downstream PI3-K, ERK1/2, and CK2 signaling in protease-mediated barrier enhancement of intestinal epithelial cells. The pathways mediating enhanced barrier function by proteases may be novel therapeutic targets for intestinal disorders characterized by disrupted epithelial

  13. Increasing 14N NQR signal by 1H-14N level crossing with small magnetic fields.

    PubMed

    Thurber, Kent R; Sauer, Karen L; Buess, Michael L; Klug, Christopher A; Miller, Joel B

    2005-11-01

    NQR detection of materials, such as TNT, is hindered by the low signal-to-noise ratio at low NQR frequencies. Sweeping small (0-26 mT) magnetic fields to shift the (1)H NMR frequency relative to the (14)N NQR frequencies can provide a significant increase of the (14)N NQR signal-to-noise ratio. Three effects of (1)H-(14)N level crossing are demonstrated in diglycine hydrochloride and TNT. These effects are (1) transferring (1)H polarization to one or more of the (14)N transitions, including the use of an adiabatic flip of the (1)H polarization during the field sweep, (2) shortening the effective (14)N T(1) by the interaction of (1)H with the (14)N transitions, (3) "level transfer" effect where the third (14)N (spin 1) energy level or other (14)N sites with different NQR frequency are used as a reservoir of polarization which is transferred to the measured (14)N transition by the (1)H. The (14)N NQR signal-to-noise ratio can be increased by a factor of 2.5 for one (14)N site in diglycine hydrochloride (and 2.2 in TNT), even though the maximum (1)H frequency used in this work, 111 6 kHz, is only 30% larger than the measured (14)N frequencies (834 kHz for diglycine hydrochloride and 843 kHz for TNT).

  14. Kynurenine signaling increases DNA polymerase kappa expression and promotes genomic instability in glioblastoma cells

    PubMed Central

    Bostian, April C.L.; Maddukuri, Leena; Reed, Megan R.; Savenka, Tatsiana; Hartman, Jessica H.; Davis, Lauren; Pouncey, Dakota L.; Miller, Grover P.; Eoff, Robert L.

    2015-01-01

    Over-expression of the translesion synthesis polymerase (TLS pol) hpol κ in glioblastomas has been linked to a poor patient prognosis; however, the mechanism promoting higher expression in these tumors remains unknown. We determined that activation of the aryl hydrocarbon receptor (AhR) pathway in glioblastoma cells leads to increased hpol κ mRNA and protein levels. We blocked nuclear translocation and DNA binding by the AhR in glioblastoma cells using a small-molecule and observed decreased hpol κ expression. Pharmacological inhibition of tryptophan-2,3-dioxygenase (TDO), the enzyme largely responsible for activating the AhR in glioblastomas, led to a decrease in the endogenous AhR agonist kynurenine (Kyn) and a corresponding decrease in hpol κ protein levels. Importantly, we discovered that inhibiting TDO activity, AhR signaling, or suppressing hpol κ expression with RNA interference led to decreased chromosomal damage in glioblastoma cells. Epistasis assays further supported the idea that TDO activity, activation of AhR signaling and the resulting over-expression of hpol κ function primarily in the same pathway to increase endogenous DNA damage. These findings indicate that up-regulation of hpol κ through glioblastoma-specific TDO activity and activation of AhR signaling likely contributes to the high levels of replication stress and genomic instability observed in these tumors. PMID:26651356

  15. Multisegment coloboma in a case of Marfan syndrome: another possible effect of increased TGFβ signaling.

    PubMed

    LeBlanc, Shannon K; Taranath, Deepa; Morris, Scott; Barnett, Christopher P

    2014-02-01

    Colobomata are etiologically heterogeneous and may occur as an isolated defect or as a feature of a variety of single-gene disorders, chromosomal syndromes, or malformation syndromes. Although not classically associated with Marfan syndrome, colobomata have been described in several reports of Marfan syndrome, typically involving the lens and rarely involving other ocular structures. While colobomata of the lens have been described in Marfan syndrome, there are very few reports of coloboma involving other ocular structures. We report a newborn boy presenting with coloboma of the iris, lens, retina, and optic disk who was subsequently diagnosed with Marfan syndrome. Marfan syndrome is a disorder of increased TGFβ signaling, and recent work in the mouse model suggests a role for TGFβ signaling in eye development and coloboma formation, suggesting a causal association between Marfan syndrome and coloboma.

  16. The case for too little melatonin signalling in increased diabetes risk.

    PubMed

    Bonnefond, Amélie; Froguel, Philippe

    2017-05-01

    Genome-wide association studies have detected an association between type 2 diabetes risk and a non-coding SNP located in MTNR1B, the gene encoding melatonin receptor 2 (MT2). Melatonin regulates circadian rhythms and sleep and associates with metabolic disorders. However, the mechanisms underlying these actions are still unclear. Functional genomic, animal and clinical studies have not reached the same conclusions: while some studies have reported that decreased melatonin signalling increases type 2 diabetes risk, others have found the opposite. In this commentary, we have tried to provide an explanation for these contradictions and we suggest how the community may progress to reach a unified picture of the effect of melatonin and its signalling on type 2 diabetes.

  17. Effects of telmisartan on lipid metabolisms and proinflammatory factors secretion of differentiated 3T3-L1 adipocytes.

    PubMed

    Kang, Chen; Yijun, Li; Jingtao, Dou; Changyu, Pan; Wenhua, Yan; Baoan, Wang; Fangling, Ma; Xianling, Wang; Guoqing, Yang; Yiming, Mu; Juming, Lu

    2015-12-01

    To investigate the effect of telmisartan on the lipometabolisms and the proinflammatory factors secreted from 3T3-L1 adipocytes and to explore the possible mechanisms. Telmisartan was applied to interfere with mature 3T3-L1 adipocytes. The culture's free fatty acids, interleukin 6 (IL-6) and tumor necrosis factor α (TNFα) were evaluated. Oil Red O staining was used to determine the adipogenesis of 3T3-L1 adipocytes. (18)F-FDG uptake levels corrected for protein content were determined by cellular radioactivity. The total RNA was isolated for hybridization experimentation in the microarray. Telmisartan reduced lipid storage and increased (18)F-FDG uptake in a dose-dependent manner, reduced the levels of IL-6 and TNFα and increased those of free fatty acids. One hundred and fifty-seven differentially expressed genes were found by microarray. The mitogen-activated protein kinase (MAPK) signaling pathway involved in the secretion of proinflammatory factor and lipid metabolisms was affected by telmisartan. The expression of endothelial nitric oxide synthetase gene 3 (Nos3) and carnitine palmitoyl transferase 1α (CPT1α) was up-regulated by telmisartan. Telmisartan affected lipometabolisms and the proinflammatory factors secreted from adipocytes. Nos3, CPT1α and the MAPK pathway being affected by telmisartan may be the underlying cause of the improvement in lipid metabolisms and secretion of proinflammatory factors of differentiated 3T3-L1 adipocytes. © The Author(s) 2014.

  18. Increasing Turn Signal Use by Drivers Exiting a University Parking Garage: A Comparison of Passive and Mediated Prompting

    ERIC Educational Resources Information Center

    Clayton, Michael; Myers, Emily

    2008-01-01

    The present study attempted to further existing literature on increasing safe driving practices through visual prompts by targeting turn signal use at a 4-way intersection. Drivers exiting a university parking garage were presented with a visual prompt ("Please Signal and Drive Safely") and then observed for turn signal use while entering an…

  19. Mixed lactate and caffeine compound increases satellite cell activity and anabolic signals for muscle hypertrophy.

    PubMed

    Oishi, Yoshimi; Tsukamoto, Hayato; Yokokawa, Takumi; Hirotsu, Keisuke; Shimazu, Mariko; Uchida, Kenji; Tomi, Hironori; Higashida, Kazuhiko; Iwanaka, Nobumasa; Hashimoto, Takeshi

    2015-03-15

    We examined whether a mixed lactate and caffeine compound (LC) could effectively elicit proliferation and differentiation of satellite cells or activate anabolic signals in skeletal muscles. We cultured C2C12 cells with either lactate or LC for 6 h. We found that lactate significantly increased myogenin and follistatin protein levels and phosphorylation of P70S6K while decreasing the levels of myostatin relative to the control. LC significantly increased protein levels of Pax7, MyoD, and Ki67 in addition to myogenin, relative to control. LC also significantly increased follistatin expression relative to control and stimulated phosphorylation of mTOR and P70S6K. In an in vivo study, male F344/DuCrlCrlj rats were assigned to control (Sed, n = 10), exercise (Ex, n = 12), and LC supplementation (LCEx, n = 13) groups. LC was orally administered daily. The LCEx and Ex groups were exercised on a treadmill, running for 30 min at low intensity every other day for 4 wk. The LCEx group experienced a significant increase in the mass of the gastrocnemius (GA) and tibialis anterior (TA) relative to both the Sed and Ex groups. Furthermore, the LCEx group showed a significant increase in the total DNA content of TA compared with the Sed group. The LCEx group experienced a significant increase in myogenin and follistatin expression of GA relative to the Ex group. These results suggest that administration of LC can effectively increase muscle mass concomitant with elevated numbers of myonuclei, even with low-intensity exercise training, via activated satellite cells and anabolic signals.

  20. Multiplane wave imaging increases signal-to-noise ratio in ultrafast ultrasound imaging

    NASA Astrophysics Data System (ADS)

    Tiran, Elodie; Deffieux, Thomas; Correia, Mafalda; Maresca, David; Osmanski, Bruno-Felix; Sieu, Lim-Anna; Bergel, Antoine; Cohen, Ivan; Pernot, Mathieu; Tanter, Mickael

    2015-11-01

    Ultrafast imaging using plane or diverging waves has recently enabled new ultrasound imaging modes with improved sensitivity and very high frame rates. Some of these new imaging modalities include shear wave elastography, ultrafast Doppler, ultrafast contrast-enhanced imaging and functional ultrasound imaging. Even though ultrafast imaging already encounters clinical success, increasing even more its penetration depth and signal-to-noise ratio for dedicated applications would be valuable. Ultrafast imaging relies on the coherent compounding of backscattered echoes resulting from successive tilted plane waves emissions; this produces high-resolution ultrasound images with a trade-off between final frame rate, contrast and resolution. In this work, we introduce multiplane wave imaging, a new method that strongly improves ultrafast images signal-to-noise ratio by virtually increasing the emission signal amplitude without compromising the frame rate. This method relies on the successive transmissions of multiple plane waves with differently coded amplitudes and emission angles in a single transmit event. Data from each single plane wave of increased amplitude can then be obtained, by recombining the received data of successive events with the proper coefficients. The benefits of multiplane wave for B-mode, shear wave elastography and ultrafast Doppler imaging are experimentally demonstrated. Multiplane wave with 4 plane waves emissions yields a 5.8  ±  0.5 dB increase in signal-to-noise ratio and approximately 10 mm in penetration in a calibrated ultrasound phantom (0.7 d MHz-1 cm-1). In shear wave elastography, the same multiplane wave configuration yields a 2.07  ±  0.05 fold reduction of the particle velocity standard deviation and a two-fold reduction of the shear wave velocity maps standard deviation. In functional ultrasound imaging, the mapping of cerebral blood volume results in a 3 to 6 dB increase of the contrast-to-noise ratio in deep

  1. Multiplane wave imaging increases signal-to-noise ratio in ultrafast ultrasound imaging.

    PubMed

    Tiran, Elodie; Deffieux, Thomas; Correia, Mafalda; Maresca, David; Osmanski, Bruno-Felix; Sieu, Lim-Anna; Bergel, Antoine; Cohen, Ivan; Pernot, Mathieu; Tanter, Mickael

    2015-11-07

    Ultrafast imaging using plane or diverging waves has recently enabled new ultrasound imaging modes with improved sensitivity and very high frame rates. Some of these new imaging modalities include shear wave elastography, ultrafast Doppler, ultrafast contrast-enhanced imaging and functional ultrasound imaging. Even though ultrafast imaging already encounters clinical success, increasing even more its penetration depth and signal-to-noise ratio for dedicated applications would be valuable. Ultrafast imaging relies on the coherent compounding of backscattered echoes resulting from successive tilted plane waves emissions; this produces high-resolution ultrasound images with a trade-off between final frame rate, contrast and resolution. In this work, we introduce multiplane wave imaging, a new method that strongly improves ultrafast images signal-to-noise ratio by virtually increasing the emission signal amplitude without compromising the frame rate. This method relies on the successive transmissions of multiple plane waves with differently coded amplitudes and emission angles in a single transmit event. Data from each single plane wave of increased amplitude can then be obtained, by recombining the received data of successive events with the proper coefficients. The benefits of multiplane wave for B-mode, shear wave elastography and ultrafast Doppler imaging are experimentally demonstrated. Multiplane wave with 4 plane waves emissions yields a 5.8  ±  0.5 dB increase in signal-to-noise ratio and approximately 10 mm in penetration in a calibrated ultrasound phantom (0.7 d MHz(-1) cm(-1)). In shear wave elastography, the same multiplane wave configuration yields a 2.07  ±  0.05 fold reduction of the particle velocity standard deviation and a two-fold reduction of the shear wave velocity maps standard deviation. In functional ultrasound imaging, the mapping of cerebral blood volume results in a 3 to 6 dB increase of the contrast-to-noise ratio in deep

  2. Increase of global monsoon area and precipitation under global warming: A robust signal?

    NASA Astrophysics Data System (ADS)

    Hsu, Pang-chi; Li, Tim; Luo, Jing-Jia; Murakami, Hiroyuki; Kitoh, Akio; Zhao, Ming

    2012-03-01

    Monsoons, the most energetic tropical climate system, exert a great social and economic impact upon billions of people around the world. The global monsoon precipitation had an increasing trend over the past three decades. Whether or not this increasing trend will continue in the 21st century is investigated, based on simulations of three high-resolution atmospheric general circulation models that were forced by different future sea surface temperature (SST) warming patterns. The results show that the global monsoon area, precipitation and intensity all increase consistently among the model projections. This indicates that the strengthened global monsoon is a robust signal across the models and SST patterns explored here. The increase of the global monsoon precipitation is attributed to the increases of moisture convergence and surface evaporation. The former is caused by the increase of atmospheric water vapor and the latter is due to the increase of SST. The effect of the moisture and evaporation increase is offset to a certain extent by the weakening of the monsoon circulation.

  3. Stacked phased array coils for increasing the signal-to-noise ratio in magnetic resonance imaging.

    PubMed

    Dandan Liang; Hon Tat Hui; Tat Soon Yeo; Bing Keong Li

    2013-02-01

    A new concept of using a stacked phased coil array to increase the signal-to-circuit noise ratio (SCNR) in magnetic resonance imaging (MRI) is introduced. Unlike conventional phased coil arrays, the proposed stacked phased coil array is constructed by stacking the coil elements closely together in the vertical direction. Through a proper combination of the coil terminal voltages, the SCNR is shown to increase with the square root of the number of coil elements. A prototype two-element array is constructed and an experimental method is designed to determine the combiner coefficients in a simulated MRI electromagnetic field environment. The experimental results show that the mutual coupling effect among the array coils can be totally removed and the combiner output voltage increases with the number of coil elements. This demonstrates the feasibility of the proposed method.

  4. Blocking Hedgehog release from pancreatic cancer cells increases paracrine signaling potency.

    PubMed

    Damhofer, Helene; Veenstra, Veronique L; Tol, Johanna A M G; van Laarhoven, Hanneke W M; Medema, Jan Paul; Bijlsma, Maarten F

    2015-01-01

    Members of the Hedgehog (Hh) family of morphogens play crucial roles in development but are also involved in the progression of certain types of cancer. Despite being synthesized as hydrophobic dually lipid-modified molecules, and thus being strongly membrane-associated, Hh ligands are able to spread through tissues and act on target cells several cell diameters away. Various mechanisms that mediate Hh release have been discussed in recent years; however, little is known about dispersion of this ligand from cancer cells. Using co-culture models in conjunction with a newly developed reporter system, we were able to show that different members of the ADAM family of metalloproteinases strongly contribute to the release of endogenous bioactive Hh from pancreatic cancer cells, but that this solubilization decreases the potency of cancer cells to signal to adjacent stromal cells in direct co-culture models. These findings imply that under certain conditions, cancer-cell-tethered Hh molecules are the more potent signaling activators and that retaining Hh on the surface of cancer cells can unexpectedly increase the effective signaling range of this ligand, depending on tissue context.

  5. Anabolic steroids activate calcineurin-NFAT signaling and thereby increase myotube size and reduce denervation atrophy.

    PubMed

    Qin, Weiping; Pan, Jiangping; Wu, Yong; Bauman, William A; Cardozo, Christopher

    2015-01-05

    Anabolic androgens have been shown to reduce muscle loss due to immobilization, paralysis and many other medical conditions, but the molecular basis for these actions is poorly understood. We have recently demonstrated that nandrolone, a synthetic androgen, slows muscle atrophy after nerve transection associated with down-regulation of regulator of calcineurin 2 (RCAN2), a calcineurin inhibitor, suggesting a possible role of calcineurin-NFAT signaling. To test this possibility, rat gastrocnemius muscle was analyzed at 56 days after denervation. In denervated muscle, calcineurin activity declined and NFATc4 was excluded from the nucleus and these effects were reversed by nandrolone. Similarly, nandrolone increased calcineurin activity and nuclear NFATc4 levels in cultured L6 myotubes. Nandrolone also induced cell hypertrophy that was blocked by cyclosporin A or overexpression of RCAN2. Finally protection against denervation atrophy by nandrolone in rats was blocked by cyclosporin A. These results demonstrate for the first time that nandrolone activates calcineurin-NFAT signaling, and that such signaling is important in nandrolone-induced cell hypertrophy and protection against paralysis-induced muscle atrophy.

  6. Brain-computer interfaces increase whole-brain signal to noise.

    PubMed

    Papageorgiou, T Dorina; Lisinski, Jonathan M; McHenry, Monica A; White, Jason P; LaConte, Stephen M

    2013-08-13

    Brain-computer interfaces (BCIs) can convert mental states into signals to drive real-world devices, but it is not known if a given covert task is the same when performed with and without BCI-based control. Using a BCI likely involves additional cognitive processes, such as multitasking, attention, and conflict monitoring. In addition, it is challenging to measure the quality of covert task performance. We used whole-brain classifier-based real-time functional MRI to address these issues, because the method provides both classifier-based maps to examine the neural requirements of BCI and classification accuracy to quantify the quality of task performance. Subjects performed a covert counting task at fast and slow rates to control a visual interface. Compared with the same task when viewing but not controlling the interface, we observed that being in control of a BCI improved task classification of fast and slow counting states. Additional BCI control increased subjects' whole-brain signal-to-noise ratio compared with the absence of control. The neural pattern for control consisted of a positive network comprised of dorsal parietal and frontal regions and the anterior insula of the right hemisphere as well as an expansive negative network of regions. These findings suggest that real-time functional MRI can serve as a platform for exploring information processing and frontoparietal and insula network-based regulation of whole-brain task signal-to-noise ratio.

  7. Chitosan drives anti-inflammatory macrophage polarisation and pro-inflammatory dendritic cell stimulation.

    PubMed

    Oliveira, Marta I; Santos, Susana G; Oliveira, Maria J; Torres, Ana L; Barbosa, Mário A

    2012-07-24

    Macrophages and dendritic cells (DC) share the same precursor and play key roles in immunity. Modulation of their behaviour to achieve an optimal host response towards an implanted device is still a challenge. Here we compare the differentiation process and polarisation of these related cell populations and show that they exhibit different responses to chitosan (Ch), with human monocyte-derived macrophages polarising towards an anti-inflammatory phenotype while their DC counterparts display pro-inflammatory features. Macrophages and DC, whose interactions with biomaterials are frequently analysed using fully differentiated cells, were cultured directly on Ch films, rather than exposed to the polymer after complete differentiation. Ch was the sole stimulating factor and activated both macrophages and DC, without leading to significant T cell proliferation. After 10 d on Ch, macrophages significantly down-regulated expression of pro-inflammatory markers, CD86 and MHCII. Production of pro-inflammatory cytokines, particularly TNF-α, decreased with time for cells cultured on Ch, while anti-inflammatory IL-10 and TGF-β1, significantly increased. Altogether, these results suggest an M2c polarisation. Also, macrophage matrix metalloproteinase activity was augmented and cell motility was stimulated by Ch. Conversely, DC significantly enhanced CD86 expression, reduced IL-10 secretion and increased TNF-α and IL-1β levels. Our findings indicate that cells with a common precursor may display different responses, when challenged by the same biomaterial. Moreover, they help to further comprehend macrophage/DC interactions with Ch and the balance between pro- and anti-inflammatory signals associated with implant biomaterials. We propose that an overall pro-inflammatory reaction may hide the expression of anti-inflammatory cytokines, likely relevant for tissue repair/regeneration.

  8. AHNAK deficiency promotes browning and lipolysis in mice via increased responsiveness to β-adrenergic signalling.

    PubMed

    Shin, Jae Hoon; Lee, Seo Hyun; Kim, Yo Na; Kim, Il Yong; Kim, Youn Ju; Kyeong, Dong Soo; Lim, Hee Jung; Cho, Soo Young; Choi, Junhee; Wi, Young Jin; Choi, Jae-Hoon; Yoon, Yeo Sung; Bae, Yun Soo; Seong, Je Kyung

    2016-03-18

    In adipose tissue, agonists of the β3-adrenergic receptor (ADRB3) regulate lipolysis, lipid oxidation, and thermogenesis. The deficiency in the thermogenesis induced by neuroblast differentiation-associated protein AHNAK in white adipose tissue (WAT) of mice fed a high-fat diet suggests that AHNAK may stimulate energy expenditure via development of beige fat. Here, we report that AHNAK deficiency promoted browning and thermogenic gene expression in WAT but not in brown adipose tissue of mice stimulated with the ADRB3 agonist CL-316243. Consistent with the increased thermogenesis, Ahnak(-/-) mice exhibited an increase in energy expenditure, accompanied by elevated mitochondrial biogenesis in WAT depots in response to CL-316243. Additionally, AHNAK-deficient WAT contained more eosinophils and higher levels of type 2 cytokines (IL-4/IL-13) to promote browning of WAT in response to CL-316243. This was associated with enhanced sympathetic tone in the WAT via upregulation of adrb3 and tyrosine hydroxylase (TH) in response to β-adrenergic activation. CL-316243 activated PKA signalling and enhanced lipolysis, as evidenced by increased phosphorylation of hormone-sensitive lipase and release of free glycerol in Ahnak(-/-) mice compared to wild-type mice. Overall, these findings suggest an important role of AHNAK in the regulation of thermogenesis and lipolysis in WAT via β-adrenergic signalling.

  9. AHNAK deficiency promotes browning and lipolysis in mice via increased responsiveness to β-adrenergic signalling

    PubMed Central

    Shin, Jae Hoon; Lee, Seo Hyun; Kim, Yo Na; Kim, Il Yong; Kim, Youn Ju; Kyeong, Dong Soo; Lim, Hee Jung; Cho, Soo Young; Choi, Junhee; Wi, Young Jin; Choi, Jae-Hoon; Yoon, Yeo Sung; Bae, Yun Soo; Seong, Je Kyung

    2016-01-01

    In adipose tissue, agonists of the β3-adrenergic receptor (ADRB3) regulate lipolysis, lipid oxidation, and thermogenesis. The deficiency in the thermogenesis induced by neuroblast differentiation-associated protein AHNAK in white adipose tissue (WAT) of mice fed a high-fat diet suggests that AHNAK may stimulate energy expenditure via development of beige fat. Here, we report that AHNAK deficiency promoted browning and thermogenic gene expression in WAT but not in brown adipose tissue of mice stimulated with the ADRB3 agonist CL-316243. Consistent with the increased thermogenesis, Ahnak−/− mice exhibited an increase in energy expenditure, accompanied by elevated mitochondrial biogenesis in WAT depots in response to CL-316243. Additionally, AHNAK-deficient WAT contained more eosinophils and higher levels of type 2 cytokines (IL-4/IL-13) to promote browning of WAT in response to CL-316243. This was associated with enhanced sympathetic tone in the WAT via upregulation of adrb3 and tyrosine hydroxylase (TH) in response to β-adrenergic activation. CL-316243 activated PKA signalling and enhanced lipolysis, as evidenced by increased phosphorylation of hormone-sensitive lipase and release of free glycerol in Ahnak−/− mice compared to wild-type mice. Overall, these findings suggest an important role of AHNAK in the regulation of thermogenesis and lipolysis in WAT via β-adrenergic signalling. PMID:26987950

  10. With blood in the joint - what happens next? Could activation of a pro-inflammatory signalling axis leading to iRhom2/TNFα-convertase-dependent release of TNFα contribute to haemophilic arthropathy?

    PubMed

    Haxaire, C; Blobel, C P

    2014-05-01

    One of the main complications of haemophilia A is haemophilic arthropathy (HA), a debilitating disease with a significant negative impact on motility and quality of life. Despite major advances in the treatment of haemophilia A, many patients still suffer from HA. We wish to develop new treatments for HA, but must first better understand its causes. Our laboratory studies molecular scissors that release the pro-inflammatory cytokine tumour necrosis factor alpha (TNFα) from cells. TNFα is considered the 'fire alarm' of the body - it helps to fight infections, but can also cause diseases such as inflammatory arthritis. We know that the molecular scissors, called TNFα convertase (TACE), and its newly discovered regulator termed iRhom2 can be rapidly activated by small amounts of cytokines, growth factors, and pro-inflammatory mediators present in the blood. We hypothesize that the rapid activation of TACE could help explain one of the unsolved mysteries regarding the development of HA, which is how even small amounts of blood can provoke a persistent inflammatory response. We propose that once blood enters the joint, iRhom2 and TACE are activated to release TNFα and that this could promote the development of HA in a similar manner to that in which it promotes rheumatoid arthritis (RA). We are currently using immune cells stimulated with blood degradation products, and mouse models of HA, to test this hypothesis. If successful, our study could provide the rationale for testing anti-TNF antibodies, which are already used to treat RA, for the treatment of HA. In addition, they might uncover iRhom2 and TACE as attractive new candidate targets for the treatment of HA. © 2014 John Wiley & Sons Ltd.

  11. TLR4-dependant pro-inflammatory effects of HMGB1 on human adipocyte.

    PubMed

    Gunasekaran, Manoj Kumar; Virama-Latchoumy, Anne-Laurence; Girard, Anne-Claire; Planesse, Cynthia; Guérin-Dubourg, Alexis; Ottosson, Lars; Andersson, Ulf; Césari, Maya; Roche, Régis; Hoareau, Laurence

    2016-01-01

    Chronic low grade inflammation is one of the major metabolic disorders in case of obesity and associated pathologies. By its important secretion function, the role of adipose tissue in this metabolic low grade inflammation is well known. Recently, it was demonstrated that the alarmin high mobility group box protein 1 (HMGB1) is involved in obesity-related pathologies by its increased serum levels in obese compared to normal weight individuals, and by its pro-inflammatory effects. However, the role of HMGB1 on adipocytes inflammation is poorly documented and we propose to investigate this point. Primary culture of human subcutaneous adipocytes were performed from human adipose tissue samples. Cells were treated with recombinant HMGB1 with/without anti-TLR4 antibody and inhibitors of NF-κB and P38 MAPK. Supernatants were collected for IL-6 and MCP-1 ELISA. HMGB1 initiates Toll-like receptor 4 (TLR4)-dependent activation of inflammation through the downstream NF-κB and P38 MAPK signaling pathway to upregulate the secretion of the pro-inflammatory cytokine IL-6. HMGB1 has pro-inflammatory effects on adipocytes. This reinforces the role of TLR4 in adipose tissue inflammation and antagonizing the HMGB1 inflammatory pathway could bring on new therapeutic targets to counteract obesity-associated pathologies.

  12. Metformin in vitro and in vivo increases adenosine signaling in rabbit corpora cavernosa.

    PubMed

    Vignozzi, Linda; Filippi, Sandra; Comeglio, Paolo; Cellai, Ilaria; Morelli, Annamaria; Rastrelli, Giulia; Maneschi, Elena; Mannucci, Edoardo; Maggi, Mario

    2014-07-01

    In subjects with erectile dysfunction responding poorly to sildenafil, metformin was reported to improve erections. The aim of this study is to investigate metformin's mechanism of action on erectile function, particularly focusing on adenosine (ADO) and nitric oxide (NO) signaling in an animal model of high-fat diet (HFD)-induced metabolic syndrome. In vitro contractility studies of penile strips. Penile expression of genes related to ADO or NO signaling was also evaluated. In vitro contractility studies were used to investigate the effect of in vivo and ex vivo metformin administration on ADO- or acetylcholine (Ach)-induced relaxation of penile strips from HFD as compared with animals fed a regular diet (RD). Expression of ADO receptor type 3 (A3 R), ADO deaminase (ADA), AMP deaminase type 1 (AMPD1), and 2 (AMPD2) was decreased in HFD as compared with RD. Accordingly, in HFD the ADO relaxant effect was potentiated as compared with RD (P < 0.02). In vivo metformin treatment in both RD and HFD significantly increased the ADO relaxing effect (P < 0.0001 and P < 0.01, respectively, vs. relative untreated groups) although to a different extent. In fact, the half-maximal inhibitory concentration (IC50 )/IC50 ratio in RD increased fourfold vs. HFD (RD IC50 ratio = 13.75 ± 2.96; HFD IC50 ratio = 2.85 ± 0.52). In corpora cavernosa (CC) from HFD, in vivo metformin (i) normalized A3 R, ADA, and AMPD1; (ii) further decreased AMPD2; (iii) increased dimethylarginine dimethylamino-hydrolase; and (iv) partially restored impaired Ach-induced relaxation. Ex vivo metformin time and dose dependently increased the relaxant effect of ADO in RD. The potentiating effect of metformin on ADO-induced relaxation was significantly reduced by preincubation with NO synthase inhibitor N(ω) -Nitro-L-arginine methyl ester hydrochloride (L-NAME). Interestingly, in vivo testosterone supplementation in HFD rabbits (i) increased penile expression of endothelial NO

  13. PKCδ localization at the membrane increases matrix traction force dependent on PLCγ1/EGFR signaling.

    PubMed

    Jamison, Joshua; Lauffenburger, Douglas; Wang, James C-H; Wells, Alan

    2013-01-01

    During wound healing, fibroblasts initially migrate into the wound bed and later contract the matrix. Relevant mediators of transcellular contractility revealed by systems analyses are protein kinase c delta/myosin light chain-2 (PKCδ/MLC-2). PKCδ is activated by growth factor-driven PLCγ1 hydrolysis of phosphoinositide bisphosphate (PIP2) hydrolysis when it becomes tranlocated to the membrane. This leads to MLC-2 phosphorylation that regulates myosin for contractility. Furthermore, PKCδ n-terminus mediates PKCδ localization to the membrane in relative proximity to PLCγ1 activity. However, the role this localization and the relationship to its activation and signaling of force is not well understood. Therefore, we investigated whether the membrane localization of PKCδ mediates the transcellular contractility of fibroblasts. To determine PKCδ activation in targeted membrane locations in mouse fibroblast cells (NR6-WT), two PKCδ constructs were generated; PKCδ-CaaX with farnesylation moiety targeting PKCδ to the membrane and PKCδ-SaaX a non-targeting control. Increased mean cell force was observed before and during EGF stimulation in fibroblasts expressing membrane-targeted PKCδ (PKCδ-CaaX) when analyzed with 2D cell traction force and 3D compaction of collagen matrix. This effect was reduced in cells deficient in EGFR/PLCy1 signaling. In cells expressing non-membrane targeted PKCδ (PKCδ-SaaX), the cell force exerted outside the ECM (extracellular matrix) was less, but cell motility/speed/persistence was increased after EGF stimulation. Change in cell motility and increased force exertion was also preceded by change in cell morphology. Organization of actin stress fibers was also decreased as a result of increasing membrane targeting of PKCδ. From these results membrane tethering of PKCδ leads to increased force exertion on ECM. Furthermore, our data show PLCγ1 regulation of PKCδ, at least in part, drives transcellular contractility in fibroblasts.

  14. Orexin-1 receptor signaling increases motivation for cocaine-associated cues

    PubMed Central

    Bentzley, Brandon S.; Aston-Jones, Gary

    2015-01-01

    The orexin/hypocretin system is involved in multiple cocaine addiction processes that involve drug-associated environmental cues, including cue-induced reinstatement of extinguished cocaine seeking and expression of conditioned place preference. However, the orexin system does not play a role in several behaviors that are less cue-dependent, such as cocaine-primed reinstatement of extinguished cocaine seeking and low-effort cocaine self-administration. We hypothesized that cocaine-associated cues, but not cocaine alone, engage signaling at orexin-1 receptors (OX1R), and this cue-engaged OX1R signaling increases motivation for cocaine. Motivation for cocaine was measured in Sprague-Dawley rats with behavioral-economic demand curve analysis after pretreatment with the OX1R antagonist SB-334867 (SB) or vehicle with and without light+tone cues. Demand for cocaine was higher when cocaine-associated cues were present, and SB only reduced cocaine demand in the presence of these cues. We then asked if cocaine demand is linked to cued-reinstatement of cocaine seeking, as both procedures are partially driven by cocaine-associated cues in an orexin-dependent manner. SB blocked cue-induced reinstatement behavior, and baseline demand predicted SB efficacy with the largest effect in high demand animals, i.e., animals with the greatest cue-dependent behavior. We conclude that OX1R signaling increases the reinforcing efficacy of cocaine-associated cues but not for cocaine alone. This supports our view that orexin plays a prominent role in the ability of conditioned cues to activate motivational responses. PMID:25754681

  15. Extracellular matrix hyaluronan signals via its CD44 receptor in the increased responsiveness to mechanical stimulation.

    PubMed

    Ferrari, L F; Araldi, D; Bogen, O; Levine, J D

    2016-06-02

    We propose that the extracellular matrix (ECM) signals CD44, a hyaluronan receptor, to increase the responsiveness to mechanical stimulation in the rat hind paw. We report that intradermal injection of hyaluronidase induces mechanical hyperalgesia, that is inhibited by co-administration of a CD44 receptor antagonist, A5G27. The intradermal injection of low (LMWH) but not high (HMWH) molecular weight hyaluronan also induces mechanical hyperalgesia, an effect that was attenuated by pretreatment with HMWH or A5G27. Pretreatment with HMWH also attenuated the hyperalgesia induced by hyaluronidase. Similarly, intradermal injection of A6, a CD44 receptor agonist, produced hyperalgesia that was inhibited by HMWH and A5G27. Inhibitors of protein kinase A (PKA) and Src, but not protein kinase C (PKC), significantly attenuated the hyperalgesia induced by both A6 and LMWH. Finally, to determine if CD44 receptor signaling is involved in a preclinical model of inflammatory pain, we evaluated the effect of A5G27 and HMWH on the mechanical hyperalgesia associated with the inflammation induced by carrageenan. Both A5G27 and HMWH attenuated carrageenan-induced mechanical hyperalgesia. Thus, while LMWH acts at its cognate receptor, CD44, to induce mechanical hyperalgesia, HMWH acts at the same receptor as an antagonist. That the local administration of HMWH or A5G27 inhibits carrageenan-induced hyperalgesia supports the suggestion that carrageenan produces changes in the ECM that contributes to inflammatory pain. These studies define a clinically relevant role for signaling by the hyaluronan receptor, CD44, in increased responsiveness to mechanical stimulation.

  16. Orexin-1 receptor signaling increases motivation for cocaine-associated cues.

    PubMed

    Bentzley, Brandon S; Aston-Jones, Gary

    2015-05-01

    The orexin/hypocretin system is involved in multiple cocaine addiction processes that involve drug-associated environmental cues, including cue-induced reinstatement of extinguished cocaine seeking and expression of conditioned place preference. However, the orexin system does not play a role in several behaviors that are less cue-dependent, such as cocaine-primed reinstatement of extinguished cocaine seeking and low-effort cocaine self-administration. We hypothesized that cocaine-associated cues, but not cocaine alone, engage signaling at orexin-1 receptors (OX1Rs), and this cue-engaged OX1R signaling increases motivation for cocaine. Motivation for cocaine was measured in Sprague-Dawley rats with behavioral-economic demand curve analysis after pretreatment with the OX1R antagonist SB-334867 (SB) or vehicle with and without light + tone cues. Demand for cocaine was higher when cocaine-associated cues were present, and SB only reduced cocaine demand in the presence of these cues. We then investigated whether cocaine demand was linked to the cued reinstatement of cocaine seeking, as both procedures are partially driven by cocaine-associated cues in an orexin-dependent manner. SB blocked cue-induced reinstatement behavior, and baseline demand predicted SB efficacy with the largest effect in high-demand animals, i.e. animals with the greatest cue-dependent behavior. We conclude that OX1R signaling increases the reinforcing efficacy of cocaine-associated cues but not that of cocaine alone. This supports our view that orexin plays a prominent role in the ability of conditioned cues to activate motivational responses. © 2015 Federation of European Neuroscience Societies and John Wiley & Sons Ltd.

  17. Spatial covert attention increases contrast sensitivity across the CSF: support for signal enhancement

    NASA Technical Reports Server (NTRS)

    Carrasco, M.; Penpeci-Talgar, C.; Eckstein, M.

    2000-01-01

    This study is the first to report the benefits of spatial covert attention on contrast sensitivity in a wide range of spatial frequencies when a target alone was presented in the absence of a local post-mask. We used a peripheral precue (a small circle indicating the target location) to explore the effects of covert spatial attention on contrast sensitivity as assessed by orientation discrimination (Experiments 1-4), detection (Experiments 2 and 3) and localization (Experiment 3) tasks. In all four experiments the target (a Gabor patch ranging in spatial frequency from 0.5 to 10 cpd) was presented alone in one of eight possible locations equidistant from fixation. Contrast sensitivity was consistently higher for peripherally- than for neutrally-cued trials, even though we eliminated variables (distracters, global masks, local masks, and location uncertainty) that are known to contribute to an external noise reduction explanation of attention. When observers were presented with vertical and horizontal Gabor patches an external noise reduction signal detection model accounted for the cueing benefit in a discrimination task (Experiment 1). However, such a model could not account for this benefit when location uncertainty was reduced, either by: (a) Increasing overall performance level (Experiment 2); (b) increasing stimulus contrast to enable fine discriminations of slightly tilted suprathreshold stimuli (Experiment 3); and (c) presenting a local post-mask (Experiment 4). Given that attentional benefits occurred under conditions that exclude all variables predicted by the external noise reduction model, these results support the signal enhancement model of attention.

  18. Spatial covert attention increases contrast sensitivity across the CSF: support for signal enhancement

    NASA Technical Reports Server (NTRS)

    Carrasco, M.; Penpeci-Talgar, C.; Eckstein, M.

    2000-01-01

    This study is the first to report the benefits of spatial covert attention on contrast sensitivity in a wide range of spatial frequencies when a target alone was presented in the absence of a local post-mask. We used a peripheral precue (a small circle indicating the target location) to explore the effects of covert spatial attention on contrast sensitivity as assessed by orientation discrimination (Experiments 1-4), detection (Experiments 2 and 3) and localization (Experiment 3) tasks. In all four experiments the target (a Gabor patch ranging in spatial frequency from 0.5 to 10 cpd) was presented alone in one of eight possible locations equidistant from fixation. Contrast sensitivity was consistently higher for peripherally- than for neutrally-cued trials, even though we eliminated variables (distracters, global masks, local masks, and location uncertainty) that are known to contribute to an external noise reduction explanation of attention. When observers were presented with vertical and horizontal Gabor patches an external noise reduction signal detection model accounted for the cueing benefit in a discrimination task (Experiment 1). However, such a model could not account for this benefit when location uncertainty was reduced, either by: (a) Increasing overall performance level (Experiment 2); (b) increasing stimulus contrast to enable fine discriminations of slightly tilted suprathreshold stimuli (Experiment 3); and (c) presenting a local post-mask (Experiment 4). Given that attentional benefits occurred under conditions that exclude all variables predicted by the external noise reduction model, these results support the signal enhancement model of attention.

  19. Nutrient signaling in protein homeostasis: an increase in quantity at the expense of quality.

    PubMed

    Conn, Crystal S; Qian, Shu-Bing

    2013-04-16

    The discovery that rapamycin extends the life span of diverse organisms has triggered many studies aimed at identifying the underlying molecular mechanisms. Mammalian target of rapamycin complex 1 (mTORC1) regulates cell growth and may regulate organismal aging by controlling mRNA translation. However, how inhibiting mTORC1 and decreasing protein synthesis can extend life span remains an unresolved issue. We showed that constitutively active mTORC1 signaling increased general protein synthesis but unexpectedly reduced the quality of newly synthesized polypeptides. We demonstrated that constitutively active mTORC1 decreased translation fidelity by increasing the speed of ribosomal elongation. Conversely, rapamycin treatment restored the quality of newly synthesized polypeptides mainly by slowing the rate of ribosomal elongation. We also found distinct roles for mTORC1 downstream targets in maintaining protein homeostasis. Loss of S6 kinases, but not 4E-BP family proteins, which are both involved in regulation of translation, attenuated the effects of rapamycin on the quality of newly translated proteins. Our results reveal a mechanistic connection between mTORC1 and protein quality, highlighting the central role of nutrient signaling in growth and aging.

  20. Loss of GM-CSF signalling in non-haematopoietic cells increases NSAID ileal injury

    PubMed Central

    Han, Xiaonan; Gilbert, Shila; Groschwitz, Katherine; Hogan, Simon; Jurickova, Ingrid; Trapnell, Bruce; Samson, Charles; Gully, Jonathan

    2014-01-01

    increases NSAID ileal injury; furthermore, GM-CSF signalling in non-haematopoietic cells regulates ileal epithelial homeostasis via the STAT5 pathway. The therapeutic use of GM-CSF may therefore be beneficial in chronic ileitis associated with CD. PMID:20584783

  1. Increased Sucrose Accumulation Regulates Iron-Deficiency Responses by Promoting Auxin Signaling in Arabidopsis Plants.

    PubMed

    Lin, Xian Yong; Ye, Yi Quan; Fan, Shi Kai; Jin, Chong Wei; Zheng, Shao Jian

    2016-02-01

    Previous studies have identified that auxins acts upstream of nitric oxide in regulating iron deficiency responses in roots, but the upstream signaling molecule of auxins remains unknown. In this study, we showed that Fe deficiency increased sucrose (Suc) level in roots of Arabidopsis (Arabidopsis thaliana). Exogenous application of Suc further stimulated Fe deficiency-induced ferric-chelate-reductase (FCR) activity and expression of Fe acquisition-related genes FRO2, IRT1, and FIT in roots. The opposite patterns were observed in the dark treatment. In addition, FCR activity and expression of Fe acquisition-related genes were higher in the Suc high-accumulating transgenic plant 35S::SUC2 but were lower in the Suc low-accumulating mutant suc2-5 compared with wild-type plants under Fe-deficient conditions. Consequently, Fe deficiency tolerance was enhanced in 35S::SUC2 but was compromised in suc2-5. Exogenous Suc also increased root β-glucuronidase (GUS) activity in auxin-inducible reporter DR5-GUS transgenic plants under Fe deficiency. However, exogenous Suc failed to increase FCR activity and expression of Fe acquisition-related genes in the auxin transport-impaired mutants aux1-7 and pin1-1 as well as in the wild-type plants treated with an auxin transport inhibitor under Fe deficiency. In summary, we found that increased Suc accumulation is required for regulating Fe deficiency responses in plants, with auxins acting downstream in transmitting the Fe deficiency signal.

  2. Increased Sucrose Accumulation Regulates Iron-Deficiency Responses by Promoting Auxin Signaling in Arabidopsis Plants1

    PubMed Central

    Lin, Xian Yong; Ye, Yi Quan; Fan, Shi Kai

    2016-01-01

    Previous studies have identified that auxins acts upstream of nitric oxide in regulating iron deficiency responses in roots, but the upstream signaling molecule of auxins remains unknown. In this study, we showed that Fe deficiency increased sucrose (Suc) level in roots of Arabidopsis (Arabidopsis thaliana). Exogenous application of Suc further stimulated Fe deficiency-induced ferric-chelate-reductase (FCR) activity and expression of Fe acquisition-related genes FRO2, IRT1, and FIT in roots. The opposite patterns were observed in the dark treatment. In addition, FCR activity and expression of Fe acquisition-related genes were higher in the Suc high-accumulating transgenic plant 35S::SUC2 but were lower in the Suc low-accumulating mutant suc2-5 compared with wild-type plants under Fe-deficient conditions. Consequently, Fe deficiency tolerance was enhanced in 35S::SUC2 but was compromised in suc2-5. Exogenous Suc also increased root β-glucuronidase (GUS) activity in auxin-inducible reporter DR5-GUS transgenic plants under Fe deficiency. However, exogenous Suc failed to increase FCR activity and expression of Fe acquisition-related genes in the auxin transport-impaired mutants aux1-7 and pin1-1 as well as in the wild-type plants treated with an auxin transport inhibitor under Fe deficiency. In summary, we found that increased Suc accumulation is required for regulating Fe deficiency responses in plants, with auxins acting downstream in transmitting the Fe deficiency signal. PMID:26644507

  3. [Proinflammatory cytokines in patients with pyelonephritis].

    PubMed

    Gaĭseniuk, F Z; Driianskaia, V E; Drannik, G N; Rudenko, M Iu; Lavrenchuk, O V; Stepanova, N M; Stashevskaia, N V; Busygina, Iu S

    2013-09-01

    The antiinflammatory cytokines participate in antiinfective immunity, that is why it is advisable to study their peculiarities in determination of the role in immunologic pathogenesis of pyelonephritis. Of the work is to study the levels of pro-inflammatory blood cytokines in the patients with pyelonephritis (PN), to determine the peculiarities in acute and chronic its course in children and adults. The immuno-enzymic method ELISA and the corresponding test-systems were used to study the levels of cytokines in blood. There were studied the levels of pro-inflammatory cytokines (TNF, MCP and IL-23) in blood serum of patients with acute (APN) and chronic (CPN) pyelonephritis. The analysis showed the reliable increase in levels of all studied findings in both forms of PN--both in all 173 patients and in every group--children (87) and adults (86). The MCP-1 levels in APN are reliably higher than in CPN, while in TNF-b and IL-23--do not differ. The levels of all three cytokines in blood of adults were higher than in children in APN, but TNF--in CPN as well. The high level of TNF, MCP-1 and IL-23 in blood of adults and children confirm their important role both in APN and CPN, but MCP-1 can be considered as a predictor of acute/exacerbation of chronic pyelonephritis. By the findings of the studied cytokines, more expressed immune response was noted in the adults.

  4. Inhibition of central amylin signaling increases food intake and body adiposity in rats.

    PubMed

    Rushing, P A; Hagan, M M; Seeley, R J; Lutz, T A; D'Alessio, D A; Air, E L; Woods, S C

    2001-11-01

    Amylin is a 37-amino acid peptide hormone that is co-secreted with insulin by pancreatic beta cells in response to feeding. We recently reported that amylin potently reduces food intake, body weight, and adiposity when delivered into the 3rd cerebral ventricle (i3vt) of rats. We have now infused i3vt a specific antagonist (AC187) to ascertain the physiological relevance of central amylin in the control of energy balance. After establishing the ability of i3vt AC187 to block the anorexic effect of i3vt amylin, we performed an experiment to examine the impact of acute inhibition of central amylin signaling on feeding. Separate groups (n = 7/group) of ad lib-fed male Long Evans rats were given one bolus i3vt infusion of synthetic cerebrospinal fluid vehicle (CSF) or AC187 (250 or 1000 pmol). Acute infusion of AC187 tended to increase 1-h food intake and significantly elevated 4-h intake. Both the 250 and 1000 pmol doses produced significant increases as compared to CSF. In another experiment designed to tonically inhibit central amylin signaling over an extended period, two other groups of rats (n = 6/group) received continuous i3vt infusion of CSF or 100 pmol/h AC187 over 14 days via implantable osmotic pumps. Rats receiving AC187 ate significantly more food over the 14-day infusion period relative to controls (CSF = 322 +/- 6 g, AC187 = 360 +/- 12 g). Although body weight was not significantly affected, body fat was increased by about 30% in the AC187 rats, with no difference in lean tissue between the groups. Additionally, although fasting plasma glucose did not differ between the CSF and AC187 groups after 14 days of infusion, plasma insulin was significantly elevated in the AC187 rats. In summary, the present results document significant increases of food intake and body adiposity resulting from inhibition of central amylin signaling. They are consistent with our hypothesis that CNS actions of endogenous amylin contribute to the long-term regulation of energy

  5. Schistosome egg antigens elicit a proinflammatory response by trophoblast cells of the human placenta.

    PubMed

    McDonald, Emily A; Kurtis, Jonathan D; Acosta, Luz; Gundogan, Fusun; Sharma, Surendra; Pond-Tor, Sunthorn; Wu, Hai-Wei; Friedman, Jennifer F

    2013-03-01

    Schistosomiasis affects nearly 40 million women of reproductive age. Many of these women are infected while pregnant and lactating. Several studies have demonstrated transplacental trafficking of schistosome antigens; however, little is known regarding how these antigens affect the developing fetus and placenta. To evaluate the impact of schistosomiasis on trophoblasts of the human placenta, we isolated primary trophoblast cells from healthy placentas delivered at term. These trophoblasts were placed in culture and treated with Schistosoma japonicum soluble egg antigens (SEA) or plasma from S. japonicum-infected pregnant women. Outcomes measured included cytokine production and activation of signal transduction pathways. Treatment of primary human trophoblast cells with SEA resulted in upregulation of the proinflammatory cytokines interleukin 6 (IL-6) and IL-8 and the chemokine macrophage inflammatory protein 1α (MIP-1α). Cytokine production in response to SEA was dose dependent and reminiscent of production in response to other proinflammatory stimuli, such as Toll-like receptor 2 (TLR2) and TLR4 agonists. In addition, the signaling pathways extracellular signal-regulated kinase 1/2 (ERK1/2), Jun N-terminal protein kinase (JNK), p38, and NF-κB were all activated by SEA in primary trophoblasts. These effects appeared to be mediated through both carbohydrate and protein epitopes of SEA. Finally, primary trophoblasts cocultured with plasma from S. japonicum-infected pregnant women produced increased levels of IL-8 compared to trophoblasts cocultured with plasma from uninfected pregnant women. We report here a direct impact of SEA on primary human trophoblast cells, which are critical for many aspects of a healthy pregnancy. Our data indicate that schistosome antigens can activate proinflammatory responses in trophoblasts, which might compromise maternal-fetal health in pregnancies complicated by schistosomiasis.

  6. Moderate increases in intracellular calcium activate neuroprotective signals in hippocampal neurons.

    PubMed

    Bickler, P E; Fahlman, C S

    2004-01-01

    Although large increases in neuronal intracellular calcium concentrations ([Ca(2+)](i)) are lethal, moderate increases in [Ca(2+)](i) of 50-200 nM may induce immediate or long-term tolerance of ischemia or other stresses. In neurons in rat hippocampal slice cultures, we determined the relationship between [Ca(2+)](i), cell death, and Ca(2+)-dependent neuroprotective signals before and after a 45 min period of oxygen and glucose deprivation (OGD). Thirty minutes before OGD, [Ca(2+)](i) was increased in CA1 neurons by 40-200 nM with 1 nM-1 microM of a Ca(2+)-selective ionophore (calcimycin or ionomycin-"Ca(2+) preconditioning"). Ca(2+) preconditioning greatly reduced cell death in CA1, CA3 and dentate during the following 7 days, even though [Ca(2+)](i) was similar (approximately 2 microM) in preconditioned and control neurons 1 h after the OGD. When pre-OGD [Ca(2+)](i) was lowered to 25 nM (10 nM ionophore in Ca(2+)-free medium) or increased to 8 microM (10 microM ionophore), more than 90% of neurons died. Increased levels of the anti-apoptotic protein protein kinase B (Akt) and the MAP kinase ERK (p42/44) were present in preconditioned slices after OGD. Reducing Ca(2+) influx, inhibiting calmodulin, and preventing Akt or MAP kinase p42/44 upregulation prevented Ca(2+) preconditioning, supporting a specific role for Ca(2+) in the neuroprotective process. Further, in continuously oxygenated cultured hippocampal/cortical neurons, preconditioning for 30 min with 10 nM ionomycin reduced cell death following a 4 microM increase in [Ca(2+)](i) elicited by 1 microM ionomycin. Thus, a zone of moderately increased [Ca(2+)](i) before a potentially lethal insult promotes cell survival, uncoupling subsequent large increases in [Ca(2+)](i) from initiating cell death processes.

  7. Estradiol inhibits vascular endothelial cells pro-inflammatory activation induced by C-reactive protein.

    PubMed

    Cossette, Émilie; Cloutier, Isabelle; Tardif, Kim; DonPierre, Geneviève; Tanguay, Jean-François

    2013-01-01

    In addition of being an important inflammatory biomarker and a risk factor for cardiovascular disease, much evidence indicates that the C-reactive protein (CRP) contributes to the atherosclerosis development process. This plasmatic protein synthesized by hepatocytes in response to inflammation and tissue injury induces pro-inflammatory molecules' expression by endothelial cells (ECs). Previous studies showed that the 17β-estradiol (E2) has beneficial effects on vascular cells by reducing in vitro pro-inflammatory molecules expressions in EC. Therefore, we hypothesize that E2 blocks or reduces CRP-mediated inflammatory responses by modulating endogenous production of CRP in EC and/or activation mechanisms. Using human aortic ECs (HAECs), we first evaluated CRP production by vascular EC and second demonstrated its self-induction. Indeed, recombinant human CRP stimulation induces a fivefold increase of CRP expression. A 1-h pre-treatment of E2 at a physiologic dose (10(-9 )M) leads to an important decrease of CRP production suggesting a partial blockage of its amplification loop mechanism. Furthermore, in HAEC, E2 reduces the secretion of the most potent agonist of CRP induction, the IL-6, by 21 %. E2 pre-treatment also decreased the expression of pro-inflammatory molecules IL-8, VCAM-1, and ICAM-1 induced by CRP and involved in leukocytes recruitment. In addition, we demonstrated that E2 could restore vascular endothelial growth factor-mediated EC migration response impaired by CRP suggesting another pro-angiogenic property of this hormone. These findings suggest that E2 can interfere with CRP pro-inflammatory effects via activation signals using its rapid, non-genomic pathway that may provide a new mechanism to improve vascular repair.

  8. [Enrichment of extracellular DNA from the cultivation medium of human peripheral blood mononuclears with genomic CpG rich fragments results in increased cell production of IL-6 and TNF-a via activation of the NF-kB signaling pathway].

    PubMed

    Speranskii, A I; Kostyuk, S V; Kalashnikova, E A; Veiko, N N

    2016-03-01

    Previously, it was found that blood plasma extracellular DNA (ecDNA) of patients with rheumatoid arthritis (RA) is enriched with CpG-rich genomic DNA fragments, which contain TLR9 ligands (Veiko et al., 2006). In this study we have demonstrated that ecDNA of a RA patient and model fragments added to a cultivation medium of peripheral blood mononuclear cells (PBMC) of healthy donors stimulate expression of genes for the TLR9-MyD88-NF-kB signaling pathway; this leads to a significant increase in concentrations of the proinflammatory cytokines IL-6 and TNF-a in the cultivation medium. Human genomic DNA non-enriched with the CpG sequences did not stimulate IL-6 and TNF-a synthesis in PBMC. A scheme explaining the potential role ecDNA in the induction and maintenance of increased levels of the proinflammatory cytokines under conditions damaging the human cells has been proposed.

  9. Increased ghrelin signaling prolongs survival in mouse models of human aging through activation of sirtuin1

    PubMed Central

    Fujitsuka, N; Asakawa, A; Morinaga, A; Amitani, M S; Amitani, H; Katsuura, G; Sawada, Y; Sudo, Y; Uezono, Y; Mochiki, E; Sakata, I; Sakai, T; Hanazaki, K; Yada, T; Yakabi, K; Sakuma, E; Ueki, T; Niijima, A; Nakagawa, K; Okubo, N; Takeda, H; Asaka, M; Inui, A

    2016-01-01

    Caloric restriction (CR) is known to retard aging and delay functional decline as well as the onset of diseases in most organisms. Ghrelin is secreted from the stomach in response to CR and regulates energy metabolism. We hypothesized that in CR ghrelin has a role in protecting aging-related diseases. We examined the physiological mechanisms underlying the ghrelin system during the aging process in three mouse strains with different genetic and biochemical backgrounds as animal models of accelerated or normal human aging. The elevated plasma ghrelin concentration was observed in both klotho-deficient and senescence-accelerated mouse prone/8 (SAMP8) mice. Ghrelin treatment failed to stimulate appetite and prolong survival in klotho-deficient mice, suggesting the existence of ghrelin resistance in the process of aging. However, ghrelin antagonist hastened death and ghrelin signaling potentiators rikkunshito and atractylodin ameliorated several age-related diseases with decreased microglial activation in the brain and prolonged survival in klotho-deficient, SAMP8 and aged ICR mice. In vitro experiments, the elevated sirtuin1 (SIRT1) activity and protein expression through the cAMP–CREB pathway was observed after ghrelin and ghrelin potentiator treatment in ghrelin receptor 1a-expressing cells and human umbilical vein endothelial cells. Furthermore, rikkunshito increased hypothalamic SIRT1 activity and SIRT1 protein expression of the heart in the all three mouse models of aging. Pericarditis, myocardial calcification and atrophy of myocardial and muscle fiber were improved by treatment with rikkunshito. Ghrelin signaling may represent one of the mechanisms activated by CR, and potentiating ghrelin signaling may be useful to extend health and lifespan. PMID:26830139

  10. Increase in reactive oxygen species and activation of Akt signaling pathway in neuropathic pain.

    PubMed

    Guedes, Renata P; Araújo, Alex S R; Janner, Daiane; Belló-Klein, Adriane; Ribeiro, Maria Flávia M; Partata, Wania A

    2008-12-01

    Neuropathic pain occurs as a result of peripheral or central nervous system injury. Its pathophysiology involves mainly a central sensitization mechanism that may be correlated to many molecules acting in regions involved in pain processing, such as the spinal cord. It has been demonstrated that reactive oxygen species (ROS) and signaling molecules, such as the serine/threonine protein kinase Akt, are involved in neuropathic pain mechanisms. Thus, the aim of this study was to provide evidence of this relationship. Sciatic nerve transection (SNT) was used to induce neuropathic pain in rats. Western blot analysis of Akt and 4-hydroxy-2-nonenal (HNE)-Michael adducts, and measurement of hydrogen peroxide (H(2)O(2)) in the lumbosacral spinal cord were performed. The main findings were found seven days after SNT, when there was an increase in HNE-Michael adducts formation, total and p-Akt expression, and H(2)O(2) concentration. However, one and 15 days after SNT, H(2)O(2) concentration was raised in both sham (animals that were submitted to surgery without nerve injury) and SNT groups, showing the high sensibility of this ROS to nociceptive afferent stimuli, not only to neuropathic pain. p-Akt also increased in sham and SNT groups one day post injury, but at 3 and 7 days the increase occurred exclusively in SNT animals. Thus, there is crosstalk between intracellular signaling pathways and ROS, and these molecules can act as protective agents in acute pain situations or play a role in the development of chronic pain states.

  11. Angiotensin II type 1a receptor signalling directly contributes to the increased arrhythmogenicity in cardiac hypertrophy

    PubMed Central

    Yasuno, Shinji; Kuwahara, Koichiro; Kinoshita, Hideyuki; Yamada, Chinatsu; Nakagawa, Yasuaki; Usami, Satoru; Kuwabara, Yoshihiro; Ueshima, Kenji; Harada, Masaki; Nishikimi, Toshio; Nakao, Kazuwa

    2013-01-01

    BACKGROUND AND PURPOSE Angiotensin II has been implicated in the development of various cardiovascular ailments, including cardiac hypertrophy and heart failure. The fact that inhibiting its signalling reduced the incidences of both sudden cardiac death and heart failure in several large-scale clinical trials suggests that angiotensin II is involved in increased cardiac arrhythmogenicity during the development of heart failure. However, because angiotensin II also promotes structural remodelling, including cardiomyocyte hypertrophy and cardiac fibrosis, it has been difficult to assess its direct contribution to cardiac arrhythmogenicity independently of the structural effects. EXPERIMENTAL APPROACH We induced cardiac hypertrophy in wild-type (WT) and angiotensin II type 1a receptor knockout (AT1aR-KO) mice by transverse aortic constriction (TAC). The susceptibility to ventricular tachycardia (VT) assessed in an in vivo electrophysiological study was compared in the two genotypes. The effect of acute pharmacological blockade of AT1R on the incidences of arrhythmias was also assessed. KEY RESULTS As described previously, WT and AT1aR-KO mice with TAC developed cardiac hypertrophy to the same degree, but the incidence of VT was much lower in the latter. Moreover, although TAC induced an increase in tyrosine phosphorylation of connexin 43, a critical component of gap junctional channels, and a reduction in ventricular levels of connexin 43 protein in both genotypes, the effect was significantly ameliorated in AT1aR-KO mice. Acute pharmacological blockade of AT1R also reduced the incidence of arrhythmias. CONCLUSIONS AND IMPLICATIONS Our findings demonstrate that AT1aR-mediated signalling makes a direct contribution to the increase in arrhythmogenicity in hypertrophied hearts independently of structural remodelling. PMID:23937445

  12. Exendin-4 Inhibits Hepatic Lipogenesis by Increasing β-Catenin Signaling

    PubMed Central

    Hong, Seok-Woo; Rhee, Eun-Jung; Park, Se Eun; Park, Cheol Young; Oh, Ki Won; Park, Sung Woo; Lee, Won-Young

    2016-01-01

    The aim of this study is to investigate whether the beneficial effect of exendin-4 on hepatic steatosis is mediated by β-catenin signaling. After the HepG2 human hepatoma cells were treated with PA for 24 hours, total triglycerides levels were increased in a dose-dependent manner, and the expression levels of perilipin family members were upregulated in cells treated with 400 μM PA. For our in vitro model of hepatic steatosis, HepG2 cells were treated with 400 μM palmitic acid (PA) in the presence or absence of 100 nM exendin-4 for 24 hours. PA increased the expression of lipogenic genes, such as sterol regulatory element-binding protein 1c (SREBP-1c), peroxisome proliferator-activated receptor gamma (PPARγ), stearoyl-CoA desaturase 1 (SCD1), fatty acid synthase (FAS), and acetyl-CoA carboxylase (ACC) and triglyceride synthesis-involved genes, such as diacylglycerol acyltransferase 1 (DGAT1) and diacylglycerol acyltransferase 2 (DGAT2) in HepG2 cells, whereas exendin-4 treatment significantly prevented the upregulation of SREBP-1c, PPARγ, SCD1, FAS, ACC, DGAT1 and DGAT2. Moreover, exendin-4 treatment increased the expression of phosphorylated glycogen synthase kinase-3 beta (GSK-3β) in the cytosolic fraction and the expression of β-catenin and transcription factor 4 (TCF4) in the nuclear fraction. In addition, siRNA-mediated inhibition of β-catenin upregulated the expression of lipogenic transcription factors. The protective effects of exendin-4 on intracellular triglyceride content and total triglyceride levels were not observed in cells treated with the β-catenin inhibitor IWR-1. These data suggest that exendin-4 treatment improves hepatic steatosis by inhibiting lipogenesis via activation of Wnt/β-catenin signaling. PMID:27907035

  13. Intracrine endothelin signalling evokes IP3-dependent increases in nucleoplasmic Ca2+ in adult cardiac myocytes*

    PubMed Central

    Merlen, Clémence; Farhat, Nada; Luo, Xiaoyan; Chatenet, David; Tadevosyan, Artavazd; Villeneuve, Louis R.; Gillis, Marc-Antoine; Nattel, Stanley; Thorin, Eric; Fournier, Alain; Allen, Bruce G.

    2013-01-01

    Endothelin receptors are present on the nuclear membranes in adult cardiac ventricular myocytes. The objectives of the present study were to determine 1) which endothelin receptor subtype is in cardiac nuclear membranes, 2) if the receptor and ligand traffic from the cell surface to the nucleus, and 3) the effect of increased intracellular ET-1 on nuclear Ca2+ signalling. Confocal microscopy using fluorescently-labeled endothelin analogs confirmed the presence of ETB at the nuclear membrane of rat cardiomyocytes in skinned-cells and isolated nuclei. Furthermore, in both cardiac myocytes and aortic endothelial cells, endocytosed ET:ETB complexes translocated to lysosomes and not the nuclear envelope. Although ETA and ETB can form heterodimers, the presence or absence of ETA did not alter ETB trafficking. Treatment of isolated nuclei with peptide: N-glycosidase F did not alter the electrophoretic mobility of ETB. The absence of N-glycosylation further indicating that these receptors did not originate at the cell surface. Intracellular photolysis of a caged ET-1 analog ([Trp-ODMNB21]ET-1) evoked an increase in nucleoplasmic Ca2+ ([Ca2+]n) that was attenuated by the inositol 1,4,5-trisphosphate receptor inhibitor 2-aminoethoxydiphenyl borate and prevented by pre-treatment with ryanodine. A caged cell-permeable analog of the ETB-selective antagonist IRL-2500 blocked the ability of intracellular cET-1 to increase [Ca2+]n whereas extracellular application of ETA and ETB receptor antagonists did not. These data suggest that 1) the endothelin receptor in the cardiac nuclear membranes is ETB, 2) ETB traffic directly to the nuclear membrane after biosynthesis, 3) exogenous endothelins are not ligands for ETB on nuclear membranes, and 4) ETB associated with the nuclear membranes regulate nuclear Ca2+ signalling. PMID:23756157

  14. MicroRNA-Regulated Proinflammatory Cytokines in Sarcopenia

    PubMed Central

    Fan, Jingjing; Kou, Xianjuan; Yang, Yi; Chen, Ning

    2016-01-01

    Sarcopenia has been defined as the aging-related disease with the declined mass, strength, and function of skeletal muscle, which is the major cause of frailty and falls in elders. The activation of inflammatory signal pathways due to diseases and aging is suggested to reveal the critical impact on sarcopenia. Several proinflammatory cytokines, especially interleukin-6 (IL-6) and tumor necrosis factor-alpha (TNF-α), play crucial roles in modulation of inflammatory signaling pathway during the aging-related loss of skeletal muscle. MicroRNAs (miRNAs) have emerged as the important regulators for the mass and functional maintenance of skeletal muscle through regulating gene expression of proinflammatory cytokines. In this paper, we have systematically discussed regulatory mechanisms of miRNAs for the expression and secretion of inflammatory cytokines during sarcopenia, which will provide some novel targets and therapeutic strategies for controlling aging-related atrophy of skeletal muscle and corresponding chronic inflammatory diseases. PMID:27382188

  15. Sildenafil attenuates LPS-induced pro-inflammatory responses through down-regulation of intracellular ROS-related MAPK/NF-κB signaling pathways in N9 microglia.

    PubMed

    Zhao, Siqi; Zhang, Lijia; Lian, Guoning; Wang, Xiaoxiao; Zhang, Haotian; Yao, Xuechun; Yang, Jingyu; Wu, Chunfu

    2011-04-01

    Excessive activation of microglial cells has been implicated in various neuroinflammation. The present study showed that sildenafil, a PDE5 inhibitor, significantly suppressed NO, interleukin 1β (IL-1β) and tumor necrosis factor α (TNF-α) production induced by LPS in microglial cells through decreasing the protein and/or mRNA expressions of inducible NO synthase (iNOS), IL-1β and TNF-α in a concentration-dependent manner. Sildenafil also blocked IκBα phosphorylation and degradation, inhibited the phosphorylation of mitogen-activated protein kinases (MAPKs), extracellular signal-regulated kinases 1 and 2 (ERK1/2), p38 MAPK, and c-Jun N-terminal kinase (JNK). Moreover, the increase of the expression of gp91phox, a critical and catalytic subunit of NADPH oxidase, and the levels of intracellular reactive oxygen species (iROS) induced by LPS were markedly inhibited by sildenafil. In summary, these data suggest that sildenafil exerts its in vitro anti-inflammatory effect in LPS-activated N9 microglial cells by blocking nuclear factor-κB (NF-κB) and MAPKs activation, which may be partly due to its potent down-regulation of the NADPH-derived iROS production.

  16. Low oxygen tension increased fibronectin fragment induced catabolic activities - response prevented with biomechanical signals

    PubMed Central

    2013-01-01

    Introduction The inherent low oxygen tension in normal cartilage has implications on inflammatory conditions associated with osteoarthritis (OA). Biomechanical signals will additionally contribute to changes in tissue remodelling and influence the inflammatory response. In this study, we investigated the combined effects of oxygen tension and fibronectin fragment (FN-f) on the inflammatory response of chondrocytes subjected to biomechanical signals. Methods Chondrocytes were cultured under free-swelling conditions at 1%, 5% and 21% oxygen tension or subjected to dynamic compression in an ex vivo 3D/bioreactor model with 29 kDa FN-f, interleukin-1beta (IL-1β) and/or the nitric oxide synthase (NOS) inhibitor for 6 and 48 hours. Markers for catabolic activity (NO, PGE2), tissue remodelling (GAG, MMPs) and cytokines (IL-1β, IL-6 and TNFα) were quantified by biochemical assay. Aggrecan, collagen type II, iNOS and COX-2 gene expression were examined by real-time quantitative PCR. Two-way ANOVA and a post hoc Bonferroni-corrected t-test were used to analyse data. Results Both FN-fs and IL-1β increased NO, PGE2 and MMP production (all P < 0.001). FN-f was more active than IL-1β with greater levels of NO observed at 5% than 1% or 21% oxygen tension (P < 0.001). Whilst FN-f reduced GAG synthesis at all oxygen tension, the effect of IL-1β was significant at 1% oxygen tension. In unstrained constructs, treatment with FN-f or IL-1β increased iNOS and COX-2 expression and reduced aggrecan and collagen type II (all P < 0.001). In unstrained constructs, FN-f was more effective than IL-1β at 5% oxygen tension and increased production of NO, PGE2, MMP, IL-1β, IL-6 and TNFα. At 5% and 21% oxygen tension, co-stimulation with compression and the NOS inhibitor abolished fragment or cytokine-induced catabolic activities and restored anabolic response. Conclusions The present findings revealed that FN-fs are more potent than IL-1β in exerting catabolic effects

  17. Kaempferol Isolated from Nelumbo nucifera Inhibits Lipid Accumulation and Increases Fatty Acid Oxidation Signaling in Adipocytes.

    PubMed

    Lee, Bonggi; Kwon, Misung; Choi, Jae Sue; Jeong, Hyoung Oh; Chung, Hae Young; Kim, Hyeung-Rak

    2015-12-01

    Stamens of Nelumbo nucifera Gaertn have been used as a Chinese medicine due to its antioxidant, hypoglycemic, and antiatherogenic activity. However, the effects of kaempferol, a main component of N. nucifera, on obesity are not fully understood. We examined the effect of kaempferol on adipogenesis and fatty acid oxidation signaling pathways in 3T3-L1 adipocytes. Kaempferol reduced cytoplasmic triglyceride (TG) accumulation in dose and time-dependent manners during adipocyte differentiation. Accumulation of TG was rapidly reversed by retrieving kaempferol treatment. Kaempferol broadly decreased mRNA or protein levels of adipogenic transcription factors and their target genes related to lipid accumulation. Kaempferol also suppressed glucose uptake and glucose transporter GLUT4 mRNA expression in adipocytes. Furthermore, protein docking simulation suggests that Kaempferol can directly bind to and activate peroxisome proliferator-activated receptor (PPAR)-α by forming hydrophobic interactions with VAL324, THR279, and LEU321 residues of PPARα. The binding affinity was higher than a well-known PPARα agonist fenofibrate. Consistently, mRNA expression levels of PPARα target genes were increased. Our study indicates while kaempferol inhibits lipogenic transcription factors and lipid accumulation, it may bind to PPARα and stimulate fatty acid oxidation signaling in adipocytes.

  18. Gs-coupled GPCR signalling in AgRP neurons triggers sustained increase in food intake

    PubMed Central

    Nakajima, Ken-ichiro; Cui, Zhenzhong; Li, Chia; Meister, Jaroslawna; Cui, Yinghong; Fu, Ou; Smith, Adam S.; Jain, Shalini; Lowell, Bradford B.; Krashes, Michael J.; Wess, Jürgen

    2016-01-01

    Agouti-related peptide (AgRP) neurons of the hypothalamus play a key role in regulating food intake and body weight, by releasing three different orexigenic molecules: AgRP; GABA; and neuropeptide Y. AgRP neurons express various G protein-coupled receptors (GPCRs) with different coupling properties, including Gs-linked GPCRs. At present, the potential role of Gs-coupled GPCRs in regulating the activity of AgRP neurons remains unknown. Here we show that the activation of Gs-coupled receptors expressed by AgRP neurons leads to a robust and sustained increase in food intake. We also provide detailed mechanistic data linking the stimulation of this class of receptors to the observed feeding phenotype. Moreover, we show that this pathway is clearly distinct from other GPCR signalling cascades that are operative in AgRP neurons. Our data suggest that drugs able to inhibit this signalling pathway may become useful for the treatment of obesity. PMID:26743492

  19. The effects of a synthetic curcuminoid analogue, 2,6-bis-(4-hydroxyl-3-methoxybenzylidine)cyclohexanone on proinflammatory signaling pathways and CLP-induced lethal sepsis in mice.

    PubMed

    Tham, Chau Ling; Lam, Kok Wai; Rajajendram, Revathee; Cheah, Yoke Kqueen; Sulaiman, Mohd Roslan; Lajis, Nordin H; Kim, Min Kyu; Israf, Daud A

    2011-02-10

    We previously showed that 2,6-bis-(4-hydroxyl-3-methoxybenzylidine)cyclohexanone (BHMC), suppressed the synthesis of various proinflammatory mediators. In this study we explain the mechanism of action of BHMC in lipopolysaccharide (LPS)-induced U937 monocytes and further show that BHMC prevents lethality of CLP-induced sepsis. BHMC showed dose-dependent inhibitory effects on p38, JNK and ERK 1/2 activity as determined by inhibition of phosphorylation of downstream transcription factors ATF-2, c-Jun and Elk-1 respectively. Inhibition of these transcription factors subsequently caused total abolishment of AP-1-DNA binding. BHMC inhibited p65 NF-κB nuclear translocation and DNA binding of p65 NF-κB only at the highest concentration used (12.5μM) but failed to alter phosphorylation of JNK, ERK1/2 and STAT-1. Since the inhibition of p38 activity was more pronounced we evaluated the possibility that BHMC may bind to p38. Molecular docking experiments confirmed that BHMC fits well in the highly conserved hydrophobic pocket of p38 MAP kinase. We also show that BHMC was able to improve survival from lethal sepsis in a murine caecal-ligation and puncture (CLP) model.

  20. Acute Nicotine Administration Increases BOLD fMRI Signal in Brain Regions Involved in Reward Signaling and Compulsive Drug Intake in Rats

    PubMed Central

    Alexander, Jon C.; Perez, Pablo D.; Bauzo-Rodriguez, Rayna; Hall, Gabrielle; Klausner, Rachel; Guerra, Valerie; Zeng, Huadong; Igari, Moe; Febo, Marcelo

    2015-01-01

    Background: Acute nicotine administration potentiates brain reward function and enhances motor and cognitive function. These studies investigated which brain areas are being activated by a wide range of doses of nicotine, and if this is diminished by pretreatment with the nonselective nicotinic receptor antagonist mecamylamine. Methods: Drug-induced changes in brain activity were assessed by measuring changes in the blood oxygen level dependent (BOLD) signal using an 11.1-Tesla magnetic resonance scanner. In the first experiment, nicotine naïve rats were mildly anesthetized and the effect of nicotine (0.03–0.6mg/kg) on the BOLD signal was investigated for 10min. In the second experiment, the effect of mecamylamine on nicotine-induced brain activity was investigated. Results: A high dose of nicotine increased the BOLD signal in brain areas implicated in reward signaling, such as the nucleus accumbens shell and the prelimbic area. Nicotine also induced a dose-dependent increase in the BOLD signal in the striato-thalamo-orbitofrontal circuit, which plays a role in compulsive drug intake, and in the insular cortex, which contributes to nicotine craving and relapse. In addition, nicotine induced a large increase in the BOLD signal in motor and somatosensory cortices. Mecamylamine alone did not affect the BOLD signal in most brain areas, but induced a negative BOLD response in cortical areas, including insular, motor, and somatosensory cortices. Pretreatment with mecamylamine completely blocked the nicotine-induced increase in the BOLD signal. Conclusions: These studies demonstrate that acute nicotine administration activates brain areas that play a role in reward signaling, compulsive behavior, and motor and cognitive function. PMID:25552431

  1. Increased hypothalamic GPR54 signaling: a potential mechanism for initiation of puberty in primates.

    PubMed

    Shahab, Muhammad; Mastronardi, Claudio; Seminara, Stephanie B; Crowley, William F; Ojeda, Sergio R; Plant, Tony M

    2005-02-08

    To further study the role of GPR54 signaling in the onset of primate puberty, we used the monkey to examine the ability of kisspeptin-10 to elicit the release of gonadotropin-releasing hormone (GnRH) precociously, and we describe the expression of GPR54 and KiSS-1 in the hypothalamus during the peripubertal period. Agonadal juvenile male monkeys were implanted with a lateral cerebroventricular cannula and a jugular vein catheter. The responsiveness of the juvenile pituitary to endogenous GnRH release was heightened with a chronic pulsatile i.v. infusion of synthetic GnRH before kisspeptin-10 (112-121) injection. Intracerebroventricular (30 microg or 100 microg) or i.v. (100 microg) bolus injections of kisspeptin-10 elicited a robust GnRH discharge, as reflected by luteinizing hormone secretion, which was abolished by pretreatment with a GnRH-receptor antagonist. RNA was isolated from the hypothalamus of agonadal males before (juvenile) and after (pubertal) the pubertal resurgence of pulsatile GnRH release and from juvenile, early pubertal, and midpubertal ovary-intact females. KiSS-1 mRNA levels detected by real-time PCR increased with puberty in both male and female monkeys. In intact females, but not in agonadal males, GPR54 mRNA levels in the hypothalamus increased approximately 3-fold from the juvenile to midpubertal stage. Hybridization histochemistry indicated robust KiSS-1 and GPR54 mRNA expression in the region of the arcuate nucleus. These findings are consistent with the hypothesis that GPR54 signaling by its cognate ligand in the primate hypothalamus may be activated at the end of the juvenile phase of development and may contribute to the pubertal resurgence of pulsatile GnRH release, the central drive for puberty.

  2. Increasing signal processing sophistication in the calculation of the respiratory modulation of the photoplethysmogram (DPOP).

    PubMed

    Addison, Paul S; Wang, Rui; Uribe, Alberto A; Bergese, Sergio D

    2015-06-01

    DPOP (∆POP or Delta-POP) is a non-invasive parameter which measures the strength of respiratory modulations present in the pulse oximetry photoplethysmogram (pleth) waveform. It has been proposed as a non-invasive surrogate parameter for pulse pressure variation (PPV) used in the prediction of the response to volume expansion in hypovolemic patients. Many groups have reported on the DPOP parameter and its correlation with PPV using various semi-automated algorithmic implementations. The study reported here demonstrates the performance gains made by adding increasingly sophisticated signal processing components to a fully automated DPOP algorithm. A DPOP algorithm was coded and its performance systematically enhanced through a series of code module alterations and additions. Each algorithm iteration was tested on data from 20 mechanically ventilated OR patients. Correlation coefficients and ROC curve statistics were computed at each stage. For the purposes of the analysis we split the data into a manually selected 'stable' region subset of the data containing relatively noise free segments and a 'global' set incorporating the whole data record. Performance gains were measured in terms of correlation against PPV measurements in OR patients undergoing controlled mechanical ventilation. Through increasingly advanced pre-processing and post-processing enhancements to the algorithm, the correlation coefficient between DPOP and PPV improved from a baseline value of R = 0.347 to R = 0.852 for the stable data set, and, correspondingly, R = 0.225 to R = 0.728 for the more challenging global data set. Marked gains in algorithm performance are achievable for manually selected stable regions of the signals using relatively simple algorithm enhancements. Significant additional algorithm enhancements, including a correction for low perfusion values, were required before similar gains were realised for the more challenging global data set.

  3. Feeding of Whitefly on Tobacco Decreases Aphid Performance via Increased Salicylate Signaling

    PubMed Central

    Xue, Ming; Zhang, Xiao

    2015-01-01

    Background The feeding of Bemisia tabaci nymphs trigger the SA pathway in some plant species. A previous study showed that B. tabaci nymphs induced defense against aphids (Myzus persicae) in tobacco. However, the mechanism underlying this defense response is not well understood. Methodology/Principal Findings Here, the effect of activating the SA signaling pathway in tobacco plants through B. tabaci nymph infestation on subsequent M. persicae colonization is investigated. Performance assays showed that B. tabaci nymphs pre-infestation significantly reduced M. persicae survival and fecundity systemically in wild-type (WT) but not salicylate-deficient (NahG) plants compared with respective control. However, pre-infestation had no obvious local effects on subsequent M. persicae in either WT or NahG tobacco. SA quantification results indicated that the highest accumulation of SA was induced by B. tabaci nymphs in WT plants after 15 days of infestation. These levels were 8.45- and 6.14-fold higher in the local and systemic leaves, respectively, than in controls. Meanwhile, no significant changes of SA levels were detected in NahG plants. Further, biochemical analysis of defense enzymes polyphenol oxidase (PPO), peroxidase (POD), β-1,3-glucanase, and chitinase demonstrated that B. tabaci nymph infestation increased these enzymes’ activity locally and systemically in WT plants, and there was more chitinase and β-1, 3-glucanase activity systemically than locally, which was opposite to the changing trends of PPO. However, B. tabaci nymph infestation caused no obvious increase in enzyme activity in any NahG plants except POD. Conclusions/Significance In conclusion, these results underscore the important role that induction of the SA signaling pathway by B. tabaci nymphs plays in defeating aphids. It also indicates that the activity of β-1, 3-glucanase and chitinase may be positively correlated with resistance to aphids. PMID:26381273

  4. IL-6 trans-signaling increases expression of airways disease genes in airway smooth muscle.

    PubMed

    Robinson, Mac B; Deshpande, Deepak A; Chou, Jeffery; Cui, Wei; Smith, Shelly; Langefeld, Carl; Hastie, Annette T; Bleecker, Eugene R; Hawkins, Gregory A

    2015-07-15

    Genetic data suggest that IL-6 trans-signaling may have a pathogenic role in the lung; however, the effects of IL-6 trans-signaling on lung effector cells have not been investigated. In this study, human airway smooth muscle (HASM) cells were treated with IL-6 (classical) or IL-6+sIL6R (trans-signaling) for 24 h and gene expression was measured by RNAseq. Intracellular signaling and transcription factor activation were assessed by Western blotting and luciferase assay, respectively. The functional effect of IL-6 trans-signaling was determined by proliferation assay. IL-6 trans-signaling had no effect on phosphoinositide-3 kinase and Erk MAP kinase pathways in HASM cells. Both classical and IL-6 trans-signaling in HASM involves activation of Stat3. However, the kinetics of Stat3 phosphorylation by IL-6 trans-signaling was different than classical IL-6 signaling. This was further reflected in the differential gene expression profile by IL-6 trans-signaling in HASM cells. Under IL-6 trans-signaling conditions 36 genes were upregulated, including PLA2G2A, IL13RA1, MUC1, and SOD2. Four genes, including CCL11, were downregulated at least twofold. The expression of 112 genes was divergent between IL-6 classical and trans-signaling, including the genes HILPDA, NNMT, DAB2, MUC1, WWC1, and VEGFA. Pathway analysis revealed that IL-6 trans-signaling induced expression of genes involved in regulation of airway remodeling, immune response, hypoxia, and glucose metabolism. Treatment of HASM cells with IL-6+sIL6R induced proliferation in a dose-dependent fashion, suggesting a role for IL-6 trans-signaling in asthma pathogenesis. These novel findings demonstrate differential effect of IL-6 trans-signaling on airway cells and identify IL-6 trans-signaling as a potential modifier of airway inflammation and remodeling. Copyright © 2015 the American Physiological Society.

  5. ANGPTL2 increases bone metastasis of breast cancer cells through enhancing CXCR4 signaling.

    PubMed

    Masuda, Tetsuro; Endo, Motoyoshi; Yamamoto, Yutaka; Odagiri, Haruki; Kadomatsu, Tsuyoshi; Nakamura, Takayuki; Tanoue, Hironori; Ito, Hitoshi; Yugami, Masaki; Miyata, Keishi; Morinaga, Jun; Horiguchi, Haruki; Motokawa, Ikuyo; Terada, Kazutoyo; Morioka, Masaki Suimye; Manabe, Ichiro; Iwase, Hirotaka; Mizuta, Hiroshi; Oike, Yuichi

    2015-03-16

    Bone metastasis of breast cancer cells is a major concern, as it causes increased morbidity and mortality in patients. Bone tissue-derived CXCL12 preferentially recruits breast cancer cells expressing CXCR4 to bone metastatic sites. Thus, understanding how CXCR4 expression is regulated in breast cancer cells could suggest approaches to decrease bone metastasis of breast tumor cells. Here, we show that tumor cell-derived angiopoietin-like protein 2 (ANGPTL2) increases responsiveness of breast cancer cells to CXCL12 by promoting up-regulation of CXCR4 in those cells. In addition, we used a xenograft mouse model established by intracardiac injection of tumor cells to show that ANGPTL2 knockdown in breast cancer cells attenuates tumor cell responsiveness to CXCL12 by decreasing CXCR4 expression in those cells, thereby decreasing bone metastasis. Finally, we found that ANGPTL2 and CXCR4 expression levels within primary tumor tissues from breast cancer patients are positively correlated. We conclude that tumor cell-derived ANGPTL2 may increase bone metastasis by enhancing breast tumor cell responsiveness to CXCL12 signaling through up-regulation of tumor cell CXCR4 expression. These findings may suggest novel therapeutic approaches to treat metastatic breast cancer.

  6. Melanocortin 3 Receptor Signaling in Midbrain Dopamine Neurons Increases the Motivation for Food Reward.

    PubMed

    Pandit, Rahul; Omrani, Azar; Luijendijk, Mieneke C M; de Vrind, Véronne A J; Van Rozen, Andrea J; Ophuis, Ralph J A Oude; Garner, Keith; Kallo, Imre; Ghanem, Alexander; Liposits, Zsolt; Conzelmann, Karl-Klaus; Vanderschuren, Louk J M J; la Fleur, Susanne E; Adan, Roger A H

    2016-08-01

    The central melanocortin (MC) system mediates its effects on food intake via MC3 (MC3R) and MC4 receptors (MC4R). Although the role of MC4R in meal size determination, satiation, food preference, and motivation is well established, the involvement of MC3R in the modulation of food intake has been less explored. Here, we investigated the role of MC3R on the incentive motivation for food, which is a crucial component of feeding behavior. Dopaminergic neurons within the ventral tegmental area (VTA) have a crucial role in the motivation for food. We here report that MC3Rs are expressed on VTA dopaminergic neurons and that pro-opiomelanocortinergic (POMC) neurons in the arcuate nucleus of the hypothalamus (Arc) innervate these VTA dopaminergic neurons. Our findings show that intracerebroventricular or intra-VTA infusion of the selective MC3R agonist γMSH increases responding for sucrose under a progressive ratio schedule of reinforcement, but not free sucrose consumption in rats. Furthermore, ex vivo electrophysiological recordings show increased VTA dopaminergic neuronal activity upon γMSH application. Consistent with a dopamine-mediated effect of γMSH, the increased motivation for sucrose after intra-VTA infusion of γMSH was blocked by pretreatment with the dopamine receptor antagonist α-flupenthixol. Taken together, we demonstrate an Arc POMC projection onto VTA dopaminergic neurons that modulates motivation for palatable food via activation of MC3R signaling.

  7. Adipose tissue R2* signal is increased in subjects with obesity: A preliminary MRI study.

    PubMed

    Fernández-Real, José Manuel; Blasco, Gerard; Puig, Josep; Moreno, Maria; Xifra, Gemma; Sánchez-Gonzalez, Javier; Maria Alustiza, Jose; Pedraza, Salvador; Ricart, Wifredo; María Moreno-Navarrete, José

    2016-02-01

    Circulating and adipose tissue markers of iron overload are increased in subjects with obesity. The aim is to study iron signals in adipose tissue. Adipose tissue R2* values and hepatic iron concentration (HIC) were evaluated using magnetic resonance imaging (MRI) in 23 middle-aged subjects with obesity and 20 subjects without obesity. Subcutaneous (SAT) and visceral adipose tissue (VAT) R2* were increased in subjects with obesity (P = 0.004 and P = 0.008) and correlated significantly and positively with HIC in all subjects. Strikingly, most of the associations of liver iron with metabolic parameters were replicated with SAT and VAT R2*. BMI, waist circumference, fat mass, HOMA value, and C-reactive protein positively correlated with HIC and SAT and VAT R2*. BMI or percent fat mass (but not insulin resistance) contributed independently to 26.8-34.8% of the variance in sex- and age-adjusted SAT or VAT R2* (β > 0.40, P < 0.005). Within subjects with obesity, total cholesterol independently contributed to 14.8% of sex- and age-adjusted VAT iron variance (β = 0.50, P = 0.025). Increased R2* in adipose tissue, which might indicate iron content, runs in parallel to liver iron stores of subjects with obesity. VAT iron seems also associated with serum cholesterol within subjects with obesity. © 2015 The Obesity Society.

  8. Aspirin increases metabolism through germline signalling to extend the lifespan of Caenorhabditis elegans

    PubMed Central

    Huang, Xiao-Bing; Mu, Xiao-Hui; Wan, Qin-Li; He, Xiao-Ming; Wu, Gui-Sheng

    2017-01-01

    Aspirin is a prototypic cyclooxygenase inhibitor with a variety of beneficial effects on human health. It prevents age-related diseases and delays the aging process. Previous research has shown that aspirin might act through a dietary restriction-like mechanism to extend lifespan. To explore the mechanism of action of aspirin on aging, we determined the whole-genome expression profile of Caenorhabditis elegans treated with aspirin. Transcriptome analysis revealed the RNA levels of genes involved in metabolism were primarily increased. Reproduction has been reported to be associated with metabolism. We found that aspirin did not extend the lifespan or improve the heat stress resistance of germline mutants of glp-1. Furthermore, Oil Red O staining showed that aspirin treatment decreased lipid deposition and increased expression of lipid hydrolysis and fatty acid β-oxidation-related genes. The effect of germline ablation on lifespan was mainly mediated by DAF-12 and DAF-16. Next, we performed genetic analysis with a series of worm mutants and found that aspirin did not further extend the lifespans of daf-12 and daf-16 single mutants, glp-1;daf-12 and glp-1;daf-16 double mutants, or glp-1;daf-12;daf-16 triple mutants. The results suggest that aspirin increase metabolism and regulate germline signalling to activate downstream DAF-12 and DAF-16 to extend lifespan. PMID:28910305

  9. Aspirin increases metabolism through germline signalling to extend the lifespan of Caenorhabditis elegans.

    PubMed

    Huang, Xiao-Bing; Mu, Xiao-Hui; Wan, Qin-Li; He, Xiao-Ming; Wu, Gui-Sheng; Luo, Huai-Rong

    2017-01-01

    Aspirin is a prototypic cyclooxygenase inhibitor with a variety of beneficial effects on human health. It prevents age-related diseases and delays the aging process. Previous research has shown that aspirin might act through a dietary restriction-like mechanism to extend lifespan. To explore the mechanism of action of aspirin on aging, we determined the whole-genome expression profile of Caenorhabditis elegans treated with aspirin. Transcriptome analysis revealed the RNA levels of genes involved in metabolism were primarily increased. Reproduction has been reported to be associated with metabolism. We found that aspirin did not extend the lifespan or improve the heat stress resistance of germline mutants of glp-1. Furthermore, Oil Red O staining showed that aspirin treatment decreased lipid deposition and increased expression of lipid hydrolysis and fatty acid β-oxidation-related genes. The effect of germline ablation on lifespan was mainly mediated by DAF-12 and DAF-16. Next, we performed genetic analysis with a series of worm mutants and found that aspirin did not further extend the lifespans of daf-12 and daf-16 single mutants, glp-1;daf-12 and glp-1;daf-16 double mutants, or glp-1;daf-12;daf-16 triple mutants. The results suggest that aspirin increase metabolism and regulate germline signalling to activate downstream DAF-12 and DAF-16 to extend lifespan.

  10. Proinflammatory cytokine levels in patients with conversion disorder.

    PubMed

    Tiyekli, Utkan; Calıyurt, Okan; Tiyekli, Nimet Dilek

    2013-06-01

    It was aimed to evaluate the relationship between proinflammatory cytokine levels and conversion disorder both commonly known as stress regulated. Baseline proinflammatory cytokine levels-[Tumour necrosis factor alpha (TNF-α), Interleukin-1 beta (IL-1β), Interleukin-6 (IL-6)]-were evaluated with enzyme-linked immunosorbent assay in 35 conversion disorder patients and 30 healthy controls. Possible changes in proinflammatory cytokine levels were evaluated again, after their acute phase in conversion disorder patients. Statistically significant decreased serum TNF-α levels were obtained in acute phase of conversion disorder. Those levels increased after acute conversion phase. There were no statistically significant difference observed between groups in serum IL-1β and (IL-6) levels. Stress associated with conversion disorder may suppress immune function in acute conversion phase and may have diagnostic and therapeutic value.

  11. Regulation of proinflammatory genes by the circulating microRNA hsa-miR-939.

    PubMed

    McDonald, Marguerite K; Ramanathan, Sujay; Touati, Andrew; Zhou, Yiqian; Thanawala, Rushi U; Alexander, Guillermo M; Sacan, Ahmet; Ajit, Seena K

    2016-08-08

    Circulating microRNAs are beneficial biomarkers because of their stability and dysregulation in diseases. Here we sought to determine the role of miR-939, a miRNA downregulated in patients with complex regional pain syndrome (CRPS). Hsa-miR-939 is predicted to target several proinflammatory genes, including IL-6, VEGFA, TNFα, NFκB2, and nitric oxide synthase 2 (NOS2A). Binding of miR-939 to the 3' untranslated region of these genes was confirmed by reporter assay. Overexpression of miR-939 in vitro resulted in reduction of IL-6, NOS2A and NFκB2 mRNAs, IL-6, VEGFA, and NOS2 proteins and NFκB activation. We observed a significant decrease in the NOS substrate l-arginine in plasma from CRPS patients, suggesting reduced miR-939 levels may contribute to an increase in endogenous NOS2A levels and NO, and thereby to pain and inflammation. Pathway analysis showed that miR-939 represents a critical regulatory node in a network of inflammatory mediators. Collectively, our data suggest that miR-939 may regulate multiple proinflammatory genes and that downregulation of miR-939 in CRPS patients may increase expression of these genes, resulting in amplification of the inflammatory pain signal transduction cascade. Circulating miRNAs may function as crucial signaling nodes, and small changes in miRNA levels may influence target gene expression and thus disease.

  12. The Role of Proinflammatory Cytokine Interleukin-18 in Radiation Injury

    PubMed Central

    Xiao, Mang

    2016-01-01

    Abstract Massive radiation-induced inflammatory factors released from injured cells may cause innate and acquired immune reactions that can further result in stress response signal activity-induced local and systemic damage. IL‐1 family members IL‐1β, IL‐18, and IL‐33 play key roles in inflammatory and immune responses and have been recognized to have significant influences on the pathogenesis of diseases. IL‐1β, IL‐18, and IL‐33 share similarities of cytokine biology, but differences exist in signaling pathways. A key component of the inflammatory reaction is the inflammasome, which is a caspase‐1‐containing multiprotein oligomer. Pathological stimuli such as radiation can induce inflammasome and caspase‐1 activation, and subsequently cause maturation (activation) of pro-forms of IL‐1 and IL‐18 upon caspase‐1 cleavage. This caspase‐1 dependent and IL‐1 and IL‐18 associated cell damage is defined as pyroptosis. Activated IL‐1 and IL‐18 as proinflammatory cytokines drive pathology at different immune and inflammatory disorders through Toll-like receptor (TLR) signaling. While the mechanisms of IL‐1β-induced pathophysiology of diseases have been well studied, IL‐18 has received less attention. The author recently reported that gamma radiation highly increased IL‐1β, IL‐18 and IL‐33 expression in mouse thymus, spleen and/or bone marrow cells; also circulating IL‐18 can be used as a radiation biomarker to track radiation injury in mice, minipigs, and nonhuman primates. This mini-review focuses on the role of IL‐18 in response to gamma radiation-induced injury. PMID:27356067

  13. Pro-Inflammatory and Pro-Oxidant Status of Pancreatic Islet In Vitro Is Controlled by TLR-4 and HO-1 Pathways

    PubMed Central

    Vivot, Kevin; Langlois, Allan; Bietiger, William; Dal, Stéphanie; Seyfritz, Elodie; Pinget, Michel; Jeandidier, Nathalie; Maillard, Elisa; Gies, Jean-Pierre; Sigrist, Séverine

    2014-01-01

    Since their isolation until implantation, pancreatic islets suffer a major stress leading to the activation of inflammatory reactions. The maintenance of controlled inflammation is essential to preserve survival and function of the graft. Identification and targeting of pathway(s) implicated in post-transplant detrimental inflammatory events, is mandatory to improve islet transplantation success. We sought to characterize the expression of the pro-inflammatory and pro-oxidant mediators during islet culture with a focus on Heme oxygenase (HO-1) and Toll-like receptors-4 signaling pathways. Rat pancreatic islets were isolated and pro-inflammatory and pro-oxidant status were evaluated after 0, 12, 24 and 48 hours of culture through TLR-4, HO-1 and cyclooxygenase-2 (COX-2) expression, CCL-2 and IL-6 secretion, ROS (Reactive Oxygen Species) production (Dihydroethidine staining, DHE) and macrophages migration. To identify the therapeutic target, TLR4 inhibition (CLI-095) and HO-1 activation (cobalt protoporphyrin,CoPP) was performed. Activation of NFκB signaling pathway was also investigated. After isolation and during culture, pancreatic islet exhibited a proinflammatory and prooxidant status (increase levels of TLR-4, COX-2, CCL-2, IL-6, and ROS). Activation of HO-1 or inhibition of TLR-4 decreased inflammatory status and oxidative stress of islets. Moreover, the overexpression of HO-1 induced NFκB phosphorylation while the inhibition of TLR-4 had no effect NFκB activation. Finally, inhibition of pro-inflammatory pathway induced a reduction of macrophages migration. These data demonstrated that the TLR-4 signaling pathway is implicated in early inflammatory events leading to a pro-inflammatory and pro-oxidant status of islets in vitro. Moreover, these results provide the mechanism whereby the benefits of HO-1 target in TLR-4 signaling pathway. HO-1 could be then an interesting target to protect islets before transplantation. PMID:25343247

  14. Conditional ablation of myeloid TNF increases lesion volume after experimental stroke in mice, possibly via altered ERK1/2 signaling

    PubMed Central

    Clausen, Bettina Hjelm; Degn, Matilda; Sivasaravanaparan, Mithula; Fogtmann, Torben; Andersen, Maria Gammelstrup; Trojanowsky, Michelle D.; Gao, Han; Hvidsten, Svend; Baun, Christina; Deierborg, Tomas; Finsen, Bente; Kristensen, Bjarne Winther; Bak, Sara Thornby; Meyer, Morten; Lee, Jae; Nedospasov, Sergei A.; Brambilla, Roberta; Lambertsen, Kate Lykke

    2016-01-01

    Microglia are activated following cerebral ischemia and increase their production of the neuro- and immunomodulatory cytokine tumor necrosis factor (TNF). To address the function of TNF from this cellular source in focal cerebral ischemia we used TNF conditional knock out mice (LysMcreTNFfl/fl) in which the TNF gene was deleted in cells of the myeloid lineage, including microglia. The deletion reduced secreted TNF levels in lipopolysaccharide-stimulated cultured primary microglia by ~93%. Furthermore, phosphorylated-ERK/ERK ratios were significantly decreased in naïve LysMcreTNFfl/fl mice demonstrating altered ERK signal transduction. Micro-PET using 18[F]-fluorodeoxyglucose immediately after focal cerebral ischemia showed increased glucose uptake in LysMcreTNFfl/fl mice, representing significant metabolic changes, that translated into increased infarct volumes at 24 hours and 5 days compared to littermates (TNFfl/fl). In naïve LysMcreTNFfl/fl mice cytokine levels were low and comparable to littermates. At 6 hours, TNF producing microglia were reduced by 56% in the ischemic cortex in LysMcreTNFfl/fl mice compared to littermate mice, whereas no TNF+ leukocytes were detected. At 24 hours, pro-inflammatory cytokine (TNF, IL-1β, IL-6, IL-5 and CXCL1) levels were significantly lower in LysMcreTNFfl/fl mice, despite comparable infiltrating leukocyte populations. Our results identify microglial TNF as beneficial and neuroprotective in the acute phase and as a modulator of neuroinflammation at later time points after experimental ischemia, which may contribute to regenerative recovery. PMID:27384243

  15. Conditional ablation of myeloid TNF increases lesion volume after experimental stroke in mice, possibly via altered ERK1/2 signaling.

    PubMed

    Clausen, Bettina Hjelm; Degn, Matilda; Sivasaravanaparan, Mithula; Fogtmann, Torben; Andersen, Maria Gammelstrup; Trojanowsky, Michelle D; Gao, Han; Hvidsten, Svend; Baun, Christina; Deierborg, Tomas; Finsen, Bente; Kristensen, Bjarne Winther; Bak, Sara Thornby; Meyer, Morten; Lee, Jae; Nedospasov, Sergei A; Brambilla, Roberta; Lambertsen, Kate Lykke

    2016-07-07

    Microglia are activated following cerebral ischemia and increase their production of the neuro- and immunomodulatory cytokine tumor necrosis factor (TNF). To address the function of TNF from this cellular source in focal cerebral ischemia we used TNF conditional knock out mice (LysMcreTNF(fl/fl)) in which the TNF gene was deleted in cells of the myeloid lineage, including microglia. The deletion reduced secreted TNF levels in lipopolysaccharide-stimulated cultured primary microglia by ~93%. Furthermore, phosphorylated-ERK/ERK ratios were significantly decreased in naïve LysMcreTNF(fl/fl) mice demonstrating altered ERK signal transduction. Micro-PET using (18)[F]-fluorodeoxyglucose immediately after focal cerebral ischemia showed increased glucose uptake in LysMcreTNF(fl/fl) mice, representing significant metabolic changes, that translated into increased infarct volumes at 24 hours and 5 days compared to littermates (TNFfl/fl). In naïve LysMcreTNF(fl/fl) mice cytokine levels were low and comparable to littermates. At 6 hours, TNF producing microglia were reduced by 56% in the ischemic cortex in LysMcreTNF(fl/fl) mice compared to littermate mice, whereas no TNF(+) leukocytes were detected. At 24 hours, pro-inflammatory cytokine (TNF, IL-1β, IL-6, IL-5 and CXCL1) levels were significantly lower in LysMcreTNF(fl/fl) mice, despite comparable infiltrating leukocyte populations. Our results identify microglial TNF as beneficial and neuroprotective in the acute phase and as a modulator of neuroinflammation at later time points after experimental ischemia, which may contribute to regenerative recovery.

  16. Protective effect of ixerisoside A against UVB-induced pro-inflammatory cytokine production in human keratinocytes.

    PubMed

    Kim, Sung-Bae; Kim, Ji-Eun; Kang, Ok-Hwa; Mun, Su-Hyun; Seo, Yun-Soo; Kang, Da-Hye; Yang, Da-Wun; Ryu, Shi-Yong; Lee, Young-Mi; Kwon, Dong-Yeul

    2015-05-01

    Human skin is the first line of defense for the protection of the internal organs of the body from different stimuli. Ultraviolet B (UVB), one of the harmful radiations for skin, is widely known to induce abnormally increased cytokine release from keratinocytes leading to inflammatory skin disorders. IL-6 and IL-8 induce an acute-phase response and stimulate leukocyte infiltration in the skin. Previous studies have shown that chronic exposure to UVB radiation increases cyclooxygenase-2 (COX‑2) expression through various cell signaling pathways, resulting in skin cancer. Recent studies have shown that the activation of extracellular signal-regulated kinase (ERK), c-Jun NH2-terminal kinase (JNK), and p38 MAPK is strongly correlated with acute inflammation and development of skin cancer caused by an increased expression of COX-2. Ixerisoside A (IXA) is an active constituent of Ixeris dentata of the Compositae (Asteraceae) family. The effect of IXA on skin inflammation has yet to be elucidated. To determine the anti-inflammatory effects of IXA, we examined its effect on UVB-induced pro-inflammatory cytokine production in human keratinocytes (HaCaT cells) by observing these cells in the presence or absence of IXA. In this study, pro-inflammatory cytokine production was determined by enzyme-linked immunosorbent assay (ELISA), reverse transcription-polymerase chain reaction (rt-pcr), and western blot analysis to evaluate the activation of mitogen-activated protein kinases (MAPKs). IXA inhibited UVB-induced production of the pro-inflammatory cytokines IL-6 and IL-8 in a dose-dependent manner. Moreover, IXA inhibited the expression of COX-2, ERK, JNK, and p38 MAPKs, indicating that the secretion of the pro-inflammatory cytokines IL-6 and IL-8, and COX-2 expression was inhibited by blocking MAPK phosphorylation. These results indicated that IXA potentially protects against UVB-induced skin inflammation.

  17. Increased expression of epidermal growth factor receptor induces sequestration of extracellular signal-related kinases and selective attenuation of specific epidermal growth factor-mediated signal transduction pathways.

    PubMed

    Habib, Amyn A; Chun, Soo Jin; Neel, Benjamin G; Vartanian, Timothy

    2003-01-01

    Increased expression of the epidermal growth factor receptor (EGFR) is common in cancer and correlates with neoplastic progression. Although the biology of this receptor has been the subject of intense investigation, surprisingly little is known about how increased expression of the wild-type EGFR affects downstream signal transduction in cells. We show that increasing the expression of the receptor results in dramatic shifts in signaling with attenuation of EGF-induced Ras, extracellular signal-related kinases (ERKs), and Akt activation, as well as amplification of STAT1 and STAT3 signaling. In this study, we focus on the mechanism of attenuated ERK signaling and present evidence suggesting that the mechanism of attenuated ERK signaling in EGFR-overexpressing cells is a sequestration of ERKs at the cell membrane in EGFR-containing complexes. Increased expression of the EGFR results in an aberrant localization of ERKs to the cell membrane. Furthermore, ERKs become associated with the EGFR in a physical complex in EGFR-overexpressing cells but not in control cells. The EGFR-ERK association is detected in unstimulated cells or on exposure to a low concentration of EGF; under these conditions, ERK activation is minimal. Exposure of these cells to saturating concentrations of EGF results in a decreased membrane localization of ERKs, a concomitant dissociation of ERKs from the EGFR, and restores ERK activation. A similar association can be detected between the EGFR and MEK1 in receptor-overexpressing cells, suggesting that multiple components of the ERK signaling pathway may become trapped in complexes with the EGFR. These findings can be demonstrated in cells transfected to express high levels of the EGFR as well as in cancer cells which naturally overexpress the EGFR and, thus, may be representative of altered EGFR signaling in human cancer.

  18. 1'-Acetoxychavicol Acetate Increases Proteasome Activity by Activating cAMP-PKA Signaling.

    PubMed

    Yaku, Keisuke; Matsui-Yuasa, Isao; Kojima-Yuasa, Akiko

    2017-08-31

    Protein degradation systems are critical pathways for the maintenance of protein homeostasis. The age-dependent attenuation of the proteasome activity contributes to age-related neurodegenerative processes. The molecule 1'-acetoxychavicol acetate (ACA) is naturally obtained from the rhizomes and seeds of Zingiberaceae plants, such as Languas galangal and Alpinia galangal, and exhibits anti-carcinogenic effects. Recently, we have shown that ACA protected the age-related learning and memory impairments in senescence-accelerated mice and maintained cognitive performance. Therefore, we here examined the effects of ACA on the protein degradation systems and cell protection against neurotoxicity in differentiated PC12 cells. ACA increased proteasome activity in PC12 cells. Increased proteasome activity occurred during the initial stages of ACA treatment and lasted at least 9 h. The activity returned to control levels within 24 h. The increase in proteasome activity by ACA was suppressed by H-89, which is a cAMP-dependent protein kinase A inhibitor. ACA increased the adenylate cyclase activity and therefore the intracellular cAMP levels. Furthermore, ACA recovered the initial cell viability, which was reduced after the addition of the amyloid β-protein fragment to neuronally differentiated PC12 cells. The effects of ACA on amyloid toxicity were reduced after treatment with MG132, a proteasome inhibitor. These results demonstrated a neuroprotective effect of ACA via activation of cAMP/cAMP-dependent protein kinase A signaling in neuronally differentiated PC12 cells. Georg Thieme Verlag KG Stuttgart · New York.

  19. Inhibition of a novel specific neuroglial integrin signaling pathway increases STAT3-mediated CNTF expression

    PubMed Central

    2013-01-01

    Background Ciliary neurotrophic factor (CNTF) expression is repressed in astrocytes by neuronal contact in the CNS and is rapidly induced by injury. Here, we defined an inhibitory integrin signaling pathway. Results The integrin substrates laminin, fibronectin and vitronectin, but not collagen, thrombospondin or fibrinogen, reduced CNTF expression in C6 astroglioma cells. Antibodies against αv and β5, but not α6 or β1, integrin induced CNTF. Together, the ligand and antibody specificity suggests that CNTF is repressed by αvβ5 integrin. Antibodies against Thy1, an abundant neuronal surface protein whose function is unclear, induced CNTF in neuron-astrocyte co-cultures indicating that it is a neuroglial CNTF repressor. Inhibition of the integrin signaling molecule Focal Adhesion Kinase (FAK) or the downstream c-Jun N-terminal kinase (JNK), but not extracellular regulated kinase (ERK) or p38 MAPK, greatly induced CNTF mRNA and protein expression within 4 hours. This selective inhibitory pathway phosphorylated STAT3 on its inhibitory ser-727 residue interfering with activity of the pro-transcription Tyr-705 residue. STAT3 can activate CNTF transcription because it bound to its promoter and FAK antagonist-induced CNTF was reduced by blocking STAT3. Microinjection of FAK inhibitor directly into the brain or spinal cord in adult mice rapidly induced CNTF mRNA and protein expression. Importantly, systemic treatment with FAK inhibitors over 3 days induced CNTF in the subventricular zone and increased neurogenesis. Conclusions Neuron-astroglia contact mediated by integrins serves as a sensor to enable rapid neurotrophic responses and provides a new pharmacological avenue to exploit the neuroprotective properties of endogenous CNTF. PMID:23693126

  20. Increased interoceptive awareness in fear of flying: sensitivity to suffocation signals.

    PubMed

    Vanden Bogaerde, Anouk; Derom, Eric; De Raedt, Rudi

    2011-06-01

    In flight phobia, particular environmental factors can facilitate a fear response. The current study aimed to explore the relationship between respiratory sensations and fear of flying: individuals with fear of flying may be more sensitive to suffocation signals and could experience more bodily sensations as a consequence of an added resistive respiratory load. The sample included 19 subjects with fear of flying and 19 controls. Each subject wore a mask to which a respiratory load could be added. First, an interference paradigm was used: respiratory loads were presented during a tone detection task. Next, subjects were asked to detect the loads. After each task, subjects reported their somatic sensations. All subjects showed interference of the respiratory loads. However, subjects with fear of flying were more accurate in detecting the loads, thereby indicating higher interoceptive awareness. Moreover, their superior accuracy was related to increased bodily sensations: a higher interoceptive awareness resulted in increased symptom reporting. It follows that treatment interventions for fear of flying should be supplemented with interventions that target internal stimuli. Copyright © 2011 Elsevier Ltd. All rights reserved.

  1. Cue-induced craving increases impulsivity via changes in striatal value signals in problem gamblers.

    PubMed

    Miedl, Stephan F; Büchel, Christian; Peters, Jan

    2014-03-26

    Impulsive behavior such as steep temporal discounting is a hallmark of addiction and is associated with relapse. In pathological gamblers, discounting may be further increased by the presence of gambling-related cues in the environment, but the extent to which the gambling relatedness of task settings affects reward responses in gambling addiction is debated. In the present study, human problem gamblers made choices between immediate rewards and individually tailored larger-but-later rewards while visual gambling-related scenes were presented in the background. N = 17 participants were scanned using fMRI, whereas N = 5 additional participants completed a behavioral version of the task. Postscan craving ratings were acquired for each image, and behavioral and neuroimaging data were analyzed separately for high- and low-craving trials (median split analysis). Discounting was steeper for high versus low craving trials. Neuroimaging revealed a positive correlation with model-based subjective value in midbrain and striatum in low-craving trials that was reversed in high-craving trials. These findings reveal a modulation of striatal reward responses in gamblers by addiction-related cues, and highlight a potentially important mechanism that may contribute to relapse. Cue-induced changes in striatal delayed reward signals may lead to increased discounting of future rewards, which might in turn affect the likelihood of relapse.

  2. Increases in Retrograde Injury Signaling Complex-Related Transcripts in Central Axons following Injury

    PubMed Central

    Pathak, Gunja K.; Ornstein, Hannah; Aranda-Espinoza, Helim; Karlsson, Amy J.

    2016-01-01

    Axons in the peripheral nervous system respond to injury by activating retrograde injury signaling (RIS) pathways, which promote local axonal protein synthesis (LPS) and neuronal regeneration. RIS is also initiated following injury of neurons in the central nervous system (CNS). However, regulation of the localization of axonal mRNA required for LPS is not well understood. We used a hippocampal explant system to probe the regulation of axonal levels of RIS-associated transcripts following axonal injury. Axonal levels of importin β1 and RanBP1 were elevated biphasically at 1 and 24 hrs after axotomy. Transcript levels for β-actin, a prototypic axonally synthesized protein, were similarly elevated. Our data suggest differential regulation of axonal transcripts. At 1 hr after injury, deployment of actinomycin revealed that RanBP1, but not importin β1, requires de novo mRNA synthesis. At 24 hrs after injury, use of importazole revealed that the second wave of increased axonal mRNA levels required importin β-mediated nuclear import. We also observed increased importin β1 axonal protein levels at 1 and 6 hrs after injury. RanBP1 levels and vimentin levels fluctuated but were unchanged at 3 and 6 hrs after injury. This study revealed temporally complex regulation of axonal transcript levels, and it has implications for understanding neuronal response to injury in the CNS. PMID:27847648

  3. Perceptual learning increases the strength of the earliest signals in visual cortex.

    PubMed

    Bao, Min; Yang, Lin; Rios, Cristina; He, Bin; Engel, Stephen A

    2010-11-10

    Training improves performance on most visual tasks. Such perceptual learning can modify how information is read out from, and represented in, later visual areas, but effects on early visual cortex are controversial. In particular, it remains unknown whether learning can reshape neural response properties in early visual areas independent from feedback arising in later cortical areas. Here, we tested whether learning can modify feedforward signals in early visual cortex as measured by the human electroencephalogram. Fourteen subjects were trained for >24 d to detect a diagonal grating pattern in one quadrant of the visual field. Training improved performance, reducing the contrast needed for reliable detection, and also reliably increased the amplitude of the earliest component of the visual evoked potential, the C1. Control orientations and locations showed smaller effects of training. Because the C1 arises rapidly and has a source in early visual cortex, our results suggest that learning can increase early visual area response through local receptive field changes without feedback from later areas.

  4. Vision of the body increases interference on the somatic signal detection task.

    PubMed

    Mirams, Laura; Poliakoff, Ellen; Brown, Richard J; Lloyd, Donna M

    2010-05-01

    Research suggests that attention has a significant effect on somatic perception in both healthy people and those who suffer from somatic disturbance. The current study investigates the effects of attending to the body on somatic awareness and a particular type of somatic disturbance: erroneous reports of touch sensation, as measured by the Somatic Signal Detection Task (SSDT). During the SSDT, participants are required to detect near-threshold tactile stimulation at their fingertip. Previous research has found that healthy participants erroneously report touch sensations in the absence of a stimulus on this task and that such false alarms are increased when a simultaneous light flash is presented next to their fingertip. Thirty-seven participants completed the SSDT under two conditions: non-informative vision of the hand and no vision of the hand. False alarms were significantly higher in light trials in the non-informative vision condition compared to light trials in the no-vision condition. However, hit rates, sensitivity (d') and response criterion (c) were not affected by non-informative vision of the hand. Using the SSDT, we found that viewing the body increased somatic interference, possibly due to raised awareness of internal bodily sensations. This work provides evidence that viewing the body can have a detrimental effect on simple detection of near-threshold tactile stimulation.

  5. Proinflammatory cytokines decrease the expression of genes critical for RPE function

    PubMed Central

    Samuel, William; Boyce, Kaifa; Cherukuri, Aswini; Duncan, Todd; Jaworski, Cynthia; Nagineni, Chandrasekharam N.; Redmond, T. Michael

    2016-01-01

    Purpose Proinflammatory cytokines interferon gamma (IFN-γ), tumor necrosis factor alpha (TNF-α), and interleukin-1 beta (IL-1β) secreted by infiltrating lymphocytes or macrophages may play a role in triggering RPE dysfunction associated with age-related macular degeneration (AMD). Binding of these proinflammatory cytokines to their specific receptors residing on the RPE cell surface can activate signaling pathways that, in turn, may dysregulate cellular gene expression. The purpose of the present study was to investigate whether IFN-γ, TNF-α, and IL-1β have an adverse effect on the expression of genes essential for RPE function, employing the RPE cell line ARPE-19 as a model system. Methods ARPE-19 cells were cultured for 3–4 months until they exhibited epithelial morphology and expressed mRNAs for visual cycle genes. The differentiated cells were treated with IFN-γ, TNF-α, and/or IL-1β, and gene expression was analyzed with real-time PCR analysis. Western immunoblotting was employed for the detection of proteins. Results Proinflammatory cytokines (IFN-γ + TNF-α + IL-1β) greatly increased the expression of chemokines and cytokines in cultured ARPE-19 cells that exhibited RPE characteristics. However, this response was accompanied by markedly decreased expression of genes important for RPE function, such as CDH1, RPE65, RDH5, RDH10, TYR, and MERTK. This was associated with decreased expression of the genes MITF, TRPM1, and TRPM3, as well as microRNAs miR-204 and miR-211, which are known to regulate RPE-specific gene expression. The decreased expression of the epithelial marker gene CDH1 was associated with increased expression of mesenchymal marker genes (CDH2, VIM, and CCND1) and epithelial–mesenchymal transition (EMT) promoting transcription factor genes (ZEB1 and SNAI1). Conclusions RPE cells exposed to proinflammatory cytokines IFN-γ, TNF-α, and IL-1β showed decreased expression of key genes involved in the visual cycle, epithelial morphology

  6. Bile acids promote diethylnitrosamine-induced hepatocellular carcinoma via increased inflammatory signaling.

    PubMed

    Sun, Lina; Beggs, Kevin; Borude, Prachi; Edwards, Genea; Bhushan, Bharat; Walesky, Chad; Roy, Nairita; Manley, Michael W; Gunewardena, Sumedha; O'Neil, Maura; Li, Hua; Apte, Udayan

    2016-07-01

    Hepatocellular carcinoma (HCC) is the most common hepatic malignancy and the third leading cause of cancer related deaths. Previous studies have implicated bile acids in pathogenesis of HCC, but the mechanisms are not known. We investigated the mechanisms of HCC tumor promotion by bile acids the diethylnitrosamine (DEN)-initiation-cholic acid (CA)-induced tumor promotion protocol in mice. The data show that 0.2% CA treatment resulted in threefold increase in number and size of DEN-induced liver tumors. All tumors observed in DEN-treated mice were well-differentiated HCCs. The HCCs observed in DEN-treated CA-fed mice exhibited extensive CD3-, CD20-, and CD45-positive inflammatory cell aggregates. Microarray-based global gene expression studies combined with Ingenuity Pathway Analysis revealed significant activation of NF-κB and Nanog in the DEN-treated 0.2% CA-fed livers. Further studies showed significantly higher TNF-α and IL-1β mRNA, a marked increase in total and phosphorylated-p65 and phosphorylated IκBα (degradation form) in livers of DEN-treated 0.2% CA-fed mice. Treatment of primary mouse hepatocytes with various bile acids showed significant induction of stemness genes including Nanog, KLF4, Sox2, and Oct4. Quantification of total and 20 specific bile acids in liver, and serum revealed a tumor-associated bile acid signature. Finally, quantification of total serum bile acids in normal, cirrhotic, and HCC human samples revealed increased bile acids in serum of cirrhotic and HCC patients. Taken together, these data indicate that bile acids are mechanistically involved pathogenesis of HCC and may promote HCC formation via activation of inflammatory signaling. Copyright © 2016 the American Physiological Society.

  7. Early Retinal Neuronal Dysfunction in Diabetic Mice: Reduced Light-Evoked Inhibition Increases Rod Pathway Signaling

    PubMed Central

    Moore-Dotson, Johnnie M.; Beckman, Jamie J.; Mazade, Reece E.; Hoon, Mrinalini; Bernstein, Adam S.; Romero-Aleshire, Melissa J.; Brooks, Heddwen L.; Eggers, Erika D.

    2016-01-01

    Purpose Recent studies suggest that the neural retinal response to light is compromised in diabetes. Electroretinogram studies suggest that the dim light retinal rod pathway is especially susceptible to diabetic damage. The purpose of this study was to determine whether diabetes alters rod pathway signaling. Methods Diabetes was induced in C57BL/6J mice by three intraperitoneal injections of streptozotocin (STZ; 75 mg/kg), and confirmed by blood glucose levels > 200 mg/dL. Six weeks after the first injection, whole-cell voltage clamp recordings of spontaneous and light-evoked inhibitory postsynaptic currents from rod bipolar cells were made in dark-adapted retinal slices. Light-evoked excitatory currents from rod bipolar and AII amacrine cells, and spontaneous excitatory currents from AII amacrine cells were also measured. Receptor inputs were pharmacologically isolated. Immunohistochemistry was performed on whole mounted retinas. Results Rod bipolar cells had reduced light-evoked inhibitory input from amacrine cells but no change in excitatory input from rod photoreceptors. Reduced light-evoked inhibition, mediated by both GABAA and GABAC receptors, increased rod bipolar cell output onto AII amacrine cells. Spontaneous release of GABA onto rod bipolar cells was increased, which may limit GABA availability for light-evoked release. These physiological changes occurred in the absence of retinal cell loss or changes in GABAA receptor expression levels. Conclusions Our results indicate that early diabetes causes deficits in the rod pathway leading to decreased light-evoked rod bipolar cell inhibition and increased rod pathway output that provide a basis for the development of early diabetic visual deficits. PMID:27028063

  8. Globular adiponectin induces a pro-inflammatory response in human astrocytic cells.

    PubMed

    Wan, Zhongxiao; Mah, Dorrian; Simtchouk, Svetlana; Klegeris, Andis; Little, Jonathan P

    2014-03-28

    Neuroinflammation, mediated in part by activated brain astrocytes, plays a critical role in the development of neurodegenerative disorders, including Alzheimer's disease (AD). Adiponectin is the most abundant adipokine secreted from adipose tissue and has been reported to exert both anti- and pro-inflammatory effects in peripheral tissues; however, the effects of adiponectin on astrocytes remain unknown. Shifts in peripheral concentrations of adipokines, including adiponectin, could contribute to the observed link between midlife adiposity and increased AD risk. The aim of the present study was to characterize the effects of globular adiponectin (gAd) on pro-inflammatory cytokine mRNA expression and secretion in human U373 MG astrocytic cells and to explore the potential involvement of nuclear factor (NF)-κB, p38 mitogen-activated protein kinase (MAPK), extracellular signal-regulated kinase (ERK)1/2, c-Jun N-terminal kinase (JNK) and phosphatidylinositide 3-kinases (PI3K) signaling pathways in these processes. We demonstrated expression of adiponectin receptor 1 (adipoR1) and adipoR2 in U373 MG cells and primary human astrocytes. gAd induced secretion of interleukin (IL)-6 and monocyte chemoattractant protein (MCP)-1, and gene expression of IL-6, MCP-1, IL-1β and IL-8 in U373 MG cells. Using specific inhibitors, we found that NF-κB, p38MAPK and ERK1/2 pathways are involved in gAd-induced induction of cytokines with ERK1/2 contributing the most. These findings provide evidence that gAd may induce a pro-inflammatory phenotype in human astrocytes.

  9. Alarmin S100A9 Induces Proinflammatory and Catabolic Effects Predominantly in the M1 Macrophages of Human Osteoarthritic Synovium.

    PubMed

    van den Bosch, Martijn H; Blom, Arjen B; Schelbergen, Rik F; Koenders, Marije I; van de Loo, Fons A; van den Berg, Wim B; Vogl, Thomas; Roth, Johannes; van der Kraan, Peter M; van Lent, Peter L

    2016-10-01

    The alarmins S100A8 and S100A9 have been shown to regulate synovial activation, cartilage damage, and osteophyte formation in osteoarthritis (OA). Here we investigated the effect of S100A9 on the production of proinflammatory cytokines and matrix metalloprotease (MMP) in OA synovium, granulocyte macrophage colony-stimulating factor (GM-CSF)-differentiated/macrophage colony-stimulating factor (M-CSF)-differentiated macrophages, and OA fibroblasts. We determined which cell types in the synovium produced S100A8 and S100A9. Further, the production of proinflammatory cytokines and MMP, and the activation of canonical Wnt signaling, was determined in human OA synovium, OA fibroblasts, and monocyte-derived macrophages following stimulation with S100A9. We observed that S100A8 and S100A9 were mainly produced by GM-CSF-differentiated macrophages present in the synovium, and to a lesser extent by M-CSF-differentiated macrophages, but not by fibroblasts. S100A9 stimulation of OA synovial tissue increased the production of the proinflammatory cytokines interleukin (IL) 1β, IL-6, IL-8, and tumor necrosis factor-α. Additionally, various MMP were upregulated after S100A9 stimulation. Experiments to determine which cell type was responsible for these effects revealed that mainly stimulation of GM-CSF-differentiated macrophages and to a lesser extent M-CSF-differentiated macrophages with S100A9 increased the expression of these proinflammatory cytokines and MMP. In contrast, stimulation of fibroblasts with S100A9 did not affect their expression. Finally, stimulation of GM-CSF-differentiated, but not M-CSF-differentiated macrophages with S100A9 activated canonical Wnt signaling, whereas incubation of OA synovium with the S100A9 inhibitor paquinimod reduced the activation of canonical Wnt signaling. Predominantly mediated by M1-like macrophages, the alarmin S100A9 stimulates the production of proinflammatory and catabolic mediators and activates canonical Wnt signaling in OA

  10. ALPK1 affects testosterone mediated regulation of proinflammatory cytokines production.

    PubMed

    Kuo, Tzer-Min; Yeh, Kun-Tu; Hsu, Hui-Ting; Chiang, Shang-Lun; Chang, Jan-Gowth; Huang, Chung-Ming; Tu, Hung-Pin; Liu, Chiu-Shong; Ko, Ying-Chin

    2015-11-01

    Alpha-protein kinase 1, also known as alpha-kinase 1 (ALPK1), is associated with chronic kidney disease (CKD), myocardial infarction, gout and type 2 diabetes mellitus (DM). In addition to having an inductive effect on the proinflammatory cytokines in monocytic THP1 cells, ALPK1 is expressed abundantly in the mouse testes. Low testosterone levels are commonly associated with arthritis, CKD, type 2 DM, cardiovascular disease and inflammation. The testosterone's anti-inflammatory effect has been demonstrated to reduce proinflammatory cytokines and adhesion molecules. In this study, we found that ALPK1 transgenic mice showed lower levels of testosterone in both the testes and the serum. Decreasing endogenous ALPK1 enhanced testosterone levels and transcripts of testosterone-regulated genes (P450scc, 3beta-HSD, P450C17, 17beta-HSD, StAR, and INSL3) in TM3 Leydig cells. In contrast, increasing testosterone decreased ALPK1 in both TM3 and monocytic THP1 cells. This decrease was accompanied by a reduction of the proinflammatory cytokines. Increased ALPK1 levels attenuated the testosterone effects in THP1 cells. Finally, we also found that ALPK1 increased the release of TNF-alpha and TGF-beta1 in the human embryonic kidney 293 cells, while testosterone inhibited ALPK1 in the primary kidney cells. Taken together, this data suggests that the balance between ALPK1 and testosterone plays a critical role in the testosterone-mediated inhibition of proinflammatory cytokines.

  11. Mitogen-activated protein kinases and phosphatidylinositol 3-kinase are involved in Prevotella intermedia-induced proinflammatory cytokines expression in human periodontal ligament cells.

    PubMed

    Guan, Su-Min; Zhang, Ming; He, Jian-Jun; Wu, Jun-Zheng

    2009-08-28

    Chronic periodontitis is an inflammatory disease affecting periodontal connective tissues and alveolar bone. Proinflammatory mediators induced by periodontal pathogens play vital roles in the initiation and progression of the disease. In this study, we examined whether Prevotella intermedia induces proinflammatory cytokines expression in human periodontal ligament cells (hPDLs). The mRNA expression and protein production were determined by reverse transcription-polymerase chain reaction (RT-PCR) and enzyme-linked immunosorbant assay (ELISA) respectively. P. intermedia treatment dose- and time-dependently increased IL-6, IL-8 and M-CSF, but not IL-1beta and TNF-alpha mRNA expression and protein secretion. Preincubation of hPDLs with extracellular signal-regulated kinase (ERK), c-Jun N-terminal kinase (JNK), p38 kinase and phosphatidylinositol 3-kinase (PI3K) inhibitors PD98059, SP600125, SB203580 and LY294002 resulted in significant reduction in P. intermedia-induced IL-6, IL-8 and M-CSF expression. Blocking the synthesis of prostaglandin E(2) (PGE(2)) by indomethacin also abolished the stimulatory effects of P. intermedia on cytokines expression. Our results indicate that P. intermedia induces proinflammatory cytokines through MAPKs and PI3K signaling pathways, and PGE(2) is involved in the P. intermedia-induced proinflammatory cytokines upregulation.

  12. Cortisol-treated zebrafish embryos develop into pro-inflammatory adults with aberrant immune gene regulation

    PubMed Central

    Hartig, Ellen I.; Zhu, Shusen; King, Benjamin L.

    2016-01-01

    ABSTRACT Chronic early-life stress increases adult susceptibility to numerous health problems linked to chronic inflammation. One way that this may occur is via glucocorticoid-induced developmental programming. To gain insight into such programming we treated zebrafish embryos with cortisol and examined the effects on both larvae and adults. Treated larvae had elevated whole-body cortisol and glucocorticoid signaling, and upregulated genes associated with defense response and immune system processes. In adulthood the treated fish maintained elevated basal cortisol levels in the absence of exogenous cortisol, and constitutively mis-expressed genes involved in defense response and its regulation. Adults derived from cortisol-treated embryos displayed defective tailfin regeneration, heightened basal expression of pro-inflammatory genes, and failure to appropriately regulate those genes following injury or immunological challenge. These results support the hypothesis that chronically elevated glucocorticoid signaling early in life directs development of a pro-inflammatory adult phenotype, at the expense of immunoregulation and somatic regenerative capacity. PMID:27444789

  13. Putrescine as a signal to modulate the indispensable ABA increase under cold stress

    PubMed Central

    Cuevas, Juan C; López-Cobollo, Rosa; Alcázar, Rubén; Zarza, Xavier; Koncz, Csaba; Altabella, Teresa; Salinas, Julio; Tiburcio, Antonio F

    2009-01-01

    Polyamines have been found to correlate frequently with biotic and abiotic insults, and their functional involvement in the plant responses to several stresses has been shown genetically with both gain and loss of function mutations. In spite of a large body of physiological and genetic data, the mode of action for polyamines at the molecular level still remains elusive. We have recently performed a detailed integrated analysis of polyamine metabolism under cold stress by means of metabolic studies, quantitative gene expression analyses, and gene inactivations, to characterize in more detail the role of polyamines in response to low temperature. Our data show a unique accumulation profile for putrescine compared to other polyamines, with a progressive increase upon cold stress treatment coincident with a similar transcriptional upregulation for the two arginine decarboxylase genes ADC1 and ADC2. Loss of function mutants adc1 and adc2 display reduced freezing tolerance and alterations in ABA content and ABA-dependent signalling pathways under low temperature, compared to wild type plants. Phenotypical reverse complementation tests for both adc and ABA-defective mutants support our conclusion that putrescine modulates ABA biosynthesis at the transcriptional level in response to low temperature thus uncovering a novel mode of action for polyamines as regulators of hormone biosynthesis. PMID:19721755

  14. Increased signals from short-wavelength-excited fluorescent molecules using sub-Ti:Sapphire wavelengths.

    PubMed

    Norris, G; Amor, R; Dempster, J; Amos, W B; McConnell, G

    2012-11-01

    We report the use of an all-solid-state ultrashort pulsed source specifically for two-photon microscopy at wavelengths shorter than those of the conventional Ti:Sapphire laser. Our approach involves sum-frequency mixing of the output from an optical parametric oscillator (λ= 1400-1640 nm) synchronously pumped by a Yb-doped fibre laser (λ= 1064 nm), with the residual pump radiation. This generated an fs-pulsed output tunable in the red spectral region (λ= 620-636 nm, ~150 mW, 405 fs, 80 MHz, M(2) ~ 1.3). We demonstrate the performance of our ultrashort pulsed system using fluorescently labelled and autofluorescent tissue, and compare with conventional Ti:Sapphire excitation. We observe a more than 3-fold increase in fluorescence signal intensity using our visible laser source in comparison with the Ti:Sapphire laser for two-photon excitation at equal illumination peak powers of 1.16 kW or less.

  15. Beta cell compensation for insulin resistance in Zucker fatty rats: increased lipolysis and fatty acid signalling.

    PubMed

    Nolan, C J; Leahy, J L; Delghingaro-Augusto, V; Moibi, J; Soni, K; Peyot, M-L; Fortier, M; Guay, C; Lamontagne, J; Barbeau, A; Przybytkowski, E; Joly, E; Masiello, P; Wang, S; Mitchell, G A; Prentki, M

    2006-09-01

    The aim of this study was to determine the role of fatty acid signalling in islet beta cell compensation for insulin resistance in the Zucker fatty fa/fa (ZF) rat, a genetic model of severe obesity, hyperlipidaemia and insulin resistance that does not develop diabetes. NEFA augmentation of insulin secretion and fatty acid metabolism were studied in isolated islets from ZF and Zucker lean (ZL) control rats. Exogenous palmitate markedly potentiated glucose-stimulated insulin secretion (GSIS) in ZF islets, allowing robust secretion at physiological glucose levels (5-8 mmol/l). Exogenous palmitate also synergised with glucagon-like peptide-1 and the cyclic AMP-raising agent forskolin to enhance GSIS in ZF islets only. In assessing islet fatty acid metabolism, we found increased glucose-responsive palmitate esterification and lipolysis processes in ZF islets, suggestive of enhanced triglyceride-fatty acid cycling. Interruption of glucose-stimulated lipolysis by the lipase inhibitor Orlistat (tetrahydrolipstatin) blunted palmitate-augmented GSIS in ZF islets. Fatty acid oxidation was also higher at intermediate glucose levels in ZF islets and steatotic triglyceride accumulation was absent. The results highlight the potential importance of NEFA and glucoincretin enhancement of insulin secretion in beta cell compensation for insulin resistance. We propose that coordinated glucose-responsive fatty acid esterification and lipolysis processes, suggestive of triglyceride-fatty acid cycling, play a role in the coupling mechanisms of glucose-induced insulin secretion as well as in beta cell compensation and the hypersecretion of insulin in obesity.

  16. Enhanced astroglial Ca2+ signaling increases excitatory synaptic strength in the epileptic brain.

    PubMed

    Álvarez-Ferradas, Carla; Morales, Juan Carlos; Wellmann, Mario; Nualart, Francisco; Roncagliolo, Manuel; Fuenzalida, Marco; Bonansco, Christian

    2015-09-01

    The fine-tuning of synaptic transmission by astrocyte signaling is crucial to CNS physiology. However, how exactly astroglial excitability and gliotransmission are affected in several neuropathologies, including epilepsy, remains unclear. Here, using a chronic model of temporal lobe epilepsy (TLE) in rats, we found that astrocytes from astrogliotic hippocampal slices displayed an augmented incidence of TTX-insensitive spontaneous slow Ca(2+) transients (STs), suggesting a hyperexcitable pattern of astroglial activity. As a consequence, elevated glutamate-mediated gliotransmission, observed as increased slow inward current (SICs) frequency, up-regulates the probability of neurotransmitter release in CA3-CA1 synapses. Selective blockade of spontaneous astroglial Ca(2+) elevations as well as the inhibition of purinergic P2Y1 or mGluR5 receptors relieves the abnormal enhancement of synaptic strength. Moreover, mGluR5 blockade eliminates any synaptic effects induced by P2Y1R inhibition alone, suggesting that the Pr modulation via mGluR occurs downstream of P2Y1R-mediated Ca(2+)-dependent glutamate release from astrocyte. Our findings show that elevated Ca(2+)-dependent glutamate gliotransmission from hyperexcitable astrocytes up-regulates excitatory neurotransmission in epileptic hippocampus, suggesting that gliotransmission should be considered as a novel functional key in a broad spectrum of neuropathological conditions. © 2015 Wiley Periodicals, Inc.

  17. Increased BOLD signal in the fusiform gyrus during implicit emotion processing in anorexia nervosa.

    PubMed

    Fonville, Leon; Giampietro, Vincent; Surguladze, Simon; Williams, Steven; Tchanturia, Kate

    2014-01-01

    The behavioural literature in anorexia nervosa (AN) has suggested impairments in psychosocial functioning and studies using facial expression processing tasks (FEPT) have reported poorer recognition and slower identification of emotions. Functional magnetic resonance imaging (fMRI) was used alongside a FEPT, depicting neutral, mildly happy and happy faces, to examine the neural correlates of implicit emotion processing in AN. Participants were instructed to specify the gender of the faces. Levels of depression, anxiety, obsessive-compulsive symptoms and eating disorder behaviour were obtained and principal component analysis (PCA) was performed to acquire uncorrelated variables. fMRI analysis revealed a greater blood-oxygenation level dependent (BOLD) response in AN in the right fusiform gyrus to all facial expressions. This response showed a linear increase with the happiness of the facial expression and was found to be stronger in those not taking medication. PCA analysis revealed a single component indicating a greater level of general clinical symptoms. Neuroimaging findings would suggest that alterations in implicit emotion processing in AN occur during early perceptual processing of social signals and illustrate greater engagement on the FEPT. The lack of separate components using PCA suggests that the questionnaires used might not be suited as predictive measures.

  18. The Pro-inflammatory Effects of Glucocorticoids in the Brain

    PubMed Central

    Duque, Erica de Almeida; Munhoz, Carolina Demarchi

    2016-01-01

    Glucocorticoids are a class of steroid hormones derived from cholesterol. Their actions are mediated by the glucocorticoid and mineralocorticoid receptors, members of the superfamily of nuclear receptors, which, once bound to their ligands, act as transcription factors that can directly modulate gene expression. Through protein–protein interactions with other transcription factors, they can also regulate the activity of many genes in a composite or tethering way. Rapid non-genomic signaling was also demonstrated since glucocorticoids can act through membrane receptors and activate signal transduction pathways, such as protein kinases cascades, to modulate other transcriptions factors and activate or repress various target genes. By all these different mechanisms, glucocorticoids regulate numerous important functions in a large variety of cells, not only in the peripheral organs but also in the central nervous system during development and adulthood. In general, glucocorticoids are considered anti-inflammatory and protective agents due to their ability to inhibit gene expression of pro-inflammatory mediators and other possible damaging molecules. Nonetheless, recent studies have uncovered situations in which these hormones can act as pro-inflammatory agents depending on the dose, chronicity of exposure, and the structure/organ analyzed. In this review, we will provide an overview of the conditions under which these phenomena occur, a discussion that will serve as a basis for exploring the mechanistic foundation of glucocorticoids pro-inflammatory gene regulation in the brain. PMID:27445981

  19. Increased sensitivity of thyroid hormone-mediated signaling despite prolonged fasting.

    PubMed

    Martinez, Bridget; Scheibner, Michael; Soñanez-Organis, José G; Jaques, John T; Crocker, Daniel E; Ortiz, Rudy M

    2017-10-01

    Thyroid hormones (TH) can increase cellular metabolism. Food deprivation in mammals is typically associated with reduced thyroid gland responsiveness, in an effort to suppress cellular metabolism and abate starvation. However, in prolonged-fasted, elephant seal pups, cellular TH-mediated proteins are up-regulated and TH levels are maintained with fasting duration. The function and contribution of the thyroid gland to this apparent paradox is unknown and physiologically perplexing. Here we show that the thyroid gland remains responsive during prolonged food deprivation, and that its function and production of TH increase with fasting duration in elephant seals. We discovered that our modeled plasma TH data in response to exogenous thyroid stimulating hormone predicted cellular signaling, which was corroborated independently by the enzyme expression data. The data suggest that the regulation and function of the thyroid gland in the northern elephant seal is atypical for a fasted animal, and can be better described as, "adaptive fasting". Furthermore, the modeling data help substantiate the in vivo responses measured, providing unique insight on hormone clearance, production rates, and thyroid gland responsiveness. Because these unique endocrine responses occur simultaneously with a nearly strict reliance on the oxidation of lipid, these findings provide an intriguing model to better understand the TH-mediated reliance on lipid metabolism that is not otherwise present in morbidly obese humans. When coupled with cellular, tissue-specific responses, these data provide a more integrated assessment of thyroidal status that can be extrapolated for many fasting/food deprived mammals. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. Clarithromycin increases neuronal excitability in CA3 pyramidal neurons through a reduction in GABAergic signaling.

    PubMed

    Bichler, Edyta K; Elder, Courtney C; García, Paul S

    2017-01-01

    Antibiotics are used in the treatment and prevention of bacterial infections, but effects on neuron excitability have been documented. A recent study demonstrated that clarithromycin alleviates daytime sleepiness in hypersomnia patients (Trotti LM, Saini P, Freeman AA, Bliwise DL, García PS, Jenkins A, Rye DB. J Psychopharmacol 28: 697-702, 2014). To explore the potential application of clarithromycin as a stimulant, we performed whole cell patch-clamp recordings in rat pyramidal cells from the CA3 region of hippocampus. In the presence of the antibiotic, rheobase current was reduced by 50%, F-I relationship (number of action potentials as a function of injected current) was shifted to the left, and the resting membrane potential was more depolarized. Clarithromycin-induced hyperexcitability was dose dependent; doses of 30 and 300 μM clarithromycin significantly increased the firing frequency and membrane potential compared with controls (P = 0.003, P < 0.0001). We hypothesized that clarithromycin enhanced excitability by reducing GABAA receptor activation. Clarithromycin at 30 μM significantly reduced (P = 0.001) the amplitude of spontaneous miniature inhibitory GABAergic currents and at 300 μM had a minor effect on action potential width. Additionally, we tested the effect of clarithromycin in an ex vivo seizure model by evaluating its effect on spontaneous local field potentials. Bath application of 300 μM clarithromycin enhanced burst frequency twofold compared with controls (P = 0.0006). Taken together, these results suggest that blocking GABAergic signaling with clarithromycin increases cellular excitability and potentially serves as a stimulant, facilitating emergence from anesthesia or normalizing vigilance in hypersomnia and narcolepsy. However, the administration of clarithromycin should be carefully considered in patients with seizure disorders.

  1. Altered prostanoid signaling contributes to increased skin tumorigenesis in Tpl2 knockout mice.

    PubMed

    DeCicco-Skinner, Kathleen L; Nolan, Sabrina J; Deshpande, Monika M; Trovato, Erika L; Dempsey, Taylor A; Wiest, Jonathan S

    2013-01-01

    Squamous cell carcinoma is the second most common form of skin cancer with the incidence expected to double over the next 20 years. Inflammation is believed to be a critical component in skin cancer progression. Therefore, understanding genes involved in the regulation of inflammatory pathways is vital to the design of targeted therapies. Numerous studies show cyclooxygenases (COXs) play an essential role in inflammation-associated cancers. Tpl2 (MAP3K8) is a protein kinase in the MAP Kinase signal transduction cascade. Previous research using a two-stage skin carcinogenesis model revealed that Tpl2(-/-) mice have significantly higher tumor incidence and inflammatory response than wild-type (WT) controls. The current study investigates whether cyclooxygenase-2 (COX-2) and COX-2- regulated prostaglandins and prostaglandin receptors drive the highly tumorigenic state of Tpl2(-/-) mice by investigating the relationship between Tpl2 and COX-2. Keratinocytes from newborn WT or Tpl2(-/-) mice were treated with 12-O-tetradecanoylphorbol-13-acetate (TPA) for various times over 24 hours. Western analysis revealed significant differences in COX-2 and COX-2 dependent prostanoids and prostanoid receptors. Additionally, in vivo experiments confirmed that COX-2 and COX-2 downstream factors were elevated in TPA-treated Tpl2(-/-) skin, as well as in papillomas from Tpl2(-/-) mice. Use of the selective COX-2 inhibitor Celecoxib showed the increased tumorigenesis in the Tpl2(-/-) mice to primarily be mediated through COX-2. These experiments illustrate COX-2 induction in the absence of Tpl2 may be responsible for the increased tumorigenesis found in Tpl2(-/-) mice. Defining the relationship between Tpl2 and COX-2 may lead to new ways to downregulate COX-2 through the modulation of Tpl2.

  2. Caffeine increases mitochondrial function and blocks melatonin signaling to mitochondria in Alzheimer's mice and cells.

    PubMed

    Dragicevic, Natasa; Delic, Vedad; Cao, Chuanhai; Copes, Neil; Lin, Xiaoyang; Mamcarz, Maggie; Wang, Li; Arendash, Gary W; Bradshaw, Patrick C

    2012-12-01

    Caffeine and melatonin have been shown to protect the Swedish mutant amyloid precursor protein (APP(sw)) transgenic mouse model of Alzheimer's disease from cognitive dysfunction. But their mechanisms of action remain incompletely understood. These Alzheimer's mice have extensive mitochondrial dysfunction, which likely contributes to their cognitive decline. To further explore the mechanism through which caffeine and melatonin protect cognitive function in these mice, we monitored the function of isolated mitochondria from APP(sw) mice treated with caffeine, melatonin, or both in their drinking water for one month. Melatonin treatment yielded a near complete restoration of mitochondrial function in assays of respiratory rate, membrane potential, reactive oxygen species production, and ATP levels. Caffeine treatment by itself yielded a small increase in mitochondrial function. However, caffeine largely blocked the large enhancement of mitochondrial function provided by melatonin. Studies with N2a neuroblastoma cells stably expressing APP(sw) show