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Sample records for tgf-sz receptor promoter

  1. GABAA receptor-expressing neurons promote consumption in Drosophila melanogaster.

    Science.gov (United States)

    Cheung, Samantha K; Scott, Kristin

    2017-01-01

    Feeding decisions are highly plastic and bidirectionally regulated by neurons that either promote or inhibit feeding. In Drosophila melanogaster, recent studies have identified four GABAergic interneurons that act as critical brakes to prevent incessant feeding. These GABAergic neurons may inhibit target neurons that drive consumption. Here, we tested this hypothesis by examining GABA receptors and neurons that promote consumption. We find that Resistance to dieldrin (RDL), a GABAA type receptor, is required for proper control of ingestion. Knockdown of Rdl in a subset of neurons causes overconsumption of tastants. Acute activation of these neurons is sufficient to drive consumption of appetitive substances and non-appetitive substances and acute silencing of these neurons decreases consumption. Taken together, these studies identify GABAA receptor-expressing neurons that promote Drosophila ingestive behavior and provide insight into feeding regulation.

  2. 5-HT7 receptor activation promotes an increase in TrkB receptor expression and phosphorylation

    Directory of Open Access Journals (Sweden)

    Anshula eSamarajeewa

    2014-11-01

    Full Text Available The serotonin (5-HT type 7 receptor is expressed throughout the CNS including cortical neurons. We have previously demonstrated that the application of 5-HT7 receptor agonists to primary hippocampal neurons and SH-SY5Y cells increases platelet-derived growth factor (PDGF receptor expression and promotes neuroprotection against N-methyl-D-aspartate-(NMDA-induced toxicity. The tropomyosin-related kinase B (TrkB receptor is one of the receptors for brain-derived neurotrophic factor (BDNF and is associated with neurodevelopmental and neuroprotective effects. Application of LP 12 to primary cerebral cortical cultures, SH-SY5Y cells, as well as the retinal ganglion cell line, RGC-5, increased both the expression of full length TrkB as well as its basal phosphorylation state at tyrosine 816. The increase in TrkB expression and phosphorylation was observed as early as 30 min after 5-HT7 receptor activation. In addition to full-length TrkB, kinase domain-deficient forms may be expressed and act as dominant-negative proteins towards the full length receptor. We have identified distinct patterns of TrkB isoform expression across our cell lines and cortical cultures. Although TrkB receptor expression is regulated by cyclic AMP and Gαs-coupled GPCRs in several systems, we demonstrate that, depending on the model system, pathways downstream of both Gαs and Gα12 are involved in the regulation of TrkB expression by 5-HT7 receptors. Given the number of psychiatric and degenerative diseases associated with TrkB/BDNF deficiency and the current interest in developing 5-HT7 receptor ligands as pharmaceuticals, identifying signaling relationships between these two receptors will aid in our understanding of the potential therapeutic effects of 5-HT7 receptor ligands.

  3. Glycine Receptor α2 Subunit Activation Promotes Cortical Interneuron Migration

    Directory of Open Access Journals (Sweden)

    Ariel Avila

    2013-08-01

    Full Text Available Glycine receptors (GlyRs are detected in the developing CNS before synaptogenesis, but their function remains elusive. This study demonstrates that functional GlyRs are expressed by embryonic cortical interneurons in vivo. Furthermore, genetic disruption of these receptors leads to interneuron migration defects. We discovered that extrasynaptic activation of GlyRs containing the α2 subunit in cortical interneurons by endogenous glycine activates voltage-gated calcium channels and promotes calcium influx, which further modulates actomyosin contractility to fine-tune nuclear translocation during migration. Taken together, our data highlight the molecular events triggered by GlyR α2 activation that control cortical tangential migration during embryogenesis.

  4. Dual hypocretin receptor antagonism is more effective for sleep promotion than antagonism of either receptor alone.

    Directory of Open Access Journals (Sweden)

    Stephen R Morairty

    Full Text Available The hypocretin (orexin system is involved in sleep/wake regulation, and antagonists of both hypocretin receptor type 1 (HCRTR1 and/or HCRTR2 are considered to be potential hypnotic medications. It is currently unclear whether blockade of either or both receptors is more effective for promoting sleep with minimal side effects. Accordingly, we compared the properties of selective HCRTR1 (SB-408124 and SB-334867 and HCRTR2 (EMPA antagonists with that of the dual HCRTR1/R2 antagonist almorexant in the rat. All 4 antagonists bound to their respective receptors with high affinity and selectivity in vitro. Since in vivo pharmacokinetic experiments revealed poor brain penetration for SB-408124, SB-334867 was selected for subsequent in vivo studies. When injected in the mid-active phase, SB-334867 produced small increases in rapid-eye-movement (REM and non-REM (NR sleep. EMPA produced a significant increase in NR only at the highest dose studied. In contrast, almorexant decreased NR latency and increased both NR and REM proportionally throughout the subsequent 6 h without rebound wakefulness. The increased NR was due to a greater number of NR bouts; NR bout duration was unchanged. At the highest dose tested (100 mg/kg, almorexant fragmented sleep architecture by increasing the number of waking and REM bouts. No evidence of cataplexy was observed. HCRTR1 occupancy by almorexant declined 4-6 h post-administration while HCRTR2 occupancy was still elevated after 12 h, revealing a complex relationship between occupancy of HCRT receptors and sleep promotion. We conclude that dual HCRTR1/R2 blockade is more effective in promoting sleep than blockade of either HCRTR alone. In contrast to GABA receptor agonists which induce sleep by generalized inhibition, HCRTR antagonists seem to facilitate sleep by reducing waking "drive".

  5. The altered promoter methylation of oxytocin receptor gene in autism.

    Science.gov (United States)

    Elagoz Yuksel, Mine; Yuceturk, Betul; Karatas, Omer Faruk; Ozen, Mustafa; Dogangun, Burak

    Autism spectrum disorder (ASD) is one of the lifelong existing disorders. Abnormal methylation status of gene promoters of oxytonergic system has been implicated as among the etiologic factors of ASDs. We, therefore, investigated the methylation frequency of oxytocin receptor gene (OXTR) promoter from peripheral blood samples of children with autistic features. Our sample includes 66 children in total (22-94 months); 27 children with ASDs according to the DSM-IV-TR and the Childhood Autism Rating Scale (CARS) and 39 children who do not have any autistic like symptoms as the healthy control group. We investigated the DNA methylation status of OXTR promoter by methylation specific enzymatic digestion of genomic DNA and polymerase chain reaction. A significant relationship has been found between ASDs and healthy controls for the reduction of methylation frequency of the regions MT1 and MT3 of OXTR. We could not find any association in the methylation frequency of MT2 and MT4 regions of OXTR. Although our findings indicate high frequency of OXTR promoter hypomethylation in ASDs, there is need for independent replication of the results for a bigger sample set. We expect that future studies with the inclusion of larger, more homogeneous samples will attempt to disentangle the causes of ASDs.

  6. Selective androgen receptor modulators as function promoting therapies.

    Science.gov (United States)

    Bhasin, Shalender; Jasuja, Ravi

    2009-05-01

    The past decade has witnessed an unprecedented discovery effort to develop selective androgen receptor modulators (SARMs) that improve physical function and bone health without adversely affecting the prostate and cardiovascular outcomes. This review describes the historical evolution, the rationale for SARM development, and the mechanisms of testosterone action and SARM selectivity. Although steroidal SARMs have been around since the 1940s, a number of nonsteroidal SARMs that do not serve as substrates for CYP19 aromatase or 5alpha-reductase, act as full agonists in muscle and bone and as partial agonists in prostate are in development. The differing interactions of steroidal and nonsteroidal compounds with androgen receptor (AR) contribute to their unique pharmacologic actions. Ligand binding induces specific conformational changes in the ligand-binding domain, which could modulate surface topology and protein-protein interactions between AR and coregulators, resulting in tissue-specific gene regulation. Preclinical studies have demonstrated the ability of SARMs to increase muscle and bone mass in preclinical rodent models with varying degree of prostate sparing. Phase I trials of SARMs in humans have reported modest increments in fat-free mass. SARMs hold promise as a new class of function promoting anabolic therapies for a number of clinical indications, including functional limitations associated with aging and chronic disease, frailty, cancer cachexia, and osteoporosis.

  7. G protein-coupled receptor kinase 2 promotes cardiac hypertrophy

    Science.gov (United States)

    Tscheschner, Henrike; Gao, Erhe; Schumacher, Sarah M.; Yuan, Ancai; Backs, Johannes; Most, Patrick; Wieland, Thomas; Koch, Walter J.; Katus, Hugo A.; Raake, Philip W.

    2017-01-01

    The increase in protein activity and upregulation of G-protein coupled receptor kinase 2 (GRK2) is a hallmark of cardiac stress and heart failure. Inhibition of GRK2 improved cardiac function and survival and diminished cardiac remodeling in various animal heart failure models. The aim of the present study was to investigate the effects of GRK2 on cardiac hypertrophy and dissect potential molecular mechanisms. In mice we observed increased GRK2 mRNA and protein levels following transverse aortic constriction (TAC). Conditional GRK2 knockout mice showed attenuated hypertrophic response with preserved ventricular geometry 6 weeks after TAC operation compared to wild-type animals. In isolated neonatal rat ventricular cardiac myocytes stimulation with angiotensin II and phenylephrine enhanced GRK2 expression leading to enhanced signaling via protein kinase B (PKB or Akt), consecutively inhibiting glycogen synthase kinase 3 beta (GSK3β), such promoting nuclear accumulation and activation of nuclear factor of activated T-cells (NFAT). Cardiac myocyte hypertrophy induced by in vitro GRK2 overexpression increased the cytosolic interaction of GRK2 and phosphoinositide 3-kinase γ (PI3Kγ). Moreover, inhibition of PI3Kγ as well as GRK2 knock down prevented Akt activation resulting in halted NFAT activity and reduced cardiac myocyte hypertrophy. Our data show that enhanced GRK2 expression triggers cardiac hypertrophy by GRK2-PI3Kγ mediated Akt phosphorylation and subsequent inactivation of GSK3β, resulting in enhanced NFAT activity. PMID:28759639

  8. Selective Androgen Receptor Modulators (SARMs) as Function Promoting Therapies

    Science.gov (United States)

    Bhasin, Shalender; Jasuja, Ravi

    2010-01-01

    Purpose of review The last decade has witnessed unprecedented discovery effort to develop selective androgen receptor modulators (SARMs) that improve physical function and bone health without adversely affecting the prostate and cardiovascular outcomes. This review describes the historical evolution, the rationale for SARM development, and the mechanisms of testosterone action and SARM selectivity. Recent Findings While steroidal SARMs have been around since the 1940s, a number of nonsteroidal SARMs that do not serve as substrates for CYP19 aromatase or 5α-reductase, act as full agonists in muscle and bone and as partial agonists in prostate are in development. The differing interactions of steroidal and nonsteroidal compounds with AR contribute to their unique pharmacologic actions. Ligand binding induces specific conformational changes in the ligand binding domain, which could modulate surface topology and protein-protein interactions between AR and coregulators, resulting in tissue-specific gene regulation. Preclinical studies have demonstrated the ability of SARMs to increase muscle and bone mass in preclinical rodent models with varying degree of prostate sparing. Phase I trials of SARMs in humans have reported modest increments in fat-free mass. Summary SARMs hold promise as a new class of function promoting anabolic therapies for a number of clinical indications, including functional limitations associated with aging and chronic disease, frailty, cancer cachexia, and osteoporosis. PMID:19357508

  9. O-GlcNAcylation of Orphan Nuclear Receptor Estrogen-Related Receptor γ Promotes Hepatic Gluconeogenesis.

    Science.gov (United States)

    Misra, Jagannath; Kim, Don-Kyu; Jung, Yoon Seok; Kim, Han Byeol; Kim, Yong-Hoon; Yoo, Eun-Kyung; Kim, Byung Gyu; Kim, Sunghoon; Lee, In-Kyu; Harris, Robert A; Kim, Jeong-Sun; Lee, Chul-Ho; Cho, Jin Won; Choi, Hueng-Sik

    2016-10-01

    Estrogen-related receptor γ (ERRγ) is a major positive regulator of hepatic gluconeogenesis. Its transcriptional activity is suppressed by phosphorylation signaled by insulin in the fed state, but whether posttranslational modification alters its gluconeogenic activity in the fasted state is not known. Metabolically active hepatocytes direct a small amount of glucose into the hexosamine biosynthetic pathway, leading to protein O-GlcNAcylation. In this study, we demonstrate that ERRγ is O-GlcNAcylated by O-GlcNAc transferase in the fasted state. This stabilizes the protein by inhibiting proteasome-mediated protein degradation, increasing ERRγ recruitment to gluconeogenic gene promoters. Mass spectrometry identifies two serine residues (S317, S319) present in the ERRγ ligand-binding domain that are O-GlcNAcylated. Mutation of these residues destabilizes ERRγ protein and blocks the ability of ERRγ to induce gluconeogenesis in vivo. The impact of this pathway on gluconeogenesis in vivo was confirmed by the observation that decreasing the amount of O-GlcNAcylated ERRγ by overexpressing the deglycosylating enzyme O-GlcNAcase decreases ERRγ-dependent glucose production in fasted mice. We conclude that O-GlcNAcylation of ERRγ serves as a major signal to promote hepatic gluconeogenesis. © 2016 by the American Diabetes Association.

  10. Receptor protein tyrosine phosphatase alpha enhances rheumatoid synovial fibroblast signaling and promotes arthritis in mice

    NARCIS (Netherlands)

    Stanford, Stephanie M; Svensson, Mattias N D; Sacchetti, Cristiano; Pilo, Caila A; Wu, Dennis J; Kiosses, William B; Hellvard, Annelie; Bergum, Brith; Aleman Muench, German R; Elly, Christian; Liu, Yun-Cai; den Hertog, Jeroen; Elson, Ari; Sap, Jan; Mydel, Piotr; Boyle, David L; Corr, Maripat; Firestein, Gary S; Bottini, Nunzio

    2016-01-01

    OBJECTIVE: During rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLS) critically promote disease pathogenesis by aggressively invading the joint extracellular matrix. The focal adhesion kinase (FAK) signaling pathway is emerging as a contributor to RA FLS anomalous behavior. The receptor

  11. Dopamine receptor D4 promoter hypermethylation increases the risk of drug addiction

    OpenAIRE

    Ji, Huihui; Xu, Xuting; Liu, Guili; Liu, Huifen; Wang, Qinwen; Shen, Wenwen; Li, Longhui; Xie, Xiaohu; Hu, Haochang; Xu, Lei; Zhou, Wenhua; Duan, Shiwei

    2017-01-01

    Heroin and methylamphetamine (METH) are two addictive drugs that cause serious problems for society. Dopamine receptor D4 (DRD4), a key receptor in the dopaminergic system, may facilitate the development of drug addiction. The aim of the present study was to investigate the association between the promoter methylation level of DRD4 gene and drug addiction. Bisulfite pyrosequencing technology was used to measure the methylation levels of DRD4 promoter in 60 drug addicts and 52 matched controls...

  12. The axonal guidance receptor neogenin promotes acute inflammation.

    Directory of Open Access Journals (Sweden)

    Klemens König

    Full Text Available Neuronal guidance proteins (NGP were originally described in the context of axonal growth and migration. Yet recent work has demonstrated that NGPs also serve as guidance cues for immune competent cells. A crucial target receptor for NGPs during embryonic development is the neogenin receptor, however its role during acute inflammation is unknown. We report here that neogenin is abundantly expressed outside the nervous system and that animals with endogenous repression of neogenin (Neo1(-/- demonstrate attenuated changes of acute inflammation. Studies using functional inhibition of neogenin resulted in a significant attenuation of inflammatory peritonitis. In studies employing bone marrow chimeric animals we found the hematopoietic presence of Neo1(-/- to be responsible for the attenuated inflammatory response. Taken together our studies suggest that the guidance receptor neogenin holds crucial importance for the propagation of an acute inflammatory response and further define mechanisms shared between the nervous and the immune system.

  13. Activation of GLP-1 Receptor Promotes Bone Marrow Stromal Cell Osteogenic Differentiation through β-Catenin

    OpenAIRE

    Jingru Meng; Xue Ma; Ning Wang; Min Jia; Long Bi; Yunying Wang; Mingkai Li; Huinan Zhang; Xiaoyan Xue; Zheng Hou; Ying Zhou; Zhibin Yu; Gonghao He; Xiaoxing Luo

    2016-01-01

    Summary Glucagon-like peptide 1 (GLP-1) plays an important role in regulating bone remodeling, and GLP-1 receptor agonist shows a positive relationship with osteoblast activity. However, GLP-1 receptor is not found in osteoblast, and the mechanism of GLP-1 receptor agonist on regulating bone remodeling is unclear. Here, we show that the GLP-1 receptor agonist exendin-4 (Ex-4) promoted bone formation and increased bone mass and quality in a rat unloading-induced bone loss model. These function...

  14. Death Receptor 6 Promotes Wallerian Degeneration in Peripheral Axons.

    Science.gov (United States)

    Gamage, Kanchana K; Cheng, Irene; Park, Rachel E; Karim, Mardeen S; Edamura, Kazusa; Hughes, Christopher; Spano, Anthony J; Erisir, Alev; Deppmann, Christopher D

    2017-03-20

    Axon degeneration during development is required to sculpt a functional nervous system and is also a hallmark of pathological insult, such as injury [1, 2]. Despite similar morphological characteristics, very little overlap in molecular mechanisms has been reported between pathological and developmental degeneration [3-5]. In the peripheral nervous system (PNS), developmental axon pruning relies on receptor-mediated extrinsic degeneration mechanisms to determine which axons are maintained or degenerated [5-7]. Receptors have not been implicated in Wallerian axon degeneration; instead, axon autonomous, intrinsic mechanisms are thought to be the primary driver for this type of axon disintegration [8-10]. Here we survey the role of neuronally expressed, paralogous tumor necrosis factor receptor super family (TNFRSF) members in Wallerian degeneration. We find that an orphan receptor, death receptor 6 (DR6), is required to drive axon degeneration after axotomy in sympathetic and sensory neurons cultured in microfluidic devices. We sought to validate these in vitro findings in vivo using a transected sciatic nerve model. Consistent with the in vitro findings, DR6 -/- animals displayed preserved axons up to 4 weeks after injury. In contrast to phenotypes observed in Wld s and Sarm1 -/- mice, preserved axons in DR6 -/- animals display profound myelin remodeling. This indicates that deterioration of axons and myelin after axotomy are mechanistically distinct processes. Finally, we find that JNK signaling after injury requires DR6, suggesting a link between this novel extrinsic pathway and the axon autonomous, intrinsic pathways that have become established for Wallerian degeneration. Copyright © 2017 Elsevier Ltd. All rights reserved.

  15. Mesotocin and nonapeptide receptors promote estrildid flocking behavior.

    Science.gov (United States)

    Goodson, James L; Schrock, Sara E; Klatt, James D; Kabelik, David; Kingsbury, Marcy A

    2009-08-14

    Proximate neural mechanisms that influence preferences for groups of a given size are almost wholly unknown. In the highly gregarious zebra finch (Estrildidae: Taeniopygia guttata), blockade of nonapeptide receptors by an oxytocin (OT) antagonist significantly reduced time spent with large groups and familiar social partners independent of time spent in social contact. Opposing effects were produced by central infusions of mesotocin (MT, avian homolog of OT). Most drug effects appeared to be female-specific. Across five estrildid finch species, species-typical group size correlates with nonapeptide receptor distributions in the lateral septum, and sociality in female zebra finches was reduced by OT antagonist infusions into the septum but not a control area. We propose that titration of sociality by MT represents a phylogenetically deep framework for the evolution of OT's female-specific roles in pair bonding and maternal functions.

  16. Dioxin increases the interaction between aryl hydrocarbon receptor and estrogen receptor alpha at human promoters

    DEFF Research Database (Denmark)

    Ahmed, Shaaima; Valen, Eivind; Sandelin, Albin Gustav

    2009-01-01

    Recent studies have shown that activated aryl hydrocarbon receptor (AHR) induced the recruitment of estrogen receptor- (ER ) to AHR-regulated genes and that AHR is recruited to ER -regulated genes. However, these findings were limited to a small number of well-characterized AHR- or ER -responsive...

  17. Activation of GLP-1 Receptor Promotes Bone Marrow Stromal Cell Osteogenic Differentiation through β-Catenin

    Directory of Open Access Journals (Sweden)

    Jingru Meng

    2016-04-01

    Full Text Available Glucagon-like peptide 1 (GLP-1 plays an important role in regulating bone remodeling, and GLP-1 receptor agonist shows a positive relationship with osteoblast activity. However, GLP-1 receptor is not found in osteoblast, and the mechanism of GLP-1 receptor agonist on regulating bone remodeling is unclear. Here, we show that the GLP-1 receptor agonist exendin-4 (Ex-4 promoted bone formation and increased bone mass and quality in a rat unloading-induced bone loss model. These functions were accompanied by an increase in osteoblast number and serum bone formation markers, while the adipocyte number was decreased. Furthermore, GLP-1 receptor was detected in bone marrow stromal cells (BMSCs, but not in osteoblast. Activation of GLP-1 receptor by Ex-4 promoted the osteogenic differentiation and inhibited BMSC adipogenic differentiation through regulating PKA/β-catenin and PKA/PI3K/AKT/GSK3β signaling. These findings reveal that GLP-1 receptor regulates BMSC osteogenic differentiation and provide a molecular basis for therapeutic potential of GLP-1 against osteoporosis.

  18. Endothelial Cells Promote Pigmentation through Endothelin Receptor B Activation.

    Science.gov (United States)

    Regazzetti, Claire; De Donatis, Gian Marco; Ghorbel, Houda Hammami; Cardot-Leccia, Nathalie; Ambrosetti, Damien; Bahadoran, Philippe; Chignon-Sicard, Bérengère; Lacour, Jean-Philippe; Ballotti, Robert; Mahns, Andre; Passeron, Thierry

    2015-12-01

    Findings of increased vascularization in melasma lesions and hyperpigmentation in acquired bilateral telangiectatic macules suggested a link between pigmentation and vascularization. Using high-magnification digital epiluminescence dermatoscopy, laser confocal microscopy, and histological examination, we showed that benign vascular lesions of the skin have restricted but significant hyperpigmentation compared with the surrounding skin. We then studied the role of microvascular endothelial cells in regulating skin pigmentation using an in vitro co-culture model using endothelial cells and melanocytes. These experiments showed that endothelin 1 released by microvascular endothelial cells induces increased melanogenesis signaling, characterized by microphthalmia-associated transcription factor phosphorylation, and increased tyrosinase and dopachrome tautomerase levels. Immunostaining for endothelin 1 in vascular lesions confirmed the increased expression on the basal layer of the epidermis above small vessels compared with perilesional skin. Endothelin acts through the activation of endothelin receptor B and the mitogen-activated protein kinase, extracellular signal-regulated kinase (ERK)1/2, and p38, to induce melanogenesis. Finally, culturing of reconstructed skin with microvascular endothelial cells led to increased skin pigmentation that could be prevented by inhibiting EDNRB. Taken together these results demonstrated the role of underlying microvascularization in skin pigmentation, a finding that could open new fields of research for regulating physiological pigmentation and for treating pigmentation disorders such as melasma.

  19. B1 but not B2 bradykinin receptor agonists promote DU145 prostate ...

    African Journals Online (AJOL)

    Stimulation of G protein-coupled bradykinin receptors (BR), B1R and. B2R, mediate the effects of bradykinin (BK), which include promotion of cell growth, proliferation and. Corresponding author: Naidoo S. Discipline of Pharmaceutical Sciences,. School of Health Sciences, Nelson R. Mandela School of Medicine campus,.

  20. Immunomodulator CD200 promotes neurotrophic activity by interacting with and activating the fibroblast growth factor receptor

    DEFF Research Database (Denmark)

    Pankratova, Stanislava; Björnsdóttir, Halla; Christensen, Claus

    2016-01-01

    in the suppression of microglia activation. We for the first time demonstrated that CD200 can interact with and transduce signaling through activation of the fibroblast growth factor receptor (FGFR), thereby inducing neuritogenesis and promoting neuronal survival in primary neurons. CD200-induced FGFR...

  1. Multiple promoters drive tissue-specific expression of the human M2 muscarinic acetylcholine receptor gene

    Czech Academy of Sciences Publication Activity Database

    Krejčí, Alena; Bruce, A. W.; Doležal, Vladimír; Tuček, Stanislav; Buckley, N. J.

    2004-01-01

    Roč. 91, č. 1 (2004), s. 88-98 ISSN 0022-3042 R&D Projects: GA AV ČR IAA5011306 Institutional research plan: CEZ:AV0Z5011922 Keywords : M2 muscarinic receptor * neuron-restrictive silence factor * promoter Subject RIV: ED - Physiology Impact factor: 4.824, year: 2004

  2. RAGE is a nucleic acid receptor that promotes inflammatory responses to DNA

    Science.gov (United States)

    Sirois, Cherilyn M.; Jin, Tengchuan; Miller, Allison L.; Bertheloot, Damien; Nakamura, Hirotaka; Horvath, Gabor L.; Mian, Abubakar; Jiang, Jiansheng; Schrum, Jacob; Bossaller, Lukas; Pelka, Karin; Garbi, Natalio; Brewah, Yambasu; Tian, Jane; Chang, ChewShun; Chowdhury, Partha S.; Sims, Gary P.; Kolbeck, Roland; Coyle, Anthony J.; Humbles, Alison A.

    2013-01-01

    Recognition of DNA and RNA molecules derived from pathogens or self-antigen is one way the mammalian immune system senses infection and tissue damage. Activation of immune signaling receptors by nucleic acids is controlled by limiting the access of DNA and RNA to intracellular receptors, but the mechanisms by which endosome-resident receptors encounter nucleic acids from the extracellular space are largely undefined. In this study, we show that the receptor for advanced glycation end-products (RAGE) promoted DNA uptake into endosomes and lowered the immune recognition threshold for the activation of Toll-like receptor 9, the principal DNA-recognizing transmembrane signaling receptor. Structural analysis of RAGE–DNA complexes indicated that DNA interacted with dimers of the outermost RAGE extracellular domains, and could induce formation of higher-order receptor complexes. Furthermore, mice deficient in RAGE were unable to mount a typical inflammatory response to DNA in the lung, indicating that RAGE is important for the detection of nucleic acids in vivo. PMID:24081950

  3. EPO-independent functional EPO receptor in breast cancer enhances estrogen receptor activity and promotes cell proliferation

    International Nuclear Information System (INIS)

    Reinbothe, Susann; Larsson, Anna-Maria; Vaapil, Marica; Wigerup, Caroline; Sun, Jianmin; Jögi, Annika; Neumann, Drorit; Rönnstrand, Lars; Påhlman, Sven

    2014-01-01

    Highlights: • New anti-human EPOR antibody confirms full-length EPOR expression in breast cancer cells. • Proliferation of breast cancer cells is not affected by rhEPO treatment in vitro. • EPOR knockdown impairs proliferation of ERa positive breast cancer cells. • EPOR knockdown reduces AKT phosphorylation and ERa activity. - Abstract: The main function of Erythropoietin (EPO) and its receptor (EPOR) is the stimulation of erythropoiesis. Recombinant human EPO (rhEPO) is therefore used to treat anemia in cancer patients. However, clinical trials have indicated that rhEPO treatment might promote tumor progression and has a negative effect on patient survival. In addition, EPOR expression has been detected in several cancer forms. Using a newly produced anti-EPOR antibody that reliably detects the full-length isoform of the EPOR we show that breast cancer tissue and cells express the EPOR protein. rhEPO stimulation of cultured EPOR expressing breast cancer cells did not result in increased proliferation, overt activation of EPOR (receptor phosphorylation) or a consistent activation of canonical EPOR signaling pathway mediators such as JAK2, STAT3, STAT5, or AKT. However, EPOR knockdown experiments suggested functional EPO receptors in estrogen receptor positive (ERα + ) breast cancer cells, as reduced EPOR expression resulted in decreased proliferation. This effect on proliferation was not seen in ERα negative cells. EPOR knockdown decreased ERα activity further supports a mechanism by which EPOR affects proliferation via ERα-mediated mechanisms. We show that EPOR protein is expressed in breast cancer cells, where it appears to promote proliferation by an EPO-independent mechanism in ERα expressing breast cancer cells

  4. EPO-independent functional EPO receptor in breast cancer enhances estrogen receptor activity and promotes cell proliferation

    Energy Technology Data Exchange (ETDEWEB)

    Reinbothe, Susann; Larsson, Anna-Maria; Vaapil, Marica; Wigerup, Caroline [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Sun, Jianmin [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); Jögi, Annika [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Neumann, Drorit [Department of Cell and Developmental Biology, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel); Rönnstrand, Lars [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); Påhlman, Sven, E-mail: sven.pahlman@med.lu.se [Department of Laboratory Medicine, Translational Cancer Research, Medicon Village, Lund University, SE-223 81 Lund (Sweden); CREATE Health, Sackler Faculty of Medicine, Tel-Aviv University, Tel-Aviv (Israel)

    2014-02-28

    Highlights: • New anti-human EPOR antibody confirms full-length EPOR expression in breast cancer cells. • Proliferation of breast cancer cells is not affected by rhEPO treatment in vitro. • EPOR knockdown impairs proliferation of ERa positive breast cancer cells. • EPOR knockdown reduces AKT phosphorylation and ERa activity. - Abstract: The main function of Erythropoietin (EPO) and its receptor (EPOR) is the stimulation of erythropoiesis. Recombinant human EPO (rhEPO) is therefore used to treat anemia in cancer patients. However, clinical trials have indicated that rhEPO treatment might promote tumor progression and has a negative effect on patient survival. In addition, EPOR expression has been detected in several cancer forms. Using a newly produced anti-EPOR antibody that reliably detects the full-length isoform of the EPOR we show that breast cancer tissue and cells express the EPOR protein. rhEPO stimulation of cultured EPOR expressing breast cancer cells did not result in increased proliferation, overt activation of EPOR (receptor phosphorylation) or a consistent activation of canonical EPOR signaling pathway mediators such as JAK2, STAT3, STAT5, or AKT. However, EPOR knockdown experiments suggested functional EPO receptors in estrogen receptor positive (ERα{sup +}) breast cancer cells, as reduced EPOR expression resulted in decreased proliferation. This effect on proliferation was not seen in ERα negative cells. EPOR knockdown decreased ERα activity further supports a mechanism by which EPOR affects proliferation via ERα-mediated mechanisms. We show that EPOR protein is expressed in breast cancer cells, where it appears to promote proliferation by an EPO-independent mechanism in ERα expressing breast cancer cells.

  5. Activation of dopamine receptors in the nucleus accumbens promotes sucrose-reinforced cued approach behavior

    Directory of Open Access Journals (Sweden)

    Saleem M. Nicola

    2016-07-01

    Full Text Available Dopamine receptor activation in the nucleus accumbens (NAc promotes vigorous environmentally-cued food-seeking in hungry rats. Rats fed ad libitum, however, respond to fewer food-predictive cues, particularly when the value of food reward is low. Here, we investigated whether this difference could be due to differences in the degree of dopamine receptor activation in the NAc. First, we observed that although rats given ad libitum access to chow in their home cages approached a food receptacle in response to reward-predictive cues, the number of such approaches declined as animals accumulated food rewards. Intriguingly, cued approach to food occurred in clusters, with several cued responses followed by successive non-responses. This pattern suggested that behavior was dictated by transitions between two states, responsive and non-responsive. Injection of D1 or D2 dopamine receptor agonists into the NAc dose-dependently increased cue responding by promoting transitions to the responsive state and by preventing transitions to the non-responsive state. In contrast, antagonists of either D1 or D2 receptors promoted long bouts of non-responding by inducing transitions to the non-responsive state and by preventing transitions to the responsive state. Moreover, locomotor behavior during the inter-trial interval was correlated with the responsive state, and was also increased by dopamine receptor agonists. These results suggest that activation of NAc dopamine receptors plays an important role in regulating the probability of approach to food under conditions of normative satiety.

  6. Characterization and functional analyses of the human G protein-coupled receptor kinase 4 gene promoter.

    Science.gov (United States)

    Hasenkamp, Sandra; Telgmann, Ralph; Staessen, Jan A; Hagedorn, Claudia; Dördelmann, Corinna; Bek, Martin; Brand-Herrmann, Stefan-Martin; Brand, Eva

    2008-10-01

    The G protein-coupled receptor kinase 4 is involved in renal sodium handling and blood pressure regulation. Missense variants have already been tested functionally and are associated with hypertension, but no data on promoter analyses are yet available. We scanned 94 hypertensive white subjects for genetic variation and performed promoter reporter gene analyses in HEK293T, COS7, and SaOs-2 cells. Transient transfections with various full lengths and wild-type deletion constructs revealed that 1851 bp of the flanking region and 275 bp of the 5'-untranslated region were sufficient for transcriptional activities and composed a powerful cis-active element in the distal 293 bp. The -1702T and +2T alleles resulted in drastic general reductions of promoter function, whereas an activity increasing effect of +268C was cell type specific. Electrophoretic mobility-shift assay, supershift, and cotransfection analyses of transcription factor binding sites predicted in silico (Alibaba2.1/Transfac7) resulted in allele-specific binding patterns of nuclear proteins and identified the participation of CCAAT/enhancer-binding protein transcription factor family members. The G protein-coupled receptor kinase 4 core promoter resides in the first 1851 bp upstream of its transcription start site. The 4 identified genetic variants within this region exert allele-specific impact on both cell type- and stimulation-dependent transcription and may affect the expression balance of renal G protein-coupled receptor kinase 4.

  7. Ferristatin II promotes degradation of transferrin receptor-1 in vitro and in vivo.

    Directory of Open Access Journals (Sweden)

    Shaina L Byrne

    Full Text Available Previous studies have shown that the small molecule iron transport inhibitor ferristatin (NSC30611 acts by down-regulating transferrin receptor-1 (TfR1 via receptor degradation. In this investigation, we show that another small molecule, ferristatin II (NSC8679, acts in a similar manner to degrade the receptor through a nystatin-sensitive lipid raft pathway. Structural domains of the receptor necessary for interactions with the clathrin pathway do not appear to be necessary for ferristatin II induced degradation of TfR1. While TfR1 constitutively traffics through clathrin-mediated endocytosis, with or without ligand, the presence of Tf blocked ferristatin II induced degradation of TfR1. This effect of Tf was lost in a ligand binding receptor mutant G647A TfR1, suggesting that Tf binding to its receptor interferes with the drug's activity. Rats treated with ferristatin II have lower TfR1 in liver. These effects are associated with reduced intestinal (59Fe uptake, lower serum iron and transferrin saturation, but no change in liver non-heme iron stores. The observed hypoferremia promoted by degradation of TfR1 by ferristatin II appears to be due to induced hepcidin gene expression.

  8. Class A scavenger receptor promotes osteoclast differentiation via the enhanced expression of receptor activator of NF-{kappa}B (RANK)

    Energy Technology Data Exchange (ETDEWEB)

    Takemura, Kenichi [Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Department of Orthopaedic and Neuro-Musculoskeletal Surgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto (Japan); Sakashita, Naomi; Fujiwara, Yukio; Komohara, Yoshihiro; Lei, XiaoFeng; Ohnishi, Koji [Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan); Suzuki, Hiroshi [National Research Center for Protozoan Diseases, Obihiro University of Agriculture and Veterinary Medicine, Hokkaido (Japan); Kodama, Tatsuhiko [Department of Molecular Biology and Medicine, Research Center for Advanced Science and Technology, The University of Tokyo, Tokyo (Japan); Mizuta, Hiroshi [Department of Orthopaedic and Neuro-Musculoskeletal Surgery, Graduate School of Medical Sciences, Kumamoto University, Kumamoto (Japan); Takeya, Motohiro, E-mail: takeya@kumamoto-u.ac.jp [Department of Cell Pathology, Graduate School of Medical Sciences, Kumamoto University, 1-1-1 Honjo, Kumamoto 860-8556 (Japan)

    2010-01-22

    Osteoclasts originate from bone marrow monocyte/macrophage lineage cells, and their differentiation depends on macrophage colony-stimulating factor (M-CSF) and receptor activator nuclear factor kappa B (RANK) ligand. Class A scavenger receptor (SR-A) is one of the principal functional molecules of macrophages, and its level of expression declines during osteoclast differentiation. To investigate the role of SR-A in osteoclastogenesis, we examined pathological changes in femoral bone and the expression levels of osteoclastogenesis-related molecules in SR-A{sup -/-} mice. The femoral osseous density of SR-A{sup -/-} mice was higher than that of SR-A{sup +/+} mice, and the number of multinucleated osteoclasts was significantly decreased. An in vitro differentiation assay revealed that the differentiation of multinucleated osteoclasts from bone marrow-derived progenitor cells is impaired in SR-A{sup -/-} mice. Elimination of SR-A did not alter the expression level of the M-CSF receptor, c-fms; however, the expression levels of RANK and RANK-related osteoclast-differentiation molecules such as nuclear factor of activated T-cells, cytoplasmic, calcineurin-dependent 1 (NFATc1) and microphthalmia-associated transcription factor (MITF) significantly decreased. Furthermore, acetylated low-density lipoprotein (AcLDL), an SR-A ligand, significantly increased the expression level of RANK and MITF during osteoclast differentiation. These data indicate that SR-A promotes osteoclastogenesis via augmentation of the expression level of RANK and its related molecules.

  9. Seminal Plasma Proteins as Androgen Receptor Coregulators Promote Prostate Cancer Growth

    Science.gov (United States)

    2014-10-01

    the presence of zinc was found to induce androgen-mediated PSA expression in AR-positive prostate cancer cells. Reportable Outcomes Ishiguro ...prostatectomy. Hum Pathol 43: 6 1991–2000, 2012. Appendix Ishiguro H, Izumi K, Zheng Y, Kashiwagi E, Kawahara T, Miyamoto H: Semenogelin I promotes...PROSTATE CANCER CELL GROWTH VIA FUNCTIONING AS AN ANDROGEN RECEPTOR COACTIVATOR AND PROTECTING AGAINST ZINC CYTOTOXICITY Hitoshi Ishiguro *, Baltimore

  10. Galanin and its receptor system promote the repair of injured sciatic nerves in diabetic rats

    Directory of Open Access Journals (Sweden)

    Xiao-feng Xu

    2016-01-01

    Full Text Available Various studies have reported that galanin can promote axonal regeneration of dorsal root ganglion neurons in vitro and inhibit neuropathic pain. However, little is known about its effects on diabetic peripheral neuropathy, and in vivo experimental data are lacking. We hypothesized that repeated applications of exogenous galanin over an extended time frame may also repair nerve damage in diabetic peripheral neuropathy, and relieve pain in vivo. We found that neuropathic pain occurred in streptozotocin-induced diabetic rats and was more severe after sciatic nerve pinch injury at 14 and 28 days than in diabetic sham-operated rats. Treatment with exogenous galanin alleviated the neuropathic pain and promoted sciatic nerve regeneration more effectively in diabetic rats than in non-diabetic rats after sciatic nerve pinch injury. This was accompanied by changes in the levels of endogenous galanin, and its receptors galanin receptor 1 and galanin receptor 2 in the dorsal root ganglia and the spinal dorsal horn when compared with nerve pinch normal rats. Our results show that application of exogenous galanin daily for 28 days can promote the regeneration of injured sciatic nerves, and alleviate neuropathic pain in diabetic rats.

  11. Characterization of promoter sequence of toll-like receptor genes in Vechur cattle

    Directory of Open Access Journals (Sweden)

    R. Lakshmi

    2016-06-01

    Full Text Available Aim: To analyze the promoter sequence of toll-like receptor (TLR genes in Vechur cattle, an indigenous breed of Kerala with the sequence of Bos taurus and access the differences that could be attributed to innate immune responses against bovine mastitis. Materials and Methods: Blood samples were collected from Jugular vein of Vechur cattle, maintained at Vechur cattle conservation center of Kerala Veterinary and Animal Sciences University, using an acid-citrate-dextrose anticoagulant. The genomic DNA was extracted, and polymerase chain reaction was carried out to amplify the promoter region of TLRs. The amplified product of TLR2, 4, and 9 promoter regions was sequenced by Sanger enzymatic DNA sequencing technique. Results: The sequence of promoter region of TLR2 of Vechur cattle with the B. taurus sequence present in GenBank showed 98% similarity and revealed variants for four sequence motifs. The sequence of the promoter region of TLR4 of Vechur cattle revealed 99% similarity with that of B. taurus sequence but not reveals significant variant in motifregions. However, two heterozygous loci were observed from the chromatogram. Promoter sequence of TLR9 gene also showed 99% similarity to B. taurus sequence and revealed variants for four sequence motifs. Conclusion: The results of this study indicate that significant variation in the promoter of TLR2 and 9 genes in Vechur cattle breed and may potentially link the influence the innate immunity response against mastitis diseases.

  12. Multiple phosphorylation events control chicken ovalbumin upstream promoter transcription factor I orphan nuclear receptor activity.

    Science.gov (United States)

    Gay, Frédérique; Baráth, Peter; Desbois-Le Péron, Christine; Métivier, Raphaël; Le Guével, Rémy; Birse, Darcy; Salbert, Gilles

    2002-06-01

    Chicken ovalbumin upstream promoter transcription factor I (COUP-TFI) is an orphan member of the nuclear hormone receptor superfamily that comprises key regulators of many biological functions, such as embryonic development, metabolism, homeostasis, and reproduction. Although COUP-TFI can both actively silence gene transcription and antagonize the functions of various other nuclear receptors, the COUP-TFI orphan receptor also acts as a transcriptional activator in certain contexts. Moreover, COUP-TFI has recently been shown to serve as an accessory factor for some ligand-bound nuclear receptors, suggesting that it may modulate, both negatively and positively, a wide range of hormonal responses. In the absence of any identified cognate ligand, the mechanisms involved in the regulation of COUP-TFI activity remain unclear. The elucidation of several putative phosphorylation sites for MAPKs, PKC, and casein kinase II within the sequence of this orphan receptor led us to investigate phosphorylation events regulating the various COUP-TFI functions. After showing that COUP-TFI is phosphorylated in vivo, we provide evidence that in vivo inhibition of either MAPK or PKC signaling pathway leads to a specific and pronounced decrease in COUP-TFI-dependent transcriptional activation of the vitronectin gene promoter. Focusing on the molecular mechanisms underlying the MAPK- and PKC-mediated regulation of COUP-TFI activity, we show that COUP-TFI can be directly targeted by PKC and MAPK. These phosphorylation events differentially modulate COUP-TFI functions: PKC-mediated phosphorylation enhances COUP-TFI affinity for DNA and MAPK-mediated phosphorylation positively regulates the transactivation function of COUP-TFI, possibly through enhancing specific coactivator recruitment. These data provide evidence that COUP-TFI is likely to integrate distinct signaling pathways and raise the possibility that multiple extracellular signals influence biological processes controlled by COUP-TFI.

  13. CD36 and Platelet-Activating Factor Receptor Promote House Dust Mite Allergy Development.

    Science.gov (United States)

    Patel, Preeyam S; Kearney, John F

    2017-08-01

    Over 89% of asthmatic children in underdeveloped countries demonstrate sensitivity to house dust mites (HDMs). The allergic response to HDMs is partially mediated by epithelial cell-derived cytokines that activate group 2 innate lymphoid cells, induce migration and activation of dendritic cells, and promote effector differentiation of HDM-specific TH2 cells. However, the contribution of innate receptor engagement on epithelial or dendritic cells by HDMs that ultimately mediates said innate and adaptive allergic responses is poorly understood. We and other investigators have demonstrated that HDMs express phosphorylcholine (PC) moieties. The major PC receptors involved in immune responses include CD36 and platelet-activating factor receptor (PAFR). Because CD36 and PAFR are expressed by epithelial cells and dendritic cells, and expression of these receptors is higher in human asthmatics, we determined whether engagement of CD36 or PAFR on epithelial or dendritic cells contributes to HDM allergy development. Testing bone marrow chimeric mice revealed that CD36 engagement on radioresistant cells and PAFR engagement on radioresistant and radiosensitive cells in the lung promote allergic responses to HDMs. Additionally, passive anti-PC IgM Abs administered intratracheally with HDMs decreased allergen uptake by epithelial cells and APCs in the lungs of C57BL/6 mice but not CD36 -/- or PAFR -/- mice. These results show that CD36 and PAFR are important mediators of HDM allergy development and that inhibiting HDM engagement with PC receptors in the lung protects against allergic airway disease. Copyright © 2017 by The American Association of Immunologists, Inc.

  14. GABA agonist promoted formation of low affinity GABA receptors on cerebellar granule cells is restricted to early development

    DEFF Research Database (Denmark)

    Belhage, B; Hansen, Gert Helge; Schousboe, A

    1988-01-01

    The ability of the GABA receptor agonist 4,5,6,7-tetrahydroisoxazolo[5,4-c]pyridin-3-ol (THIP) to promote formation of low affinity GABA receptors on cerebellar granule cells was tested using primary cultures of these neurons. Granule cells were exposed to THIP (150 microM) for 6 hr after......, respectively, 4, 7, 10 and 14 days in culture. It was found that THIP treatment of 4- and 7-day-old cultures led to formation of low affinity GABA receptors, whereas such receptors could not be detected after THIP treatment in the older cultures (10 and 14 days) in spite of the fact that these cultured granule...... cells expressed a high density of high affinity GABA receptors. It is concluded that the ability of THIP to promote formation of low affinity GABA receptors on cerebellar granule cells is restricted to an early developmental period....

  15. P2X7R suppression promotes glioma growth through epidermal growth factor receptor signal pathway.

    Science.gov (United States)

    Fang, Jingqin; Chen, Xiao; Zhang, Letian; Chen, Jinhua; Liang, Yi; Li, Xue; Xiang, Jianbo; Wang, Lili; Guo, Guangkuo; Zhang, Bo; Zhang, Weiguo

    2013-06-01

    P2X7 receptor (P2X7R) has been shown to mediate an anticancer effect via apoptosis in different types of cancer. However, whether P2X7R exerts a promoting or suppressive effect on brain glioma is still a controversial issue and its underlying mechanism remains unknown. We showed here that P2X7R suppression exerted a pro-growth effect on glioma through directly promoting cells proliferation and pro-angiogenesis, which was associated with epidermal growth factor receptor (EGFR) signaling. The P2X7R was markedly downregulated by cells exposure to the P2X7R antagonist, brilliant blue G (BBG), moreover, the cells proliferation was enhanced in a dose-dependent manner and the expression of EGFR or p-EGFR protein was significantly upregulated. By constructing C6 cells with reduced expression of P2X7R using shRNA, we also demonstrated strong upregulation in cells proliferation and EGFR/p-EGFR expression. However, this effect of BBG was reversed in the presence of gefitinib or suramin. Magnetic resonance imaging and computed tomography perfusion showed that the BBG or P2X7R shRNA promoted the tumor growth by about 40% and 50%, respectively, and significantly increased angiogenesis. Nissl and Ki-67 staining also confirmed that BBG or P2X7R shRNA notably increased the tumor growth. More importantly, either BBG or P2X7R shRNA could markedly upregulated the expression of EGFR, p-EGFR, HIF-1α and VEGF in glioma cells. In conclusion, P2X7R suppression exerts a promoting effect on glioma growth, which is likely to be related to upregulated EGFR, HIF-1α and VEGF expression. These findings provide important clues to the molecular basis of anticancer effect of targeting purinergic receptors. Copyright © 2013 Elsevier Ltd. All rights reserved.

  16. Dopamine receptor D4 promoter hypermethylation increases the risk of drug addiction.

    Science.gov (United States)

    Ji, Huihui; Xu, Xuting; Liu, Guili; Liu, Huifen; Wang, Qinwen; Shen, Wenwen; Li, Longhui; Xie, Xiaohu; Hu, Haochang; Xu, Lei; Zhou, Wenhua; Duan, Shiwei

    2018-02-01

    Heroin and methylamphetamine (METH) are two addictive drugs that cause serious problems for society. Dopamine receptor D4 (DRD4), a key receptor in the dopaminergic system, may facilitate the development of drug addiction. The aim of the present study was to investigate the association between the promoter methylation level of DRD4 gene and drug addiction. Bisulfite pyrosequencing technology was used to measure the methylation levels of DRD4 promoter in 60 drug addicts and 52 matched controls. Significantly higher levels of DRD4 CpG1 and CpG4 methylation were detected in METH and heroin drug addicts compared with controls (Paddicts exhibited significantly higher DRD4 CpG1, CpG2 and CpG4 methylation levels compared with sex-matched controls (Paddicts, a positive correlation was observed between depression-dejection and DRD4 CpG5 methylation (r=0.537, P=0.039) whereas there was a negative correlation between drug usage frequency and CpG1 methylation (r=-0.632, P=0.011). In METH addicts, methylation levels were not significantly associated with depression-dejection and drug usage frequency. In addition, luciferase assays demonstrated that the target sequence of the DRD4 promoter upregulates gene expression. The results of the present study suggest that DNA methylation of DRD4 may be responsible for the pathophysiology of drug addiction.

  17. DNA methylation of specific CpG sites in the promoter region regulates the transcription of the mouse oxytocin receptor.

    Directory of Open Access Journals (Sweden)

    Shimrat Mamrut

    Full Text Available Oxytocin is a peptide hormone, well known for its role in labor and suckling, and most recently for its involvement in mammalian social behavior. All central and peripheral actions of oxytocin are mediated through the oxytocin receptor, which is the product of a single gene. Transcription of the oxytocin receptor is subject to regulation by gonadal steroid hormones, and is profoundly elevated in the uterus and mammary glands during parturition. DNA methylation is a major epigenetic mechanism that regulates gene transcription, and has been linked to reduced expression of the oxytocin receptor in individuals with autism. Here, we hypothesized that transcription of the mouse oxytocin receptor is regulated by DNA methylation of specific sites in its promoter, in a tissue-specific manner. Hypothalamus-derived GT1-7, and mammary-derived 4T1 murine cell lines displayed negative correlations between oxytocin receptor transcription and methylation of the gene promoter, and demethylation caused a significant enhancement of oxytocin receptor transcription in 4T1 cells. Using a reporter gene assay, we showed that methylation of specific sites in the gene promoter, including an estrogen response element, significantly inhibits transcription. Furthermore, methylation of the oxytocin receptor promoter was found to be differentially correlated with oxytocin receptor expression in mammary glands and the uterus of virgin and post-partum mice, suggesting that it plays a distinct role in oxytocin receptor transcription among tissues and under different physiological conditions. Together, these results support the hypothesis that the expression of the mouse oxytocin receptor gene is epigenetically regulated by DNA methylation of its promoter.

  18. The Shh receptor Boc promotes progression of early medulloblastoma to advanced tumors.

    Science.gov (United States)

    Mille, Frédéric; Tamayo-Orrego, Lukas; Lévesque, Martin; Remke, Marc; Korshunov, Andrey; Cardin, Julie; Bouchard, Nicolas; Izzi, Luisa; Kool, Marcel; Northcott, Paul A; Taylor, Michael D; Pfister, Stefan M; Charron, Frédéric

    2014-10-13

    During cerebellar development, Sonic hedgehog (Shh) signaling drives the proliferation of granule cell precursors (GCPs). Aberrant activation of Shh signaling causes overproliferation of GCPs, leading to medulloblastoma. Although the Shh-binding protein Boc associates with the Shh receptor Ptch1 to mediate Shh signaling, whether Boc plays a role in medulloblastoma is unknown. Here, we show that BOC is upregulated in medulloblastomas and induces GCP proliferation. Conversely, Boc inactivation reduces proliferation and progression of early medulloblastomas to advanced tumors. Mechanistically, we find that Boc, through elevated Shh signaling, promotes high levels of DNA damage, an effect mediated by CyclinD1. High DNA damage in the presence of Boc increases the incidence of Ptch1 loss of heterozygosity, an important event in the progression from early to advanced medulloblastoma. Together, our results indicate that DNA damage promoted by Boc leads to the demise of its own coreceptor, Ptch1, and consequently medulloblastoma progression. Copyright © 2014 Elsevier Inc. All rights reserved.

  19. Macropinocytosis of the PDGF β-receptor promotes fibroblast transformation by H-RasG12V.

    Science.gov (United States)

    Schmees, C; Villaseñor, R; Zheng, W; Ma, H; Zerial, M; Heldin, C-H; Hellberg, C

    2012-07-01

    Receptor tyrosine kinase (RTK) signaling is frequently increased in tumor cells, sometimes as a result of decreased receptor down-regulation. The extent to which the endocytic trafficking routes can contribute to such RTK hyperactivation is unclear. Here, we show for the first time that fibroblast transformation by H-RasG12V induces the internalization of platelet-derived growth factor β-receptor (PDGFRβ) by macropinocytosis, enhancing its signaling activity and increasing anchorage-independent proliferation. H-RasG12V transformation and PDGFRβ activation were synergistic in stimulating phosphatidylinositol (PI) 3-kinase activity, leading to receptor macropinocytosis. PDGFRβ macropinocytosis was both necessary and sufficient for enhanced receptor activation. Blocking macropinocytosis by inhibition of PI 3-kinase prevented the increase in receptor activity in transformed cells. Conversely, increasing macropinocytosis by Rabankyrin-5 overexpression was sufficient to enhance PDGFRβ activation in nontransformed cells. Simultaneous stimulation with PDGF-BB and epidermal growth factor promoted macropinocytosis of both receptors and increased their activation in nontransformed cells. We propose that H-Ras transformation promotes tumor progression by enhancing growth factor receptor signaling as a result of increased receptor macropinocytosis.

  20. Structure of the gene for human β2-adrenergic receptor: expression and promoter characterization

    International Nuclear Information System (INIS)

    Emorine, L.J.; Marullo, S.; Delavier-Klutchko, C.; Kaveri, S.V.; Durieu-Trautmann, O.; Strosberg, A.D.

    1987-01-01

    The genomic gene coding for the human β 2 -adrenergic receptor (β 2 AR) from A431 epidermoid cells has been isolated. Transfection of the gene into eukaryotic cells restores a fully active receptor/GTP-binding protein/adenylate cyclase complex with β 2 AR properties. Southern blot analyses with β 2 AR-specific probes show that a single β 2 AR gene is common to various human tissues and that its flanking sequences are highly conserved among humans and between man and rabbit, mouse, and hamster. Functional significance of these regions is supported by the presence of a promoter region (including mRNA cap sites, two TATA boxes, a CAAT box, and three G + C-rich regions that resemble binding sites for transcription factor Sp1) 200-300 base pairs 5' to the translation initiation codon. In the 3' flanking region, sequences homologous to glucocorticoid-response elements might be responsible for the increased expression of the β 2 AR gene observed after treatment of the transfected cells with hydrocortisone. In addition, 5' to the promoter region, an open reading frame encodes a 251-residue polypeptide that displays striking homologies with protein kinases and other nucleotide-binding proteins

  1. Functionality of promoter microsatellites of arginine vasopressin receptor 1A (AVPR1A): implications for autism

    LENUS (Irish Health Repository)

    Tansey, Katherine E

    2011-03-31

    Abstract Background Arginine vasopressin (AVP) has been hypothesized to play a role in aetiology of autism based on a demonstrated involvement in the regulation of social behaviours. The arginine vasopressin receptor 1A gene (AVPR1A) is widely expressed in the brain and is considered to be a key receptor for regulation of social behaviour. Moreover, genetic variation at AVPR1A has been reported to be associated with autism. Evidence from non-human mammals implicates variation in the 5\\'-flanking region of AVPR1A in variable gene expression and social behaviour. Methods We examined four tagging single nucleotide polymorphisms (SNPs) (rs3803107, rs1042615, rs3741865, rs11174815) and three microsatellites (RS3, RS1 and AVR) at the AVPR1A gene for association in an autism cohort from Ireland. Two 5\\'-flanking region polymorphisms in the human AVPR1A, RS3 and RS1, were also tested for their effect on relative promoter activity. Results The short alleles of RS1 and the SNP rs11174815 show weak association with autism in the Irish population (P = 0.036 and P = 0.008, respectively). Both RS1 and RS3 showed differences in relative promoter activity by length. Shorter repeat alleles of RS1 and RS3 decreased relative promoter activity in the human neuroblastoma cell line SH-SY5Y. Conclusions These aligning results can be interpreted as a functional route for this association, namely that shorter alleles of RS1 lead to decreased AVPR1A transcription, which may proffer increased susceptibility to the autism phenotype.

  2. Mutation of the SHP-2 binding site in growth hormone (GH) receptor prolongs GH-promoted tyrosyl phosphorylation of GH receptor, JAK2, and STAT5B

    DEFF Research Database (Denmark)

    Stofega, M R; Herrington, J; Billestrup, Nils

    2000-01-01

    Binding of GH to GH receptor (GHR) rapidly and transiently activates multiple signal transduction pathways that contribute to the growth-promoting and metabolic effects of GH. While the events that initiate GH signal transduction, such as activation of the Janus tyrosine kinase JAK2, are beginnin...

  3. Liver Tumor Promotion by 2,3,7,8-Tetrachlorodibenzo-p-dioxin Is Dependent on the Aryl Hydrocarbon Receptor and TNF/IL-1 Receptors

    Science.gov (United States)

    Kennedy, Gregory D.; Nukaya, Manabu; Moran, Susan M.; Glover, Edward; Weinberg, Samuel; Balbo, Silvia; Hecht, Stephen S.; Pitot, Henry C.; Drinkwater, Norman R.; Bradfield, Christopher A.

    2014-01-01

    We set out to better understand the signal transduction pathways that mediate liver tumor promotion by 2,3,7,8-tetrachlorodibenzo-p-dioxn (“dioxin”). To this end, we first employed congenic mice homozygous for either the Ahrb1 or Ahrd alleles (encoding an aryl hydrocarbon receptor (AHR) with high or low binding affinity for dioxin, respectively) and demonstrated that hepatocellular tumor promotion in response to dioxin segregated with the Ahr locus. Once we had genetic evidence for the importance of AHR signaling, we then asked if tumor promotion by dioxin was influenced by “interleukin-1 (IL-1)-like” inflammatory cytokines. The importance of this question arose from our earlier observation that aspects of the acute hepatocellular toxicity of dioxin are dependent upon IL1-like cytokine signaling. To address this issue, we employed a triple knock-out (TKO) mouse model with null alleles at the loci encoding the three relevant receptors for tumor necrosis factors α and β and IL-1α and IL-1β (i.e., null alleles at the Tnfrsf1a, Tnfrsf1b, and Il-1r1 loci). The observation that TKO mice were resistant to the tumor promoting effects of dioxin in liver suggests that inflammatory cytokines play an important step in dioxin mediated liver tumor promotion in the mouse. Collectively, these data support the idea that the mechanism of dioxin acute hepatotoxicity and its activity as a promoter in a mouse two stage liver cancer model may be similar, i.e., tumor promotion by dioxin, like acute hepatotoxicity, are mediated by the linked action of two receptor systems, the AHR and the receptors for the “IL-1-like” cytokines. PMID:24718703

  4. Thyroid hormone receptor binds to a site in the rat growth hormone promoter required for induction by thyroid hormone

    International Nuclear Information System (INIS)

    Koenig, R.J.; Brent, G.A.; Warne, R.L.; Larsen, P.R.; Moore, D.D.

    1987-01-01

    Transcription of the rat growth hormone (rGH) gene in pituitary cells is increased by addition of thyroid hormone (T3). This induction is dependent on the presence of specific sequences just upstream of the rGH promoter. The authors have partially purified T3 receptor from rat liver and examined its interaction with these rGH sequences. They show here that T3 receptor binds specifically to a site just upstream of the basal rGH promoter. This binding site includes two copies of a 7-base-pair direct repeat, the centers of which are separated by 10 base pairs. Deletions that specifically remove the T3 receptor binding site drastically reduce response to T3 in transient transfection experiments. These results demonstrate that T3 receptor can recognize specific DNA sequences and suggest that it can act directly as a positive transcriptional regulatory factor

  5. Specific Activation of the Alternative Cardiac Promoter ofCacna1cby the Mineralocorticoid Receptor.

    Science.gov (United States)

    Mesquita, Thassio R; Auguste, Gaelle; Falcón, Debora; Ruiz-Hurtado, Gema; Salazar-Enciso, Rogelio; Sabourin, Jessica; Lefebvre, Florence; Viengchareun, Say; Kobeissy, Hussein; Lechêne, Patrick; Nicolas, Valerie; Fernández-Celis, Amaya; Gomez, Susana; Lauton-Santos, Sandra; Morel, Eric; Rueda, Angelica; López-Andrés, Natalia; Gomez, Ana M; Lombes, Marc; Benitah, Jean-Pierre

    2018-02-21

    Rationale: The mineralocorticoid receptor (MR) antagonists belong to the current therapeutic armamentarium for the management of cardiovascular diseases, but the mechanisms conferring their beneficial effects are poorly understood. Part of the cardiovascular effects of MR are due to the regulation of L-type Ca v 1.2 Ca 2+ channel expression, which is generated by tissue-specific alternative promoters as a long 'cardiac' (Ca v 1.2-LNT) or a short 'vascular' (Ca v 1.2-SNT) N-terminal transcripts. Objective: To analyze the molecular mechanisms by which aldosterone, through MR, modulates Ca v 1.2 expression and function in a tissue-specific manner. Methods and Results: In primary cultures of neonatal rat ventricular myocytes, aldosterone exposure for 24 hours increased in a concentration-dependent manner Ca v 1.2-LNT expression at both mRNA and protein levels, correlating with enhanced concentration-, time- and MR-dependent P1-promoter activity. In silico analysis and mutagenesis identified MR interaction with both specific activating and repressing DNA binding elements on the P1-promoter. The relevance of this regulation is confirmed both ex and in vivo in transgenic mice harboring the luciferase reporter gene under the control of the 'cardiac' P1-promoter. Moreover, we show that this cis-regulatory mechanism is not limited to the heart. Indeed, in smooth muscle cells from different vascular beds, in which the Ca v 1.2-SNT is normally the major isoform, we found that MR signaling activates 'cardiac' Ca v 1.2-LNT expression through P1-promoter activation, leading to vascular contractile dysfunction. These results were further corroborated in hypertensive aldosterone-salt rodent models, showing notably a positive correlation between blood pressure and 'cardiac' P1-promoter activity in aorta. This new vascular Ca v 1.2-LNT molecular signature reduced sensitivity to the Ca 2+ channel blocker, nifedipine, in aldosterone-treated vessels. Conclusions: Our results reveal that

  6. The pentapeptide RM-131 promotes food intake and adiposity in wildtype mice but not in mice lacking the ghrelin receptor

    Directory of Open Access Journals (Sweden)

    Katrin eFischer

    2015-01-01

    Full Text Available The gastrointestinal peptide hormone ghrelin is the endogenous ligand of the growth hormone secretagogue receptor (GHSR, a.k.a. ghrelin receptor, GHR. Currently, ghrelin is the only circulating peripheral hormone with the ability to promote a positive energy balance by stimulating food intake while decreasing energy expenditure and body fat utilization, as defined in rodents. Based on these and additional, beneficial effects on metabolism, the endogenous ghrelin system is considered an attractive target to treat diverse pathological conditions including those associated with eating/wasting disorders and cachexia. As the pharmacological potential of ghrelin is hampered by its relatively short half-life, ghrelin analogs with enhanced pharmacokinetics offer the potential to sustainably improve metabolism. One of these ghrelin analogs is the pentapeptide RM-131, which promotes food intake and adiposity with higher potency as compared to native ghrelin in rodents. Whereas the effect of RM-131 on energy metabolism is solidly confirmed in rodents, it remains elusive whether RM-131 exerts its effect solely via the ghrelin receptor. Accordingly, we assessed the receptor specificity of RM-131 to promote food intake and adiposity in mice lacking the GHR. Our data show that in wildtype mice RM-131 potently promotes weight gain and adiposity through stimulation of food intake. However, RM-131 fails to affect food intake and body weight in mice lacking the GHR, underlining that the anabolic effects of RM-131 are mediated via the ghrelin receptor in mice.

  7. Involvement of promoter methylation in the regulation of Pregnane X receptor in colon cancer cells

    International Nuclear Information System (INIS)

    Habano, Wataru; Gamo, Toshie; Terashima, Jun; Sugai, Tamotsu; Otsuka, Koki; Wakabayashi, Go; Ozawa, Shogo

    2011-01-01

    Pregnane X receptor (PXR) is a key transcription factor that regulates drug metabolizing enzymes such as cytochrome P450 (CYP) 3A4, and plays important roles in intestinal first-pass metabolism. Although there is a large inter-individual heterogeneity with intestinal CYP3A4 expression and activity, the mechanism driving these differences is not sufficiently explained by genetic variability of PXR or CYP3A4. We examined whether epigenetic mechanisms are involved in the regulation of PXR/CYP3A4 pathways in colon cancer cells. mRNA levels of PXR, CYP3A4 and vitamin D receptor (VDR) were evaluated by quantitative real-time PCR on 6 colon cancer cell lines (Caco-2, HT29, HCT116, SW48, LS180, and LoVo). DNA methylation status was also examined by bisulfite sequencing of the 6 cell lines and 18 colorectal cancer tissue samples. DNA methylation was reversed by the treatment of these cell lines with 5-aza-2'-deoxycytidine (5-aza-dC). The 6 colon cancer cell lines were classified into two groups (high or low expression cells) based on the basal level of PXR/CYP3A4 mRNA. DNA methylation of the CpG-rich sequence of the PXR promoter was more densely detected in the low expression cells (Caco-2, HT29, HCT116, and SW48) than in the high expression cells (LS180 and LoVo). This methylation was reversed by treatment with 5-aza-dC, in association with re-expression of PXR and CYP3A4 mRNA, but not VDR mRNA. Therefore, PXR transcription was silenced by promoter methylation in the low expression cells, which most likely led to downregulation of CYP3A4 transactivation. Moreover, a lower level of PXR promoter methylation was observed in colorectal cancer tissues compared with adjacent normal mucosa, suggesting upregulation of the PXR/CYP3A4 mRNAs during carcinogenesis. PXR promoter methylation is involved in the regulation of intestinal PXR and CYP3A4 mRNA expression and might be associated with the inter-individual variability of the drug responses of colon cancer cells

  8. L-type Ca2+ channel blockers promote Ca2+ accumulation when dopamine receptors are activated in striatal neurons.

    Science.gov (United States)

    Eaton, Molly E; Macías, Wendy; Youngs, Rachael M; Rajadhyaksha, Anjali; Dudman, Joshua T; Konradi, Christine

    2004-11-24

    Dopamine (DA) receptor-mediated signal transduction and gene expression play a central role in many brain disorders from schizophrenia to Parkinson's disease to addiction. While trying to evaluate the role of L-type Ca2+ channels in dopamine D1 receptor-mediated phosphorylation of the transcription factor cyclic AMP response element-binding protein (CREB), we found that activation of dopamine D1 receptors alters the properties of L-type Ca2+ channel inhibitors and turns them into facilitators of Ca2+ influx. In D1 receptor-stimulated neurons, L-type Ca2+ channel blockers promote cytosolic Ca2+ accumulation. This leads to the activation of a molecular signal transduction pathway and CREB phosphorylation. In the absence of dopamine receptor stimulation, L-type Ca2+ channel blockers inhibit CREB phosphorylation. The effect of dopamine on L-type Ca2+ channel blockers is dependent on protein kinase A (PKA), suggesting that protein phosphorylation plays a role in this phenomenon. Because of the adverse effect of activated dopamine receptors on L-type Ca2+ channel blocker action, the role of L-type Ca2+ channels in the dopamine D1 receptor signal transduction pathway cannot be assessed with pharmacological tools. However, with antisense technology, we demonstrate that L-type Ca2+ channels contribute to D1 receptor-mediated CREB phosphorylation. We conclude that the D1 receptor signal transduction pathway depends on L-type Ca2+ channels to mediate CREB phosphorylation.

  9. Aryl hydrocarbon receptor downregulates MYCN expression and promotes cell differentiation of neuroblastoma.

    Directory of Open Access Journals (Sweden)

    Pei-Yi Wu

    Full Text Available Neuroblastoma (NB is the most common malignant disease of infancy. MYCN amplification is a prognostic factor for NB and is a sign of highly malignant disease and poor patient prognosis. In this study, we aimed to investigate novel MYCN-related genes and assess how they affect NB cell behavior. The different gene expression found in 10 MYCN amplification NB tumors and 10 tumors with normal MYCN copy number were analyzed using tissue oligonucleotide microarrays. Ingenuity Pathway Analysis was subsequently performed to identify the potential genes involved in MYCN regulation pathways. Aryl hydrocarbon receptor (AHR, a receptor for dioxin-like compounds, was found to be inversely correlated with MYCN expression in NB tissues. This correlation was confirmed in a further 14 human NB samples. Moreover, AHR expression in NB tumors was found to correlate highly with histological grade of differentiation. In vitro studies revealed that AHR overexpression in NB cells induced spontaneous cell differentiation. In addition, it was found that ectopic expression of AHR suppressed MYCN promoter activity resulting in downregulation of MYCN expression. The suppression effect of AHR on the transcription of MYCN was compensated for by E2F1 overexpression, indicating that E2F1 is involved in the AHR-regulating MYCN pathway. Furthermore, AHR shRNA promotes the expression of E2F1 and MYCN in NB cells. These findings suggest that AHR is one of the upstream regulators of MYCN. Through the modulation of E2F1, AHR regulates MYCN gene expression, which may in turn affect NB differentiation.

  10. TRAIL/DR5 signaling promotes macrophage foam cell formation by modulating scavenger receptor expression.

    Directory of Open Access Journals (Sweden)

    Fang Fang Liu

    Full Text Available Tumor necrosis factor-related apoptosis-inducing ligand (TRAIL/Apo2L has been shown to have protective effects against atherosclerosis. However, whether TRAIL has any effects on expression of macrophage scavenger receptors and lipid uptake has not yet been studied. Macrophage lines RAW264.7 and THP-1, and mouse primary peritoneal macrophages, were cultured in vitro and treated with recombinant human TRAIL. Real-time PCR and western blot were performed to measure mRNA and protein expressions. Foam cell formation was assessed by internalization of acetylated and oxidized low-density lipoproteins (LDL. Apoptosis was measured by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling. We found that TRAIL treatment increased expression of scavenger receptor (SR-AI and SR-BI in a time- and dose-dependent manner, and this effect was accompanied by increased foam cell formation. These effects of TRAIL were abolished by a TRAIL neutralizing antibody or in DR5 receptor-deficient macrophages. The increased LDL uptake by TRAIL was blocked by SR-AI gene silencing or the SR-AI inhibitor poly(I:C, while SR-BI blockade with BLT-1 had no effect. TRAIL-induced SR-AI expression was blocked by the inhibitor of p38 mitogen-activated protein kinase, but not by inhibitors of ERK1/2 or JNK. TRAIL also induced apoptosis in macrophages. In contrast to macrophages, TRAIL showed little effects on SR expression or apoptosis in vascular smooth muscle cells. In conclusion, our results demonstrate that TRAIL promotes macrophage lipid uptake via SR-AI upregulation through activation of the p38 pathway.

  11. SPARC and GluA1-Containing AMPA Receptors Promote Neuronal Health Following CNS Injury

    Directory of Open Access Journals (Sweden)

    Emma V. Jones

    2018-02-01

    Full Text Available The proper formation and maintenance of functional synapses in the central nervous system (CNS requires communication between neurons and astrocytes and the ability of astrocytes to release neuromodulatory molecules. Previously, we described a novel role for the astrocyte-secreted matricellular protein SPARC (Secreted Protein, Acidic and Rich in Cysteine in regulating α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptors (AMPARs and plasticity at developing synapses. SPARC is highly expressed by astrocytes and microglia during CNS development but its level is reduced in adulthood. Interestingly, SPARC has been shown to be upregulated in CNS injury and disease. However, the role of SPARC upregulation in these contexts is not fully understood. In this study, we investigated the effect of chronic SPARC administration on glutamate receptors on mature hippocampal neuron cultures and following CNS injury. We found that SPARC treatment increased the number of GluA1-containing AMPARs at synapses and enhanced synaptic function. Furthermore, we determined that the increase in synaptic strength induced by SPARC could be inhibited by Philanthotoxin-433, a blocker of homomeric GluA1-containing AMPARs. We then investigated the effect of SPARC treatment on neuronal health in an injury context where SPARC expression is upregulated. We found that SPARC levels are increased in astrocytes and microglia following middle cerebral artery occlusion (MCAO in vivo and oxygen-glucose deprivation (OGD in vitro. Remarkably, chronic pre-treatment with SPARC prevented OGD-induced loss of synaptic GluA1. Furthermore, SPARC treatment reduced neuronal death through Philanthotoxin-433 sensitive GluA1 receptors. Taken together, this study suggests a novel role for SPARC and GluA1 in promoting neuronal health and recovery following CNS damage.

  12. Ritonavir binds to and downregulates estrogen receptors: Molecular mechanism of promoting early atherosclerosis

    Energy Technology Data Exchange (ETDEWEB)

    Xiang, Jin [Ministry of Education Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Science, Wuhan University, Wuhan 430071 (China); Wang, Ying [Department of Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Su, Ke [Department of Nephrology, Renmin Hospital of Wuhan University, Wuhan 430060 (China); Liu, Min [Ministry of Education Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Science, Wuhan University, Wuhan 430071 (China); Hu, Peng-Chao [Department of Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Ma, Tian; Li, Jia-Xi [Ministry of Education Laboratory of Combinatorial Biosynthesis and Drug Discovery, School of Pharmaceutical Science, Wuhan University, Wuhan 430071 (China); Wei, Lei [Department of Pathophysiology, School of Medicine, Wuhan University, Wuhan 430071 (China); Zheng, Zhongliang, E-mail: biochem@whu.edu.cn [State Key Laboratory of Virology, College of Life Sciences, Wuhan University, Wuhan 430072 (China); Yang, Fang, E-mail: fang-yang@whu.edu.cn [Department of Physiology, School of Medicine, Wuhan University, Wuhan 430071 (China)

    2014-10-01

    Estrogenic actions are closely related to cardiovascular disease. Ritonavir (RTV), a human immunodeficiency virus (HIV) protease inhibitor, induces atherosclerosis in an estrogen-related manner. However, how RTV induce pathological phenotypes through estrogen pathway remains unclear. In this study, we found that RTV increases thickness of coronary artery walls of Sprague Dawley rats and plasma free fatty acids (FFA) levels. In addition, RTV could induce foam cell formation, downregulate both estrogen receptor α (ERα) and ERβ expression, upregulate G protein-coupled estrogen receptor (GPER) expression, and all of them could be partially blocked by 17β-estradiol (E2), suggesting RTV acts as an antagonist for E2. Computational modeling shows a similar interaction with ERα between RTV and 2-aryl indoles, which are highly subtype-selective ligands for ERα. We also found that RTV directly bound to ERα and selectively inhibited the nuclear localization of ERα, and residue Leu536 in the hydrophobic core of ligand binding domain (LBD) was essential for the interaction with RTV. In addition, RTV did not change the secondary structure of ERα-LBD like E2, which explained how ERα lost the capacity of nuclear translocation under the treatment of RTV. All of the evidences suggest that ritonavir acts as an antagonist for 17β-estradiol in regulating α subtype estrogen receptor function and early events of atherosclerosis. - Graphical abstract: RTV directly binds to ERα and Leu536 in the hydrophobic core of ligand binding domain is essential for the interaction. - Highlights: • RTV increases the thickness of rat coronary artery wall and foam cell formation. • RTV downregulates the expression of ERα and ERβ. • RTV inhibits ERα promoter activity. • RTV directly binds to ERα and the key amino acid is Leu536. • RTV inhibits the nuclear translocation of ERα and GPER.

  13. Histamine-HisCl1 Receptor Axis Regulates Wake-Promoting Signals in Drosophila melanogaster

    Science.gov (United States)

    Oh, Yangkyun; Jang, Donghoon; Sonn, Jun Young; Choe, Joonho

    2013-01-01

    Histamine and its two receptors, histamine-gated chloride channel subunit 1 (HisCl1) and ora transientless (Ort), are known to control photoreception and temperature sensing in Drosophila. However, histamine signaling in the context of neural circuitry for sleep-wake behaviors has not yet been examined in detail. Here, we obtained mutant flies with compromised or enhanced histamine signaling and tested their baseline sleep. Hypomorphic mutations in histidine decarboxylase (HDC), an enzyme catalyzing the conversion from histidine to histamine, caused an increase in sleep duration. Interestingly, hisCl1 mutants but not ort mutants showed long-sleep phenotypes similar to those in hdc mutants. Increased sleep duration in hisCl1 mutants was rescued by overexpressing hisCl1 in circadian pacemaker neurons expressing a neuropeptide pigment dispersing factor (PDF). Consistently, RNA interference (RNAi)-mediated depletion of hisCl1 in PDF neurons was sufficient to mimic hisCl1 mutant phenotypes, suggesting that PDF neurons are crucial for sleep regulation by the histamine-HisCl1 signaling. Finally, either hisCl1 mutation or genetic ablation of PDF neurons dampened wake-promoting effects of elevated histamine signaling via direct histamine administration. Taken together, these data clearly demonstrate that the histamine-HisCl1 receptor axis can activate and maintain the wake state in Drosophila and that wake-activating signals may travel via the PDF neurons. PMID:23844178

  14. Estrogen and estrogen receptor alpha promotes malignancy and osteoblastic tumorigenesis in prostate cancer.

    Science.gov (United States)

    Mishra, Sweta; Tai, Qin; Gu, Xiang; Schmitz, James; Poullard, Ashley; Fajardo, Roberto J; Mahalingam, Devalingam; Chen, Xiaodong; Zhu, Xueqiong; Sun, Lu-Zhe

    2015-12-29

    The role of estrogen signaling in regulating prostate tumorigenesis is relatively underexplored. Although, an increasing body of evidence has linked estrogen receptor beta (ERß) to prostate cancer, the function of estrogen receptor alpha (ERα) in prostate cancer is not very well studied. We have discovered a novel role of ERα in the pathogenesis of prostate tumors. Here, we show that prostate cancer cells express ERα and estrogen induces oncogenic properties in prostate cancer cells through ERα. Importantly, ERα knockdown in the human prostate cancer PacMetUT1 cells as well as pharmacological inhibition of ERα with ICI 182,780 inhibited osteoblastic lesion formation and lung metastasis in vivo. Co-culture of pre-osteoblasts with cancer cells showed a significant induction of osteogenic markers in the pre-osteoblasts, which was attenuated by knockdown of ERα in cancer cells suggesting that estrogen/ERα signaling promotes crosstalk between cancer and osteoblastic progenitors to stimulate osteoblastic tumorigenesis. These results suggest that ERα expression in prostate cancer cells is essential for osteoblastic lesion formation and lung metastasis. Thus, inhibition of ERα signaling in prostate cancer cells may be a novel therapeutic strategy to inhibit the osteoblastic lesion development as well as lung metastasis in patients with advanced prostate cancer.

  15. Variants in the dopamine-4-receptor gene promoter are not associated with sensation seeking in skiers.

    Science.gov (United States)

    Thomson, Cynthia J; Rajala, Amelia K; Carlson, Scott R; Rupert, Jim L

    2014-01-01

    Sensation seeking is a personality trait that has been associated with disinhibited behaviours including substance use and gambling, but also with high-risk sport practices including skydiving, paragliding, and downhill skiing. Twin studies have shown that sensation seeking is moderately heritable, and candidate genes encoding components involved in dopaminergic transmission have been investigated as contributing to this type of behaviour. To determine whether variants in the regulatory regions of the dopamine-4-receptor gene (DRD4) influenced sport-specific sensation seeking, we analyzed five polymorphisms (-1106T/C, -906T/C, -809G/A, -291C/T, 120-bp duplication) in the promoter region of the gene in a cohort of skiers and snowboarders (n = 599) that represented a broad range of sensation seeking behaviours. We grouped subjects by genotype at each of the five loci and compared impulsive sensation seeking and domain-specific (skiing) sensation seeking between groups. There were no significant associations between genotype(s) and general or domain-specific sensation seeking in the skiers and snowboarders, suggesting that while DRD4 has previously been implicated in sensation seeking, the promoter variants investigated in this study do not contribute to sensation seeking in this athlete population.

  16. Identification of a novel human glucagon receptor promoter: regulation by cAMP and PGC-1alpha

    DEFF Research Database (Denmark)

    Mortensen, Ole Hartvig; Dichmann, Darwin Sorento; Abrahamsen, Niels

    2007-01-01

    the promoter regions of the human glucagon receptor gene. Primer extension studies yielded multiple products in both liver and pancreas, corresponding to transcription start sites situated at -166 and -477 relative to the start of translation, indicating two putative promoters. Both transcription start sites...... between 1051 and 1016 base pairs upstream of the transcription start site, which contains several putative cAMP responsive elements. Expression of peroxisome proliferator-activated receptor gamma coactivator 1alpha (PGC-1alpha), known to be upregulated in the liver by fasting, was found to abolish the c......AMP-dependent downregulation of glucagon receptor mRNA expression in vitro, whereas overexpression of PGC-1beta had no effect....

  17. Epidermal Growth Factor Receptor activation promotes ADA3 acetylation through the AKT-p300 pathway.

    Science.gov (United States)

    Srivastava, Shashank; Mohibi, Shakur; Mirza, Sameer; Band, Hamid; Band, Vimla

    2017-08-18

    The ADA3 (Alteration/Deficiency in Activation 3) protein is an essential adaptor component of several Lysine Acetyltransferase (KAT) complexes involved in chromatin modifications. Previously, we and others have demonstrated a crucial role of ADA3 in cell cycle progression and in maintenance of genomic stability. Recently, we have shown that acetylation of ADA3 is key to its role in cell cycle progression. Here, we demonstrate that AKT activation downstream of Epidermal Growth Factor Receptor (EGFR) family proteins stimulation leads to phosphorylation of p300, which in turn promotes the acetylation of ADA3. Inhibition of upstream receptor tyrosine kinases (RTKs), HER1 (EGFR)/HER2 by lapatinib and the accompanying reduction of phospho-AKT levels led to a decrease in p300 phosphorylation and ADA3 protein levels. The p300/PCAF inhibitor garcinol also destabilized the ADA3 protein in a proteasome-dependent manner and an ADA3 mutant with K→R mutations exhibited a marked increase in half-life, consistent with opposite role of acetylation and ubiquitination of ADA3 on shared lysine residues. ADA3 knockdown led to cell cycle inhibitory effects, as well as apoptosis similar to those induced by lapatinib treatment of HER2+ breast cancer cells, as seen by accumulation of CDK inhibitor p27, reduction in mitotic marker pH3(S10), and a decrease in the S-phase marker PCNA, as well as the appearance of cleaved PARP. Taken together our results reveal a novel RTK-AKT-p300-ADA3 signaling pathway involved in growth factor-induced cell cycle progression.

  18. Insight into the molecular mechanisms of glucocorticoid receptor action promotes identification of novel ligands with an improved therapeutic index.

    Science.gov (United States)

    Schäcke, Heike; Rehwinkel, Hartmut; Asadullah, Khusru; Cato, Andrew C B

    2006-08-01

    Glucocorticoids are highly effective in the therapy of inflammatory and autoimmune disorders. Their beneficial action is restricted because of their adverse effects upon prolonged usage. Topical glucocorticoids that act locally have been developed to significantly reduce systemic side effects. Nonetheless, undesirable cutaneous effects such as skin atrophy persist from the use of topical glucocorticoids. There is therefore a high medical need for drugs as effective as glucocorticoids but with a reduced side-effect profile. Glucocorticoids function by binding to and activating the glucocorticoid receptor that positively or negatively regulates the expression of specific genes. Several experiments suggest that the negative regulation of gene expression by the glucocorticoid receptor accounts for its anti-inflammatory action. This occurs through direct or indirect binding of the receptor to transcription factors such as activator protein-1, nuclear factor-kappaB or interferon regulatory factor-3 that are already bound to their regulatory sites. The positive action of the receptor occurs through homodimer binding of the receptor to discrete nucleotide sequences and this possibly contributes to some of the adverse effects of the hormone. Glucocorticoid receptor ligands that promote the negative regulatory action of the receptor with reduced positive regulatory function should therefore show improved therapeutic potential. A complete separation of the positive from the negative regulatory activities of the receptor has so far not been possible because of the interdependent nature of the two regulatory processes. Nevertheless, considerable improvement in the therapeutic action of glucocorticoid receptor ligands is being achieved through the use of key molecular targets for screening novel glucocorticoid receptor ligands.

  19. Supersensitive Kappa Opioid Receptors Promotes Ethanol Withdrawal-Related Behaviors and Reduce Dopamine Signaling in the Nucleus Accumbens.

    Science.gov (United States)

    Rose, Jamie H; Karkhanis, Anushree N; Chen, Rong; Gioia, Dominic; Lopez, Marcelo F; Becker, Howard C; McCool, Brian A; Jones, Sara R

    2016-05-01

    Chronic ethanol exposure reduces dopamine transmission in the nucleus accumbens, which may contribute to the negative affective symptoms associated with ethanol withdrawal. Kappa opioid receptors have been implicated in withdrawal-induced excessive drinking and anxiety-like behaviors and are known to inhibit dopamine release in the nucleus accumbens. The effects of chronic ethanol exposure on kappa opioid receptor-mediated changes in dopamine transmission at the level of the dopamine terminal and withdrawal-related behaviors were examined. Five weeks of chronic intermittent ethanol exposure in male C57BL/6 mice were used to examine the role of kappa opioid receptors in chronic ethanol-induced increases in ethanol intake and marble burying, a measure of anxiety/compulsive-like behavior. Drinking and marble burying were evaluated before and after chronic intermittent ethanol exposure, with and without kappa opioid receptor blockade by nor-binaltorphimine (10mg/kg i.p.). Functional alterations in kappa opioid receptors were assessed using fast scan cyclic voltammetry in brain slices containing the nucleus accumbens. Chronic intermittent ethanol-exposed mice showed increased ethanol drinking and marble burying compared with controls, which was attenuated with kappa opioid receptor blockade. Chronic intermittent ethanol-induced increases in behavior were replicated with kappa opioid receptor activation in naïve mice. Fast scan cyclic voltammetry revealed that chronic intermittent ethanol reduced accumbal dopamine release and increased uptake rates, promoting a hypodopaminergic state of this region. Kappa opioid receptor activation with U50,488H concentration-dependently decreased dopamine release in both groups; however, this effect was greater in chronic intermittent ethanol-treated mice, indicating kappa opioid receptor supersensitivity in this group. These data suggest that the chronic intermittent ethanol-induced increase in ethanol intake and anxiety

  20. 5-HT2A receptor-mediated excitation on cerebellar fastigial nucleus neurons and promotion of motor behaviors in rats.

    Science.gov (United States)

    Zhang, Chang-Zheng; Zhuang, Qian-Xing; He, Ye-Cheng; Li, Guang-Ying; Zhu, Jing-Ning; Wang, Jian-Jun

    2014-07-01

    It has long been known that serotonergic afferent inputs are the third largest afferent population in the cerebellum after mossy fibers and climbing fibers. However, the role of serotonergic inputs in cerebellar-mediated motor behaviors is still largely unknown. Here, we show that only 5-HT2A receptors among the 5-HT2 receptor subfamily are expressed and localized in the rat cerebellar fastigial nucleus (FN), one of the ultimate outputs of the spinocerebellum precisely regulating trunk and limb movements. Remarkably, selective activation of 5-HT2A receptors evokes a postsynaptic excitatory effect on FN neurons in a concentration-dependent manner in vitro, which is in accord with the 5-HT-elicited excitation on the same tested neurons. Furthermore, selective 5-HT2A receptor antagonist M100907 concentration-dependently blocks the excitatory effects of 5-HT and TCB-2, a 5-HT2A receptor agonist, on FN neurons. Consequently, microinjection of 5-HT into bilateral FNs significantly promotes rat motor performances on accelerating rota-rod and balance beam and narrows stride width rather than stride length in locomotion gait. All these motor behavioral effects are highly consistent with those of selective activation of 5-HT2A receptors in FNs, and blockage of the component of 5-HT2A receptor-mediated endogenous serotonergic inputs in FNs markedly attenuates these motor performances. All these results demonstrate that postsynaptic 5-HT2A receptors greatly contribute to the 5-HT-mediated excitatory effect on cerebellar FN neurons and promotion of the FN-related motor behaviors, suggesting that serotonergic afferent inputs may actively participate in cerebellar motor control through their direct modulation on the final output of the spinocerebellum.

  1. Estrogen regulates transcription of the ovine oxytocin receptor gene through GC-rich SP1 promoter elements.

    Science.gov (United States)

    Fleming, Joann G W; Spencer, Thomas E; Safe, Stephen H; Bazer, Fuller W

    2006-02-01

    Establishment of pregnancy in ruminants results from paracrine signaling by interferon tau (IFNT) from the conceptus to uterine endometrial luminal epithelia (LE) that prevents release of luteolytic prostaglandin F(2alpha) pulses. In cyclic and pregnant ewes, progesterone down-regulates progesterone receptor (PGR) gene expression in LE. In cyclic ewes, loss of PGR allows for increases in estrogen receptor alpha (ESR1) and then oxytocin receptor (OXTR) gene expression followed by oxytocin-induced prostaglandin F(2alpha) pulses. In pregnant ewes, IFNT inhibits transcription of the ESR1 gene, which presumably inhibits OXTR gene transcription. Alternatively, IFNT may directly inhibit OXTR gene transcription. The 5' promoter/enhancer region of the ovine OXTR gene was cloned and found to contain predicted binding sites for activator protein 1, SP1, and PGR, but not for ESR1. Deletion analysis showed that the basal promoter activity was dependent on the region from -144 to -4 bp that contained only SP1 sites. IFNT did not affect activity of the OXTR promoter. In cells transfected with ESR1, E2, and ICI 182,780 increased promoter activity due to GC-rich SP1 binding sites at positions -104 and -64. Mutation analyses showed that the proximal SP1 sites mediated ESR1 action as well as basal activity of the promoter. In response to progesterone, progesterone receptor B also increased OXTR promoter activity. SP1 protein was constitutively expressed and abundant in the LE of the ovine uterus. These results support the hypothesis that the antiluteolytic effects of IFNT are mediated by direct inhibition or silencing of ESR1 gene transcription, thereby precluding ESR1/SP1 from stimulating OXTR gene transcription.

  2. Promoter methylation of glucocorticoid receptor gene is associated with subclinical atherosclerosis: A monozygotic twin study.

    Science.gov (United States)

    Zhao, Jinying; An, Qiang; Goldberg, Jack; Quyyumi, Arshed A; Vaccarino, Viola

    2015-09-01

    Endothelial dysfunction assessed by brachial artery flow-mediated dilation (FMD) is a marker of early atherosclerosis. Glucocorticoid receptor gene (NR3C1) regulates many biological processes, including stress response, behavioral, cardiometabolic and immunologic functions. Genetic variants in NR3C1 have been associated with atherosclerosis and related risk factors. This study investigated the association of NR3C1 promoter methylation with FMD, independent of genetic and family-level environmental factors. We studied 84 middle-aged, male-male monozygotic twin pairs recruited from the Vietnam Era Twin Registry. Brachial artery FMD was measured by ultrasound. DNA methylation levels at 22 CpG residues in the NR3C1 exon 1F promoter region were quantified by bisulfite pyrosequencing in genomic DNA isolated from peripheral blood leukocytes. Co-twin control analyses were conducted to examine the association of methylation variation with FMD, adjusting for smoking, physical activity, body mass index, lipids, blood pressure, fasting glucose, and depressive symptoms. Multiple testing was corrected using the false discovery rate. Mean methylation level across the 22 studied CpG sites was 2.02%. Methylation alterations at 12 out of the 22 CpG residues were significantly associated with FMD. On average, a 1% increase in the intra-pair difference in mean DNA methylation was associated with 2.83% increase in the intra-pair difference in FMD (95% CI: 1.46-4.20; P atherosclerosis, independent of genetic, early family environmental and other risk factors. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  3. Pregnane X receptor activation and silencing promote steatosis of human hepatic cells by distinct lipogenic mechanisms.

    Science.gov (United States)

    Bitter, Andreas; Rümmele, Petra; Klein, Kathrin; Kandel, Benjamin A; Rieger, Jessica K; Nüssler, Andreas K; Zanger, Ulrich M; Trauner, Michael; Schwab, Matthias; Burk, Oliver

    2015-11-01

    In addition to its well-characterized role in the regulation of drug metabolism and transport by xenobiotics, pregnane X receptor (PXR) critically impacts on lipid homeostasis. In mice, both ligand-dependent activation and knockout of PXR were previously shown to promote hepatic steatosis. To elucidate the respective pathways in human liver, we generated clones of human hepatoma HepG2 cells exhibiting different PXR protein levels, and analyzed effects of PXR activation and knockdown on steatosis and expression of lipogenic genes. Ligand-dependent activation as well as knockdown of PXR resulted in increased steatosis in HepG2 cells. Activation of PXR induced the sterol regulatory element-binding protein (SREBP) 1-dependent lipogenic pathway via PXR-dependent induction of SREBP1a, which was confirmed in primary human hepatocytes. Inhibiting SREBP1 activity by blocking the cleavage-dependent maturation of SREBP1 protein impaired the induction of lipogenic SREBP1 target genes and triglyceride accumulation by PXR activation. On the other hand, PXR knockdown resulted in up-regulation of aldo-keto reductase (AKR) 1B10, which enhanced the acetyl-CoA carboxylase (ACC)-catalyzed reaction step of de novo lipogenesis. In a cohort of human liver samples histologically classified for non-alcoholic fatty liver disease, AKR1B10, SREBP1a and SREBP1 lipogenic target genes proved to be up-regulated in steatohepatitis, while PXR protein was reduced. In summary, our data suggest that activation and knockdown of PXR in human hepatic cells promote de novo lipogenesis and steatosis by induction of the SREBP1 pathway and AKR1B10-mediated increase of ACC activity, respectively, thus providing mechanistic explanations for a putative dual role of PXR in the pathogenesis of steatohepatitis.

  4. Sox2 is an androgen receptor-repressed gene that promotes castration-resistant prostate cancer.

    Directory of Open Access Journals (Sweden)

    Steven Kregel

    Full Text Available Despite advances in detection and therapy, castration-resistant prostate cancer continues to be a major clinical problem. The aberrant activity of stem cell pathways, and their regulation by the Androgen Receptor (AR, has the potential to provide insight into novel mechanisms and pathways to prevent and treat advanced, castrate-resistant prostate cancers. To this end, we investigated the role of the embryonic stem cell regulator Sox2 [SRY (sex determining region Y-box 2] in normal and malignant prostate epithelial cells. In the normal prostate, Sox2 is expressed in a portion of basal epithelial cells. Prostate tumors were either Sox2-positive or Sox2-negative, with the percentage of Sox2-positive tumors increasing with Gleason Score and metastases. In the castration-resistant prostate cancer cell line CWR-R1, endogenous expression of Sox2 was repressed by AR signaling, and AR chromatin-IP shows that AR binds the enhancer element within the Sox2 promoter. Likewise, in normal prostate epithelial cells and human embryonic stem cells, increased AR signaling also decreases Sox2 expression. Resistance to the anti-androgen MDV3100 results in a marked increase in Sox2 expression within three prostate cancer cell lines, and in the castration-sensitive LAPC-4 prostate cancer cell line ectopic expression of Sox2 was sufficient to promote castration-resistant tumor formation. Loss of Sox2 expression in the castration-resistant CWR-R1 prostate cancer cell line inhibited cell growth. Up-regulation of Sox2 was not associated with increased CD133 expression but was associated with increased FGF5 (Fibroblast Growth Factor 5 expression. These data propose a model of elevated Sox2 expression due to loss of AR-mediated repression during castration, and consequent castration-resistance via mechanisms not involving induction of canonical embryonic stem cell pathways.

  5. CISH promoter polymorphism effects on T cell cytokine receptor signaling and type 1 diabetes susceptibility.

    Science.gov (United States)

    Seyfarth, Julia; Ahlert, Heinz; Rosenbauer, Joachim; Baechle, Christina; Roden, Michael; Holl, Reinhard W; Mayatepek, Ertan; Meissner, Thomas; Jacobsen, Marc

    2018-02-06

    Impaired regulatory T cell immunity plays a central role in the development of type 1 diabetes (T1D). Interleukin-2 receptor (IL-2R) signaling is essential for regulatory T cells (T REG ), and cytokine-inducible SH2-containing protein (CIS) regulates IL-2R signaling as a feedback inhibitor. Previous studies identified association of CISH promoter region single nucleotide polymorphisms (SNPs) with susceptibility to infectious diseases. Here we analyzed allele frequencies of three CISH SNPs (i.e., rs809451, rs414171, rs2239751) in a study of T1D patients (n = 260, onset age  10 years). Minor allele frequencies were compared to a control cohort of the 1000 Genomes Project. Assigned haplotypes were determined for effects on T1D manifestation and severity. Finally, the CISH haplotype influence on cytokine signaling and function was explored in T cells from healthy donors. We detected similar minor allele frequencies between T1D patients and the control cohort. T1D onset age, residual serum C-peptide level, and insulin requirement were comparable between different haplotypes. Only minor differences between the haplotypes were found for in vitro cytokine (i.e., IL-2, IL-7)-induced CIS mRNA expression. STAT5 phosphorylation was induced by IL-2 or IL-7, but no differences were found between the haplotypes. T REG purified from healthy donors with the two most common haplotypes showed similar capacity to inhibit heterologous effector T cells. This study provides no evidence for an association of CISH promoter SNPs with susceptibility to T1D or severity of disease. In contrast to previous studies, no influence of different haplotypes on CIS mRNA expression or T cell-mediated functions was found.

  6. Thromboxane A(2 receptor stimulation promotes closure of the rat ductus arteriosus through enhancing neointima formation.

    Directory of Open Access Journals (Sweden)

    Tomohiro Yokota

    Full Text Available Ductus arteriosus (DA closure follows constriction and remodeling of the entire vessel wall. Patent ductus arteriosus occurs when the DA does not close after birth, and this condition is currently treated using cyclooxygenase inhibitors. However, the efficacy of cyclooxygenase inhibitors is often limited. Our previous study demonstrated that low-dose thromboxane A2 receptor (TP stimulation constricted the DA with minimal adverse effects in rat neonates. However, its effect on DA remodeling remains unknown. In this study, we focused on the impact of the exogenous TP stimulation on the DA remodeling, especially intimal thickening. Using DA explants from rat fetuses at embryonic day 19 as a ex vivo model and primary cultured rat DA smooth muscle cells from embryonic day 21 as a in vitro model, we evaluated the effect of TP stimulation on the DA remodeling. The selective TP agonists U46619 and I-BOP promoted neointima formation in the ex vivo DA explants, and TP stimulation increased DA SMC migration in a dose-dependent manner. Both effects were inhibited by the selective TP antagonist SQ29548 or the siRNA against TP. TP stimulation also increased DA SMC proliferation in the presence of 10% fetal bovine serum. LC/MS/MS analysis revealed that TP stimulation increased secretion of several extracellular matrix proteins that may contribute to an increase in neointima formation. In conclusion, we uncovered that exogenous administration of TP agonist promotes neointima formation through the induction of migration and proliferation of DA SMC, which could contribute to DA closure and also to its vasoconstrictive action.

  7. Zebrafish GDNF and its co-receptor GFRα1 activate the human RET receptor and promote the survival of dopaminergic neurons in vitro.

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    Tuulia Saarenpää

    Full Text Available Glial cell line-derived neurotrophic factor (GDNF is a ligand that activates, through co-receptor GDNF family receptor alpha-1 (GFRα1 and receptor tyrosine kinase "RET", several signaling pathways crucial in the development and sustainment of multiple neuronal populations. We decided to study whether non-mammalian orthologs of these three proteins have conserved their function: can they activate the human counterparts? Using the baculovirus expression system, we expressed and purified Danio rerio RET, and its binding partners GFRα1 and GDNF, and Drosophila melanogaster RET and two isoforms of co-receptor GDNF receptor-like. Our results report high-level insect cell expression of post-translationally modified and dimerized zebrafish RET and its binding partners. We also found that zebrafish GFRα1 and GDNF are comparably active as mammalian cell-produced ones. We also report the first measurements of the affinity of the complex to RET in solution: at least for zebrafish, the Kd for GFRα1-GDNF binding RET is 5.9 μM. Surprisingly, we also found that zebrafish GDNF as well as zebrafish GFRα1 robustly activated human RET signaling and promoted the survival of cultured mouse dopaminergic neurons with comparable efficiency to mammalian GDNF, unlike E. coli-produced human proteins. These results contradict previous studies suggesting that mammalian GFRα1 and GDNF cannot bind and activate non-mammalian RET and vice versa.

  8. Activated scavenger receptor A promotes glial internalization of aβ.

    Science.gov (United States)

    Zhang, He; Su, Ya-jing; Zhou, Wei-wei; Wang, Shao-wei; Xu, Peng-xin; Yu, Xiao-lin; Liu, Rui-tian

    2014-01-01

    Beta-amyloid (Aβ) aggregates have a pivotal role in pathological processing of Alzheimer's disease (AD). The clearance of Aβ monomer or aggregates is a causal strategy for AD treatment. Microglia and astrocytes are the main macrophages that exert critical neuroprotective roles in the brain. They may effectively clear the toxic accumulation of Aβ at the initial stage of AD, however, their functions are attenuated because of glial overactivation. In this study, we first showed that heptapeptide XD4 activates the class A scavenger receptor (SR-A) on the glia by increasing the binding of Aβ to SR-A, thereby promoting glial phagocytosis of Aβ oligomer in microglia and astrocytes and triggering intracellular mitogen-activated protein kinase (MAPK) signaling cascades. Moreover, XD4 enhances the internalization of Aβ monomers to microglia and astrocytes through macropinocytosis or SR-A-mediated phagocytosis. Furthermore, XD4 significantly inhibits Aβ oligomer-induced cytotoxicity to glial cells and decreases the production of proinflammatory cytokines, such as TNF-α and IL-1β, in vitro and in vivo. Our findings may provide a novel strategy for AD treatment by activating SR-A.

  9. Activated scavenger receptor A promotes glial internalization of aβ.

    Directory of Open Access Journals (Sweden)

    He Zhang

    Full Text Available Beta-amyloid (Aβ aggregates have a pivotal role in pathological processing of Alzheimer's disease (AD. The clearance of Aβ monomer or aggregates is a causal strategy for AD treatment. Microglia and astrocytes are the main macrophages that exert critical neuroprotective roles in the brain. They may effectively clear the toxic accumulation of Aβ at the initial stage of AD, however, their functions are attenuated because of glial overactivation. In this study, we first showed that heptapeptide XD4 activates the class A scavenger receptor (SR-A on the glia by increasing the binding of Aβ to SR-A, thereby promoting glial phagocytosis of Aβ oligomer in microglia and astrocytes and triggering intracellular mitogen-activated protein kinase (MAPK signaling cascades. Moreover, XD4 enhances the internalization of Aβ monomers to microglia and astrocytes through macropinocytosis or SR-A-mediated phagocytosis. Furthermore, XD4 significantly inhibits Aβ oligomer-induced cytotoxicity to glial cells and decreases the production of proinflammatory cytokines, such as TNF-α and IL-1β, in vitro and in vivo. Our findings may provide a novel strategy for AD treatment by activating SR-A.

  10. α7 Nicotinic Receptor Promotes the Neuroprotective Functions of Astrocytes against Oxaliplatin Neurotoxicity

    Directory of Open Access Journals (Sweden)

    Lorenzo Di Cesare Mannelli

    2015-01-01

    Full Text Available Neuropathies are characterized by a complex response of the central nervous system to injuries. Glial cells are recruited to maintain neuronal homeostasis but dysregulated activation leads to pain signaling amplification and reduces the glial neuroprotective power. Recently, we highlighted the property of α7 nicotinic-acetylcholine-receptor (nAChR agonists to relieve pain and induce neuroprotection simultaneously with a strong increase in astrocyte density. Aimed to study the role of α7 nAChR in the neuron-glia cross-talk, we treated primary rat neurons and astrocytes with the neurotoxic anticancer drug oxaliplatin evaluating the effect of the α7 nAChR agonist PNU-282987 (PNU. Oxaliplatin (1 μM, 48 h reduced cell viability and increased caspase-3 activity of neuron monocultures without damaging astrocytes. In cocultures, astrocytes were not able to protect neurons by oxaliplatin even if glial cell metabolism was stimulated (pyruvate increase. On the contrary, the coculture incubation with 10 μM PNU improved neuron viability and inhibited apoptosis. In the absence of astrocytes, the protection disappeared. Furthermore, PNU promoted the release of the anti-inflammatory cytokine TGF-β1 and the expression of the glutamate-detoxifying enzyme glutamine synthetase. The α7 nAChR stimulation protects neurons from oxaliplatin toxicity through an astrocyte-mediated mechanism. α7 nAChR is suggested for recovering the homeostatic role of astrocytes.

  11. Toll-like receptor 4 promotes fibrosis in bleomycin-induced lung injury in mice.

    Science.gov (United States)

    Li, X X; Jiang, D Y; Huang, X X; Guo, S L; Yuan, W; Dai, H P

    2015-12-21

    The specific role of Toll-like receptor 4 (TLR4) in bleomycin-induced lung fibrosis of mice, a model of human idiopathic pulmonary fibrosis, has not been characterized. We injected bleomycin intratracheally into TLR4 knockout (TLR4(-/-)) and wild-type (WT) mice. Twenty-one days after injection, mice were sacrificed and their lungs were harvested for pathological, hydroxyproline, mRNA expression, and collagen I analyses. Body weight changes and mortality were observed. Light microscopy showed that lung fibrosis was minimal in TLR4(-/-) compared to that in WT mice on day 21 after bleomycin instillation. The Ashcroft score was significantly lower in TLR4(-/-) than in WT mice (3.667 ± 0.730 vs 4.945 ± 0.880, P bleomycin injection (0.281 ± 0.022 vs 0.371 ± 0.047, P bleomycin-treated TLR4(-/-) mice expressed significantly lower type I collagen mRNA levels (mesenchymal marker; 11.069 ± 2.627 vs 4.589 ± 1.440, P Bleomycin-treated TLR4(-/-) mice had a significantly lower mortality rate on day 21 than WT mice (33 vs 75%, P 0.05). Thus, bleomycin-induced pulmonary fibrosis is TLR4-dependent and TLR4 promoted fibrosis in bleomycin-challenged mice.

  12. Dmp1 Promoter-Driven Diphtheria Toxin Receptor Transgene Expression Directs Unforeseen Effects in Multiple Tissues

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    Ahmed Al-Jazzar

    2016-12-01

    Full Text Available Mice harbouring a dentin matrix protein 1 (Dmp1 promoter-driven human diphtheria toxin (DT receptor (HDTR transgene (Tg have recently been used to attain targeted ablation of osteocytes by diphtheria toxin (DT treatment in order to define osteocyte function. Use of these Tg mice has asserted mechano- and novel paracrine regulatory osteocyte functions. To explore osteocyte roles fully, we sought to confirm the selectivity of DT effects in these transgenic mice. However, our findings revealed incomplete DT-induced osteocyte ablation, prevalent HDTR misexpression, as well as more prominent histopathological DT-induced changes in multiple organs in Tg than in wild-type (WT littermate mice. Mechanistic evidence for DT action, via prominent regulation of phosphorylation status of elongation factor-2 (EF-2, was also found in many non-skeletal tissues in Tg mice; indicative of direct “off-target” DT action. Finally, very rapid deterioration in health and welfare status in response to DT treatment was observed in these Tg when compared to WT control mice. Together, these data lead us to conclude that alternative models for osteocyte ablation should be sought and caution be exercised when drawing conclusions from experiments using these Tg mice alone.

  13. The Pentapeptide RM-131 Promotes Food Intake and Adiposity in Wildtype Mice but Not in Mice Lacking the Ghrelin Receptor

    DEFF Research Database (Denmark)

    Fischer, Katrin; Finan, Brian; Clemmensen, Christoffer

    2014-01-01

    decreasing energy expenditure and body fat utilization, as defined in rodents. Based on these and additional, beneficial effects on metabolism, the endogenous ghrelin system is considered an attractive target to treat diverse pathological conditions including those associated with eating/wasting disorders......The gastrointestinal peptide hormone ghrelin is the endogenous ligand of the growth hormone secretagogue receptor (a.k.a. ghrelin receptor, GHR). Currently, ghrelin is the only circulating peripheral hormone with the ability to promote a positive energy balance by stimulating food intake while...

  14. Seminal Plasma Proteins as Androgen Receptor Corregulators Promote Prostate Cancer Growth

    Science.gov (United States)

    2016-12-01

    that SgI did not interact with other steroid hormone receptors, including estrogen receptors and glucocorticoid receptor, and did not significantly...estrogen receptor-β, or glucocorticoid receptor. Figure 6. Co-precipitation of AR and SgI. Cell lysates from 293T transfected with pSG5-AR and pSG5-SgI...results suggest that SgI may require not only zinc, as in the case of its physi- ological action [12-16], but also AR to function as a modulator of

  15. Compound A, a Selective Glucocorticoid Receptor Modulator, Enhances Heat Shock Protein Hsp70 Gene Promoter Activation

    Science.gov (United States)

    Beck, Ilse M.; Drebert, Zuzanna J.; Hoya-Arias, Ruben; Bahar, Ali A.; Devos, Michael; Clarisse, Dorien; Desmet, Sofie; Bougarne, Nadia; Ruttens, Bart; Gossye, Valerie; Denecker, Geertrui; Lievens, Sam; Bracke, Marc; Tavernier, Jan; Declercq, Wim; Gevaert, Kris; Berghe, Wim Vanden; Haegeman, Guy; De Bosscher, Karolien

    2013-01-01

    Compound A possesses glucocorticoid receptor (GR)-dependent anti-inflammatory properties. Just like classical GR ligands, Compound A can repress NF-κB-mediated gene expression. However, the monomeric Compound A-activated GR is unable to trigger glucocorticoid response element-regulated gene expression. The heat shock response potently activates heat shock factor 1 (HSF1), upregulates Hsp70, a known GR chaperone, and also modulates various aspects of inflammation. We found that the selective GR modulator Compound A and heat shock trigger similar cellular effects in A549 lung epithelial cells. With regard to their anti-inflammatory mechanism, heat shock and Compound A are both able to reduce TNF-stimulated IκBα degradation and NF-κB p65 nuclear translocation. We established an interaction between Compound A-activated GR and Hsp70, but remarkably, although the presence of the Hsp70 chaperone as such appears pivotal for the Compound A-mediated inflammatory gene repression, subsequent novel Hsp70 protein synthesis is uncoupled from an observed CpdA-induced Hsp70 mRNA upregulation and hence obsolete in mediating CpdA’s anti-inflammatory effect. The lack of a Compound A-induced increase in Hsp70 protein levels in A549 cells is not mediated by a rapid proteasomal degradation of Hsp70 or by a Compound A-induced general block on translation. Similar to heat shock, Compound A can upregulate transcription of Hsp70 genes in various cell lines and BALB/c mice. Interestingly, whereas Compound A-dependent Hsp70 promoter activation is GR-dependent but HSF1-independent, heat shock-induced Hsp70 expression alternatively occurs in a GR-independent and HSF1-dependent manner in A549 lung epithelial cells. PMID:23935933

  16. GLP-1 receptor agonist promotes brown remodelling in mouse white adipose tissue through SIRT1.

    Science.gov (United States)

    Xu, Fen; Lin, Beisi; Zheng, Xiaobin; Chen, Zonglan; Cao, Huanyi; Xu, Haixia; Liang, Hua; Weng, Jianping

    2016-05-01

    Accumulating evidence has revealed the significant role of glucagon-like peptide-1 (GLP-1) in weight loss. Sirtuin 1 (SIRT1) plays a vital role in the regulation of lipid metabolism. Here, we investigated the contribution of lipolytic and oxidative changes in white adipose tissue (WAT) to the weight-lowering effect induced by the GLP-1 receptor (GLP-1R) agonist exenatide (exendin-4) in mice. We also looked at the role of SIRT1 in this process. C57BL/6J mice and Sirt1 (+/-) mice were treated with exenatide (24 nmol/kg) or an NaCl solution (154 mmol/l) control i.p. for 8 weeks while receiving a high-fat diet (HFD) after a 12 week HFD challenge. Systemic phenotypic evaluations were carried out during and after the intervention. A lentivirus-mediated short hairpin (sh)RNA vector of the Sirt1 gene was transfected into differentiated 3T3-L1 adipocytes. An in vitro model system used adipocytes induced from Sirt1-null mouse embryonic fibroblasts (MEFs). Exenatide reduced fat mass and enhanced the lipolytic and oxidative capacity of WAT in diet-induced obese C57BL/6J mice. However, these effects were significantly impaired in Sirt1 (+/-) mice compared with wild-type controls. In vitro, exendin-4 increased lipolysis and fatty acid oxidation by upregulating SIRT1 expression and activity in differentiated 3T3-L1 adipocytes. Conversely, RNA interference (i)-induced knockdown of SIRT1 attenuated the lipolytic and oxidative responses to exendin-4 in differentiated 3T3-L1 adipocytes. Again, these responses were entirely abolished in Sirt1-null MEFs after induction into adipocytes. These data highlight that a GLP-1R agonist promotes brown remodelling of WAT in a SIRT1-dependent manner; this might be one of the mechanisms underlying its effect on weight loss.

  17. DNA Methyltransferase 3B Gene Promoter and Interleukin-1 Receptor Antagonist Polymorphisms in Childhood Immune Thrombocytopenia

    Directory of Open Access Journals (Sweden)

    Margarita Pesmatzoglou

    2012-01-01

    Full Text Available Primary immune thrombocytopenia (ITP is one of the most common blood diseases as well as the commonest acquired bleeding disorder in childhood. Although the etiology of ITP is unclear, in the pathogenesis of the disease, both environmental and genetic factors including polymorphisms of TNF-a, IL-10, and IL-4 genes have been suggested to be involved. In this study, we investigated the rs2424913 single-nucleotide polymorphism (SNP (C46359T in DNA methyltransferase 3B (DNMT3B gene promoter and the VNTR polymorphism of IL-1 receptor antagonist (IL-1 Ra intron-2 in 32 children (17 boys with the diagnosis of ITP and 64 healthy individuals. No significant differences were found in the genotype distribution of DNMT3B polymorphism between the children with ITP and the control group, whereas the frequency of allele T appeared significantly increased in children with ITP (P = 0.03, OR = 2, 95% CI: 1.06–3.94. In case of IL-1 Ra polymorphism, children with ITP had a significantly higher frequency of genotype I/II, compared to control group (P = 0.043, OR = 2.60, 95% CI: 1.02–6.50. Moreover, genotype I/I as well as allele I was overrepresented in the control group, suggesting that allele I may have a decreased risk for development of ITP. Our findings suggest that rs2424913 DNMT3B SNP as well as IL-1 Ra VNTR polymorphism may contribute to the susceptibility to ITP.

  18. Melanocortin 1 Receptor Deficiency Promotes Atherosclerosis in Apolipoprotein E−/− Mice

    Science.gov (United States)

    Kadiri, James J.; Velasco-Delgado, Mauricio; Nuutinen, Salla; Viitala, Miro; Hollmén, Maija; Rami, Martina; Savontaus, Eriika; Steffens, Sabine

    2018-01-01

    Objective— The MC1-R (melanocortin 1 receptor) is expressed by monocytes and macrophages where it mediates anti-inflammatory actions. MC1-R also protects against macrophage foam cell formation primarily by promoting cholesterol efflux through the ABCA1 (ATP-binding cassette transporter subfamily A member 1) and ABCG1 (ATP-binding cassette transporter subfamily G member 1). In this study, we aimed to investigate whether global deficiency in MC1-R signaling affects the development of atherosclerosis. Approach and Results— Apoe−/− (apolipoprotein E deficient) mice were crossed with recessive yellow (Mc1re/e) mice carrying dysfunctional MC1-R and fed a high-fat diet to induce atherosclerosis. Apoe−/− Mc1re/e mice developed significantly larger atherosclerotic lesions in the aortic sinus and in the whole aorta compared with Apoe−/− controls. In terms of plaque composition, MC1-R deficiency was associated with less collagen and smooth muscle cells and increased necrotic core, indicative of more vulnerable lesions. These changes were accompanied by reduced Abca1 and Abcg1 expression in the aorta. Furthermore, Apoe−/− Mc1re/e mice showed a defect in bile acid metabolism that aggravated high-fat diet–induced hypercholesterolemia and hepatic lipid accumulation. Flow cytometric analysis of leukocyte profile revealed that dysfunctional MC1-R enhanced arterial accumulation of classical Ly6Chigh monocytes and macrophages, effects that were evident in mice fed a normal chow diet but not under high-fat diet conditions. In support of enhanced arterial recruitment of Ly6Chigh monocytes, these cells had increased expression of L-selectin and P-selectin glycoprotein ligand 1. Conclusions— The present study highlights the importance of MC1-R in the development of atherosclerosis. Deficiency in MC1-R signaling exacerbates atherosclerosis by disturbing cholesterol handling and by increasing arterial monocyte accumulation. PMID:29284608

  19. Melanocortin 1 Receptor Deficiency Promotes Atherosclerosis in Apolipoprotein E-/-Mice.

    Science.gov (United States)

    Rinne, Petteri; Kadiri, James J; Velasco-Delgado, Mauricio; Nuutinen, Salla; Viitala, Miro; Hollmén, Maija; Rami, Martina; Savontaus, Eriika; Steffens, Sabine

    2018-02-01

    The MC1-R (melanocortin 1 receptor) is expressed by monocytes and macrophages where it mediates anti-inflammatory actions. MC1-R also protects against macrophage foam cell formation primarily by promoting cholesterol efflux through the ABCA1 (ATP-binding cassette transporter subfamily A member 1) and ABCG1 (ATP-binding cassette transporter subfamily G member 1). In this study, we aimed to investigate whether global deficiency in MC1-R signaling affects the development of atherosclerosis. Apoe -/- (apolipoprotein E deficient) mice were crossed with recessive yellow (Mc1r e/e ) mice carrying dysfunctional MC1-R and fed a high-fat diet to induce atherosclerosis. Apoe -/- Mc1r e/e mice developed significantly larger atherosclerotic lesions in the aortic sinus and in the whole aorta compared with Apoe -/- controls. In terms of plaque composition, MC1-R deficiency was associated with less collagen and smooth muscle cells and increased necrotic core, indicative of more vulnerable lesions. These changes were accompanied by reduced Abca1 and Abcg1 expression in the aorta. Furthermore, Apoe -/- Mc1r e/e mice showed a defect in bile acid metabolism that aggravated high-fat diet-induced hypercholesterolemia and hepatic lipid accumulation. Flow cytometric analysis of leukocyte profile revealed that dysfunctional MC1-R enhanced arterial accumulation of classical Ly6C high monocytes and macrophages, effects that were evident in mice fed a normal chow diet but not under high-fat diet conditions. In support of enhanced arterial recruitment of Ly6C high monocytes, these cells had increased expression of L-selectin and P-selectin glycoprotein ligand 1. The present study highlights the importance of MC1-R in the development of atherosclerosis. Deficiency in MC1-R signaling exacerbates atherosclerosis by disturbing cholesterol handling and by increasing arterial monocyte accumulation. © 2017 The Authors.

  20. Progesterone receptor isoform-specific promoter methylation: association of PRA promoter methylation with worse outcome in breast cancer patients.

    Science.gov (United States)

    Pathiraja, Thushangi N; Shetty, Priya B; Jelinek, Jaroslav; He, Rong; Hartmaier, Ryan; Margossian, Astrid L; Hilsenbeck, Susan G; Issa, Jean-Pierre J; Oesterreich, Steffi

    2011-06-15

    ERα and PR levels are critical determinants for breast cancer prognosis and response to endocrine therapy. Although PR is known to be silenced by methylation of its promoter, few studies have correlated methylation with PR levels and outcome in breast cancer. There is only one previous small study comparing methylation of the two PR isoforms, PRA and PRB, which are expressed from different promoters, and finally, there is no prior knowledge of associations between isoform-specific methylation and outcome. We conducted a cohort-based study to test for associations between PRA and PRB methylation, expression, and clinical outcome in tamoxifen-treated patients (n = 500), and in patients who underwent surgery only (n = 500). Methylation and PR levels were measured by bisulfite pyrosequencing and ligand-binding assay, respectively. Low PR levels were significantly associated with worse outcome in all patients. PRA and PRB promoters were methylated in 9.6% and 14.1% of the breast tumors, respectively. The majority (74%) of PR-negative tumors were not methylated despite the significant inverse correlation of methylation and PR levels. PRA methylation was significantly associated with PRB methylation, although a subset of tumors had PRA only (3.9%) or PRB only (8.3%) methylated. Methylation of PRA, but not PRB was significantly associated with worse outcome in the tamoxifen-treated group. Mechanisms other than promoter methylation may be more dominant for loss of PR. Isoform-specific methylation events suggest independent regulation of PRA and PRB. Finally, this article shows for the first time that PRA methylation plays a unique role in tamoxifen-resistant breast cancer. ©2011 AACR.

  1. Progesterone receptor isoform-specific promoter methylation — Association of PRA promoter methylation with worse outcome in breast cancer patients

    Science.gov (United States)

    Pathiraja, Thushangi N; Shetty, Priya B; Jelinek, Jaroslav; He, Rong; Hartmaier, Ryan; Margossian, Astrid L; Hilsenbeck, Susan G; Issa, Jean-Pierre J; Oesterreich, Steffi

    2011-01-01

    Purpose ERα and PR levels are critical determinants for breast cancer prognosis and response to endocrine therapy. Although PR is known to be silenced by methylation of its promoter, few studies have correlated methylation with PR levels and outcome in breast cancer. There is only one previous small study comparing methylation of the two PR isoforms, PRA and PRB, which are expressed from different promoters, and finally, there is no prior knowledge of associations between isoform-specific methylation and outcome. Experimental Design We conducted a cohort-based study to test for associations between PRA and PRB methylation, expression, and clinical outcome in tamoxifen-treated patients (n=500), and in patients who underwent surgery only (n=500). Methylation and PR levels were measured by bisulfite pyrosequencing and ligand binding assay, respectively. Results Low PR levels were significantly associated with worse outcome in all patients. PRA and PRB promoters were methylated in 9.6% and 14.1% of the breast tumors, respectively. The majority (74%) of PR-negative tumors were not methylated despite the significant inverse correlation of methylation and PR levels. PRA methylation was significantly associated with PRB methylation, although a subset of tumors had PRA only (3.9%) or PRB only (8.3%) methylated. Methylation of PRA, but not PRB was significantly associated with worse outcome in the tamoxifen treated group. Conclusions Mechanisms other than promoter methylation may be more dominant for loss of PR. Isoform-specific methylation events suggest independent regulation of PRA and PRB. Finally, this study shows for the first time that PRA methylation plays a unique role in tamoxifen-resistant breast cancer. PMID:21459801

  2. Lectin-like oxidized low-density lipoprotein receptor-1 promotes endothelial dysfunction in LDL receptor knockout background.

    Science.gov (United States)

    Hofmann, Anja; Brunssen, Coy; Poitz, David M; Langbein, Heike; Strasser, Ruth H; Henle, Thomas; Ravens, Ursula; Morawietz, Henning

    2017-11-01

    Lectin-like oxidized low-density lipoprotein receptor-1 (LOX-1) is the major receptor for oxidized LDL in endothelial cells. LOX-1 is highly expressed in atherosclerotic plaques. The impact of LOX-1 on development of endothelial dysfunction in large vessels in absence or presence of atherosclerosis-prone conditions has not been studied to date. Mice with endothelial cell-specific LOX-1 overexpression (bLOX-1tg) were analyzed. Wild-type (WT) mice served as controls. In addition, bLOX-1tg mice were crossed with LDL receptor knockout (Ldlr -/- ) mice. All mice were fed a western-type diet (WD) or control diet (CD) for 20 weeks. Afterwards, endothelial function was analyzed ex vivo in thoracic aortas using a Mulvany myograph. WD induced hypertriglyceridemia (bLOX-1tg: 1.6-fold; WT: 1.4-fold) and hypercholesterolemia (P LDL-cholesterol (∼9-fold) compared to WT and bLOX-1tg mice on WD. Endothelial function in response to WD was impaired in bLOX-1tg/Ldlr -/- mice (Eff max : 56.7 ± 23.0%) compared to WT (Eff max : 88.2 ± 15.8%, P < 0.001), bLOX-1tg (Eff max : 76.7 ± 12.9%, P < 0.05) and Ldlr -/- mice (Eff max : 70.1 ± 13.1%, P < 0.05). No differences between WT, bLOX-1tg and Ldlr -/- mice were detectable when comparing all genotypes. Endothelial LOX-1 overexpression in an atherosclerosis-prone background impairs endothelial function, proving its importance in the development of atherosclerosis. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Farnesoid X Receptor Activation Promotes Hepatic Amino Acid Catabolism and Ammonium Clearance in Mice

    NARCIS (Netherlands)

    Massafra, Vittoria; Milona, Alexandra; Vos, Harmjan R; Ramos, Rúben J J; Gerrits, Johan; Willemsen, Ellen C L; Ramos Pittol, José M; Ijssennagger, Noortje; Houweling, Martin; Prinsen, Hubertus C M T; Verhoeven-Duif, Nanda M; Burgering, Boudewijn M T; van Mil, Saskia W C

    2017-01-01

    BACKGROUND & AIMS: The nuclear receptor subfamily 1 group H member 4 (NR1H4 or farnesoid X receptor [FXR]) regulates bile acid synthesis, transport, and catabolism. FXR also regulates postprandial lipid and glucose metabolism. We performed quantitative proteomic analyses of liver tissues from mice

  4. 3-methylcholanthrene induces differential recruitment of aryl hydrocarbon receptor to human promoters

    DEFF Research Database (Denmark)

    Pansoy, Andrea; Ahmed, Shaimaa; Valen, Eivind

    2010-01-01

    The aryl hydrocarbon receptor (AHR) is a ligand-activated protein that mediates the toxic actions of polycyclic aromatic and halogenated compounds. Identifying genes directly regulated by AHR is important in understanding the pathways regulated by this receptor. Here we used chromatin immunopreci...

  5. A growth hormone receptor SNP promotes lung cancer by impairment of SOCS2-mediated degradation

    DEFF Research Database (Denmark)

    Chhabra, Y.; Wong, H. Y.; Nikolajsen, Louise Fletcher

    2018-01-01

    binding to the GHR is impaired by a threonine substitution at Pro 495. This results in decreased internalisation and degradation of the receptor evident in TIRF microscopy and by measurement of mature (surface) receptor expression. Mutational analysis showed that the residue at position 495 impairs SOCS2...

  6. A new agonist of the erythropoietin receptor, Epobis, induces neurite outgrowth and promotes neuronal survival

    DEFF Research Database (Denmark)

    Pankratova, Stanislava; Gu, Bing; Kiryushko, Darya

    2012-01-01

    Apart from its hematopoietic activity, erythropoietin (EPO) is also known as a tissue-protective cytokine. In the brain, EPO and its receptor are up-regulated in response to insult and exert pro-survival effects. EPO binds to its receptor (EPOR) via high- and low-affinity binding sites (Sites 1 a...

  7. The adiponectin receptor homologs in C. elegans promote energy utilization and homeostasis

    DEFF Research Database (Denmark)

    Svensson, Emma; Olsen, Louise Cathrine Braun; Mörck, Catarina

    2011-01-01

    Adiponectin is an adipokine with insulin-sensitising actions in vertebrates. Its receptors, AdipoR1 and AdipoR2, are PAQR-type proteins with 7-transmembrane domains and topologies reversed that of GPCR's, i.e. their C-termini are extracellular. We identified three adiponectin receptor homologs...... when combined with the paqr-1 mutation. paqr-2 mutants are also synthetic lethal with mutations in nhr-49, sbp-1 and fat-6, which are C. elegans homologs of nuclear hormone receptors, SREBP and FAT-6 (a Δ9 desaturase), respectively. Like paqr-2, paqr-1 is also synthetic lethal with sbp-1. Mutations...... in aak-2, the C. elegans homolog of AMPK, or nhr-80, another nuclear hormone receptor gene, suppress the growth phenotype of paqr-2 mutants, probably because they restore the balance between energy expenditure and storage. We conclude that paqr-1 and paqr-2 are receptors that regulate fatty acid...

  8. Hematopoietic androgen receptor deficiency promotes visceral fat deposition in male mice without impairing glucose homeostasis.

    Science.gov (United States)

    Rubinow, K B; Wang, S; den Hartigh, L J; Subramanian, S; Morton, G J; Buaas, F W; Lamont, D; Gray, N; Braun, R E; Page, S T

    2015-07-01

    Androgen deficiency in men increases body fat, but the mechanisms by which testosterone suppresses fat deposition have not been elucidated fully. Adipose tissue macrophages express the androgen receptor (AR) and regulate adipose tissue remodeling. Thus, testosterone signaling in macrophages could alter the paracrine function of these cells and thereby contribute to the metabolic effects of androgens in men. A metabolic phenotyping study was performed to determine whether the loss of AR signaling in hematopoietic cells results in greater fat accumulation in male mice. C57BL/6J male mice (ages 12-14 weeks) underwent bone marrow transplant from either wild-type (WT) or AR knockout (ARKO) donors (n = 11-13 per group). Mice were fed a high-fat diet (60% fat) for 16 weeks. At baseline, 8 and 16 weeks, glucose and insulin tolerance tests were performed, and body composition was analyzed with fat-water imaging by MRI. No differences in body weight were observed between mice transplanted with WT bone marrow [WT(WTbm)] or ARKO bone marrow [WT(ARKObm)] prior to initiation of the high-fat diet. After 8 weeks of high-fat feeding, WT(ARKObm) mice exhibited significantly more visceral and total fat mass than WT(WTbm) animals. Despite this, no differences between groups were observed in glucose tolerance, insulin sensitivity, or plasma concentrations of insulin, glucose, leptin, or cholesterol, although WT(ARKObm) mice had higher plasma levels of adiponectin. Resultant data indicate that AR signaling in hematopoietic cells influences body fat distribution in male mice, and the absence of hematopoietic AR plays a permissive role in visceral fat accumulation. These findings demonstrate a metabolic role for AR signaling in marrow-derived cells and suggest a novel mechanism by which androgen deficiency in men might promote increased adiposity. The relative contributions of AR signaling in macrophages and other marrow-derived cells require further investigation. © 2015 American

  9. The class I scavenger receptor CD163 promotes internalization of ADAMTS13 by macrophages.

    Science.gov (United States)

    Verbij, Fabian C; Sorvillo, Nicoletta; Kaijen, Paul H P; Hrdinova, Johana; Peyron, Ivan; Fijnheer, Rob; Ten Brinke, Anja; Meijer, Alexander B; van Alphen, Floris P J; van den Berg, Timo K; Graversen, Jonas J H; Moestrup, Soren K; Voorberg, Jan

    2017-01-24

    Internalization of ADAMTS13 by macrophages may contribute to its clearance from the circulation. Here we investigated endocytic mechanisms that contribute to the uptake of ADAMTS13 by macrophages. Human monocyte-derived macrophages were used to monitor the uptake of fluorescently labeled recombinant ADAMTS13 by flow cytometry. Internalization of ADAMTS13 was blocked upon addition of the cell-permeable dynamin inhibitor dynasore. Partial blocking of ADAMTS13 uptake was observed by using mannan; however, uptake was not affected by an antibody that blocked binding to the macrophage mannose receptor CD206, which suggests that other endocytic receptors contribute to the internalization of ADAMTS13 by macrophages. A pull-down with ADAMTS13 and subsequent mass spectrometric analysis identified the class I scavenger receptor CD163 as a candidate receptor for ADAMTS13. Blocking experiments with monoclonal anti-CD163 antibody EDHu-1 resulted in decreased ADAMTS13 internalization by macrophages. Pronounced inhibition of ADAMTS13 uptake by EDHu-1 was observed in CD163 high-expressing macrophages. In agreement with these findings, CD163-expressing Chinese hamster ovary cells were capable of rapidly internalizing ADAMTS13. Surface plasmon resonance revealed binding of ADAMTS13 to scavenger receptor cysteine-rich domains 1-9 and 1-5 of CD163. Taken together, our data identify CD163 as a major endocytic receptor for ADAMTS13 on macrophages.

  10. Environmental Endocrine Disruptors Promote Adipogenesis in the 3T3-L1 Cell Line through Glucocorticoid Receptor Activation

    Science.gov (United States)

    Sargis, Robert M.; Johnson, Daniel N.; Choudhury, Rashikh A.; Brady, Matthew J.

    2014-01-01

    The burgeoning obesity and diabetes epidemics threaten health worldwide, yet the molecular mechanisms underlying these phenomena are incompletely understood. Recently, attention has focused on the potential contributions of environmental pollutants that act as endocrine disrupting chemicals (EDCs) in the pathogenesis of metabolic diseases. Because glucocorticoid signaling is central to adipocyte differentiation, the ability of EDCs to stimulate the glucocorticoid receptor (GR) and drive adipogenesis was assessed in the 3T3-L1 cell line. Various EDCs were screened for glucocorticoid-like activity using a luciferase reporter construct, and four (bisphenol A (BPA), dicyclohexyl phthalate (DCHP), endrin, and tolylfluanid (TF)) were shown to significantly stimulate GR without significant activation of the peroxisome proliferator-activated receptor-γ. 3T3-L1 preadipocytes were then treated with EDCs and a weak differentiation cocktail containing dehydrocorticosterone (DHC) in place of the synthetic dexamethasone. The capacity of these compounds to promote adipogenesis was assessed by quantitative oil red O staining and immunoblotting for adipocyte-specific proteins. The four EDCs increased lipid accumulation in the differentiating adipocytes and also upregulated the expression of adipocytic proteins. Interestingly, proadipogenic effects were observed at picomolar concentrations for several of the EDCs. Because there was no detectable adipogenesis when the preadipocytes were treated with compounds alone, the EDCs are likely promoting adipocyte differentiation by synergizing with agents present in the differentiation cocktail. Thus, EDCs are able to promote adipogenesis through the activation of the GR, further implicating these compounds in the rising rates of obesity and diabetes. PMID:19927138

  11. The Toll-like receptor 5 ligand flagellin promotes asthma by priming allergic responses to indoor allergens.

    Science.gov (United States)

    Wilson, Rhonda H; Maruoka, Shuichiro; Whitehead, Gregory S; Foley, Julie F; Flake, Gordon P; Sever, Michelle L; Zeldin, Darryl C; Kraft, Monica; Garantziotis, Stavros; Nakano, Hideki; Cook, Donald N

    2012-11-01

    Allergic asthma is a complex disease characterized by eosinophilic pulmonary inflammation, mucus production and reversible airway obstruction. Exposure to indoor allergens is a risk factor for asthma, but this disease is also associated with high household levels of total and particularly Gram-negative bacteria. The ability of bacterial products to act as adjuvants suggests they might promote asthma by priming allergic sensitization to inhaled allergens. In support of this idea, house dust extracts (HDEs) can activate antigen-presenting dendritic cells (DCs) in vitro and promote allergic sensitization to inhaled innocuous proteins in vivo. It is unknown which microbial products provide most of the adjuvant activity in HDEs. A screen for adjuvant activity of microbial products revealed that the bacterial protein flagellin (FLA) stimulated strong allergic airway responses to an innocuous inhaled protein, ovalbumin (OVA). Moreover, Toll-like receptor 5 (TLR5), the mammalian receptor for FLA, was required for priming strong allergic responses to natural indoor allergens present in HDEs. In addition, individuals with asthma have higher serum levels of FLA-specific antibodies as compared to nonasthmatic individuals. Together, these findings suggest that household FLA promotes the development of allergic asthma by TLR5-dependent priming of allergic responses to indoor allergens.

  12. Signaling of ghrelin and its functional receptor, the growth hormone secretagogue receptor, promote tumor growth in glioblastomas.

    Science.gov (United States)

    Okada, Yousuke; Sugita, Yasuo; Ohshima, Koichi; Morioka, Motohiro; Komaki, Satoru; Miyoshi, Junko; Abe, Hideyuki

    2016-12-01

    Ghrelin is a 28-amino-acid peptide that is the endogenous ligand for the pituitary growth hormone secretagogue receptor (GHS-R). Ghrelin is mainly produced from the stomach, but it is also expressed by various other tissues, including the CNS under normal conditions. Physiologically, ghrelin regulates appetite, gut motility, and GH release from the anterior pituitary, as well as cardiovascular and immune systems. Recent studies also indicate that ghrelin and GHS-R may play an important autocrine/paracrine role in neoplastic conditions. In order to clarify the role of ghrelin/GHS-R in gliomas, the present study assessed the expression of ghrelin and its functional receptor, GHS-R1a, in 39 glioblastomas (GBs), 13 anaplastic astrocytomas (AAs) and 11 diffuse astrocytomas (DAs) using immunohistochemical analyses. Immunohistochemical staining was evaluated as follows: no staining; 1+, 0-10% positive cells; 2+, 10-50% positive cells; 3+, >50% positive cells. Ghrelin expression was detected in 52 of 63 cases of which 38, 13 and one were scored as 3+, 2+ and 1+, respectively. GHS-R1a expression was detected in 45 of 63 cases of which 29, 15 and one were scored as 3+, 2+ and 1+, respectively. Ghrelin immunoreactivity was observed in 38 of 39 GBs, 12 of 13 AAs and two of 11 DAs. GHS-R1a immunoreactivity was observed in 39 of 39 GBs, five of 13 AAs, and one of 11 DAs. AAs and GBs showed moderate or strong immunostaining of ghrelin/GHS-R1a in the tumor cells and in proliferating microvessels. Patients were classified into lower to moderate-score, and high-score ghrelin/GHS-R categories according to the principal component and cluster analyses. Multivariate analysis of overall survival indicated that there was a significant difference (P = 0.0001) in the survival rate between these two groups. The combined results indicated that expression of the ghrelin/GHS-R1a axis increases the growth of AAs and GBs through an autocrine/paracrine mechanism. © 2016 Japanese Society of

  13. Methylation of the claudin 1 promoter is associated with loss of expression in estrogen receptor positive breast cancer.

    Directory of Open Access Journals (Sweden)

    Francescopaolo Di Cello

    Full Text Available Downregulation of the tight junction protein claudin 1 is a frequent event in breast cancer and is associated with recurrence, metastasis, and reduced survival, suggesting a tumor suppressor role for this protein. Tumor suppressor genes are often epigenetically silenced in cancer. Downregulation of claudin 1 via DNA promoter methylation may thus be an important determinant in breast cancer development and progression. To investigate if silencing of claudin 1 has an epigenetic etiology in breast cancer we compared gene expression and methylation data from 217 breast cancer samples and 40 matched normal samples available through the Cancer Genome Atlas (TCGA. Moreover, we analyzed claudin 1 expression and methylation in 26 breast cancer cell lines. We found that methylation of the claudin 1 promoter CpG island is relatively frequent in estrogen receptor positive (ER+ breast cancer and is associated with low claudin 1 expression. In contrast, the claudin 1 promoter was not methylated in most of the ER-breast cancers samples and some of these tumors overexpress claudin 1. In addition, we observed that the demethylating agents, azacitidine and decitabine can upregulate claudin 1 expression in breast cancer cell lines that have a methylated claudin 1 promoter. Taken together, our results indicate that DNA promoter methylation is causally associated with downregulation of claudin 1 in a subgroup of breast cancer that includes mostly ER+ tumors, and suggest that epigenetic therapy to restore claudin 1 expression might represent a viable therapeutic strategy in this subtype of breast cancer.

  14. P2X1 stimulation promotes thrombin receptor-mediated platelet aggregation.

    Science.gov (United States)

    Erhardt, J A; Toomey, J R; Douglas, S A; Johns, D G

    2006-04-01

    P2X1 receptors are ATP-gated channel demonstrated to be involved in multiple platelet responses, although in vitro analysis has been complicated by the effects of rapid desensitization. To further investigate potential roles of P2X1 receptors in platelet activation, the current study employed methods which maximally preserved P2X1 functionality. In preliminary in vivo studies, P2X1-deficiency reduced thrombus formation following the laser-induced, but not FeCl3-induced injury. Given the multiple potential mechanisms involved in thrombus formation in vivo, including tissue-factor/thrombin generation pathways, subsequent studies were designed to investigate the effects of P2X1 inhibition or stimulation on platelet activation in vitro; specifically, the interaction of P2X1 with thrombin receptor stimulation. Aggregation initiated by low/threshold levels of a protease-activated receptor (PAR)4 agonist was reduced in P2X1-deficient murine platelets, and inhibition of P2X1 in wild-type platelets similarly reduced PAR4-mediated aggregation. In human platelets, aggregation to low/threshold stimulation of PAR1 was inhibited with the P2X1 antagonist MRS2159. In addition, P2X1 stimulation primed human platelet responses, such that subsequent sub-threshold PAR1 responses were converted into significant aggregation. Selective ADP receptor inhibitors attenuated P2X1-mediated priming, suggesting that the synergy between P2X1 and sub-threshold PAR1 stimulation was in part because of enhanced granular release of ADP. Overall, the present study defines a novel interaction between platelet P2X1 and thrombin receptors, with P2X1 functioning to amplify aggregation responses at low levels of thrombin receptor stimulation.

  15. Hemin inhibits internalization of transferrin by reticulocytes and promotes phosphorylation of the membrane transferrin receptor

    International Nuclear Information System (INIS)

    Cox, T.M.; O'Donnell, M.W.; Aisen, P.; London, I.M.

    1985-01-01

    Addition of hemin to reticulocytes inhibits incorporation of iron from transferrin. Heme also regulates protein synthesis in immature erythroid cells through its effects on phosphorylation of the initiation factor eIF-2. The authors have examined its effects on endocytosis of iron-transferrin and phosphorylation of the transferrin receptor. Hemin reduced iron transport but increased cell-associated transferrin. During uptake of 125 I-labeled transferrin in the steady state, the use of a washing technique to dissociate bound transferrin on the cell membrane showed that radioligand accumulated on the surface of hemin-treated cells. Receptor phosphorylation was investigated by immunoprecipitation of reticulocyte extracts after metabolic labeling with [ 32 P]P/sub i/. In the absence of ligand, phosphorylated receptor was chiefly localized on cell stroma. Exposure to transferrin increased cytosolic phosphorylated receptor from 15-30% to approximately 50% of the total, an effect overcome by hemin treatment. The findings suggest a possible relationship of phosphorylation to endocytosis of the transferrin receptor in reticulocytes

  16. The CytR repressor antagonizes cyclic AMP-cyclic AMP receptor protein activation of the deoCp2 promoter of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Søgaard-Andersen, L; Martinussen, J; Møllegaard, N E

    1990-01-01

    We have investigated the regulation of the Escherichia coli deoCp2 promoter by the CytR repressor and the cyclic AMP (cAMP) receptor protein (CRP) complexed to cAMP. Promoter regions controlled by these two proteins characteristically contain tandem cAMP-CRP binding sites. Here we show that (i) Cyt...

  17. Mutation of the SHP-2 binding site in growth hormone (GH) receptor prolongs GH-promoted tyrosyl phosphorylation of GH receptor, JAK2, and STAT5B

    DEFF Research Database (Denmark)

    Stofega, M R; Herrington, J; Billestrup, Nils

    2000-01-01

    Binding of GH to GH receptor (GHR) rapidly and transiently activates multiple signal transduction pathways that contribute to the growth-promoting and metabolic effects of GH. While the events that initiate GH signal transduction, such as activation of the Janus tyrosine kinase JAK2, are beginning...... to be understood, the signaling events that terminate GH signaling, such as dephosphorylation of tyrosyl-phosphorylated signaling molecules, are poorly understood. In this report, we examine the role of the SH2 (Src homology-2) domain-containing protein tyrosine phosphatase SHP-2 in GH signaling. We demonstrate...... that the SH2 domains of SHP-2 bind directly to tyrosyl phosphorylated GHR from GH-treated cells. Tyrosine-to-phenylalanine mutation of tyrosine 595 of rat GHR greatly diminishes association of the SH2 domains of SHP-2 with GHR, and tyrosine-to-phenylalanine mutation of tyrosine 487 partially reduces...

  18. Oncogenic tyrosine kinase NPM-ALK induces expression of the growth-promoting receptor ICOS

    DEFF Research Database (Denmark)

    Zhang, Qian; Wang, HongYi; Kantekure, Kanchan

    2011-01-01

    Here we report that T-cell lymphoma cells carrying the NPM-ALK fusion protein (ALK(+) TCL) frequently express the cell-stimulatory receptor ICOS. ICOS expression in ALK(+) TCL is moderate and strictly dependent on the expression and enzymatic activity of NPM-ALK. NPM-ALK induces ICOS expression v...

  19. Enhanced AMPA receptor function promotes cerebellar long-term depression rather than potentiation

    NARCIS (Netherlands)

    B.J. van Beugen (Boeke); X. Qiao (Xin); D.H. Simmons (Dana H.); C.I. de Zeeuw (Chris); C.R.W. Hansel (Christian)

    2014-01-01

    textabstractAmpakines are allosteric modulators of AMPA receptors that facilitate hippocampal long-term potentiation (LTP) and learning, and have been considered for the treatment of cognition and memory deficits. Here, we show that the ampakine CX546 raises the amplitude and slows the decay time of

  20. Enhanced AMPA Receptor Function Promotes Cerebellar Long-Term Depression Rather than Potentiation

    Science.gov (United States)

    van Beugen, Boeke J.; Qiao, Xin; Simmons, Dana H.; De Zeeuw, Chris I.; Hansel, Christian

    2014-01-01

    Ampakines are allosteric modulators of AMPA receptors that facilitate hippocampal long-term potentiation (LTP) and learning, and have been considered for the treatment of cognition and memory deficits. Here, we show that the ampakine CX546 raises the amplitude and slows the decay time of excitatory postsynaptic currents (EPSCs) at cerebellar…

  1. Enhanced AMPA receptor function promotes cerebellar long-term depression rather than potentiation

    NARCIS (Netherlands)

    van Beugen, Boeke J; Qiao, Xin; Simmons, Dana H; De Zeeuw, Chris I; Hansel, Christian

    2014-01-01

    Ampakines are allosteric modulators of AMPA receptors that facilitate hippocampal long-term potentiation (LTP) and learning, and have been considered for the treatment of cognition and memory deficits. Here, we show that the ampakine CX546 raises the amplitude and slows the decay time of excitatory

  2. B1 but not B2 bradykinin receptor agonists promote DU145 prostate ...

    African Journals Online (AJOL)

    Background: The kallikrein-kinin system (KKS) is an endogenous pathway involved in angiogenesis and tumourigenesis, both vital for cancer growth and progression. Objectives: To investigate the effect of two bradykinin receptor (B1R and B2R) agonists on growth and motility of prostate tumour (DU145) and ...

  3. D1-D2 Dopamine Receptor Synergy Promotes Calcium Signaling via Multiple Mechanisms

    Science.gov (United States)

    Chun, Lani S.; Free, R. Benjamin; Doyle, Trevor B.; Huang, Xi-Ping; Rankin, Michele L.

    2013-01-01

    The D1 dopamine receptor (D1R) has been proposed to form a hetero-oligomer with the D2 dopamine receptor (D2R), which in turn results in a complex that couples to phospholipase C–mediated intracellular calcium release. We have sought to elucidate the pharmacology and mechanism of action of this putative signaling pathway. Dopamine dose-response curves assaying intracellular calcium mobilization in cells heterologously expressing the D1 and D2 subtypes, either alone or in combination, and using subtype selective ligands revealed that concurrent stimulation is required for coupling. Surprisingly, characterization of a putative D1-D2 heteromer-selective ligand, 6-chloro-2,3,4,5-tetrahydro-3-methyl-1-(3-methylphenyl)-1H-3-benzazepine-7,8-diol (SKF83959), found no stimulation of calcium release, but it did find a broad range of cross-reactivity with other G protein–coupled receptors. In contrast, SKF83959 appeared to be an antagonist of calcium mobilization. Overexpression of Gqα with the D1 and D2 dopamine receptors enhanced the dopamine-stimulated calcium response. However, this was also observed in cells expressing Gqα with only the D1R. Inactivation of Gi or Gs with pertussis or cholera toxin, respectively, largely, but not entirely, reduced the calcium response in D1R and D2R cotransfected cells. Moreover, sequestration of Gβγ subunits through overexpression of G protein receptor kinase 2 mutants either completely or largely eliminated dopamine-stimulated calcium mobilization. Our data suggest that the mechanism of D1R/D2R–mediated calcium signaling involves more than receptor-mediated Gq protein activation, may largely involve downstream signaling pathways, and may not be completely heteromer-specific. In addition, SKF83959 may not exhibit selective activation of D1-D2 heteromers, and its significant cross-reactivity to other receptors warrants careful interpretation of its use in vivo. PMID:23680635

  4. Orexin receptor antagonists differ from standard sleep drugs by promoting sleep at doses that do not disrupt cognition.

    Science.gov (United States)

    Uslaner, Jason M; Tye, Spencer J; Eddins, Donnie M; Wang, Xiaohai; Fox, Steven V; Savitz, Alan T; Binns, Jacquelyn; Cannon, Christopher E; Garson, Susan L; Yao, Lihang; Hodgson, Robert; Stevens, Joanne; Bowlby, Mark R; Tannenbaum, Pamela L; Brunner, Joseph; Mcdonald, Terrence P; Gotter, Anthony L; Kuduk, Scott D; Coleman, Paul J; Winrow, Christopher J; Renger, John J

    2013-04-03

    Current treatments for insomnia, such as zolpidem (Ambien) and eszopiclone (Lunesta), are γ-aminobutyric acid type A (GABAA)-positive allosteric modulators that carry a number of side effects including the potential to disrupt cognition. In an effort to develop better tolerated medicines, we have identified dual orexin 1 and 2 receptor antagonists (DORAs), which promote sleep in preclinical animal models and humans. We compare the effects of orally administered eszopiclone, zolpidem, and diazepam to the dual orexin receptor antagonist DORA-22 on sleep and the novel object recognition test in rat, and on sleep and two cognition tests (delayed match to sample and serial choice reaction time) in the rhesus monkey. Each compound's minimal dose that promoted sleep versus the minimal dose that exerted deficits in these cognitive tests was determined, and a therapeutic margin was established. We found that DORA-22 has a wider therapeutic margin for sleep versus cognitive impairment in rat and rhesus monkey compared to the other compounds tested. These data were further supported with the demonstration of a wider therapeutic margin for DORA-22 compared to the other compounds on sleep versus the expression of hippocampal activity-regulated cytoskeletal-associated protein (Arc), an immediate-early gene product involved in synaptic plasticity. These findings suggest that DORAs might provide an effective treatment for insomnia with a greater therapeutic margin for sleep versus cognitive disturbances compared to the GABAA-positive allosteric modulators currently in use.

  5. Genetic basis of olfactory cognition: extremely high level of DNA sequence polymorphism in promoter regions of the human olfactory receptor genes revealed using the 1000 Genomes Project dataset.

    Science.gov (United States)

    Ignatieva, Elena V; Levitsky, Victor G; Yudin, Nikolay S; Moshkin, Mikhail P; Kolchanov, Nikolay A

    2014-01-01

    The molecular mechanism of olfactory cognition is very complicated. Olfactory cognition is initiated by olfactory receptor proteins (odorant receptors), which are activated by olfactory stimuli (ligands). Olfactory receptors are the initial player in the signal transduction cascade producing a nerve impulse, which is transmitted to the brain. The sensitivity to a particular ligand depends on the expression level of multiple proteins involved in the process of olfactory cognition: olfactory receptor proteins, proteins that participate in signal transduction cascade, etc. The expression level of each gene is controlled by its regulatory regions, and especially, by the promoter [a region of DNA about 100-1000 base pairs long located upstream of the transcription start site (TSS)]. We analyzed single nucleotide polymorphisms using human whole-genome data from the 1000 Genomes Project and revealed an extremely high level of single nucleotide polymorphisms in promoter regions of olfactory receptor genes and HLA genes. We hypothesized that the high level of polymorphisms in olfactory receptor promoters was responsible for the diversity in regulatory mechanisms controlling the expression levels of olfactory receptor proteins. Such diversity of regulatory mechanisms may cause the great variability of olfactory cognition of numerous environmental olfactory stimuli perceived by human beings (air pollutants, human body odors, odors in culinary etc.). In turn, this variability may provide a wide range of emotional and behavioral reactions related to the vast variety of olfactory stimuli.

  6. A Bacterial Receptor PcrK Senses the Plant Hormone Cytokinin to Promote Adaptation to Oxidative Stress

    Directory of Open Access Journals (Sweden)

    Fang-Fang Wang

    2017-12-01

    Full Text Available Summary: Recognition of the host plant is a prerequisite for infection by pathogenic bacteria. However, how bacterial cells sense plant-derived stimuli, especially chemicals that function in regulating plant development, remains completely unknown. Here, we have identified a membrane-bound histidine kinase of the phytopathogenic bacterium Xanthomonas campestris, PcrK, as a bacterial receptor that specifically detects the plant cytokinin 2-isopentenyladenine (2iP. 2iP binds to the extracytoplasmic region of PcrK to decrease its autokinase activity. Through a four-step phosphorelay, 2iP stimulation decreased the phosphorylation level of PcrR, the cognate response regulator of PcrK, to activate the phosphodiesterase activity of PcrR in degrading the second messenger 3′,5′-cyclic diguanylic acid. 2iP perception by the PcrK-PcrR remarkably improves bacterial tolerance to oxidative stress by regulating the transcription of 56 genes, including the virulence-associated TonB-dependent receptor gene ctrA. Our results reveal an evolutionarily conserved, inter-kingdom signaling by which phytopathogenic bacteria intercept a plant hormone signal to promote adaptation to oxidative stress. : How pathogenic bacteria use receptors to recognize the signals of the host plant is unknown. Wang et al. have identified a bacterial receptor histidine kinase that specifically senses the plant hormone cytokinin. Through a four-step phosphorelay, cytokinin perception triggers degradation of a second messenger, c-di-GMP, to activate the bacterial response to oxidative stress. Keywords: histidine kinase, ligand, cytokinin, autokinase activity, phosphorelay, response regulator, two-component signal transduction system, Xanthomonas campestris pv. campestris, virulence, oxidative stress

  7. Deletion of G-protein-coupled receptor 55 promotes obesity by reducing physical activity.

    Science.gov (United States)

    Meadows, A; Lee, J H; Wu, C-S; Wei, Q; Pradhan, G; Yafi, M; Lu, H-C; Sun, Y

    2016-03-01

    Cannabinoid receptor 1 (CB1) is the best-characterized cannabinoid receptor, and CB1 antagonists are used in clinical trials to treat obesity. Because of the wide range of CB1 functions, the side effects of CB1 antagonists pose serious concerns. G-protein-coupled receptor 55 (GPR55) is an atypical cannabinoid receptor, and its pharmacology and functions are distinct from CB1. GPR55 regulates neuropathic pain, gut, bone, immune functions and motor coordination. GPR55 is expressed in various brain regions and peripheral tissues. However, the roles of GPR55 in energy and glucose homeostasis are unknown. Here we have investigated the roles of GPR55 in energy balance and insulin sensitivity using GPR55-null mice (GPR55(-/-)). Body composition of the mice was measured by EchoMRI. Food intake, feeding behavior, energy expenditure and physical activity of GPR55(-/-) mice were determined by indirect calorimetry. Muscle function was assessed by forced treadmill running test. Insulin sensitivity was evaluated by glucose and insulin tolerance tests. Adipose inflammation was assessed by flow cytometry analysis of adipose tissue macrophages. The expression of inflammatory markers in adipose tissues and orexigenic/anorexigenic peptides in the hypothalamus was also analyzed by real-time PCR. GPR55(-/-) mice had normal total energy intake and feeding pattern (i.e., no changes in meal size, meal number or feeding frequency). Intriguingly, whereas adult GPR55(-/-) mice only showed a modest increase in overall body weight, they exhibited significantly increased fat mass and insulin resistance. The spontaneous locomotor activity of GPR55(-/-) mice was dramatically decreased, whereas resting metabolic rate and non-shivering thermogenesis were unchanged. Moreover, GPR55(-/-) mice exhibited significantly decreased voluntary physical activity, showing reduced running distance on the running wheels, whereas muscle function appeared to be normal. GPR55 has an important role in energy

  8. Hematopoietic androgen receptor deficiency promotes visceral fat deposition in male mice without impairing glucose homeostasis

    OpenAIRE

    Rubinow, K. B.; Wang, S.; den Hartigh, L. J.; Subramanian, S.; Morton, G. J.; Buaas, F. W.; Lamont, D.; Gray, N.; Braun, R. E.; Page, S. T.

    2015-01-01

    Androgen deficiency in men increases body fat, but the mechanisms by which testosterone suppresses fat deposition have not been elucidated fully. Adipose tissue macrophages express the androgen receptor (AR) and regulate adipose tissue remodeling. Thus, testosterone signaling in macrophages could alter the paracrine function of these cells and thereby contribute to the metabolic effects of androgens in men. A metabolic phenotyping study was performed to determine whether the loss of AR signal...

  9. Activation of Olfactory Receptors on Mouse Pulmonary Macrophages Promotes Monocyte Chemotactic Protein-1 Production

    OpenAIRE

    Li, Jing Jing; Tay, Hock L.; Plank, Maximilian; Essilfie, Ama-Tawiah; Hansbro, Philip M.; Foster, Paul S.; Yang, Ming

    2013-01-01

    BACKGROUND: Emerging evidence suggests that non-olfactory tissues and cells can express olfactory receptors (ORs), however, the exact function of ectopic OR expression remains unknown. We have previously shown in mouse models that a unique cooperation between interferon-γ (IFN-γ) and lipopolysaccharide (LPS) drives the activation of pulmonary macrophages and leads to the induction of pathogenic responses in the respiratory tract. Further, through gene array studies, we have shown that activat...

  10. Perivascular Adipose Tissue Angiotensin II Type 1 Receptor Promotes Vascular Inflammation and Aneurysm Formation.

    Science.gov (United States)

    Sakaue, Tomoki; Suzuki, Jun; Hamaguchi, Mika; Suehiro, Chika; Tanino, Akiko; Nagao, Tomoaki; Uetani, Teruyoshi; Aono, Jun; Nakaoka, Hirotomo; Kurata, Mie; Sakaue, Tomohisa; Okura, Takafumi; Yasugi, Takumi; Izutani, Hironori; Higaki, Jitsuo; Ikeda, Shuntaro

    2017-10-01

    Perivascular adipose tissue exhibits characteristics of active local inflammation, which contributes to the development of atherosclerotic disease as a complication of obesity/metabolic syndrome. However, the precise role of perivascular adipose tissue in the progression of abdominal aortic aneurysm remains unclear. To test the hypothesis that genetic deletion of angiotensin II type 1a (AT 1a ) receptor in perivascular visceral adipose tissue (VAT) can attenuate aortic aneurysm formation in apolipoprotein E-deficient (ApoE -/- ) mice, we performed adipose tissue transplantation experiments by using an angiotensin II-induced aneurysm murine model, in which we transplanted VAT from ApoE -/- or ApoE -/- AT 1a -/- donor mice onto the abdominal aorta of ApoE -/- recipient mice. Compared with ApoE -/- VAT transplantation, ApoE -/- AT 1a -/- VAT transplantation markedly attenuated aortic aneurysm formation, macrophage infiltration, and gelatinolytic activity in the abdominal aorta. AT 1a receptor activation led to the polarization of macrophages in perivascular VAT toward the proinflammatory phenotype. Moreover, osteopontin expression and gelatinolytic activity were considerably lower in ApoE -/- AT 1a -/- perivascular VAT than in ApoE -/- perivascular VAT, and angiotensin II-induced osteopontin secretion from adipocytes was eliminated after deletion of AT 1a receptor in adipocytes. Notably, induction of macrophage migration by conditioned medium from angiotensin II-stimulated wild-type adipocytes was suppressed by treatment with an osteopontin-neutralizing antibody, and ApoE -/- OPN -/- VAT transplantation more potently attenuated aortic aneurysm formation than ApoE -/- VAT transplantation. Our findings indicate a previously unrecognized effect of AT 1a receptor in perivascular VAT on the pathogenesis of abdominal aortic aneurysm. © 2017 American Heart Association, Inc.

  11. TGF-α/HA complex promotes tympanic membrane keratinocyte migration and proliferation via ErbB1 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Mei Teh, Bing, E-mail: bing.teh@earscience.org.au [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Redmond, Sharon L. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Shen, Yi [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head and Neck, Ningbo Lihuili Hospital (Ningbo Medical Centre), Ningbo, Zhejiang (China); Atlas, Marcus D. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia); Department of Otolaryngology, Head, Neck and Skull Base Surgery, Sir Charles Gairdner Hospital, Nedlands, WA (Australia); Marano, Robert J.; Dilley, Rodney J. [Ear Sciences Centre, School of Surgery, The University of Western Australia, Nedlands, WA (Australia); Ear Science Institute Australia, Subiaco, WA (Australia)

    2013-04-01

    Tympanic membrane perforations are common and represent a management challenge to clinicians. Current treatments for chronic perforations involve a graft surgery and require general anaesthesia, including associated costs and morbidities. Bioactive molecules (e.g. growth factors, cytokines) play an important role in promoting TM wound healing following perforation and the use of growth factors as a topical treatment for tympanic membrane perforations has been suggested as an alternative to surgery. However, the choice of bioactive molecules best suited to promote wound healing has yet to be identified. We investigated the effects of hyaluronic acid, vitronectin, TGF-α, IL-24 and their combinations on migration, proliferation and adhesion of cultured human tympanic membrane-derived keratinocytes (hTM), in addition to their possible mechanisms of action. We found that TGF-α, TGF-α/HA and TGF-α/IL-24 promoted wound healing by significantly increasing both migration and proliferation. TGF-α and/or HA treated cells showed comparable cell–cell adhesion whilst maintaining an epithelial cell phenotype. With the use of receptor binding inhibitors for ErbB1 (AG1478) and CD44 (BRIC235), we revealed that the activation of ErbB1 is required for TGF-α/HA-mediated migration and proliferation. These results suggest factors that may be incorporated into a tissue-engineered membrane or directly as topical treatment for tympanic membrane perforations and hence reduce the need for a surgery. - Highlights: ► TGF-α, TGF-α/HA and TGF-α/IL-24 improved hTM keratinocyte migration and proliferation. ► TGF-α and/or HA maintained epithelial cell phenotype. ► TGF-α/HA-mediated migration and proliferation requires activation of ErbB1 receptor.

  12. Uncoupling the D1-N-methyl-D-aspartate (NMDA) receptor complex promotes NMDA-dependent long-term potentiation and working memory.

    Science.gov (United States)

    Nai, Qiang; Li, Shupeng; Wang, Szu-Han; Liu, Jing; Lee, Frank J S; Frankland, Paul W; Liu, Fang

    2010-02-01

    Although dopamine D1 receptors are involved in working memory, how D1 receptors contribute to this process remains unclear. Numerous studies have shown that D1 receptors have extensive functional interaction with N-methyl-D-aspartate (NMDA) receptor. Our group previously demonstrated that D1 receptors were able to regulate NMDA receptor functions through direct protein-protein interactions involving the carboxyl terminals of D1 receptors and NMDA receptor NR1a and NR2A subunits respectively. In this study, we explored the effects of the D1-NR1 interaction on NMDA receptor-dependent long-term potentiation (LTP) and working memory by using the TAT-conjugated interfering peptide (TAT-D1-t2). Miniature excitatory postsynaptic currents are recorded in rat hippocampal primary cultures. Coimmunoprecipitation and calcium/calmodulin-dependent protein kinase II (CaMKII) activity are measured in hippocampal slices and hippocampal neurons under the specified experimental conditions, respectively. Working memory was assessed using a delayed match-to-place protocol in the Morris Water Maze following administration of the TAT-D1-t2 peptide. Electrophysiology experiments showed that activation of D1 receptor upregulates NMDA receptor-mediated LTP in a CaMKII-dependent manner. Furthermore, D1 receptor agonist stimulation promotes the NR1-CaMKII coupling and enhances the CaMKII activity; and the D1 receptor-mediated effects can be blocked by the application of the TAT-D1-t2 peptide. Interestingly, animals injected with TAT-D1-t2 peptide exhibited significantly impaired working memory. Our study showed a critical role of NMDA-D1 direct protein-protein interaction in NMDA receptor-mediated LTP and working memory and implicated the involvement of CaMKII in this process. Copyright 2010 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.

  13. Membrane progesterone receptor beta (mPRβ/Paqr8) promotes progesterone-dependent neurite outgrowth in PC12 neuronal cells via non-G protein-coupled receptor (GPCR) signaling.

    Science.gov (United States)

    Kasubuchi, Mayu; Watanabe, Keita; Hirano, Kanako; Inoue, Daisuke; Li, Xuan; Terasawa, Kazuya; Konishi, Morichika; Itoh, Nobuyuki; Kimura, Ikuo

    2017-07-12

    Recently, sex steroid membrane receptors garnered world-wide attention because they may be related to sex hormone-mediated unknown rapid non-genomic action that cannot be currently explained by their genomic action via nuclear receptors. Progesterone affects cell proliferation and survival via non-genomic effects. In this process, membrane progesterone receptors (mPRα, mPRβ, mPRγ, mPRδ, and mPRε) were identified as putative G protein-coupled receptors (GPCRs) for progesterone. However, the structure, intracellular signaling, and physiological functions of these progesterone receptors are still unclear. Here, we identify a molecular mechanism by which progesterone promotes neurite outgrowth through mPRβ (Paqr8) activation. Mouse mPRβ mRNA was specifically expressed in the central nervous system. It has an incomplete GPCR topology, presenting 6 transmembrane domains and did not exhibit typical GPCR signaling. Progesterone-dependent neurite outgrowth was exhibited by the promotion of ERK phosphorylation via mPRβ, but not via other progesterone receptors such as progesterone membrane receptor 1 (PGRMC-1) and nuclear progesterone receptor in nerve growth factor-induced neuronal PC12 cells. These findings provide new insights of regarding the non-genomic action of progesterone in the central nervous system.

  14. alpha7 nicotinic receptor gene promoter polymorphisms in inbred mice affect expression in a cell type-specific fashion.

    Science.gov (United States)

    Mexal, Sharon; Jenkins, Paul M; Lautner, Meeghan A; Iacob, Eli; Crouch, Eric L; Stitzel, Jerry A

    2007-05-04

    Inbred mouse strains display significant differences in their levels of brain alpha7 nicotinic acetylcholine receptor (alpha7 nAChR) expression, as measured by binding of the alpha7-selective antagonist alpha-bungarotoxin. Variations in alpha-bungarotoxin binding have been shown to correlate with an animal's sensitivity to nicotine-induced seizures and sensory gating. In two inbred mouse strains, C3H/2Ibg (C3H) and DBA/2Ibg (DBA/2), the inter-strain binding differences are linked to a restriction length polymorphism in the alpha7 nAChR gene, Chrna7. Despite this finding, the molecular mechanism(s) through which genetic variability in Chrna7 may contribute to alpha7 nAChR expression differences remains unknown. However, studies of the human alpha7 nAChR gene (CHRNA7) previously have demonstrated that CHRNA7 promoter polymorphisms are associated with differences in promoter activity as well as differences in sensory processing. In the present study, a 947-base pair region of the Chrna7 promoter was cloned from both the C3H and DBA/2 inbred mouse strains in an attempt to identify polymorphisms that may underlie alpha7 nAChR differential expression. Sequence analysis of these fragments identified 14 single nucleotide polymorphisms (SNPs). A combination of two of these SNPs affects promoter activity in an in vitro luciferase reporter assay. These results suggest a mechanism through which the Chrna7 promoter genotype may influence interstrain variations in alpha7 nAChR expression.

  15. Microbial-Derived Butyrate Promotes Epithelial Barrier Function through IL-10 Receptor-Dependent Repression of Claudin-2.

    Science.gov (United States)

    Zheng, Leon; Kelly, Caleb J; Battista, Kayla D; Schaefer, Rachel; Lanis, Jordi M; Alexeev, Erica E; Wang, Ruth X; Onyiah, Joseph C; Kominsky, Douglas J; Colgan, Sean P

    2017-10-15

    Commensal interactions between the enteric microbiota and distal intestine play important roles in regulating human health. Short-chain fatty acids (SCFAs), such as butyrate, produced through anaerobic microbial metabolism represent a major energy source for the host colonic epithelium and enhance epithelial barrier function through unclear mechanisms. Separate studies revealed that the epithelial anti-inflammatory IL-10 receptor α subunit (IL-10RA) is also important for barrier formation. Based on these findings, we examined if SCFAs promote epithelial barrier through IL-10RA-dependent mechanisms. Using human intestinal epithelial cells (IECs), we discovered that SCFAs, particularly butyrate, enhanced IEC barrier formation, induced IL-10RA mRNA, IL-10RA protein, and transactivation through activated Stat3 and HDAC inhibition. Loss and gain of IL-10RA expression directly correlates with IEC barrier formation and butyrate represses permeability-promoting claudin-2 tight-junction protein expression through an IL-10RA-dependent mechanism. Our findings provide a novel mechanism by which microbial-derived butyrate promotes barrier through IL-10RA-dependent repression of claudin-2. Copyright © 2017 by The American Association of Immunologists, Inc.

  16. Proinflammatory tachykinins that signal through the neurokinin 1 receptor promote survival of dendritic cells and potent cellular immunity

    Science.gov (United States)

    Janelsins, Brian M.; Mathers, Alicia R.; Tkacheva, Olga A.; Erdos, Geza; Shufesky, William J.; Morelli, Adrian E.

    2009-01-01

    Dendritic cells (DCs) are the preferred targets for immunotherapy protocols focused on stimulation of cellular immune responses. However, regardless of initial promising results, ex vivo generated DCs do not always promote immune-stimulatory responses. The outcome of DC-dependent immunity is regulated by proinflammatory cytokines and neuropeptides. Proinflammatory neuropeptides of the tachykinin family, including substance P (SP) and hemokinin-1 (HK-1), bind the neurokinin 1 receptor (NK1R) and promote stimulatory immune responses. Nevertheless, the ability of pro-inflammatory tachykinins to affect the immune functions of DCs remains elusive. In the present work, we demonstrate that mouse bone marrow–derived DCs (BMDCs) generated in the presence of granulocyte macrophage–colony stimulating factor (GM-CSF) and interleukin-4 (IL-4), express functional NK1R. Signaling via NK1R with SP, HK-1, or the synthetic agonist [Sar9Met(O2)11]-SP rescues DCs from apoptosis induced by deprivation of GM-CSF and IL-4. Mechanistic analysis demonstrates that NK1R agonistic binding promotes DC survival via PI3K-Akt signaling cascade. In adoptive transfer experiments, NK1R-signaled BMDCs loaded with Ag exhibit increased longevity in draining lymph nodes, resulting in enhanced and prolonged effector cellular immunity. Our results contribute to the understanding of the interactions between the immune and nervous systems that control DC function and present a novel approach for ex vivo–generation of potent immune-stimulatory DCs. PMID:18987361

  17. G Protein-coupled Receptor Kinase 2 (GRK2 Promotes Breast Tumorigenesis Through a HDAC6-Pin1 Axis

    Directory of Open Access Journals (Sweden)

    Laura Nogués

    2016-11-01

    Full Text Available In addition to oncogenic drivers, signaling nodes can critically modulate cancer-related cellular networks to strength tumor hallmarks. We identify G-protein-coupled receptor kinase 2 (GRK2 as a relevant player in breast cancer. GRK2 is up-regulated in breast cancer cell lines, in spontaneous tumors in mice, and in a proportion of invasive ductal carcinoma patients. Increased GRK2 functionality promotes the phosphorylation and activation of the Histone Deacetylase 6 (HDAC6 leading to de-acetylation of the Prolyl Isomerase Pin1, a central modulator of tumor progression, thereby enhancing its stability and functional interaction with key mitotic regulators. Interestingly, a correlation between GRK2 expression and Pin1 levels and de-acetylation status is detected in breast cancer patients. Activation of the HDAC6-Pin1 axis underlies the positive effects of GRK2 on promoting growth factor signaling, cellular proliferation and anchorage-independent growth in both luminal and basal breast cancer cells. Enhanced GRK2 levels promote tumor growth in mice, whereas GRK2 down-modulation sensitizes cells to therapeutic drugs and abrogates tumor formation. Our data suggest that GRK2 acts as an important onco-modulator by strengthening the functionality of key players in breast tumorigenesis such as HDAC6 and Pin1.

  18. Promoted neuronal differentiation after activation of alpha4/beta2 nicotinic acetylcholine receptors in undifferentiated neural progenitors.

    Directory of Open Access Journals (Sweden)

    Takeshi Takarada

    Full Text Available BACKGROUND: Neural progenitor is a generic term used for undifferentiated cell populations of neural stem, neuronal progenitor and glial progenitor cells with abilities for proliferation and differentiation. We have shown functional expression of ionotropic N-methyl-D-aspartate (NMDA and gamma-aminobutyrate type-A receptors endowed to positively and negatively regulate subsequent neuronal differentiation in undifferentiated neural progenitors, respectively. In this study, we attempted to evaluate the possible functional expression of nicotinic acetylcholine receptor (nAChR by undifferentiated neural progenitors prepared from neocortex of embryonic rodent brains. METHODOLOGY/PRINCIPAL FINDINGS: Reverse transcription polymerase chain reaction analysis revealed mRNA expression of particular nAChR subunits in undifferentiated rat and mouse progenitors prepared before and after the culture with epidermal growth factor under floating conditions. Sustained exposure to nicotine significantly inhibited the formation of neurospheres composed of clustered proliferating cells and 3-[4,5-dimethylthiazol-2-yl]-2,5-diphenyltetrazolium bromide reduction activity at a concentration range of 1 µM to 1 mM without affecting cell survival. In these rodent progenitors previously exposed to nicotine, marked promotion was invariably seen for subsequent differentiation into cells immunoreactive for a neuronal marker protein following the culture of dispersed cells under adherent conditions. Both effects of nicotine were significantly prevented by the heteromeric α4β2 nAChR subtype antagonists dihydro-β-erythroidine and 4-(5-ethoxy-3-pyridinyl-N-methyl-(3E-3-buten-1-amine, but not by the homomeric α7 nAChR subtype antagonist methyllycaconitine, in murine progenitors. Sustained exposure to nicotine preferentially increased the expression of Math1 among different basic helix-loop-helix proneural genes examined. In undifferentiated progenitors from embryonic mice

  19. Histamine synergistically promotes bFGF-induced angiogenesis by enhancing VEGF production via H1 receptor.

    Science.gov (United States)

    Lu, Qian; Wang, Chong; Pan, Rong; Gao, Xinghua; Wei, Zhifeng; Xia, Yufeng; Dai, Yue

    2013-05-01

    Histamine, a major mediator present in mast cells that is released into the extracellular milieu upon degranulation, is well known to possess a wide range of biological activities in several classic physiological and pathological processes. However, whether and how it participates in angiogenesis remains obscure. In the present study, we observed its direct and synergistic action with basic fibroblast growth factor (bFGF), an important inducer of angiogenesis, on in vitro angiogenesis models of endothelial cells. Data showed that histamine (0.1, 1, 10 µM) itself was absent of direct effects on the processes of angiogenesis, including the proliferation, migration, and tube formation of endothelial cells. Nevertheless, it could concentration-dependently enhance bFGF-induced angiogenesis as well as production of vascular endothelial growth factor (VEGF) from endothelial cells. The synergistic effect of histamine on VEGF production could be reversed by pretreatments with diphenhydramine (H1-receptor antagonist), SB203580 (selective p38 mitogen-activated protein kinase (MAPK) inhibitor) and L-NAME (nitric oxide synthase (NOS) inhibitor), but not with cimetidine (H2-receptor antagonist) and indomethacin (cyclooxygenase (COX) inhibitor). Moreover, histamine could augment bFGF-incuced phosphorylation and degradation of IκBα, a key factor accounting for the activation and translocation of nuclear factor κB (NF-κB) in endothelial cells. These findings indicated that histamine was able to synergistically augment bFGF-induced angiogenesis, and this action was linked to VEGF production through H1-receptor and the activation of endothelial nitric oxide synthase (eNOS), p38 MAPK, and IκBα in endothelial cells. Copyright © 2012 Wiley Periodicals, Inc.

  20. P2Y6 Receptor Activation Promotes Inflammation and Tissue Remodeling in Pulmonary Fibrosis

    Directory of Open Access Journals (Sweden)

    Tobias Müller

    2017-08-01

    Full Text Available Idiopathic pulmonary fibrosis (IPF is a disease with a poor prognosis and very few available treatment options. The involvement of the purinergic receptor subtypes P2Y2 and P2X7 in fibrotic lung disease has been demonstrated recently. In this study, we investigated the role of P2Y6 receptors in the pathogenesis of IPF in humans and in the animal model of bleomycin-induced lung injury. P2Y6R expression was upregulated in lung structural cells but not in bronchoalveolar lavage (BAL cells derived from IPF patients as well as in animals following bleomycin administration. Furthermore, BAL fluid levels of the P2Y6R agonist uridine-5′-diphosphate were elevated in animals with bleomycin-induced pulmonary fibrosis. Inflammation and fibrosis following bleomycin administration were reduced in P2Y6R-deficient compared to wild-type animals confirming the pathophysiological relevance of P2Y6R subtypes for fibrotic lung diseases. Experiments with bone marrow chimeras revealed the importance of P2Y6R expression on lung structural cells for pulmonary inflammation and fibrosis. Similar effects were obtained when animals were treated with the P2Y6R antagonist MRS2578. In vitro studies demonstrated that proliferation and secretion of the pro-inflammatory/pro-fibrotic cytokine IL-6 by lung fibroblasts are P2Y6R-mediated processes. In summary, our results clearly demonstrate the involvement of P2Y6R subtypes in the pathogenesis of pulmonary fibrosis. Thus, blocking pulmonary P2Y6 receptors might be a new target for the treatment of IPF.

  1. Activation of the HSV-TK promoter in control reporter vector pBLCAT5 by liganded nuclear retinoid receptor RXRα

    Directory of Open Access Journals (Sweden)

    Nikčević Gordana

    2006-01-01

    Full Text Available Widely used reporter vector systems for studying the putative regulatory DNA elements usually contain basal promoters from pathogenic mammalian viruses. It is a common assumption that reliable results can be achieved only if the viral promoter activity is unaffected by transacting factors or any experimental treatment. Here we report that liganded nuclear retinoid receptor RXRa stimulates the HSV-TK promoter in control reporter vector pBLCAT5. Thus, TK driven reporter vectors should be employed only after thorough testing of the regulation of this promoter under experimental stimuli for a particular research purpose in order to avoid unreliable interpretation of the assay results.

  2. HMGB1 promotes neutrophil extracellular trap formation through interactions with Toll-like receptor 4

    Science.gov (United States)

    Tadie, Jean-Marc; Bae, Hong-Beom; Jiang, Shaoning; Park, Dae Won; Bell, Celeste P.; Yang, Huan; Pittet, Jean-Francois; Tracey, Kevin; Thannickal, Victor J.; Abraham, Edward

    2013-01-01

    Although neutrophil extracellular traps (NETs) form to prevent dissemination of pathogenic microorganisms, excessive release of DNA and DNA-associated proteins can also perpetuate sterile inflammation. In this study, we found that the danger-associated molecular pattern protein high-mobility group box 1 (HMGB1) can induce NET formation. NET formation was found after exposure of wild-type and receptor for advanced glycation end products-deficient neutrophil to HMGB1, whereas deficiency of Toll-like receptor (TLR)4 diminished the ability of neutrophils to produce NETs. Incubation of neutrophils with HMGB1 significantly increased the amount of DNA and histone 3 released as well as intracellular histone 3 citrullination, a signaling event that precedes chromatin decondensation. In vivo, neutrophils isolated from bronchoalveolar lavages of mice exposed to LPS and HMGB1 showed consistently greater ability to produce NETs compared with pulmonary neutrophils from mice that received LPS alone. In contrast, mice treated with LPS and neutralizing antibody to HMGB1 had decreased amounts of the inflammatory cytokines TNF-α and macrophage inflammatory protein 2, as well as of free DNA and histone 3 in bronchoalveolar lavage fluids. Airway neutrophils from LPS-exposed mice that had been treated with anti-HMGB1 antibodies showed decreased citrullination of histone 3. These results demonstrate that interactions between HMGB1 and TLR4 enhance the formation of NETs and provide a novel mechanism through which HMGB1 may contribute to the severity of neutrophil-associated inflammatory conditions. PMID:23316068

  3. Toll-Like Receptor 9 Promotes Cardiac Inflammation and Heart Failure during Polymicrobial Sepsis

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    Ralph Lohner

    2013-01-01

    Full Text Available Background. Aim was to elucidate the role of toll-like receptor 9 (TLR9 in cardiac inflammation and septic heart failure in a murine model of polymicrobial sepsis. Methods. Sepsis was induced via colon ascendens stent peritonitis (CASP in C57BL/6 wild-type (WT and TLR9-deficient (TLR9-D mice. Bacterial load in the peritoneal cavity and cardiac expression of inflammatory mediators were determined at 6, 12, 18, 24, and 36 h. Eighteen hours after CASP cardiac function was monitored in vivo. Sarcomere length of isolated cardiomyocytes was measured at 0.5 to 10 Hz after incubation with heat-inactivated bacteria. Results. CASP led to continuous release of bacteria into the peritoneal cavity, an increase of cytokines, and differential regulation of receptors of innate immunity in the heart. Eighteen hours after CASP WT mice developed septic heart failure characterised by reduction of end-systolic pressure, stroke volume, cardiac output, and parameters of contractility. This coincided with reduced cardiomyocyte sarcomere shortening. TLR9 deficiency resulted in significant reduction of cardiac inflammation and a sustained heart function. This was consistent with reduced mortality in TLR9-D compared to WT mice. Conclusions. In polymicrobial sepsis TLR9 signalling is pivotal to cardiac inflammation and septic heart failure.

  4. Endogenous activation of adenosine A1 receptors promotes post-ischemic electrocortical burst suppression

    DEFF Research Database (Denmark)

    Ilie, A; Ciocan, D; Constantinescu, A O

    2009-01-01

    and 5-min GCI and bi-exponential after 10-min GCI. The BS recovery was progressively delayed with the duration of ischemia. Administration of the A1R antagonist 1,3-dipropyl-8-cyclopentylxanthine (DPCPX, 1.25 mg/kg i.p.) accelerated the post-ischemic BS recovery for all GCI durations. Following the 10......-min GCI the effect of DPCPX was only apparent on the initial fast decay of the BS ratio. These data suggest that endogenous adenosine release promotes BS patterns during reperfusion following transient cerebral ischemia. Furthermore, the endogenous A1R activation may be the primary underlying cause...... of post-ischemic BS patterns following brief ischemic episodes. It is likely that synaptic depression by post-ischemic A1R activation functionally disrupts the connectivity within the cortical networks to an extent that promotes BS patterns....

  5. Nucleus Accumbens Shell and mPFC but not Insula Orexin-1 Receptors Promote Excessive Alcohol Drinking

    Directory of Open Access Journals (Sweden)

    Kelly Lei

    2016-08-01

    Full Text Available Addiction to alcohol remains a major social and economic problem, in part because of the high motivation for alcohol that humans exhibit and the hazardous binge intake this promotes. Orexin-1-type receptors (OX1Rs promote reward intake under conditions of strong drives for reward, including excessive alcohol intake. While systemic modulation of OX1Rs can alter alcohol drinking, the brain regions that mediate this OX1R enhancement of excessive drinking remain unknown. Given the importance of the nucleus accumbens (NAc and anterior insular cortex (aINS in driving many addictive behaviors, including OX1Rs within these regions, we examined the importance of OX1Rs in these regions on excessive alcohol drinking in C57BL/6 mice during limited-access alcohol drinking in the dark cycle. Inhibition of OX1Rs with the widely used SB-334867 within the medial NAc Shell (mNAsh significantly reduced drinking of alcohol, with no effect on saccharin intake, and no effect on alcohol consumption when infused above the mNAsh. In contrast, intra-mNAsh infusion of the orexin-2 receptor TCS-OX2-29 had no impact on alcohol drinking. In addition, OX1R inhibition within the aINS had no effect on excessive drinking, which was surprising given the importance of aINS-NAc circuits in promoting alcohol consumption and the role for aINS OX1Rs in driving nicotine intake. However, OX1R inhibition within the mPFC did reduce alcohol drinking, indicating cortical OXR involvement in promoting intake. Also, in support of the critical role for mNAsh OX1Rs, SB within the mNAsh also significantly reduced operant alcohol self-administration in rats. Finally, orexin ex vivo enhanced firing in mNAsh neurons from alcohol-drinking mice, with no effect on evoked EPSCs or input resistance; a similar orexin increase in firing without a change in input resistance was observed in alcohol-naïve mice. Taken together, our results strongly suggest that OX1Rs within the mNAsh, but not the aINS, play a

  6. Nucleus Accumbens Shell and mPFC but Not Insula Orexin-1 Receptors Promote Excessive Alcohol Drinking.

    Science.gov (United States)

    Lei, Kelly; Wegner, Scott A; Yu, Ji Hwan; Mototake, Arisa; Hu, Bing; Hopf, Frederic W

    2016-01-01

    Addiction to alcohol remains a major social and economic problem, in part because of the high motivation for alcohol that humans exhibit and the hazardous binge intake this promotes. Orexin-1-type receptors (OX1Rs) promote reward intake under conditions of strong drives for reward, including excessive alcohol intake. While systemic modulation of OX1Rs can alter alcohol drinking, the brain regions that mediate this OX1R enhancement of excessive drinking remain unknown. Given the importance of the nucleus accumbens (NAc) and anterior insular cortex (aINS) in driving many addictive behaviors, including OX1Rs within these regions, we examined the importance of OX1Rs in these regions on excessive alcohol drinking in C57BL/6 mice during limited-access alcohol drinking in the dark cycle. Inhibition of OX1Rs with the widely used SB-334867 within the medial NAc Shell (mNAsh) significantly reduced drinking of alcohol, with no effect on saccharin intake, and no effect on alcohol consumption when infused above the mNAsh. In contrast, intra-mNAsh infusion of the orexin-2 receptor TCS-OX2-29 had no impact on alcohol drinking. In addition, OX1R inhibition within the aINS had no effect on excessive drinking, which was surprising given the importance of aINS-NAc circuits in promoting alcohol consumption and the role for aINS OX1Rs in driving nicotine intake. However, OX1R inhibition within the mPFC did reduce alcohol drinking, indicating cortical OXR involvement in promoting intake. Also, in support of the critical role for mNAsh OX1Rs, SB within the mNAsh also significantly reduced operant alcohol self-administration in rats. Finally, orexin ex vivo enhanced firing in mNAsh neurons from alcohol-drinking mice, with no effect on evoked EPSCs or input resistance; a similar orexin increase in firing without a change in input resistance was observed in alcohol-naïve mice. Taken together, our results suggest that OX1Rs within the mNAsh and mPFC, but not the aINS, play a central role in

  7. Statin-activated nuclear receptor PXR promotes SGK2 dephosphorylation by scaffolding PP2C to induce hepatic gluconeogenesis.

    Science.gov (United States)

    Gotoh, Saki; Negishi, Masahiko

    2015-09-22

    Statin therapy is known to increase blood glucose levels in humans. Statins utilize pregnane X receptor (PXR) and serum/glucocorticoid regulated kinase 2 (SGK2) to activate phosphoenolpyruvate carboxykinase 1 (PEPCK1) and glucose-6-phosphatase (G6Pase) genes, thereby increasing glucose production in human liver cells. Here, the novel statin/PXR/SGK2-mediated signaling pathway has now been characterized for hepatic gluconeogenesis. Statin-activated PXR scaffolds the protein phosphatase 2C (PP2C) and SGK2 to stimulate PP2C to dephosphorylate SGK2 at threonine 193. Non-phosphorylated SGK2 co-activates PXR-mediated trans-activation of promoters of gluconeogenic genes in human liver cells, thereby enhancing gluconeogenesis. This gluconeogenic statin-PXR-SGK2 signal is not present in mice, in which statin treatment suppresses hepatic gluconeogenesis. These findings provide the basis for statin-associated side effects such as an increased risk for Type 2 diabetes.

  8. Prostate-specific G-protein-coupled receptor collaborates with loss of PTEN to promote prostate cancer progression.

    Science.gov (United States)

    Rodriguez, M; Siwko, S; Zeng, L; Li, J; Yi, Z; Liu, M

    2016-03-03

    Among frequent events in prostate cancer are loss of the tumor-suppressor phosphatase and tensin homologue (PTEN) and overexpression of prostate-specific G-protein-coupled receptor (PSGR), but the potential tumorigenic synergy between these lesions is unknown. Here, we report a new mouse model (PSGR-Pten(Δ/Δ)) combining prostate-specific loss of Pten with probasin promoter-driven PSGR overexpression. By 12 months PSGR-Pten(Δ/Δ) mice developed invasive prostate tumors featuring Akt activation and extensive inflammatory cell infiltration. PSGR-Pten(Δ/Δ) tumors exhibited E-cadherin loss and increased stromal androgen receptor (AR) expression. PSGR overexpression increased LNCaP proliferation, whereas PSGR short hairpin RNA knockdown inhibited proliferation and migration. In conclusion, we demonstrate that PSGR overexpression synergizes with loss of PTEN to accelerate prostate cancer development, and present a novel bigenic mouse model that mimics the human condition, where both PSGR overexpression and loss of PTEN occur concordantly in the majority of advanced prostate cancers, yielding an environment more relevant to studying human prostate cancer.

  9. Deletion of Macrophage Vitamin D Receptor Promotes Insulin Resistance and Monocyte Cholesterol Transport to Accelerate Atherosclerosis in Mice

    Directory of Open Access Journals (Sweden)

    Jisu Oh

    2015-03-01

    Full Text Available Intense effort has been devoted to understanding predisposition to chronic systemic inflammation because it contributes to cardiometabolic disease. We demonstrate that deletion of the macrophage vitamin D receptor (VDR in mice (KODMAC is sufficient to induce insulin resistance by promoting M2 macrophage accumulation in the liver as well as increasing cytokine secretion and hepatic glucose production. Moreover, VDR deletion increases atherosclerosis by enabling lipid-laden M2 monocytes to adhere, migrate, and carry cholesterol into the atherosclerotic plaque and by increasing macrophage cholesterol uptake and esterification. Increased foam cell formation results from lack of VDR-SERCA2b interaction, causing SERCA dysfunction, activation of ER stress-CaMKII-JNKp-PPARγ signaling, and induction of the scavenger receptors CD36 and SR-A1. Bone marrow transplant of VDR-expressing cells into KODMAC mice improved insulin sensitivity, suppressed atherosclerosis, and decreased foam cell formation. The immunomodulatory effects of vitamin D in macrophages are thus critical in diet-induced insulin resistance and atherosclerosis in mice.

  10. Engagement of Platelet Toll-Like Receptor 9 by Novel Endogenous Ligands Promotes Platelet Hyper-Reactivity and Thrombosis

    Science.gov (United States)

    Panigrahi, Soumya; Ma, Yi; Hong, Li; Gao, Detao; West, Xiaoxia Z.; Salomon, Robert G.; Byzova, Tatiana V.; Podrez, Eugene A.

    2012-01-01

    Rationale A prothrombotic state and increased platelet reactivity are common in pathophysiological conditions associated with oxidative stress and infections. Such conditions are associated with an appearance of altered-self ligands in circulation that can be recognized by Toll-like receptors (TLR). Platelets express a number of TLR, including TLR9, however, the role of TLR in platelet function and thrombosis is poorly understood. Objective To investigate the biological activities of carboxy(alkylpyrrole) protein adducts (CAPs), an altered self-ligand generated in oxidative stress, on platelet function and thrombosis. Methods and Results In this study we show that CAPs represent novel unconventional ligands for TLR9. Furthermore, using human and murine platelets, we demonstrate that CAPs promote platelet activation, granule secretion, and aggregation in vitro and thrombosis in vivo via the TLR9/MyD88 pathway. Platelet activation by TLR9 ligands induces IRAK1 and AKT phosphorylation, and is Src kinase dependent. Physiological platelet agonists act synergistically with TLR9 ligands by inducing TLR9 expression on the platelet surface. Conclusions Our study demonstrates that platelet TLR9 is a functional platelet receptor that links oxidative stress, innate immunity, and thrombosis. PMID:23071157

  11. Calcium Promotes Human Gastric Cancer via a Novel Coupling of Calcium-Sensing Receptor and TRPV4 Channel.

    Science.gov (United States)

    Xie, Rui; Xu, Jingyu; Xiao, Yufeng; Wu, Jilin; Wan, Hanxing; Tang, Bo; Liu, Jingjing; Fan, Yahan; Wang, Suming; Wu, Yuyun; Dong, Tobias Xiao; Zhu, Michael X; Carethers, John M; Dong, Hui; Yang, Shiming

    2017-12-01

    Although dietary calcium intake has long been recommended for disease prevention, the influence of calcium in development of cancer in the upper gastrointestinal tract has not been explored. Here, we assess the roles of calcium and calcium-sensing receptor (CaSR) in gastric cancer development. CaSR expression was enhanced in gastric cancer specimens, which positively correlated with serum calcium concentrations, tumor progression, poor survival, and male gender in gastric cancer patients. CaSR and transient receptor potential cation channel subfamily V member 4 (TRPV4) were colocalized in gastric cancer cells, and CaSR activation evoked TRPV4-mediated Ca 2+ entry. Both CaSR and TRPV4 were involved in Ca 2+ -induced proliferation, migration, and invasion of gastric cancer cells through a Ca 2+ /AKT/β-catenin relay, which occurred only in gastric cancer cells or normal cells overexpressing CaSR. Tumor growth and metastasis of gastric cancer depended on CaSR in nude mice. Overall, our findings indicate that calcium may enhance expression and function of CaSR to potentially promote gastric cancer, and that targeting the novel CaSR/TRPV4/Ca 2+ pathway might serve as preventive or therapeutic strategies for gastric cancer. Cancer Res; 77(23); 6499-512. ©2017 AACR . ©2017 American Association for Cancer Research.

  12. The G-protein coupled chemoattractant receptor FPR2 promotes malignant phenotype of human colon cancer cells

    Science.gov (United States)

    Xiang, Yi; Yao, Xiaohong; Chen, Keqiang; Wang, Xiafei; Zhou, Jiamin; Gong, Wanghua; Yoshimura, Teizo; Huang, Jiaqiang; Wang, Rongquan; Wu, Yuzhang; Shi, Guochao; Bian, Xiuwu; Wang, Jiming

    2016-01-01

    The G-protein coupled chemoattractant receptor formylpeptide receptor-2 (FPR2 in human, Fpr2 in mice) is expressed by mouse colon epithelial cells and plays a critical role in mediating mucosal homeostasis and inflammatory responses. However, the biological role of FPR2 in human colon is unclear. Our investigation revealed that a considerable number of human colon cancer cell lines expressed FPR2 and its ligands promoted cell migration and proliferation. Human colon cancer cell lines expressing high levels of FPR2 also formed more rapidly growing tumors in immunocompromised mice as compared with cell lines expressing lower levels of FPR2. Knocking down of FPR2 from colon cancer cell lines highly expressing FPR2 reduced their tumorigenicity. Clinically, FPR2 is more highly expressed in progressive colon cancer, associated with poorer patient prognosis. These results suggest that FPR2 can be high-jacked by colon cancer cells for their growth advantage, thus becoming a potential target for therapeutic development. PMID:27904774

  13. Elevated chemokine CC-motif receptor-like 2 (CCRL2) promotes cell migration and invasion in glioblastoma.

    Science.gov (United States)

    Yin, Fengqiong; Xu, Zhenhua; Wang, Zifeng; Yao, Hong; Shen, Zan; Yu, Fang; Tang, Yiping; Fu, Dengli; Lin, Sheng; Lu, Gang; Kung, Hsiang-Fu; Poon, Wai Sang; Huang, Yunchao; Lin, Marie Chia-Mi

    2012-12-14

    Chemokine CC-motif receptor-like 2 (CCRL2) is a 7-transmembrane G protein-coupled receptor which plays a key role in lung dendritic cell trafficking to peripheral lymph nodes. The function and expression of CCRL2 in cancer is not understood at present. Here we report that CCRL2 expression level is elevated in human glioma patient samples and cell lines. The magnitude of increase is positively associated with increasing tumor grade, with the highest level observed in grade IV glioblastoma. By gain-of-function and loss-of-function studies, we further showed that CCRL2 did not regulate the growth of human glioblatoma U87 and U373 cells. Importantly, we demonstrated that over-expression of CCRL2 significantly enhanced the migration rate and invasiveness of the glioblastoma cells. Taken together, these results suggest for the first time that elevated CCRL2 in glioma promotes cell migration and invasion. The potential roles of CCRL2 as a novel therapeutic target and biomarker warrant further investigations. Copyright © 2012 Elsevier Inc. All rights reserved.

  14. Hypoxia and prostaglandin E receptor 4 signalling pathways synergise to promote endometrial adenocarcinoma cell proliferation and tumour growth.

    Science.gov (United States)

    Catalano, Rob D; Wilson, Martin R; Boddy, Sheila C; McKinlay, Andrew T M; Sales, Kurt J; Jabbour, Henry N

    2011-05-12

    The prostaglandin endoperoxide synthase (PTGS) pathway is a potent driver of tumour development in humans by enhancing the biosynthesis and signalling of prostaglandin (PG) E(2). PTGS2 expression and PGE(2) biosynthesis is elevated in endometrial adenocarcinoma, however the mechanism whereby PTGS and PGE(2) regulate endometrial tumour growth is unknown. Here we investigated (a) the expression profile of the PGE synthase enzymes (PTGES, PTGES-2, PTGES-3) and PGE receptors (PTGER1-4) in endometrial adenocarcinomas compared with normal endometrium and (b) the role of PTGER4 in endometrial tumorigenesis in vivo. We found elevated expression of PTGES2 and PTGER4 and suppression of PTGER1 and PTGER3 in endometrial adenocarcinomas compared with normal endometrium. Using WT Ishikawa endometrial adenocarcinoma cells and Ishikawa cells stably transfected with the full length PTGER4 cDNA (PTGER4 cells) xenografted in the dorsal flanks of nude mice, we show that PTGER4 rapidly and significantly enhances tumour growth rate. Coincident with enhanced PTGER4-mediated tumour growth we found elevated expression of PTGS2 in PTGER4 xenografts compared with WT xenografts. Furthermore we found that the augmented growth rate of the PTGER4 xenografts was not due to enhanced angiogenesis, but regulated by an increased proliferation index and hypoxia. In vitro, we found that PGE(2) and hypoxia independently induce expression of PTGER4 indicating two independent pathways regulating prostanoid receptor expression. Finally we have shown that PGE(2) and hypoxia synergise to promote cellular proliferation of endometrial adenocarcinoma cells.

  15. Angiotensin II promotes development of the renal microcirculation through AT1 receptors

    DEFF Research Database (Denmark)

    Madsen, Kirsten; Marcussen, Niels; Pedersen, Michael

    2010-01-01

    Pharmacologic or genetic deletion of components of the renin-angiotensin system leads to postnatal kidney injury, but the roles of these components in kidney development are unknown. To test the hypothesis that angiotensin II supports angiogenesis during postnatal kidney development, we quantified...... CD31(+) postglomerular microvessels, performed quantitative PCR analysis of vascular growth factor expression, and measured renal blood flow by magnetic resonance. Treating rats with the angiotensin II type 1 receptor antagonist candesartan for 2 weeks after birth reduced the total length, volume......, and surface area of capillaries in both the cortex and the medulla and inhibited the organization of vasa recta bundles. In addition, angiotensin II type 1 antagonism inhibited the transcription of angiogenic growth factors vascular endothelial growth factor, angiopoietin-1, angiopoietin-2...

  16. Aldosterone-mineralocorticoid receptor promotes urine prostasin through glomerular barrier injury and not tissue abundance

    DEFF Research Database (Denmark)

    Stolzenburg Oxlund, Christina; Kurt, B.; Schwarzensteiner, I.

    2015-01-01

    Objective: Low salt intake or infusion with the mineralocorticoid hormone aldosterone increases the abundance of proteolytically activated gamma ENaC in rat kidney. Prostasin is a serine proteinase GPI-anchored to the apical membrane of renal principal cells. It was hypothesized that the aldoster......Objective: Low salt intake or infusion with the mineralocorticoid hormone aldosterone increases the abundance of proteolytically activated gamma ENaC in rat kidney. Prostasin is a serine proteinase GPI-anchored to the apical membrane of renal principal cells. It was hypothesized...... that the aldosterone- mineralocorticoid receptor (MR) pathway maintains prostasin abundance in human kidney. Design and method: Urine and plasma prostasin was measured by ELISA in urine and plasma from a cohort of type-2 diabetes patients (n = 112) with treatment resistant hypertension before and after intervention...

  17. Acetylcholine promotes binding of α-conotoxin MII at α3 β2 nicotinic acetylcholine receptors.

    Science.gov (United States)

    Sambasivarao, Somisetti V; Roberts, Jessica; Bharadwaj, Vivek S; Slingsby, Jason G; Rohleder, Conrad; Mallory, Chris; Groome, James R; McDougal, Owen M; Maupin, C Mark

    2014-02-10

    α-Conotoxin MII (α-CTxMII) is a 16-residue peptide with the sequence GCCSNPVCHLEHSNLC, containing Cys2-Cys8 and Cys3-Cys16 disulfide bonds. This peptide, isolated from the venom of the marine cone snail Conus magus, is a potent and selective antagonist of neuronal nicotinic acetylcholine receptors (nAChRs). To evaluate the impact of channel-ligand interactions on ligand-binding affinity, homology models of the heteropentameric α3β2-nAChR were constructed. The models were created in MODELLER with the aid of experimentally characterized structures of the Torpedo marmorata-nAChR (Tm-nAChR, PDB ID: 2BG9) and the Aplysia californica-acetylcholine binding protein (Ac-AChBP, PDB ID: 2BR8) as templates for the α3- and β2-subunit isoforms derived from rat neuronal nAChR primary amino acid sequences. Molecular docking calculations were performed with AutoDock to evaluate interactions of the heteropentameric nAChR homology models with the ligands acetylcholine (ACh) and α-CTxMII. The nAChR homology models described here bind ACh with binding energies commensurate with those of previously reported systems, and identify critical interactions that facilitate both ACh and α-CTxMII ligand binding. The docking calculations revealed an increased binding affinity of the α3β2-nAChR for α-CTxMII with ACh bound to the receptor, and this was confirmed through two-electrode voltage clamp experiments on oocytes from Xenopus laevis. These findings provide insights into the inhibition and mechanism of electrostatically driven antagonist properties of the α-CTxMIIs on nAChRs. Copyright © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Cysteine dioxygenase type 1 promotes adipogenesis via interaction with peroxisome proliferator-activated receptor gamma

    Energy Technology Data Exchange (ETDEWEB)

    Deng, Peng; Chen, Yi; Ji, Ning; Lin, Yunfeng; Yuan, Quan; Ye, Ling; Chen, Qianming, E-mail: qmchen@scu.edu.cn

    2015-02-27

    Mammalian cysteine dioxygenase type 1 (CDO1) is an essential enzyme for taurine biosynthesis and the biodegradation of toxic cysteine. As previously suggested, Cdo1 may be a marker of liposarcoma progression and adipogenic differentiation, but the role of Cdo1 in adipogenesis has yet been reported. In this study, we found that the expression of Cdo1 is dramatically elevated during adipogenic differentiation of 3T3-L1 pre-adipocytes and mouse bone marrow-derived mesenchymal stem cells (mBMSCs). Conversely, knockdown of Cdo1 inhibited expression of adipogenic specific genes and lipid droplet formation in 3T3-L1 cells and mBMSCs. Mechanistically, we found Cdo1 interacted with Pparγ in response to adipogenic stimulus. Further, depletion of Cdo1 reduced the recruitment of Pparγ to the promoters of C/EBPα and Fabp4. Collectively, our finding indicates that Cdo1 may be a co-activator of Pparγ in adipogenesis, and may contribute to the development of disease associated with excessive adipose tissue. - Highlights: • Cdo1expression is highly up-regulated during adipogenic differentiation of 3T3-L1 and mBMSCs. • Depletion of Cdo1 inhibited expression of adipogenic specific genes and lipid droplet formation. • Cdo1interacts with Pparγ during adipogenesis. • Knockdown of Cdo1 inhibited Pparγ binding to the promoters of C/EBPα and Fabp4.

  19. The ABA receptor PYL8 promotes lateral root growth by enhancing MYB77-dependent transcription of auxin-responsive genes.

    Science.gov (United States)

    Zhao, Yang; Xing, Lu; Wang, Xingang; Hou, Yueh-Ju; Gao, Jinghui; Wang, Pengcheng; Duan, Cheng-Guo; Zhu, Xiaohong; Zhu, Jian-Kang

    2014-06-03

    The phytohormone abscisic acid (ABA) regulates plant growth, development, and abiotic stress responses. ABA signaling is mediated by a group of receptors known as the PYR1/PYL/RCAR family, which includes the pyrabactin resistance 1-like protein PYL8. Under stress conditions, ABA signaling activates SnRK2 protein kinases to inhibit lateral root growth after emergence from the primary root. However, even in the case of persistent stress, lateral root growth eventually recovers from inhibition. We showed that PYL8 is required for the recovery of lateral root growth, following inhibition by ABA. PYL8 directly interacted with the transcription factors MYB77, MYB44, and MYB73. The interaction of PYL8 and MYB77 increased the binding of MYB77 to its target MBSI motif in the promoters of multiple auxin-responsive genes. Compared to wild-type seedlings, the lateral root growth of pyl8 mutant seedlings and myb77 mutant seedlings was more sensitive to inhibition by ABA. The recovery of lateral root growth was delayed in pyl8 mutant seedlings in the presence of ABA, and the defect was rescued by exposing pyl8 mutant seedlings to the auxin IAA (3-indoleacetic acid). Thus, PYL8 promotes lateral root growth independently of the core ABA-SnRK2 signaling pathway by enhancing the activities of MYB77 and its paralogs, MYB44 and MYB73, to augment auxin signaling. Copyright © 2014, American Association for the Advancement of Science.

  20. Expression of Toll-Like Receptor 2 in Glomerular Endothelial Cells and Promotion of Diabetic Nephropathy by Porphyromonas gingivalis Lipopolysaccharide

    Science.gov (United States)

    Hatakeyama, Yuji; Ishikawa, Hiroyuki; Tsuruga, Eichi

    2014-01-01

    The toll-like receptor (TLR) has been suggested as a candidate cause for diabetic nephropathy. Recently, we have reported the TLR4 expression in diabetic mouse glomerular endothelium. The study here investigates the effects of the periodontal pathogen Porphyromonas gingivalis lipopolysaccharide (LPS) which is a ligand for TLR2 and TLR4 in diabetic nephropathy. In laser-scanning microscopy of glomeruli of streptozotocin- and a high fat diet feed-induced type I and type II diabetic mice, TLR2 localized on the glomerular endothelium and proximal tubule epithelium. The TLR2 mRNA was detected in diabetic mouse glomeruli by in situ hybridization and in real-time PCR of the renal cortex, the TLR2 mRNA amounts were larger in diabetic mice than in non-diabetic mice. All diabetic mice subjected to repeated LPS administrations died within the survival period of all of the diabetic mice not administered LPS and of all of the non-diabetic LPS-administered mice. The LPS administration promoted the production of urinary protein, the accumulation of type I collagen in the glomeruli, and the increases in IL-6, TNF-α, and TGF-β in the renal cortex of the glomeruli of the diabetic mice. It is thought that blood TLR ligands like Porphyromonas gingivalis LPS induce the glomerular endothelium to produce cytokines which aid glomerulosclerosis. Periodontitis may promote diabetic nephropathy. PMID:24835775

  1. Histone acetylation characterizes chromatin presetting by NF1 and Oct1 and enhances glucocorticoid receptor binding to the MMTV promoter

    International Nuclear Information System (INIS)

    Astrand, Carolina; Belikov, Sergey; Wrange, Orjan

    2009-01-01

    Transcription from the mouse mammary tumor virus (MMTV) promoter is induced by the glucocorticoid receptor (GR). This switch was reconstituted in Xenopus oocytes. Previously, we showed that Nuclear Factor 1 (NF1) and Octamer Transcription Factor 1 (Oct1) bind constitutively to the MMTV promoter and thereby induce translational nucleosome positioning representing an intermediary, i.e. preset, state of nucleosome organization. Here we further characterize this NF1 and Oct1 induced preset chromatin in relation to the inactive and the hormone-activated state. The preset chromatin exhibits increased histone acetylation but does not cause dissociation of histone H1 as oppose to the hormone-activated state. Furthermore, upon hormone induction the preset MMTV chromatin displays an enhanced and prolonged GR binding capacity and transcription during an intrinsic and time-dependent silencing of the injected template. The silencing process correlates with a reduced histone acetylation. However, a histone deacetylase inhibitor, trichostatin A (TSA), does not counteract silencing in spite of its distinct stimulation of GR-DNA binding. The latter indicates the importance of histone acetylation to maintain DNA access for inducible factor binding. We discuss how constitutively bound factors such as NF1 and Oct1 may participate in the maintenance of tissue specificity of hormone responsive genes.

  2. Novel variants in the putative peroxisome proliferator-activated receptor {gamma} promoter and relationships with obesity in men

    DEFF Research Database (Denmark)

    Larsen, Thomas M; Larsen, Lesli H; Torekov, Signe K

    2005-01-01

    Yet unidentified variants within the peroxisome proliferator-activated receptor gamma (PPARgamma) 2 promoter may explain the inconsistent reports on associations between variants in the coding region and obesity or diabetes. Thus, we examined the putative PPARgamma2 promoter (-3371 to +43 bp......) for variants in 83 subjects with obesity or type 2 diabetes. We identified eight variants, seven of which were novel, including -792A>G, -816C>T, -882T>C, -1505G>A, -1881C>T, -1884T>A, -2604T>C, and -2953A>G. The variants -816C>T, -1505G>A, -1881C>T, and -2604T>C were in total linkage disequilibrium...... nonobese men with a BMI of 21.7+/-2.5 kg/m2, who were also reexamined after approximately 29 years. The prevalence of the identified variants was not significantly different between the two groups, and the variants did not affect changes in BMI over time. In conclusion, the identified novel variants...

  3. Histone acetylation characterizes chromatin presetting by NF1 and Oct1 and enhances glucocorticoid receptor binding to the MMTV promoter

    Energy Technology Data Exchange (ETDEWEB)

    Astrand, Carolina, E-mail: ca340@cam.ac.uk [Department of Cell and Molecular Biology, Karolinska Institutet, SE-171 77 Stockholm (Sweden); Belikov, Sergey, E-mail: Sergey.Belikov@ki.se [Department of Cell and Molecular Biology, Karolinska Institutet, SE-171 77 Stockholm (Sweden); Wrange, Orjan, E-mail: Orjan.Wrange@ki.se [Department of Cell and Molecular Biology, Karolinska Institutet, SE-171 77 Stockholm (Sweden)

    2009-09-10

    Transcription from the mouse mammary tumor virus (MMTV) promoter is induced by the glucocorticoid receptor (GR). This switch was reconstituted in Xenopus oocytes. Previously, we showed that Nuclear Factor 1 (NF1) and Octamer Transcription Factor 1 (Oct1) bind constitutively to the MMTV promoter and thereby induce translational nucleosome positioning representing an intermediary, i.e. preset, state of nucleosome organization. Here we further characterize this NF1 and Oct1 induced preset chromatin in relation to the inactive and the hormone-activated state. The preset chromatin exhibits increased histone acetylation but does not cause dissociation of histone H1 as oppose to the hormone-activated state. Furthermore, upon hormone induction the preset MMTV chromatin displays an enhanced and prolonged GR binding capacity and transcription during an intrinsic and time-dependent silencing of the injected template. The silencing process correlates with a reduced histone acetylation. However, a histone deacetylase inhibitor, trichostatin A (TSA), does not counteract silencing in spite of its distinct stimulation of GR-DNA binding. The latter indicates the importance of histone acetylation to maintain DNA access for inducible factor binding. We discuss how constitutively bound factors such as NF1 and Oct1 may participate in the maintenance of tissue specificity of hormone responsive genes.

  4. The receptor guanylyl cyclase type D (GC-D) ligand uroguanylin promotes the acquisition of food preferences in mice.

    Science.gov (United States)

    Arakawa, Hiroyuki; Kelliher, Kevin R; Zufall, Frank; Munger, Steven D

    2013-06-01

    Rodents rely on olfactory stimuli to communicate information between conspecifics that is critical for health and survival. For example, rodents that detect a food odor simultaneously with the social odor carbon disulfide (CS(2)) will acquire a preference for that food. Disruption of the chemosensory transduction cascade in CS(2-)sensitive olfactory sensory neurons (OSNs) that express the receptor guanylyl cyclase type D (GC-D; GC-D+ OSNs) will prevent mice from acquiring these preferences. GC-D+ OSNs also respond to the natriuretic peptide uroguanylin, which is excreted into urine and feces. We analyzed if uroguanylin could also act as a social stimulus to promote the acquisition of food preferences. We found that feces of mice that had eaten odored food, but not unodored food, promoted a strong preference for that food in mice exposed to the feces. Olfactory exploration of uroguanylin presented with a food odor similarly produced a preference that was absent when mice were exposed to the food odor alone. Finally, the acquisition of this preference was dependent on GC-D+ OSNs, as mice lacking GC-D (Gucy2d(-)(/-) mice) showed no preference for the demonstrated food. Together with our previous findings, these results demonstrate that the diverse activators of GC-D+ OSNs elicit a common behavioral result and suggest that this specialized olfactory subsystem acts as a labeled line for a type of associative olfactory learning.

  5. Characterization of dFOXO binding sites upstream of the Insulin Receptor P2 promoter across the Drosophila phylogeny.

    Directory of Open Access Journals (Sweden)

    Dorcas J Orengo

    Full Text Available The insulin/TOR signal transduction pathway plays a critical role in determining such important traits as body and organ size, metabolic homeostasis and life span. Although this pathway is highly conserved across the animal kingdom, the affected traits can exhibit important differences even between closely related species. Evolutionary studies of regulatory regions require the reliable identification of transcription factor binding sites. Here we have focused on the Insulin Receptor (InR expression from its P2 promoter in the Drosophila genus, which in D. melanogaster is up-regulated by hypophosphorylated Drosophila FOXO (dFOXO. We have finely characterized this transcription factor binding sites in vitro along the 1.3 kb region upstream of the InR P2 promoter in five Drosophila species. Moreover, we have tested the effect of mutations in the characterized dFOXO sites of D. melanogaster in transgenic flies. The number of experimentally established binding sites varies across the 1.3 kb region of any particular species, and their distribution also differs among species. In D. melanogaster, InR expression from P2 is differentially affected by dFOXO binding sites at the proximal and distal halves of the species 1.3 kb fragment. The observed uneven distribution of binding sites across this fragment might underlie their differential contribution to regulate InR transcription.

  6. Promoter methylation of protease-activated receptor (PAR2) is associated with severe clinical phenotypes of ulcerative colitis (UC).

    Science.gov (United States)

    Tahara, Tomomitsu; Shibata, Tomoyuki; Nakamura, Masakatsu; Yamashita, Hiromi; Yoshioka, Daisuke; Okubo, Masaaki; Maruyama, Naoko; Kamano, Toshiaki; Kamiya, Yoshio; Fujita, Hiroshi; Nakagawa, Yoshihito; Nagasaka, Mitsuo; Iwata, Masami; Takahama, Kazuya; Watanabe, Makoto; Nakano, Hiroshi; Hirata, Ichiro; Arisawa, Tomiyasu

    2009-06-01

    Tryptase acting at protease-activated receptor 2 (PAR2) contributes to the pathogenesis of Inflammatory bowel diseases (IBDs). DNA methylation has been shown to be an important mechanism in gene silencing. We attempted to clarify the relationship between the promoter methylation of PAR2 and ulcerative colitis (UC). 84 UC patients enrolled in the study. UC patients were classified by disease behavior, severity and extent of disease. For rectal inflammatory mucosal specimens from all the patients, and normal terminal ileum from 23 patients, promoter methylation of PAR2 gene was quantified by digital densitographic analysis following to methylation-specific polymerase chain reaction (MSP). The mean methylation levels of the PAR2 gene in all 84 subjects was 38.4 +/- 19.6%. Although mean methylation levels in rectal inflammatory mucosa, and paired normal terminal ileum did not vary, methylation levels of PAR2 gene was significantly higher in total colitis than rectal colitis (total colitis vs. rectal colitis; 42.9 +/- 19.6% vs. 34.5 +/- 18.9%, P = 0.046). The higher methylation levels were also associated with Steroid-dependent (P = 0.002) and refractory (P = 0.007) UC. Our data suggest that PAR2 methylation status in rectal mucosa correlates with more severe disease phenotypes of UC.

  7. NMDA-Type Glutamate Receptor Activation Promotes Vascular Remodeling and Pulmonary Arterial Hypertension.

    Science.gov (United States)

    Dumas, Sébastien J; Bru-Mercier, Gilles; Courboulin, Audrey; Quatredeniers, Marceau; Rücker-Martin, Catherine; Antigny, Fabrice; Nakhleh, Morad K; Ranchoux, Benoit; Gouadon, Elodie; Vinhas, Maria-Candida; Vocelle, Matthieu; Raymond, Nicolas; Dorfmüller, Peter; Fadel, Elie; Perros, Frédéric; Humbert, Marc; Cohen-Kaminsky, Sylvia

    2018-02-14

    Background -Excessive proliferation and apoptosis resistance in pulmonary vascular cells underlie vascular remodeling in pulmonary arterial hypertension (PAH). Specific treatments for PAH exist, mostly targeting endothelial dysfunction, but high pulmonary arterial pressure still causes heart failure and death. Pulmonary vascular remodeling may be driven by metabolic reprogramming of vascular cells to increase glutaminolysis and glutamate production. The N-methyl-D-aspartate receptor (NMDAR), a major neuronal glutamate receptor, is also expressed on vascular cells, but its role in PAH is unknown. Methods -We assessed the status of the glutamate-NMDAR axis in the pulmonary arteries of PAH patients and controls, through mass spectrometry imaging, western blotting and immunohistochemistry. We measured the glutamate release from cultured pulmonary vascular cells using enzymatic assays, and analyzed NMDAR regulation/phosphorylation through western blot experiments. The effect of NMDAR blockade on human pulmonary arterial smooth muscle cell (hPASMC) proliferation was determined using a BrdU incorporation assay. We assessed the role of NMDARs in vascular remodeling associated to pulmonary hypertension (PH), both in smooth muscle-specific NMDAR knockout mice exposed to chronic hypoxia and in the monocrotaline rat model of PH using NMDAR blockers. Results -We report glutamate accumulation, upregulation of the NMDAR, and NMDAR engagement reflected by increases in GluN1-subunit phosphorylation, in the pulmonary arteries of human PAH patients. K v channel inhibition and ETAR activation amplified calcium-dependent glutamate release from hPASMCs, and ETAR and PDGFR activation led to NMDAR engagement, highlighting crosstalk between the glutamate-NMDAR axis and major PAH-associated pathways. The PDGF-BB-induced proliferation of hPASMCs involved NMDAR activation and phosphorylated GluN1 subunit localization to cell-cell contacts, consistent with glutamatergic communication between

  8. The orphan nuclear receptor Rev-Erbalpha is a peroxisome proliferator-activated receptor (PPAR) gamma target gene and promotes PPARgamma-induced adipocyte differentiation

    DEFF Research Database (Denmark)

    Fontaine, Coralie; Dubois, Guillaume; Duguay, Yannick

    2003-01-01

    Rev-Erbalpha (NR1D1) is an orphan nuclear receptor encoded on the opposite strand of the thyroid receptor alpha gene. Rev-Erbalpha mRNA is induced during adipocyte differentiation of 3T3-L1 cells, and its expression is abundant in rat adipose tissue. Peroxisome proliferator-activated receptor gam...

  9. Adiponectin receptor 1 conserves docosahexaenoic acid and promotes photoreceptor cell survival.

    Science.gov (United States)

    Rice, Dennis S; Calandria, Jorgelina M; Gordon, William C; Jun, Bokkyoo; Zhou, Yongdong; Gelfman, Claire M; Li, Songhua; Jin, Minghao; Knott, Eric J; Chang, Bo; Abuin, Alex; Issa, Tawfik; Potter, David; Platt, Kenneth A; Bazan, Nicolas G

    2015-03-04

    The identification of pathways necessary for photoreceptor and retinal pigment epithelium (RPE) function is critical to uncover therapies for blindness. Here we report the discovery of adiponectin receptor 1 (AdipoR1) as a regulator of these cells' functions. Docosahexaenoic acid (DHA) is avidly retained in photoreceptors, while mechanisms controlling DHA uptake and retention are unknown. Thus, we demonstrate that AdipoR1 ablation results in DHA reduction. In situ hybridization reveals photoreceptor and RPE cell AdipoR1 expression, blunted in AdipoR1(-/-) mice. We also find decreased photoreceptor-specific phosphatidylcholine containing very long-chain polyunsaturated fatty acids and severely attenuated electroretinograms. These changes precede progressive photoreceptor degeneration in AdipoR1(-/-) mice. RPE-rich eyecup cultures from AdipoR1(-/-) reveal impaired DHA uptake. AdipoR1 overexpression in RPE cells enhances DHA uptake, whereas AdipoR1 silencing has the opposite effect. These results establish AdipoR1 as a regulatory switch of DHA uptake, retention, conservation and elongation in photoreceptors and RPE, thus preserving photoreceptor cell integrity.

  10. Cholesterol activates the G-protein coupled receptor Smoothened to promote Hedgehog signaling

    Science.gov (United States)

    Luchetti, Giovanni; Sircar, Ria; Kong, Jennifer H; Nachtergaele, Sigrid; Sagner, Andreas; Byrne, Eamon FX; Covey, Douglas F; Siebold, Christian; Rohatgi, Rajat

    2016-01-01

    Cholesterol is necessary for the function of many G-protein coupled receptors (GPCRs). We find that cholesterol is not just necessary but also sufficient to activate signaling by the Hedgehog (Hh) pathway, a prominent cell-cell communication system in development. Cholesterol influences Hh signaling by directly activating Smoothened (SMO), an orphan GPCR that transmits the Hh signal across the membrane in all animals. Unlike many GPCRs, which are regulated by cholesterol through their heptahelical transmembrane domains, SMO is activated by cholesterol through its extracellular cysteine-rich domain (CRD). Residues shown to mediate cholesterol binding to the CRD in a recent structural analysis also dictate SMO activation, both in response to cholesterol and to native Hh ligands. Our results show that cholesterol can initiate signaling from the cell surface by engaging the extracellular domain of a GPCR and suggest that SMO activity may be regulated by local changes in cholesterol abundance or accessibility. DOI: http://dx.doi.org/10.7554/eLife.20304.001 PMID:27705744

  11. Vitamin D receptor gene polymorphisms, dietary promotion of insulin resistance, and colon and rectal cancer.

    Science.gov (United States)

    Murtaugh, Maureen A; Sweeney, Carol; Ma, Khe-Ni; Potter, John D; Caan, Bette J; Wolff, Roger K; Slattery, Martha L

    2006-01-01

    Modifiable risk factors in colorectal cancer etiology and their interactions with genetic susceptibility are of particular interest. Functional vitamin D receptor (VDR) gene polymorphisms may influence carcinogenesis through modification of cell growth, protection from oxidative stress, cell-cell matrix effects, or insulin and insulin-like growth factor pathways. We investigated interactions between foods (dairy products, red and processed meat, and whole and refined grains) and dietary patterns (sucrose-to-fiber ratio and glycemic index) associated with insulin resistance with the FokI polymorphism of the VDR gene and colon and rectal cancer risk. Data (diet, anthropometrics, and lifestyle) and DNA came from case-control studies of colon (1,698 cases and 1,861 controls) and rectal cancer (752 cases and 960 controls) in northern California, Utah, and the Twin Cities metropolitan area, Minnesota (colon cancer study only). Unconditional logistic regression models were adjusted for smoking, race, sex, age, body mass index, physical activity, energy intake, dietary fiber, and calcium. The lowest colon cancer risk was observed with the Ff/ff FokI genotypes and a low sucrose-to-fiber ratio. Rectal cancer risk decreased with greater consumption of dairy products and increased with red or processed meat consumption and the FF genotype. Modifiable dietary risk factors may be differentially important among individuals by VDR genotype and may act through the insulin pathway to affect colon cancer risk and through fat, calcium, or other means to influence rectal cancer risk.

  12. The export receptor Crm1 forms a dimer to promote nuclear export of HIV RNA.

    Science.gov (United States)

    Booth, David S; Cheng, Yifan; Frankel, Alan D

    2014-12-08

    The HIV Rev protein routes viral RNAs containing the Rev Response Element (RRE) through the Crm1 nuclear export pathway to the cytoplasm where viral proteins are expressed and genomic RNA is delivered to assembling virions. The RRE assembles a Rev oligomer that displays nuclear export sequences (NESs) for recognition by the Crm1-Ran(GTP) nuclear receptor complex. Here we provide the first view of an assembled HIV-host nuclear export complex using single-particle electron microscopy. Unexpectedly, Crm1 forms a dimer with an extensive interface that enhances association with Rev-RRE and poises NES binding sites to interact with a Rev oligomer. The interface between Crm1 monomers explains differences between Crm1 orthologs that alter nuclear export and determine cellular tropism for viral replication. The arrangement of the export complex identifies a novel binding surface to possibly target an HIV inhibitor and may point to a broader role for Crm1 dimerization in regulating host gene expression.

  13. Receptor Mincle promotes skin allergies and is capable of recognizing cholesterol sulfate.

    Science.gov (United States)

    Kostarnoy, Alexey V; Gancheva, Petya G; Lepenies, Bernd; Tukhvatulin, Amir I; Dzharullaeva, Alina S; Polyakov, Nikita B; Grumov, Daniil A; Egorova, Daria A; Kulibin, Andrey Y; Bobrov, Maxim A; Malolina, Ekaterina A; Zykin, Pavel A; Soloviev, Andrey I; Riabenko, Evgeniy; Maltseva, Diana V; Sakharov, Dmitry A; Tonevitsky, Alexander G; Verkhovskaya, Lyudmila V; Logunov, Denis Y; Naroditsky, Boris S; Gintsburg, Alexander L

    2017-03-28

    Sterile (noninfected) inflammation underlies the pathogenesis of many widespread diseases, such as allergies and autoimmune diseases. The evolutionarily conserved innate immune system is considered to play a key role in tissue injury recognition and the subsequent development of sterile inflammation; however, the underlying molecular mechanisms are not yet completely understood. Here, we show that cholesterol sulfate, a molecule present in relatively high concentrations in the epithelial layer of barrier tissues, is selectively recognized by Mincle (Clec4e), a C-type lectin receptor of the innate immune system that is strongly up-regulated in response to skin damage. Mincle activation by cholesterol sulfate causes the secretion of a range of proinflammatory mediators, and s.c. injection of cholesterol sulfate results in a Mincle-mediated induction of a severe local inflammatory response. In addition, our study reveals a role of Mincle as a driving component in the pathogenesis of allergic skin inflammation. In a well-established model of allergic contact dermatitis, the absence of Mincle leads to a significant suppression of the magnitude of the skin inflammatory response as assessed by changes in ear thickness, myeloid cell infiltration, and cytokine and chemokine secretion. Taken together, our results provide a deeper understanding of the fundamental mechanisms underlying sterile inflammation.

  14. Yin Yang 1 Promotes Hepatic Gluconeogenesis Through Upregulation of Glucocorticoid Receptor

    Science.gov (United States)

    Lu, Yan; Xiong, Xuelian; Wang, Xiaolin; Zhang, Zhijian; Li, Jin; Shi, Guojun; Yang, Jian; Zhang, Huijie; Ning, Guang; Li, Xiaoying

    2013-01-01

    Gluconeogenesis is critical in maintaining blood glucose levels in a normal range during fasting. In this study, we investigated the role of Yin Yang 1 (YY1), a key transcription factor involved in cell proliferation and differentiation, in the regulation of hepatic gluconeogenesis. Our data showed that hepatic YY1 expression levels were induced in mice during fasting conditions and in a state of insulin resistance. Overexpression of YY1 in livers augmented gluconeogenesis, raising fasting blood glucose levels in C57BL/6 mice, whereas liver-specific ablation of YY1 using adenoviral shRNA ameliorated hyperglycemia in wild-type and diabetic db/db mice. At the molecular level, we further demonstrated that the major mechanism of YY1 in the regulation of hepatic glucose production is to modulate the expression of glucocorticoid receptor. Therefore, our study uncovered for the first time that YY1 participates in the regulation of hepatic gluconeogenesis, which implies that YY1 might serve as a potential therapeutic target for hyperglycemia in diabetes. PMID:23193188

  15. Acanthamoeba protease activity promotes allergic airway inflammation via protease-activated receptor 2.

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    Mi Kyung Park

    Full Text Available Acanthamoeba is a free-living amoeba commonly present in the environment and often found in human airway cavities. Acanthamoeba possesses strong proteases that can elicit allergic airway inflammation. To our knowledge, the aeroallergenicity of Acanthamoeba has not been reported. We repeatedly inoculated mice with Acanthamoeba trophozoites or excretory-secretory (ES proteins intra-nasally and evaluated symptoms and airway immune responses. Acanthamoeba trophozoites or ES proteins elicited immune responses in mice that resembled allergic airway inflammation. ES proteins had strong protease activity and activated the expression of several chemokine genes (CCL11, CCL17, CCL22, TSLP, and IL-25 in mouse lung epithelial cells. The serine protease inhibitor phenyl-methane-sulfonyl fluoride (PMSF inhibited ES protein activity. ES proteins also stimulated dendritic cells and enhanced the differentiation of naive T cells into IL-4-secreting T cells. After repeated inoculation of the protease-activated receptor 2 knockout mouse with ES proteins, airway inflammation and Th2 immune responses were markedly reduced, but not to basal levels. Furthermore, asthma patients had higher Acanthamoeba-specific IgE titers than healthy controls and we found Acanthamoeba specific antigen from house dust in typical living room. Our findings suggest that Acanthamoeba elicits allergic airway symptoms in mice via a protease allergen. In addition, it is possible that Acanthamoeba may be one of the triggers human airway allergic disease.

  16. Acanthamoeba Protease Activity Promotes Allergic Airway Inflammation via Protease-Activated Receptor 2

    Science.gov (United States)

    Park, Mi Kyung; Cho, Min Kyoung; Kang, Shin Ae; Park, Hye-Kyung; Kim, Dong-Hee; Yu, Hak Sun

    2014-01-01

    Acanthamoeba is a free-living amoeba commonly present in the environment and often found in human airway cavities. Acanthamoeba possesses strong proteases that can elicit allergic airway inflammation. To our knowledge, the aeroallergenicity of Acanthamoeba has not been reported. We repeatedly inoculated mice with Acanthamoeba trophozoites or excretory-secretory (ES) proteins intra-nasally and evaluated symptoms and airway immune responses. Acanthamoeba trophozoites or ES proteins elicited immune responses in mice that resembled allergic airway inflammation. ES proteins had strong protease activity and activated the expression of several chemokine genes (CCL11, CCL17, CCL22, TSLP, and IL-25) in mouse lung epithelial cells. The serine protease inhibitor phenyl-methane-sulfonyl fluoride (PMSF) inhibited ES protein activity. ES proteins also stimulated dendritic cells and enhanced the differentiation of naive T cells into IL-4-secreting T cells. After repeated inoculation of the protease-activated receptor 2 knockout mouse with ES proteins, airway inflammation and Th2 immune responses were markedly reduced, but not to basal levels. Furthermore, asthma patients had higher Acanthamoeba-specific IgE titers than healthy controls and we found Acanthamoeba specific antigen from house dust in typical living room. Our findings suggest that Acanthamoeba elicits allergic airway symptoms in mice via a protease allergen. In addition, it is possible that Acanthamoeba may be one of the triggers human airway allergic disease. PMID:24658532

  17. N-Ethylmaleimide Dissociates α7 ACh Receptor from a Complex with NSF and Promotes Its Delivery to the Presynaptic Membrane.

    Science.gov (United States)

    Nishizaki, Tomoyuki

    2016-08-01

    N-Ethylmaleimide (NEM)-sensitive factor (NSF) associates with soluble NSF attachment protein (SNAP), that binds to SNAP receptors (SNAREs) including syntaxin, SNAP25, and synaptobrevin. The complex of NSF/SNAP/SNAREs plays a critical role in the regulation of vesicular traffic. The present study investigated NEM-regulated α7 ACh receptor translocation. NSF associated with β-SNAP and the SNAREs syntaxin 1 and synaptobrevin 2 in the rat hippocampus. NSF also associated with the α7 ACh receptor subunit, the α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid (AMPA) receptor subunits GluA1 and GluA2, and the γ-aminobutyric acid A (GABAA) receptor γ2 subunit. NEM, an inhibitor of NSF, significantly dissociated the α7 ACh receptor subunit from a complex with NSF and increased cell surface localization of the receptor subunit, but such effect was not obtained with the GluA1, GluA2 or γ2 subunits. NEM, alternatively, dissociated synaptobrevin 2 from an assembly of NSF/β-SNAP/syntaxin 1/synaptobrevin 2. NEM significantly increased the rate of nicotine-triggered AMPA receptor-mediated miniature excitatory postsynaptic currents, without affecting the amplitude, in rat hippocampal slices. The results of the present study indicate that NEM releases the α7 ACh receptor subunit and synaptobrevin 2 from an assembly of α7 ACh receptor subunit/NSF/β-SNAP/syntaxin 1/synaptobrevin 2, thereby promoting delivery of the α7 ACh receptor subunit to presynaptic membrane.

  18. Nogo-66 receptor antagonist peptide (NEP1-40) administration promotes functional recovery and axonal growth after lateral funiculus injury in the adult rat

    NARCIS (Netherlands)

    Cao, Y.; Shumsky, J. S.; Sabol, M. A.; Kushner, R. A.; Strittmatter, S.; Hamers, F. P. T.; Lee, D. H. S.; Rabacchi, S. A.; Murray, M.

    2008-01-01

    Objective. The myelin protein Nogo inhibits axon regeneration by binding to its receptor (NgR) on axons. Intrathecal delivery of an NgR antagonist (NEP1-40) promotes growth of injured corticospinal axons and recovery of motor function following a dorsal hemisection. The authors used a similar design

  19. The promotion of nephropathy byPorphyromonas gingivalislipopolysaccharide via toll-like receptors.

    Science.gov (United States)

    Kajiwara, Koichiro; Takata, Shunsuke; To, Thao T; Takara, Kenyo; Hatakeyama, Yuji; Tamaoki, Sachio; Darveau, Richard Peters; Ishikawa, Hiroyuki; Sawa, Yoshihiko

    2017-01-01

    Recently, we reported that toll-like receptor (TLR)2 and TLR4 localized on the glomerular endothelium in the glomeruli of streptozotocin (STZ)-induced type 1 diabetic mice and high fat diet feed-induced type 2 diabetic mice, and that periodontal pathogen Porphyromonas gingivalis LPS (Pg-LPS) administration lowered the survival rate of diabetic mice. The present study aims to examine the effect of TLR4 blocking on the suppression of Pg-LPS-induced diabetic nephropathy. The survival rate and morphological/biochemical features for streptozotocin-induced diabetic mice with Pg-LPS and TLR4 blocker eritoran administration were investigated by reporter gene assay, urine and blood analysis, immunohistochemistry, and real time-PCR. All of the diabetic mice administered Pg-LPS were euthanized within the survival period of almost all of the diabetic mice. The blood urea nitrogen and creatinine, expression of TLR2 and TGF-b, and type 1 collagen accumulation, in the diabetic mice increased significantly with the Pg-LPS administration. In spite of the limited TLR4 activation with Pg-LPS, the TLR4 blocker eritoran decreased blood urea nitrogen and creatinine, and raised the survival rate of the Pg-LPS-administered diabetic mice slightly. The high expression levels of TLR2, TGF-b, and type 1 collagen in Pg-LPS-administered diabetic mice decreased with eritoran. Nuclear STAT3 which enhances TLR2 expression was detected in the TLR2-expressing glomeruli of diabetic mice. The TLR2 and STAT3 gene expression increased by the Pg-LPS administration but decreased with eritoran. These may suggest that Pg-LPS-induced diabetic nephropathy is mainly dependent on TLR2 signaling on glomerular endothelial cells, and that TLR4 blocker eritoran may play a role to slow the progress of diabetic nephropathy.

  20. An Accessory Agonist Binding Site Promotes Activation of α4β2* Nicotinic Acetylcholine Receptors.

    Science.gov (United States)

    Wang, Jingyi; Kuryatov, Alexander; Sriram, Aarati; Jin, Zhuang; Kamenecka, Theodore M; Kenny, Paul J; Lindstrom, Jon

    2015-05-29

    Neuronal nicotinic acetylcholine receptors containing α4, β2, and sometimes other subunits (α4β2* nAChRs) regulate addictive and other behavioral effects of nicotine. These nAChRs exist in several stoichiometries, typically with two high affinity acetylcholine (ACh) binding sites at the interface of α4 and β2 subunits and a fifth accessory subunit. A third low affinity ACh binding site is formed when this accessory subunit is α4 but not if it is β2. Agonists selective for the accessory ACh site, such as 3-[3-(3-pyridyl)-1,2,4-oxadiazol-5-yl]benzonitrile (NS9283), cannot alone activate a nAChR but can facilitate more efficient activation in combination with agonists at the canonical α4β2 sites. We therefore suggest categorizing agonists according to their site selectivity. NS9283 binds to the accessory ACh binding site; thus it is termed an accessory site-selective agonist. We expressed (α4β2)2 concatamers in Xenopus oocytes with free accessory subunits to obtain defined nAChR stoichiometries and α4/accessory subunit interfaces. We show that α2, α3, α4, and α6 accessory subunits can form binding sites for ACh and NS9283 at interfaces with α4 subunits, but β2 and β4 accessory subunits cannot. To permit selective blockage of the accessory site, α4 threonine 126 located on the minus side of α4 that contributes to the accessory site, but not the α4β2 sites, was mutated to cysteine. Alkylation of this cysteine with a thioreactive reagent blocked activity of ACh and NS9283 at the accessory site. Accessory agonist binding sites are promising drug targets. © 2015 by The American Society for Biochemistry and Molecular Biology, Inc.

  1. Kinin B1 Receptor Promotes Neurogenic Hypertension Through Activation of Centrally Mediated Mechanisms.

    Science.gov (United States)

    Sriramula, Srinivas; Lazartigues, Eric

    2017-12-01

    Hypertension is associated with increased activity of the kallikrein-kinin system. Kinin B1 receptor (B1R) activation leads to vasoconstriction and inflammation. Despite evidence supporting a role for the B1R in blood pressure regulation, the mechanisms by which B1R could alter autonomic function and participate in the pathogenesis of hypertension remain unidentified. We sought to explore whether B1R-mediated inflammation contributes to hypertension and investigate the molecular mechanisms involved. In this study, we tested the hypothesis that activation of B1R in the brain is involved in the pathogenesis of hypertension, using the deoxycorticosterone acetate-salt model of neurogenic hypertension in wild-type and B1R knockout mice. Deoxycorticosterone acetate-salt treatment in wild-type mice led to significant increases in B1R mRNA and protein levels and bradykinin levels, enhanced gene expression of carboxypeptidase N supporting an increase in the B1R ligand, associated with enhanced blood pressure, inflammation, sympathoexcitation, autonomic dysfunction, and impaired baroreflex sensitivity, whereas these changes were blunted or prevented in B1R knockout mice. B1R stimulation was further shown to involve activation of the ASK1-JNK-ERK1/2 and NF-κB pathways in the brain. To dismiss potential developmental alterations in knockout mice, we further used B1R blockade selectively in the brain of wild-type mice. Supporting the central origin of this mechanism, intracerebroventricular infusion of a specific B1R antagonist, attenuated the deoxycorticosterone acetate-salt-induced increase in blood pressure in wild-type mice. Our data provide the first evidence of a central role for B1R-mediated inflammatory pathways in the pathogenesis of deoxycorticosterone acetate-salt hypertension and offer novel insights into possible B1R-targeted therapies for the treatment of neurogenic hypertension. © 2017 American Heart Association, Inc.

  2. ST6Gal-I sialyltransferase promotes tumor necrosis factor (TNF)-mediated cancer cell survival via sialylation of the TNF receptor 1 (TNFR1) death receptor.

    Science.gov (United States)

    Holdbrooks, Andrew T; Britain, Colleen M; Bellis, Susan L

    2018-02-02

    Activation of the tumor necrosis factor receptor 1 (TNFR1) death receptor by TNF induces either cell survival or cell death. However, the mechanisms mediating these distinct outcomes remain poorly understood. In this study, we report that the ST6Gal-I sialyltransferase, an enzyme up-regulated in numerous cancers, sialylates TNFR1 and thereby protects tumor cells from TNF-induced apoptosis. Using pancreatic and ovarian cancer cells with ST6Gal-I knockdown or overexpression, we determined that α2-6 sialylation of TNFR1 had no effect on early TNF-induced signaling events, including the rapid activation of NF-κB, c-Jun N-terminal kinase (JNK), extracellular signal-regulated kinase (ERK), and Akt (occurring within 15 min). However, upon extended TNF treatment (6-24 h), cells with high ST6Gal-I levels exhibited resistance to TNF-induced apoptosis, as indicated by morphological evidence of cell death and decreased activation of caspases 8 and 3. Correspondingly, at these later time points, high ST6Gal-I expressers displayed sustained activation of the survival molecules Akt and NF-κB. Additionally, extended TNF treatment resulted in the selective enrichment of clonal variants with high ST6Gal-I expression, further substantiating a role for ST6Gal-I in cell survival. Given that TNFR1 internalization is known to be essential for apoptosis induction, whereas survival signaling is initiated by TNFR1 at the plasma membrane, we examined TNFR1 localization. The α2-6 sialylation of TNFR1 was found to inhibit TNF-induced TNFR1 internalization. Thus, by restraining TNFR1 at the cell surface via sialylation, ST6Gal-I acts as a functional switch to divert signaling toward survival. These collective findings point to a novel glycosylation-dependent mechanism that regulates the cellular response to TNF and may promote cancer cell survival within TNF-rich tumor microenvironments. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  3. [Metabotropic glutamate receptor 8 activation promotes the apoptosis of lung carcinoma A549 cells in vitro].

    Science.gov (United States)

    Li, Tian-Jiao; Huang, Yan-Hong; Chen, Xi; Zhou, Zhou; Luo, Si-Wei; Feng, Dan-Dan; Han, Jian-Zhong; Luo, Zi-Qiang

    2015-10-25

    This study aims to detect the expression of metabotropic glutamate receptors (mGluRs) in lung carcinoma A549 cells, and to investigate the effects of mGluR8 and mGluR4 activation on the growth of A549 cells in vitro. The mRNA expression levels of the 8 subtypes of mGluRs in A549 cells were determined by real-time PCR. Immunohistochemistry was used to analyze the protein expression of mGluR4 and mGluR8 in A549 cells and lung tissue sections obtained from lung adenocarcinoma patients. To observe the effects of mGluR8 and mGluR4 activation on the growth of A549 cells, the cultured cells were treated with (S)-3,4-DCPG (an agonist of mGluR8) and VU0155041 (an agonist of mGluR4), respectively, and then the cell viability was analyzed by CCK-8 kit, the percentage of DNA synthesis was detected by EdU incorporation, and the apoptosis of the cells was measured by hoechst 33258 staining and flow cytometry. The results showed that there were low expressions of mGluR1, mGluR5, mGluR6, mGluR7 mRNA, no expression of mGluR2 and mGluR3 mRNA, and high expressions of mGluR8 and mGluR4 mRNA in A549 cells. Accordingly, there were also mGluR4 and mGluR8 protein expressions in the A549 cells and the lung adenocarcinoma tissue sections. VU0155041 had no effect on the growth of A549 cells, but (S)-3,4-DCPG significantly decreased the cells' growth in a dose-dependent manner and increased the apoptosis of the cells. The results revealed a role of mGluR8 in the growth and apoptosis of A549 cells and suggested a potential target for clinical treatment of lung cancer.

  4. Activation of olfactory receptors on mouse pulmonary macrophages promotes monocyte chemotactic protein-1 production.

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    Jing Jing Li

    Full Text Available BACKGROUND: Emerging evidence suggests that non-olfactory tissues and cells can express olfactory receptors (ORs, however, the exact function of ectopic OR expression remains unknown. We have previously shown in mouse models that a unique cooperation between interferon-γ (IFN-γ and lipopolysaccharide (LPS drives the activation of pulmonary macrophages and leads to the induction of pathogenic responses in the respiratory tract. Further, through gene array studies, we have shown that activation of macrophages by these molecules results in the selective expression of a number of ORs. In this study, we validated the expression of these ORs in mouse airway and pulmonary macrophages in response to IFN-γ and LPS (γ/LPS stimulation, and further explored the effect of odorant stimulation on macrophage function. METHODOLOGY/PRINCIPAL FINDINGS: OR expression in airway and pulmonary macrophages in response to IFN-γ, LPS or γ/LPS treatments was assessed by microarray and validated by q-PCR. OR expression (e.g. OR622 on macrophages was confirmed by visualization in immunofluoresence assays. Functional responses to odorants were assessed by quantifying inflammatory cytokine and chemokine expression using q-PCR and cell migration was assessed by a modified Boyden chamber migration assay. Our results demonstrate that eight ORs are expressed at basal levels in both airway and pulmonary macrophages, and that γ/LPS stimulation cooperatively increased this expression. Pulmonary macrophages exposed to the combined treatment of γ/LPS+octanal (an odorant exhibited a 3-fold increase in MCP-1 protein production, compared to cells treated with γ/LPS alone. Supernatants from γ/LPS+octanal exposed macrophages also increased macrophage migration in vitro. CONCLUSIONS/SIGNIFICANCE: Eight different ORs are expressed at basal levels in pulmonary macrophages and expression is upregulated by the synergistic action of γ/LPS. Octanal stimulation further increased MCP-1

  5. The β-glucan fromLentinus edodessuppresses cell proliferation and promotes apoptosis in estrogen receptor positive breast cancers.

    Science.gov (United States)

    Xu, Hui; Zou, Siwei; Xu, Xiaojuan

    2017-10-17

    Breast cancer is now the most common cancer in worldwide women, and novel interventions are needed to overcome the resistance occurring in the estrogen-targeted endocrine therapy. Herein, we demonstrate that the β-glucan from Lentinus edodes (LNT) exhibited a profound inhibition ratio of ∼53% against estrogen receptor positive (ER+) MCF-7 tumor growth in nude mice similar to the positive control of cisplatin. Immunohistochemistry images showed that LNT evidently suppressed cell proliferation and promoted apoptosis in MCF-7 tumor tissues. The Western blotting analysis indicated that LNT up-regulated the tumor suppressor p53, phosphorylated extracellular signal-regulated kinase1/2 (p-ERK1/2), cleaved-Caspase 3 and poly [ADP (ribose)] polymerase 1 (PARP 1) protein levels, and reduced the expression of mouse double minute 2 (MDM2), telomerase reverse transcriptase (TERT), nuclear factor-kappa B (NF-κB) p65, B-cell lymphoma-2 (Bcl-2), estrogen receptor α (ERα), etc. in tumor tissues. Moreover, LNT significantly suppressed phosphatidylinositol 3-kinase (PI3K), phosphorylated protein kinase B (p-Akt) and mammalian target of rapamycin (mTOR) protein levels. It was thus proposed that LNT inhibited MCF-7 tumor growth through suppressing cell proliferation and enhancing apoptosis possibly via multiple pathways such as PI3K/Akt/mTOR, NF-κB-, ERK-, ERα-, caspase- and p53-dependent pathways. Interestingly, the cell viability assay, siRNA transfection, Western blotting and flow cytometric analysis suggested that LNT targeted p53/ERα to only suppress cell proliferation via cell cycle arrest at G2/M phase without apoptosis in vitro . The big difference between in vivo and in vitro data suggested that the immune responses triggered by the polysaccharide should mainly contribute to the apoptotic effect in vivo . Overall, this work provides a novel strategy to treat ER+ breast cancers by using a naturally occurring β-glucan from mushrooms.

  6. p130Cas substrate domain signaling promotes migration, invasion, and survival of estrogen receptor-negative breast cancer cells

    Directory of Open Access Journals (Sweden)

    Anna C Cunningham-Edmondson

    2009-12-01

    Full Text Available Anna C Cunningham-Edmondson1,2, Steven K Hanks11Department of Cell and Developmental Biology, Vanderbilt University School of Medicine, Nashville, TN, USA; 2Department of Cellular Biology and Anatomy, Medical College of Georgia, Augusta, GA, USAAbstract: Elevated Src tyrosine kinase activity is commonly observed in breast cancer and likely contributes to neoplasia and malignancy. p130Cas (“Crk-associated substrate” is a major Src substrate found at the sites where integrins mediate cell adhesion to the extracellular matrix. Src phosphorylates multiple tyrosines in the p130Cas “substrate domain” (SD and this signaling event has been implicated in the promotion of cell motility, primarily from studies on fibroblasts. In breast cancer, studies on p130Cas have focused on its role in conferring antiestrogen resistance to cells that express the estrogen receptor (ER+. However, little is known regarding the role of p130Cas in the more aggressive estrogen receptor negative (ER- breast cancers for which there is a need for development of effective targeted therapies. We found high levels of p130Cas SD tyrosine phosphorylation to be a common characteristic of ER- breast cancer cell lines, with particularly high levels observed for the BT-549 cell line. Using RNA interference to knock down p130Cas expression in BT-549 cells, combined with rescue by WT p130Cas versus a signaling-deficient control, we provide evidence that p130Cas SD tyrosine phosphorylation is an important signaling event in the migration, invasion, proliferation, and survival of this ER- breast cancer cell line.Keywords: adhesion, BCAR1, integrins, Src, FAK, tyrosine phosphorylation

  7. Hypoxia and prostaglandin E receptor 4 signalling pathways synergise to promote endometrial adenocarcinoma cell proliferation and tumour growth.

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    Rob D Catalano

    Full Text Available The prostaglandin endoperoxide synthase (PTGS pathway is a potent driver of tumour development in humans by enhancing the biosynthesis and signalling of prostaglandin (PG E(2. PTGS2 expression and PGE(2 biosynthesis is elevated in endometrial adenocarcinoma, however the mechanism whereby PTGS and PGE(2 regulate endometrial tumour growth is unknown. Here we investigated (a the expression profile of the PGE synthase enzymes (PTGES, PTGES-2, PTGES-3 and PGE receptors (PTGER1-4 in endometrial adenocarcinomas compared with normal endometrium and (b the role of PTGER4 in endometrial tumorigenesis in vivo. We found elevated expression of PTGES2 and PTGER4 and suppression of PTGER1 and PTGER3 in endometrial adenocarcinomas compared with normal endometrium. Using WT Ishikawa endometrial adenocarcinoma cells and Ishikawa cells stably transfected with the full length PTGER4 cDNA (PTGER4 cells xenografted in the dorsal flanks of nude mice, we show that PTGER4 rapidly and significantly enhances tumour growth rate. Coincident with enhanced PTGER4-mediated tumour growth we found elevated expression of PTGS2 in PTGER4 xenografts compared with WT xenografts. Furthermore we found that the augmented growth rate of the PTGER4 xenografts was not due to enhanced angiogenesis, but regulated by an increased proliferation index and hypoxia. In vitro, we found that PGE(2 and hypoxia independently induce expression of PTGER4 indicating two independent pathways regulating prostanoid receptor expression. Finally we have shown that PGE(2 and hypoxia synergise to promote cellular proliferation of endometrial adenocarcinoma cells.

  8. Estrogen receptor {alpha} gene promoter 0/B usage in the rat sexually dimorphic nucleus of the preoptic area.

    Science.gov (United States)

    Hamada, Tomohiro; Sakuma, Yasuo

    2010-04-01

    The volume of the sexually dimorphic nucleus of the preoptic area (SDN-POA) is two to four times larger in male rats than in females; however, the mechanism for the establishment of sexual dimorphism and the function of this nucleus is almost unknown. Perinatal estrogen can cause sexual dimorphism via the estrogen receptor alpha (ERalpha). Recently, transgenic rats were generated that express enhanced green fluorescent protein (EGFP) under the control of the ERalpha gene promoter 0/B to tag ERalpha-positive neurons in the brain. In the present study, we examined whether this EGFP expression could be a marker for the SDN-POA in adults. EGFP-labeled cells were distributed in the core of the SDN-POA (0/B-SDN) of male and female transgenic rats, in accordance with the Nissl staining and immunoreactivity for the SDN marker, calbindin. They were also immunoreactive for ERalpha. The core was bigger in volume and contained more 0/B-SDN neurons in males than in females. The EGFP-tagged cells were packed more densely in the female core than that in males. Subcutaneous injection of 100 mug 17beta-estradiol to females on the day of birth, or orchidectomy of male neonates, reversed the sexually dimorphic phenotype of the volume of the 0/B-SDN, despite not affecting the cell number. We suggest that this EGFP expression in the SDN-POA could be a useful marker to clarify the sexual differentiation and function of the SDN-POA. Moreover, the ERalpha gene promoter 0/B plays a key role in the organization of the sexual differentiation of the SDN-POA.

  9. High calcium concentration in bones promotes bone metastasis in renal cell carcinomas expressing calcium-sensing receptor.

    Science.gov (United States)

    Joeckel, Elke; Haber, Tobias; Prawitt, Dirk; Junker, Kerstin; Hampel, Christian; Thüroff, Joachim W; Roos, Frederik C; Brenner, Walburgis

    2014-02-28

    The prognosis for renal cell carcinoma (RCC) is related to a high rate of metastasis, including 30% of bone metastasis. Characteristic for bone tissue is a high concentration of calcium ions. In this study, we show a promoting effect of an enhanced extracellular calcium concentration on mechanisms of bone metastasis via the calcium-sensing receptor (CaSR) and its downstream signaling molecules. Our analyses were performed using 33 (11/category) matched specimens of normal and tumor tissue and 9 (3/category) primary cells derived from RCC patients of the 3 categories: non-metastasized, metastasized into the lung and metastasized into bones during a five-year period after nephrectomy. Expression of CaSR was determined by RT-PCR, Western blot analyses and flow cytometry, respectively. Cells were treated by calcium and the CaSR inhibitor NPS 2143. Cell migration was measured in a Boyden chamber with calcium (10 μM) as chemotaxin and proliferation by BrdU incorporation. The activity of intracellular signaling mediators was quantified by a phospho-kinase array and Western blot. The expression of CaSR was highest in specimens and cells of patients with bone metastases. Calcium treatment induced an increased migration (19-fold) and proliferation (2.3-fold) exclusively in RCC cells from patients with bone metastases. The CaSR inhibitor NPS 2143 elucidated the role of CaSR on the calcium-dependent effects. After treatment with calcium, the activity of AKT, PLCγ-1, p38α and JNK was clearly enhanced and PTEN expression was almost completely abolished in bone metastasizing RCC cells. Our results indicate a promoting effect of extracellular calcium on cell migration and proliferation of bone metastasizing RCC cells via highly expressed CaSR and its downstream signaling pathways. Consequently, CaSR may be regarded as a new prognostic marker predicting RCC bone metastasis.

  10. receptores

    Directory of Open Access Journals (Sweden)

    Salete Regina Daronco Benetti

    2006-01-01

    Full Text Available Se trata de un estudio etnográfico, que tuvo lo objetivo de interpretar el sistema de conocimiento y del significado atribuidos a la sangre referente a la transfusión sanguínea por los donadores y receptores de un banco de sangre. Para la colecta de las informaciones se observaron los participantes y la entrevista etnográfica se realizó el análisis de dominio, taxonómicos y temáticos. Los dominios culturales fueron: la sangre es vida: fuente de vida y alimento valioso; creencias religiosas: fuentes simbólicas de apoyos; donación sanguínea: un gesto colaborador que exige cuidarse, gratifica y trae felicidad; donación sanguínea: fuente simbólica de inseguridad; estar enfermo es una condición para realizar transfusión sanguínea; transfusión sanguínea: esperanza de vida; Creencias populares: transfusión sanguínea como riesgo para la salud; donadores de sangre: personas benditas; donar y recibir sangre: como significado de felicidad. Temática: “líquido precioso que origina, sostiene, modifica la vida, provoca miedo e inseguridad”.

  11. Toll-like receptor 4 promotes angiogenesis in pancreatic cancer via PI3K/AKT signaling

    Energy Technology Data Exchange (ETDEWEB)

    Sun, Yunliang; Wu, Congshan [Department of Gastroenterology, Lianyungang Ganyu People’s Hospital, Ganyu, Jiangsu (China); Ma, Jianxia, E-mail: yz_mjx@163.com [Department of Gastroenterology, Huadong Hospital, Fudan University, Shanghai (China); Yang, Yu [Department of Gastroenterology, Huadong Hospital, Fudan University, Shanghai (China); Man, Xiaohua; Wu, Hongyu; Li, Shude [Department of Gastroenterology, Changhai Hospital, The Second Military Medical University, Shanghai (China)

    2016-10-01

    Deregulation of Toll-like receptor 4 (TLR4) is closely associated with the progression of various types of cancers, but its role in pancreatic carcinogenesis is unclear. This study aimed to investigate the role of TLR4 in the angiogenesis of pancreatic cancer and the underlying molecular mechanisms. The culture supernatant (conditioned medium) of PANC-1 cells after appropriate treatment was used for the treatment of HUVECs. The proliferation, migration and tube formation of HUVECs were assessed by MTT, Transwell and Matrigel, respectively. In pancreatic cancer tissues, TLR4, VEGF and CD31 were upregulated as determined by immunohistochemistry and the expression of TLR4 and VEGF was positively correlated with microvessel density as detected by CD31 staining. Activation of TLR4 signaling by LPS in PANC-1 cells resulted in increased VEGF and phosphorylation of AKT, which were abolished by TLR4 silencing with siRNA and PI3K/AKT signaling inhibitor LY294002. The conditioned medium from PANC-1 cells treated with LY294002 or transfected with TRL4 siRNA reduced the proliferation, migration and tube formation of HUVECs. In contrast, the conditioned medium from PANC-1 cells treated with LPS stimulated the proliferation, migration and tube formation of HUVECs, which was however significantly inhibited by pretreatment of PANC-1 cells with LY294002 or transfection with TRL4 siRNA. Our findings suggest TLR4 may promote angiogenesis in pancreatic cancer by activating the PI3K/AKT signaling pathway to induce VEGF expression.

  12. A variant on promoter of the cannabinoid receptor 1 gene (CNR1) moderates the effect of valence on working memory.

    Science.gov (United States)

    Fairfield, Beth; Mammarella, Nicola; Franzago, Marica; Di Domenico, Alberto; Stuppia, Liborio; Gatta, Valentina

    2018-02-01

    Cannabinoid receptor 1 gene (CNR1) variants have been related to affective information processing and, in particular, to stress release. Here, we aimed to examine whether the endocannabinoid system via CNR1 signaling modulates affective working memory, the memory system that transiently maintains and manipulates emotionally charged material. We focused on rs2180619 (A > G) polymorphism and examined genotype data collected from 231 healthy females. Analyses showed how a general positivity bias in working memory (i.e., better memory for positive words) emerged as task strings lengthened only in carriers of the major allele (AA/AG). Differently, GG carriers showed better memory for affective items in general (i.e., positive and negative words). These findings are some of the first to directly highlight the role of variant on promoter of the CNR1 gene in affective working memory and to evidence a differentiation among CNR1 genotypes in terms of larger difficulties in disengaging from negative stimuli in GG carriers.

  13. Serotonin receptor 1A promoter polymorphism, rs6295, modulates human anxiety levels via altering parasympathetic nervous activity.

    Science.gov (United States)

    Huang, J-H; Chang, H-A; Fang, W-H; Ho, P-S; Liu, Y-P; Wan, F-J; Tzeng, N-S; Shyu, J-F; Chang, C-C

    2018-03-01

    The G-allele of the -1019C/G (rs6295) promoter polymorphism of the serotonin receptor 1A (HTR1A) gene has been implicated in anxiety; however, the underlying neurophysiological processes are still not fully understood. Recent evidence indicates that low parasympathetic (vagal) tone is predictive of anxiety. We thus conducted a structural equation model (SEM) to examine whether the HTR1A rs6295 variant can affect anxiety by altering parasympathetic nervous activity. A sample of 1141 drug-free healthy Han Chinese was recruited for HTR1A genotyping. Autonomic nervous function was assessed by short-term spectral analysis of heart rate variability (HRV). Anxiety and stress levels were evaluated by the Beck Anxiety Inventory (BAI) and the Perceived Stress Scale (PSS) respectively. The number of the HTR1A G allele was inversely correlated with high-frequency power (HF), a parasympathetic index of HRV. The HF index was negatively associated with BAI scores. Furthermore, the good-fitting SEM, adjusting for confounding variables (e.g., age and PSS levels), revealed a significant pathway linking rs6295 variant to BAI scores via HF index modulation. These results are the first to show that HTR1A -1019C/G polymorphism influences anxiety levels by modulating parasympathetic tone, providing a neurophysiological insight into the role of HTR1A in human anxiety. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  14. Wake-promoting effects of ONO-4127Na, a prostaglandin DP1 receptor antagonist, in hypocretin/orexin deficient narcoleptic mice.

    Science.gov (United States)

    Sagawa, Yohei; Sato, Masatoshi; Sakai, Noriaki; Chikahisa, Sachiko; Chiba, Shintaro; Maruyama, Takashi; Yamamoto, Junki; Nishino, Seiji

    2016-11-01

    Prostaglandin (PG)D2 is an endogenous sleep substance, and a series of animal studies reported that PGD2 or PGD2 receptor (DP1) agonists promote sleep, while DP1 antagonists promote wakefulness. This suggests the possibility of use of PG DP1 antagonists as wake-promoting compounds. We therefore evaluated the wake-promoting effects of ONO-4127Na, a DP1 antagonist, in a mouse model of narcolepsy (i.e., orexin/ataxin-3 transgenic mice) and compared those to effects of modafinil. ONO-4127Na perfused in the basal forebrain (BF) area potently promoted wakefulness in both wild type and narcoleptic mice, and the wake-promoting effects of ONO-4127Na at 2.93 × 10(-4) M roughly corresponded to those of modafinil at 100 mg/kg (p.o.). The wake promoting effects of ONO-4127Na was observed both during light and dark periods, and much larger effects were seen during the light period when mice slept most of the time. ONO-4127Na, when perfused in the hypothalamic area, had no effects on sleep. We further demonstrated that wake-promoting effects of ONO-4127Na were abolished in DP1 KO mice, confirming that the wake-promoting effect of ONO-4127Na is mediated by blockade of the PG DP1 receptors located in the BF area. ONO-4127Na reduced DREM, an EEG/EMG assessment of behavioral cataplexy in narcoleptic mice, suggesting that ONO-4127Na is likely to have anticataplectic effects. DP1 antagonists may be a new class of compounds for the treatment of narcolepsy-cataplexy, and further studies are warranted. Copyright © 2016 Elsevier Ltd. All rights reserved.

  15. PGE2 promotes breast cancer-associated lymphangiogenesis by activation of EP4 receptor on lymphatic endothelial cells.

    Science.gov (United States)

    Nandi, Pinki; Girish, Gannareddy V; Majumder, Mousumi; Xin, Xiping; Tutunea-Fatan, Elena; Lala, Peeyush K

    2017-01-05

    Lymphatic metastasis, facilitated by lymphangiogenesis is a common occurrence in breast cancer, the molecular mechanisms remaining incompletely understood. We had earlier shown that cyclooxygenase (COX)-2 expression by human or murine breast cancer cells promoted lymphangiogenesis and lymphatic metastasis by upregulating VEGF-C/D production by tumor cells or tumor-associated macrophages primarily due to activation of the prostaglandin receptor EP4 by endogenous PGE2. It is not clear whether tumor or host-derived PGE2 has any direct effect on lymphangiogenesis, and if so, whether EP4 receptors on lymphatic endothelial cells (LEC) play any role. Here, we address these questions employing in vitro studies with a COX-2-expressing and VEGF-C/D-producing murine breast cancer cell line C3L5 and a rat mesenteric (RM) LEC line and in vivo studies in nude mice. RMLEC responded to PGE2, an EP4 agonist PGE1OH, or C3L5 cell-conditioned media (C3L5-CM) by increased proliferation, migration and accelerated tube formation on growth factor reduced Matrigel. Native tube formation by RMLEC on Matrigel was abrogated in the presence of a selective COX-2 inhibitor or an EP4 antagonist. Addition of PGE2 or EP4 agonist, or C3L5-CM individually in the presence of COX-2 inhibitor, or EP4 antagonist, restored tube formation, reinforcing the role of EP4 on RMLEC in tubulogenesis. These results were partially duplicated with a human dermal LEC (HMVEC-dLyAd) and a COX-2 expressing human breast cancer cell line MDA-MB-231. Knocking down EP4 with shRNA in RMLEC abrogated their tube forming capacity on Matrigel in the absence or presence of PGE2, EP4 agonist, or C3L5-CM. RMLEC tubulogenesis following EP4 activation by agonist treatment was dependent on PI3K/Akt and Erk signaling pathways and VEGFR-3 stimulation. Finally in a directed in vivo lymphangiogenesis assay (DIVLA) we demonstrated the lymphangiogenic as well as angiogenic capacity of PGE2 and EP4 agonist in vivo. These results demonstrate

  16. Testicular orphan nuclear receptor 4-associated protein 16 promotes non-small cell lung carcinoma by activating estrogen receptor β and blocking testicular orphan nuclear receptor 2.

    Science.gov (United States)

    Fang, Fang; Zheng, Qingfeng; Zhang, Jianzhi; Dong, Bin; Zhu, Sainan; Huang, Xiaoyun; Wang, Yang; Zhao, Bingtian; Li, Shaolei; Xiong, Hongchao; Chen, Jinfeng; Wu, Nan; Song, Sonya Wei; Chang, Chawnshang; Yang, Yue

    2013-01-01

    The possible involvement of estrogen receptors (ERs) and testicular orphan nuclear receptors (TRs) in human non-small cell lung carcinoma (NSCLC) has been suggested, but their precise roles and their relationship remain largely unknown. This study aimed to investigate whether TR4-associated protein 16 (TRA16) regulates the ERβ and TR2 pathways and could be a potential target in NSCLC. We used tissue microarrays including NSCLC tissues (n=154) and negative controls (n=14) to examine the expression of TRA16 and ERβ, and in vitro reporter gene assays, the mammalian two-hybrid method and immunoprecipitation in Cos-1 cells to investigate the relationships among TRA16, ERβ and TR2. We found that TRA16 was highly expressed in approximately 90% of the NSCLC tissues examined. TRA16 overexpression was significantly associated with TNM stage, tumor size, lymph node metastasis, tumor thrombus in vein, tumor differentiation and prognosis of NSCLC patients, in which TRA16 was shown to be an independent prognostic factor. Introduction of TRA16 into Cos-1 cells enhanced cell proliferation. Co-expression of TRA16 and ERβ in Cos-1 cells using different reporter gene systems and mammalian two-hybrid approaches revealed that TRA16 enhanced ERβ-mediated transcriptional activity. By adopting similar approaches, and immunoprecipitation and immunocytofluorescence assays, we found that TRA16 also interacted with TR2, and blocked the TR2 inhibitory effect on ERβ. Our findings demonstrate that TRA16 could be a promising diagnostic and prognostic biomarker in NSCLC, and promotes cancer cell growth through activation of the ERβ pathway by interacting with ERβ and TR2.

  17. Retinoic Acid Receptor β Stimulates Hepatic Induction of Fibroblast Growth Factor 21 to Promote Fatty Acid Oxidation and Control Whole-body Energy Homeostasis in Mice*

    Science.gov (United States)

    Li, Yu; Wong, Kimberly; Walsh, Kenneth; Gao, Bin; Zang, Mengwei

    2013-01-01

    Activation of retinoic acid receptor (RAR) with all-trans-retinoic acid (RA) ameliorates glucose intolerance and insulin resistance in obese mice. The recently discovered fibroblast growth factor 21 (FGF21) is a hepatocyte-derived hormone that restores glucose and lipid homeostasis in obesity-induced diabetes. However, whether hepatic RAR is linked to FGF21 in the control of lipid metabolism and energy homeostasis remains elusive. Here we identify FGF21 as a direct target gene of RARβ. The gene transcription of Fgf21 is increased by the RAR agonist RA and by overexpression of RARα and RARβ, but it is unaffected by RARγ in HepG2 cells. Promoter deletion analysis characterizes a putative RA-responsive element (RARE) primarily located in the 5′-flanking region of the Fgf21 gene. Disruption of the RARE sequence abolishes RA responsiveness. In vivo adenoviral overexpression of RARβ in the liver enhances production and secretion of FGF21, which in turn promotes hepatic fatty acid oxidation and ketogenesis and ultimately leads to increased energy expenditure in mice. The metabolic effects of RA or RARβ are mimicked by FGF21 overexpression and largely abolished by FGF21 knockdown. Moreover, hepatic RARβ is bound to the putative RAREs of the Fgf21 promoter in a fasting-inducible manner in vivo, which contributes to FGF21 induction and the metabolic adaptation to prolonged fasting. In addition to other nuclear receptors, such as peroxisome proliferator-activated receptor α and retinoic acid receptor-related receptor α, RAR may act as a novel component to induce hepatic FGF21 in the regulation of lipid metabolism. The hepatic RAR-FGF21 pathway may represent a potential drug target for treating metabolic disorders. PMID:23430257

  18. Toll-like receptor 2 promotes neurogenesis from the dentate gyrus after photothrombotic cerebral ischemia in mice.

    Science.gov (United States)

    Seong, Kyung-Joo; Kim, Hyeong-Jun; Cai, Bangrong; Kook, Min-Suk; Jung, Ji-Yeon; Kim, Won-Jae

    2018-03-01

    The subgranular zone (SGZ) of hippocampal dentate gyrus (HDG) is a primary site of adult neurogenesis. Toll-like receptors (TLRs), are involved in neural system development of Drosophila and innate immune response of mammals. TLR2 is expressed abundantly in neurogenic niches such as adult mammalian hippocampus. It regulates adult hippocampal neurogenesis. However, the role of TLR2 in adult neurogenesis is not well studied in global or focal cerebral ischemia. Therefore, this study aimed to investigate the role of TLR2 in adult neurogenesis after photochemically induced cerebral ischemia. At 7 days after photothrombotic ischemic injury, the number of bromodeoxyuridine (BrdU)-positive cells was increased in both TLR2 knock-out (KO) mice and wild-type (WT) mice. However, the increment rate of BrdU-positive cells was lower in TLR2 KO mice compared to that in WT mice. The number of doublecortin (DCX) and neuronal nuclei (NeuN)-positive cells in HDG was decreased after photothrombotic ischemia in TLR2 KO mice compared to that in WT mice. The survival rate of cells in HDG was decreased in TLR2 KO mice compared to that in WT mice. In contrast, the number of cleaved-caspase 3 (apoptotic marker) and the number of GFAP (glia marker)/BrdU double-positive cells in TLR2 KO mice were higher than that in WT mice. These results suggest that TLR2 can promote adult neurogenesis from neural stem cell of hippocampal dentate gyrus through increasing proliferation, differentiation, and survival from neural stem cells after ischemic injury of the brain.

  19. Activation of type 1 cannabinoid receptor (CB1R promotes neurogenesis in murine subventricular zone cell cultures.

    Directory of Open Access Journals (Sweden)

    Sara Xapelli

    Full Text Available The endocannabinoid system has been implicated in the modulation of adult neurogenesis. Here, we describe the effect of type 1 cannabinoid receptor (CB1R activation on self-renewal, proliferation and neuronal differentiation in mouse neonatal subventricular zone (SVZ stem/progenitor cell cultures. Expression of CB1R was detected in SVZ-derived immature cells (Nestin-positive, neurons and astrocytes. Stimulation of the CB1R by (R-(+-Methanandamide (R-m-AEA increased self-renewal of SVZ cells, as assessed by counting the number of secondary neurospheres and the number of Sox2+/+ cell pairs, an effect blocked by Notch pathway inhibition. Moreover, R-m-AEA treatment for 48 h, increased proliferation as assessed by BrdU incorporation assay, an effect mediated by activation of MAPK-ERK and AKT pathways. Surprisingly, stimulation of CB1R by R-m-AEA also promoted neuronal differentiation (without affecting glial differentiation, at 7 days, as shown by counting the number of NeuN-positive neurons in the cultures. Moreover, by monitoring intracellular calcium concentrations ([Ca(2+]i in single cells following KCl and histamine stimuli, a method that allows the functional evaluation of neuronal differentiation, we observed an increase in neuronal-like cells. This proneurogenic effect was blocked when SVZ cells were co-incubated with R-m-AEA and the CB1R antagonist AM 251, for 7 days, thus indicating that this effect involves CB1R activation. In accordance with an effect on neuronal differentiation and maturation, R-m-AEA also increased neurite growth, as evaluated by quantifying and measuring the number of MAP2-positive processes. Taken together, these results demonstrate that CB1R activation induces proliferation, self-renewal and neuronal differentiation from mouse neonatal SVZ cell cultures.

  20. Crosstalk between Wnt/β-catenin and estrogen receptor signaling synergistically promotes osteogenic differentiation of mesenchymal progenitor cells.

    Directory of Open Access Journals (Sweden)

    Yanhong Gao

    Full Text Available Osteogenic differentiation from mesenchymal progenitor cells (MPCs are initiated and regulated by a cascade of signaling events. Either Wnt/β-catenin or estrogen signaling pathway has been shown to play an important role in regulating skeletal development and maintaining adult tissue homeostasis. Here, we investigate the potential crosstalk and synergy of these two signaling pathways in regulating osteogenic differentiation of MPCs. We find that the activation of estrogen receptor (ER signaling by estradiol (E2 or exogenously expressed ERα in MPCs synergistically enhances Wnt3A-induced early and late osteogenic markers, as well as matrix mineralization. The E2 or ERα-mediated synergy can be effectively blocked by ERα antagonist tamoxifen. E2 stimulation can enhance endochondral ossification of Wnt3A-transduced mouse fetal limb explants. Furthermore, exogenously expressed ERα significantly enhances the maturity and mineralization of Wnt3A-induced subcutaneous and intramuscular ectopic bone formation. Mechanistically, we demonstrate that E2 does not exert any detectable effect on β-catenin/Tcf reporter activity. However, ERα expression is up-regulated within the first 48h in AdWnt3A-transduced MPCs, whereas ERβ expression is significantly inhibited within 24h. Moreover, the key enzyme for the biosynthesis of estrogens aromatase is modulated by Wnt3A in a biphasic manner, up-regulated at 24h but reduced after 48h. Our results demonstrate that, while ER signaling acts synergistically with Wnt3A in promoting osteogenic differentiation, Wnt3A may crosstalk with ER signaling by up-regulating ERα expression and down-regulating ERβ expression in MPCs. Thus, the signaling crosstalk and synergy between these two pathways should be further explored as a potential therapeutic approach to combating bone and skeletal disorders, such as fracture healing and osteoporosis.

  1. Macropinocytosis of the PDGF β-receptor promotes fibroblast transformation by H-RasG12V

    OpenAIRE

    Schmees, C.; Villaseñor, R.; Zheng, W.; Ma, H.; Zerial, M.; Heldin, C.-H.; Hellberg, C.

    2012-01-01

    Receptor tyrosine kinase (RTK) signaling is frequently increased in tumor cells, sometimes as a result of decreased receptor down-regulation. The extent to which the endocytic trafficking routes can contribute to such RTK hyperactivation is unclear. Here, we show for the first time that fibroblast transformation by H-RasG12V induces the internalization of platelet-derived growth factor β-receptor (PDGFRβ) by macropinocytosis, enhancing its signaling activity and increasing anchorage-independe...

  2. P2Y2 receptor promotes the migration and invasion of breast cancer cells via EMT-related genes Snail and E-cadherin.

    Science.gov (United States)

    Qiu, Ying; Liu, Yan; Li, Wei-Hua; Zhang, Hong-Quan; Tian, Xin-Xia; Fang, Wei-Gang

    2018-01-01

    Adenosine 5'-triphosphate (ATP) is one of the most abundant biochemical constituents within the tumor microenvironment and is postulated to play critical roles in the progression of a number of types of tumors via interaction with the P2Y2 receptor. In the present study, we demonstrated that the P2Y2 receptor was highly expressed in MCF7 and Hs578T breast cancer cells. Downregulation of the P2Y2 receptor by small interfering RNA (siRNA) significantly attenuated ATP- or UTP-driven migration and invasion of the breast cancer cells as well as expression of EMT-related genes Snail and E-cadherin. Consistent with the observations in vitro, the P2Y2 receptor was found to be abundantly expressed at the invasive edge of the tumor, in infiltrating tumor cells in breast adipose tissues and/or the cancer embolus in the lymphatic sinuses compared with the tumor core areas. Furthermore, high Snail expression and weak or negative expression of E-cadherin were observed at the invasive edge of tumors. Taken together, these data indicate that the P2Y2 receptor promoted cell migration and invasion in breast cancer cells via EMT-related genes Snail and E-cadherin.

  3. GQ-16, a Novel Peroxisome Proliferator-activated Receptor gamma (PPAR gamma) Ligand, Promotes Insulin Sensitization without Weight Gain

    NARCIS (Netherlands)

    Amato, Angelica A.; Rajagopalan, Senapathy; Lin, Jean Z.; Carvalho, Bruno M.; Figueira, Ana C. M.; Lu, Jenny; Ayers, Stephen D.; Mottin, Melina; Silveira, Rodrigo L.; Telles de Souza, Paulo; Mourao, Rosa H. V.; Saad, Mario J. A.; Togashi, Marie; Simeoni, Luiz A.; Abdalla, Dulcineia S. P.; Skaf, Munir S.; Polikparpov, Igor; Lima, Maria C. A.; Galdino, Suely L.; Brennan, Richard G.; Baxter, John D.; Pitta, Ivan R.; Webb, Paul; Phillips, Kevin J.; Neves, Francisco A. R.

    2012-01-01

    The recent discovery that peroxisome proliferator-activated receptor gamma (PPAR gamma) targeted anti-diabetic drugs function by inhibiting Cdk5-mediated phosphorylation of the receptor has provided a new viewpoint to evaluate and perhaps develop improved insulin-sensitizing agents. Herein we report

  4. Growth hormone, interferon-gamma, and leukemia inhibitory factor promoted tyrosyl phosphorylation of insulin receptor substrate-1

    DEFF Research Database (Denmark)

    Argetsinger, L S; Hsu, G W; Myers, M G

    1995-01-01

    The identification of JAK2 as a growth hormone (GH) receptor-associated, GH-activated tyrosine kinase has established tyrosyl phosphorylation as a signaling mechanism for GH. In the present study, GH is shown to stimulate tyrosyl phosphorylation of insulin receptor substrate 1 (IRS-1), the princi...... characterized insulin-like metabolic effects of GH observed in a variety of cell types....

  5. Promoter hypermethylation of the retinoic acid receptor beta2 gene is frequent in acute myeloid leukaemia and associated with the presence of CBFβ-MYH11 fusion transcripts

    DEFF Research Database (Denmark)

    Rethmeier, Anita; Aggerholm, Anni; Olesen, Lene Hyldahl

    2006-01-01

    Silencing of the putative tumour suppressor gene retinoic acid receptor beta2 (RARbeta2) caused by aberrant promoter hypermethylation has been identified in several solid tumours. In order to evaluate the extent of RARbeta2 hypermethylation and transcription in acute myeloid leukaemia (AML...... was unmethylated in 10/10 bone marrow and 7/7 blood samples from healthy individuals, the gene was hypermethylated in 43% of the AML patients. The RARbeta2 degree of promoter methylation differed between and within individuals, and the mRNA transcription levels of the gene varied inter-individually by a factor...... of 4000. A significant inverse correlation between promoter hypermethylation and gene expression could be established (t-test, P = 0.019). Comparison of methylation data with a series of other molecular alterations in the same patient materials revealed a correlation between hypermethylation...

  6. Glucocorticoids facilitate the transcription from the human cytomegalovirus major immediate early promoter in glucocorticoid receptor- and nuclear factor-I-like protein-dependent manner

    International Nuclear Information System (INIS)

    Inoue-Toyoda, Maki; Kato, Kohsuke; Nagata, Kyosuke; Yoshikawa, Hiroyuki

    2015-01-01

    Human cytomegalovirus (HCMV) is a common and usually asymptomatic virus agent in healthy individuals. Initiation of HCMV productive infection depends on expression of the major immediate early (MIE) genes. The transcription of HCMV MIE genes is regulated by a diverse set of transcription factors. It was previously reported that productive HCMV infection is triggered probably by elevation of the plasma hydroxycorticoid level. However, it is poorly understood whether the transcription of MIE genes is directly regulated by glucocorticoid. Here, we found that the dexamethasone (DEX), a synthetic glucocorticoid, facilitates the transcription of HCMV MIE genes through the MIE promoter and enhancer in a glucocorticoid receptor (GR)-dependent manner. By competitive EMSA and reporter assays, we revealed that an NF-I like protein is involved in DEX-mediated transcriptional activation of the MIE promoter. Thus, this study supports a notion that the increased level of hydroxycorticoid in the third trimester of pregnancy reactivates HCMV virus production from the latent state. - Highlights: • DEX facilitates the transcription from the HCMV MIE promoter. • GR is involved in DEX-dependent transcription from the HCMV MIE promoter. • A 17 bp repeat is responsible for the HCMV MIE promoter activation by DEX. • An NF-I-like protein is involved in the HCMV MIE promoter activation by DEX

  7. Glucocorticoids facilitate the transcription from the human cytomegalovirus major immediate early promoter in glucocorticoid receptor- and nuclear factor-I-like protein-dependent manner

    Energy Technology Data Exchange (ETDEWEB)

    Inoue-Toyoda, Maki [Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan); Kato, Kohsuke [Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan); Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan); Nagata, Kyosuke, E-mail: knagata@md.tsukuba.ac.jp [University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan); Yoshikawa, Hiroyuki [Graduate School of Comprehensive Human Sciences, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan); Faculty of Medicine, University of Tsukuba, 1-1-1 Tennodai, Tsukuba 305-8575 (Japan)

    2015-02-27

    Human cytomegalovirus (HCMV) is a common and usually asymptomatic virus agent in healthy individuals. Initiation of HCMV productive infection depends on expression of the major immediate early (MIE) genes. The transcription of HCMV MIE genes is regulated by a diverse set of transcription factors. It was previously reported that productive HCMV infection is triggered probably by elevation of the plasma hydroxycorticoid level. However, it is poorly understood whether the transcription of MIE genes is directly regulated by glucocorticoid. Here, we found that the dexamethasone (DEX), a synthetic glucocorticoid, facilitates the transcription of HCMV MIE genes through the MIE promoter and enhancer in a glucocorticoid receptor (GR)-dependent manner. By competitive EMSA and reporter assays, we revealed that an NF-I like protein is involved in DEX-mediated transcriptional activation of the MIE promoter. Thus, this study supports a notion that the increased level of hydroxycorticoid in the third trimester of pregnancy reactivates HCMV virus production from the latent state. - Highlights: • DEX facilitates the transcription from the HCMV MIE promoter. • GR is involved in DEX-dependent transcription from the HCMV MIE promoter. • A 17 bp repeat is responsible for the HCMV MIE promoter activation by DEX. • An NF-I-like protein is involved in the HCMV MIE promoter activation by DEX.

  8. Bile Acid-Mediated Sphingosine-1-Phosphate Receptor 2 Signaling Promotes Neuroinflammation during Hepatic Encephalopathy in Mice

    Directory of Open Access Journals (Sweden)

    Matthew McMillin

    2017-07-01

    Full Text Available Hepatic encephalopathy (HE is a neuropsychiatric complication that occurs due to deteriorating hepatic function and this syndrome influences patient quality of life, clinical management strategies and survival. During acute liver failure, circulating bile acids increase due to a disruption of the enterohepatic circulation. We previously identified that bile acid-mediated signaling occurs in the brain during HE and contributes to cognitive impairment. However, the influences of bile acids and their downstream signaling pathways on HE-induced neuroinflammation have not been assessed. Conjugated bile acids, such as taurocholic acid (TCA, can activate sphingosine-1-phosphate receptor 2 (S1PR2, which has been shown to promote immune cell infiltration and inflammation in other models. The current study aimed to assess the role of bile-acid mediated S1PR2 signaling in neuroinflammation and disease progression during azoxymethane (AOM-induced HE in mice. Our findings demonstrate a temporal increase of bile acids in the cortex during AOM-induced HE and identified that cortical bile acids were elevated as an early event in this model. In order to classify the specific bile acids that were elevated during HE, a metabolic screen was performed and this assay identified that TCA was increased in the serum and cortex during AOM-induced HE. To reduce bile acid concentrations in the brain, mice were fed a diet supplemented with cholestyramine, which alleviated neuroinflammation by reducing proinflammatory cytokine expression in the cortex compared to the control diet-fed AOM-treated mice. S1PR2 was expressed primarily in neurons and TCA treatment increased chemokine ligand 2 mRNA expression in these cells. The infusion of JTE-013, a S1PR2 antagonist, into the lateral ventricle prior to AOM injection protected against neurological decline and reduced neuroinflammation compared to DMSO-infused AOM-treated mice. Together, this identifies that reducing bile acid

  9. Potentiation of amygdala AMPA receptor activity selectively promotes escalated alcohol self-administration in a CaMKII-dependent manner.

    Science.gov (United States)

    Cannady, Reginald; Fisher, Kristen R; Graham, Caitlin; Crayle, Jesse; Besheer, Joyce; Hodge, Clyde W

    2017-05-01

    Growing evidence indicates that drugs of abuse gain control over the individual by usurping glutamate-linked mechanisms of neuroplasticity in reward-related brain regions. Accordingly, we have shown that glutamate α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor (AMPAR) activity in the amygdala is required for the positive reinforcing effects of alcohol, which underlie the initial stages of addiction. It is unknown, however, if enhanced AMPAR activity in the amygdala facilitates alcohol self-administration, which is a kernel premise of glutamate hypotheses of addiction. Here, we show that low-dose alcohol (0.6 g/kg/30 minutes) self-administration increases phosphorylation (activation) of AMPAR subtype GluA1 S831 (pGluA1 S831) in the central amygdala (CeA), basolateral amygdala and nucleus accumbens core (AcbC) of selectively bred alcohol-preferring P-rats as compared with behavior-matched (non-drug) sucrose controls. The functional role of enhanced AMPAR activity was assessed via site-specific infusion of the AMPAR positive modulator, aniracetam, in the CeA and AcbC prior to alcohol self-administration. Intra-CeA aniracetam increased alcohol-reinforced but not sucrose-reinforced responding and was ineffective following intra-AcbC infusion. Because GluA1 S831 is a Ca2+/calmodulin-dependent protein kinase II (CaMKII) substrate, we sought to determine if AMPAR regulation of enhanced alcohol self-administration is dependent on CaMKII activity. Intra-CeA infusion of the cell-permeable CaMKII peptide inhibitor myristolated autocamtide-2-related inhibitory peptide (m-AIP) dose-dependently reduced alcohol self-administration. A subthreshold dose of m-AIP also blocked the aniracetam-induced escalation of alcohol self-administration, demonstrating that AMPAR-mediated potentiation of alcohol reinforcement requires CaMKII activity in the amygdala. Enhanced activity of plasticity-linked AMPAR-CaMKII signaling in the amygdala may promote escalated alcohol use

  10. Local angiotensin II promotes adipogenic differentiation of human adipose tissue mesenchymal stem cells through type 2 angiotensin receptor

    Directory of Open Access Journals (Sweden)

    Veronika Y. Sysoeva

    2017-12-01

    Full Text Available Obesity is often associated with high systemic and local activity of renin-angiotensin system (RAS. Mesenchymal stem cells of adipose tissue are the main source of adipocytes. The aim of this study was to clarify how local RAS could control adipose differentiation of human adipose tissue derived mesenchymal stem cells (ADSCs. We examined the distribution of angiotensin receptor expressing cells in human adipose tissue and found that type 1 and type 2 receptors are co-expressed in its stromal compartment, which is known to contain mesenchymal stem cells. To study the expression of receptors specifically in ADSCs we have isolated them from adipose tissue. Up to 99% of cultured ADSCs expressed angiotensin II (AngII receptor type 1 (AT1. Using the analysis of Ca2+ mobilization in single cells we found that only 5.2 ± 2.7% of ADSCs specifically respond to serial Ang II applications via AT1 receptor and expressed this receptor constantly. This AT1const ADSCs subpopulation exhibited increased adipose competency, which was triggered by endogenous AngII. Inhibitory and expression analyses showed that AT1const ADSCs highly co-express AngII type 2 receptor (AT2, which was responsible for increased adipose competency of this ADSC subpopulation.

  11. L-type Ca2+ channel blockers promote Ca2+ accumulation when dopamine receptors are activated in striatal neurons

    OpenAIRE

    Eaton, Molly E.; Macías, Wendy; Youngs, Rachael M.; Rajadhyaksha, Anjali; Dudman, Joshua T.; Konradi, Christine

    2004-01-01

    Dopamine (DA) receptor-mediated signal transduction and gene expression play a central role in many brain disorders from schizophrenia to Parkinson’s disease to addiction. While trying to evaluate the role of L-type Ca2+ channels in dopamine D1 receptor-mediated phosphorylation of the transcription factor cyclic AMP response element-binding protein (CREB), we found that activation of dopamine D1 receptors alters the properties of L-type Ca2+ channel inhibitors and turns them into facilitators...

  12. Changes in lymphocyte glucocorticoid and beta-adrenergic receptors in veal calves treated with clenbuterol and steroid hormones for growth-promoting purposes.

    Science.gov (United States)

    Odore, R; Badino, P; Pagliasso, S; Nebbia, C; Cuniberti, B; Barbero, R; Re, G

    2006-04-01

    In order to identify possible peripheral markers of illegal treatments with growth-promoting agents in veal calves, beta-adrenergic receptor (beta-AR) and glucocorticoid receptor (GR) concentrations were measured in lymphocytes of 12 male Friesian crossbred calves (six controls and six treated). The animals received a cocktail of anabolic and re-partitioning agents [17beta-oestradiol: 3 x 10 mg intramuscular (i.m.) doses at 17-day intervals; dexamethasone sodium phosphate: 4 mg/day for 6 days and 5 mg/day for six further days dissolved in milk; and clenbuterol: 20 microg/kg/day dissolved in milk for the last 40 days before slaughter]. Blood samples were collected by venipuncture at different time points and lymphocytes were isolated by density gradient centrifugation. Lymphocyte beta-AR and GR levels were measured by binding assays. Treatment with re-partitioning agents caused a significant down-regulation of lymphocyte beta-ARs 19 days after the beginning of clenbuterol administration and at day 55 (after dexamethasone withdrawal, just before slaughter). This phenomenon was partially reversed at day 50, after dexamethasone administration, at which time a significant decrease in GR concentrations also occurred. For both types of receptors, no significant changes in the dissociation constant values were observed at any time point. Lymphocytes express measurable concentrations of beta-ARs and GRs and the measurement of receptor levels highlights the fluctuation of receptor expression due to the dynamic interaction of the drugs used in combination. Lymphocyte receptor determination could therefore be included in a battery of biological assays to detect illegal treatments with anabolic agents in veal calves in the light of a multivariate approach.

  13. Overexpression of the E2F target gene CENPI promotes chromosome instability and predicts poor prognosis in estrogen receptor-positive breast cancer.

    Science.gov (United States)

    Thangavelu, Pulari U; Lin, Cheng-Yu; Vaidyanathan, Srividya; Nguyen, Thu H M; Dray, Eloise; Duijf, Pascal H G

    2017-09-22

    During cell division, chromosome segregation is facilitated by the mitotic checkpoint, or spindle assembly checkpoint (SAC), which ensures correct kinetochore-microtubule attachments and prevents premature sister-chromatid separation. It is well established that misexpression of SAC components on the outer kinetochores promotes chromosome instability (CIN) and tumorigenesis. Here, we study the expression of CENP-I, a key component of the HIKM complex at the inner kinetochores, in breast cancer, including ductal, lobular, medullary and male breast carcinomas. CENPI mRNA and protein levels are significantly elevated in estrogen receptor-positive (ER+) but not in estrogen receptor-negative (ER-) breast carcinoma. Well-established prognostic tests indicate that CENPI overexpression constitutes a powerful independent marker for poor patient prognosis and survival in ER+ breast cancer. We further demonstrate that CENPI is an E2F target gene. Consistently, it is overexpressed in RB1 -deficient breast cancers. However, CENP-I overexpression is not purely due to cell cycle-associated expression. In ER+ breast cancer cells, CENP-I overexpression promotes CIN, especially chromosome gains. In addition, in ER+ breast carcinomas the degree of CENPI overexpression is proportional to the level of aneuploidy and CENPI overexpression is one of the strongest markers for CIN identified to date. Our results indicate that overexpression of the inner kinetochore protein CENP-I promotes CIN and forecasts poor prognosis for ER+ breast cancer patients. These observations provide novel mechanistic insights and have important implications for breast cancer diagnostics and potentially therapeutic targeting.

  14. Constitutively active erythropoietin receptor expression in breast cancer cells promotes cellular proliferation and migration through a MAP-kinase dependent pathway

    International Nuclear Information System (INIS)

    Fu Ping; Jiang Xiaohong; Arcasoy, Murat O.

    2009-01-01

    The role of erythropoietin receptor (EpoR) expression in tumor cells and the potential of EpoR-mediated signaling to contribute to cellular proliferation and invasiveness require further characterization. To determine whether EpoR expression and activation in tumor cells modulates intracellular signal transduction to promote cellular proliferation and migration, we employed a novel experimental model using human breast cancer cells engineered to stably express a constitutively active EpoR-R129C variant. EpoR-R129C expression resulted in increased cellular proliferation and migration of breast cancer cells and these effects were associated with significantly increased Epo-induced phosphorylation of ERK1/2, AKT and c-Jun-NH2-kinase (SAPK/JNK) proteins. Expression of the constitutively active EpoR-R129C receptor promoted the proliferation and migration of breast cancer cells via activation of ERK- and SAPK/JNK-dependent signaling pathways, respectively. These findings suggest that EpoR over-expression and activation in breast cancer cells has the potential to contribute to tumor progression by promoting the proliferation and invasiveness of the neoplastic cells.

  15. Activation of type 2 cannabinoid receptors (CB2R) promotes fatty acid oxidation through the SIRT1/PGC-1α pathway

    Energy Technology Data Exchange (ETDEWEB)

    Zheng, Xuqin [Department of Endocrinology, First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province 210029 (China); Sun, Tao [Department of Neurology, Jinling Hospital, Nanjing University School of Medicine, Nanjing, Jiangsu Province 210002 (China); Wang, Xiaodong, E-mail: xdwang666@hotmail.com [Department of Endocrinology, First Affiliated Hospital, Nanjing Medical University, Nanjing, Jiangsu Province 210029 (China)

    2013-07-05

    Highlights: •TC, a CB2R specific agonist, stimulates SIRT1 activity by PKA/CREB pathway. •TC promotes PGC-1α transcriptional activity by increasing its deacetylation. •TC increases the expression of genes linked to FAO and promotes the rate of FAO. •The effects of TC in FAO are dependent on CB2R. •Suggesting CB2R as a target to treat diseases with lipid dysregulation. -- Abstract: Abnormal fatty acid oxidation has been associated with obesity and type 2 diabetes. At the transcriptional level, peroxisome proliferator-activated receptor-gamma coactivator 1α (PGC-1α) has been reported to strongly increase the ability of hormone nuclear receptors PPARα and ERRα to drive transcription of fatty acid oxidation enzymes. In this study, we report that a specific agonist of the type 2 cannabinoid receptor (CB2R) can lead to fatty acid oxidation through the PGC-1α pathway. We have found that CB2R is expressed in differentiated C2C12 myotubes, and that use of the specific agonist trans-caryophyllene (TC) stimulates sirtuin 1 (SIRT1) deacetylase activity by increasing the phosphorylation of cAMP response element-binding protein (CREB), thus leading to increased levels of PGC-1α deacetylation. This use of TC treatment increases the expression of genes linked to the fatty acid oxidation pathway in a SIRT1/PGC-1α-dependent mechanism and also drastically accelerates the rate of complete fatty acid oxidation in C2C12 myotubes, neither of which occur when CB2R mRNA is knocked down using siRNA. These results reveal that activation of CB2R by a selective agonist promotes lipid oxidation through a signaling/transcriptional pathway. Our findings imply that pharmacological manipulation of CB2R may provide therapeutic possibilities to treat metabolic diseases associated with lipid dysregulation.

  16. Androgen receptor regulated microRNA miR-182-5p promotes prostate cancer progression by targeting the ARRDC3/ITGB4 pathway

    International Nuclear Information System (INIS)

    Yao, Jingjing; Xu, Chen; Fang, Ziyu; Li, Yaoming; Liu, Houqi; Wang, Yue; Xu, Chuanliang; Sun, Yinghao

    2016-01-01

    Abstracts: MicroRNAs (miRNAs) are important endogenous gene regulators that play key roles in prostate cancer development and metastasis. However, specific miRNA expression patterns in prostate cancer tissues from Chinese patients remain largely unknown. In this study, we compared miRNA expression patterns in 65 pairs of prostate cancer and para-cancer tissues by RNA sequencing and found that miR-182-5p was the most up-regulated miRNA in prostate cancer tissues. The result was validated using realtime PCR in 18 pairs of prostate cancer and para-cancer tissues. In in vitro analysis, it was confirmed that miR-182-5p promotes prostate cancer cell proliferation, invasion and migration and inhibit apoptosis. In addition, the androgen receptor directly regulated the transcription of miR-182-5p, which could target to the 3′UTR of ARRDC3 mRNA and affect the expression of ARRDC3 and its downstream gene ITGB4. For the in vivo experiment, miR-182-5p overexpression also promoted the growth and progression of prostate cancer tumors. In this regard, we suggest that miR-182-5p may be a key androgen receptor-regulated factor that contributes to the development and metastasis of Chinese prostate cancers and may be a potential target for the early diagnosis and therapeutic studies of prostate cancer. -- Highlights: •miR-182-5p is the mostly up-regulated miRNA in Chinese prostate cancer. •miR-182-5p is regulated by androgen receptor. •miR-182-5p promotes prostate cancer progression. •miR-182-5p regulates ARRDC3/ITGB4 pathway.

  17. Androgen receptor regulated microRNA miR-182-5p promotes prostate cancer progression by targeting the ARRDC3/ITGB4 pathway

    Energy Technology Data Exchange (ETDEWEB)

    Yao, Jingjing [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China); Xu, Chen [Research Center of Developmental Biology, Second Military Medical University, 800th Xiangyin Road, Shanghai, 200433 (China); Department of Orthopedics, Changzheng Hospital Affiliated to Second Military Medical University, 415th Feng Yang Road, Shanghai, 200003 (China); Fang, Ziyu; Li, Yaoming [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China); Liu, Houqi; Wang, Yue [Research Center of Developmental Biology, Second Military Medical University, 800th Xiangyin Road, Shanghai, 200433 (China); Translational Medicine Center, Second Military Medical University, 800th Xiangyin Road, Shanghai, 200433 (China); Xu, Chuanliang [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China); Sun, Yinghao, E-mail: sunyh@medmail.com.cn [Department of Urology, Shanghai Changhai Hospital, Second Military Medical University, Shanghai, 200433 (China)

    2016-05-20

    Abstracts: MicroRNAs (miRNAs) are important endogenous gene regulators that play key roles in prostate cancer development and metastasis. However, specific miRNA expression patterns in prostate cancer tissues from Chinese patients remain largely unknown. In this study, we compared miRNA expression patterns in 65 pairs of prostate cancer and para-cancer tissues by RNA sequencing and found that miR-182-5p was the most up-regulated miRNA in prostate cancer tissues. The result was validated using realtime PCR in 18 pairs of prostate cancer and para-cancer tissues. In in vitro analysis, it was confirmed that miR-182-5p promotes prostate cancer cell proliferation, invasion and migration and inhibit apoptosis. In addition, the androgen receptor directly regulated the transcription of miR-182-5p, which could target to the 3′UTR of ARRDC3 mRNA and affect the expression of ARRDC3 and its downstream gene ITGB4. For the in vivo experiment, miR-182-5p overexpression also promoted the growth and progression of prostate cancer tumors. In this regard, we suggest that miR-182-5p may be a key androgen receptor-regulated factor that contributes to the development and metastasis of Chinese prostate cancers and may be a potential target for the early diagnosis and therapeutic studies of prostate cancer. -- Highlights: •miR-182-5p is the mostly up-regulated miRNA in Chinese prostate cancer. •miR-182-5p is regulated by androgen receptor. •miR-182-5p promotes prostate cancer progression. •miR-182-5p regulates ARRDC3/ITGB4 pathway.

  18. The CytR repressor antagonizes cyclic AMP-cyclic AMP receptor protein activation of the deoCp2 promoter of Escherichia coli K-12

    DEFF Research Database (Denmark)

    Søgaard-Andersen, Lotte; Martinussen, J; Møllegaard, N E

    1990-01-01

    We have investigated the regulation of the Escherichia coli deoCp2 promoter by the CytR repressor and the cyclic AMP (cAMP) receptor protein (CRP) complexed to cAMP. Promoter regions controlled by these two proteins characteristically contain tandem cAMP-CRP binding sites. Here we show that (i) Cyt......R selectively regulated cAMP-CRP-dependent initiations, although transcription started from the same site in deoCp2 in the absence or presence of cAMP-CRP; (ii) deletion of the uppermost cAMP-CRP target (CRP-2) resulted in loss of CytR regulation, but had only a minor effect on positive control by the cAMP...

  19. Acute alertness-promoting effects of a novel histamine subtype-3 receptor inverse agonist in healthy sleep-deprived male volunteers.

    Science.gov (United States)

    Iannone, R; Palcza, J; Renger, J J; Calder, N; Cerchio, K; Gottesdiener, K; Hargreaves, R; Dijk, D J; Boyle, J; Murphy, M G

    2010-12-01

    The alertness-promoting effect of MK-0249 (10 or 50 mg), a histamine subtype-3 receptor (HRH3) inverse agonist (IA), was evaluated in the stimulant reference sleep deprivation model (SRSDM) using a double-blind, double-dummy, placebo- and modafinil- (200 mg) controlled, four-period crossover design in 24 healthy young men. The two primary hypotheses were related to sleep latency (first appearance of one epoch of stage 2, 3, or 4 or REM sleep, as detected using polysomnography (PSG)) at 8:00 AM on day 2. Statistically significant increases in sleep latency were observed in association with the use of modafinil 200 mg (9.07 min; P Sleep latency was higher when averaged over all MWT time points (P modafinil and for both doses of MK-0249). The alertness-promoting effect with the use of MK-0249 in the SRSDM suggests that HRH3 IAs may be effective in disorders involving excessive somnolence.

  20. Antigen-affinity controls pregerminal centser B cell selection by promoting Mcl-1 induction through BAFF receptor signaling

    NARCIS (Netherlands)

    Wensveen, Felix M.; Slinger, Erik; van Attekum, Martijn H. A.; Brink, Robert; Eldering, Eric

    2016-01-01

    Upon antigen encounter, the responsive B cell pool undergoes stringent selection which eliminates cells with low B cell receptor (BCR) affinity. Already before formation of the germinal center, activated B cells of low-affinity are negatively selected in a process that is molecularly not well

  1. Antagonism of serotonin receptor 1B decreases viability and promotes apoptosis in the COS canine osteosarcoma cell line.

    Science.gov (United States)

    Viall, A K; Goodall, C P; Stang, B; Marley, K; Chappell, P E; Bracha, S

    2016-06-01

    Serotonin receptor 1B (5HTR1B) traditionally exhibits anti-proliferative activity in osteoblasts. We examined the expression and function of 5HTR1B in the COS canine osteosarcoma cell line and normal canine osteoblasts. Equal levels of 5HTR1B gene and protein expression were found between normal and malignant osteoblasts. Treatment with serotonin enhanced viability of osteosarcoma cells but not normal osteoblasts. Challenge with the 5HTR1B agonist anpirtoline caused no change in cell viability. Rather incubation with the specific receptor antagonist SB224289 caused reduction in osteoblast viability, with this effect more substantial in osteosarcoma cells. Investigation of this inhibitory activity showed 5HTR1B antagonism induces apoptosis in malignant cells. Evaluation of phosphorylated levels of CREB and ERK, transcriptional regulators associated with serotonin receptor signalling in osteoblasts, revealed aberrant 5HTR1B signalling in COS. Our results confirm the presence of 5HTR1B in a canine osteosarcoma cell line and highlight this receptor as a possible novel therapeutic target. © 2014 John Wiley & Sons Ltd.

  2. Molecular cloning and functional characterization of the human platelet-derived growth factor alpha receptor gene promoter

    NARCIS (Netherlands)

    Afink, G. B.; Nistér, M.; Stassen, B. H.; Joosten, P. H.; Rademakers, P. J.; Bongcam-Rudloff, E.; van Zoelen, E. J.; Mosselman, S.

    1995-01-01

    Expression of the platelet-derived growth factor alpha receptor (PDGF alpha R) is strictly regulated during mammalian development and tumorigenesis. The molecular mechanisms involved in the specific regulation of PDGF alpha R expression are unknown, but transcriptional regulation of the PDGF alpha R

  3. Hypermethylation of E-Cadherin and Estrogen Receptor-a Gene Promoter and Its Association with Clinicopathological Features of Breast Cancer in Iranian Patients

    Directory of Open Access Journals (Sweden)

    Mozhgan Rasti

    2009-06-01

    Full Text Available Background: Aberrant methylation of cytosine-guanine dinucleotideislands leads to inactivation of tumor suppressorgenes in breast cancer. Tumor suppressor genes are unmethylatedin normal tissue and often become hypermethylatedduring tumor formation, leading to gene silencing. We investigatedthe association between E-cadherin (CDH1 and estrogenreceptor-α (ESRα gene promoter methylation andmajor clinical and pathological features of breast cancer inIranian women.Methods: DNA was extracted from 67 primary breast tumorsand gene promoter methylation was analyzed by methylationspecificpolymerase chain reaction method.Results: Fifty percent of the samples showed aberrant methylationin at least one of the two tested loci. We detectedCDH1 hypermethylation in 41% of invasive tumors and receptor-α gene hypermethylation in 18% of invasive tumorsamples. We found no association between CDH1 and receptor-α gene hypermethylation (P=0.45. There was a correlationbetween hypermethylation of CDH1 locus and tumorsize ≥5 cm (P=0.019.Conclusion: Our data suggest that the malignant progressionof human ductal and lobular breast carcinoma in Iranianwomen involves a heterogeneous pattern of cytosine-guaninedinucleotide island hypermethylation of the CDH1 gene.

  4. Genetic deletion of paired immunoglobulin-like receptor B does not promote axonal plasticity or functional recovery after traumatic brain injury.

    Science.gov (United States)

    Omoto, Shusaku; Ueno, Masaki; Mochio, Soichiro; Takai, Toshiyuki; Yamashita, Toshihide

    2010-09-29

    The rewiring of neural networks is a fundamental step in recovering behavioral functions after brain injury. However, there is limited potential for axonal plasticity in the adult CNS. The myelin-associated proteins Nogo, myelin-associated glycoprotein (MAG), and oligodendrocyte myelin glycoprotein (OMgp) are known to inhibit axonal plasticity, and thus targeting the inhibitory pathways they participate in is a potential means of promoting plasticity and functional recovery. Each of Nogo, MAG, and OMgp interacts with both the Nogo receptor (NgR) and paired immunoglobulin-like receptor B (PirB). Here, we determined whether blocking PirB activity enhances axonal reorganization and functional recovery after cortical injury. We found that axons of the contralesional corticospinal tract sprouted into the denervated side of the cervical spinal cord after unilateral injury of the motor cortex. The extent to which this axonal reorganization occurred was far greater in mice lesioned during early postnatal days than in mice lesioned at an age when myelin had begun to form. This suggests that myelin-associated proteins might limit axonal remodeling in vivo. However, the number of sprouting fibers within either the corticospinal or corticorubral tract was not enhanced in PirB(-/-) mice. Blocking PirB signaling also failed to enhance functional recovery with three motor tests. Our results suggest that blocking the function of PirB is not sufficient to promote axonal reorganization or functional recovery after cortical injury.

  5. Fiber mediated receptor masking in non-infected bystander cells restricts adenovirus cell killing effect but promotes adenovirus host co-existence.

    Directory of Open Access Journals (Sweden)

    Johan Rebetz

    Full Text Available The basic concept of conditionally replicating adenoviruses (CRAD as oncolytic agents is that progenies generated from each round of infection will disperse, infect and kill new cancer cells. However, CRAD has only inhibited, but not eradicated tumor growth in xenograft tumor therapy, and CRAD therapy has had only marginal clinical benefit to cancer patients. Here, we found that CRAD propagation and cancer cell survival co-existed for long periods of time when infection was initiated at low multiplicity of infection (MOI, and cancer cell killing was inefficient and slow compared to the assumed cell killing effect upon infection at high MOI. Excessive production of fiber molecules from initial CRAD infection of only 1 to 2% cancer cells and their release prior to the viral particle itself caused a tropism-specific receptor masking in both infected and non-infected bystander cells. Consequently, the non-infected bystander cells were inefficiently bound and infected by CRAD progenies. Further, fiber overproduction with concomitant restriction of adenovirus spread was observed in xenograft cancer therapy models. Besides the CAR-binding Ad4, Ad5, and Ad37, infection with CD46-binding Ad35 and Ad11 also caused receptor masking. Fiber overproduction and its resulting receptor masking thus play a key role in limiting CRAD functionality, but potentially promote adenovirus and host cell co-existence. These findings also give important clues for understanding mechanisms underlying the natural infection course of various adenoviruses.

  6. Carbetocin is a Functional Selective Gq Agonist That Does Not Promote Oxytocin Receptor Recycling After Inducing β-Arrestin-Independent Internalisation.

    Science.gov (United States)

    Passoni, I; Leonzino, M; Gigliucci, V; Chini, B; Busnelli, M

    2016-04-01

    Carbetocin, a long-acting oxytocin analogue, has been reported to elicit interesting and peculiar behavioural effects. The present study investigated the molecular pharmacology of carbetocin, aiming to better understand the molecular basis of its action in the brain. Using bioluminescence resonance energy transfer biosensors, we characterised the effects of carbetocin on the three human oxytocin/vasopressin receptors expressed in the nervous system: the oxytocin receptor (OXTR) and the vasopressin V1a (V1aR) and V1b (V1bR) receptors. Our results indicate that (i) carbetocin activates the OXTR but not the V1aR and V1bR at which it may act as an antagonist; (ii) carbetocin selectively activates only the OXTR/Gq pathway displaying a strong functional selectivity; (iii) carbetocin is a partial agonist at the OXTR/Gq coupling; (iv) carbetocin promotes OXTR internalisation via a previously unreported β-arrestin-independent pathway; and (v) carbetocin does not induce OXTR recycling to the plasma membrane. Altogether, these molecular pharmacology features identify carbetocin as a substantially different analogue compared to the endogenous oxytocin and, consequently, carbetocin is not expected to mimic oxytocin in the brain. Whether these unique features of carbetocin could be exploited therapeutically remains to be established. © 2016 The Authors. Journal of Neuroendocrinology published by John Wiley & Sons Ltd on behalf of British Society for Neuroendocrinology.

  7. Apolipoprotein M regulates the orphan nuclear receptor LRH-1 gene expression through binding to its promoter region in HepG2 cells

    Directory of Open Access Journals (Sweden)

    Pan Y

    2015-04-01

    Full Text Available Yi Pan,1,2,* Hou-gang Zhou,1,* Hui Zhou,3 Min Hu,1 Li-jun Tang2 1Clinical Laboratory, The Second Xiangya Hospital of Central South University, Changsha, Hunan, People’s Republic of China; 2Molecular Biology Research Center, School of Life Sciences, Central South University, Changsha, Hunan, People’s Republic of China; 3Tumor Hospital of Xiangya School of Medicine, Central South University, Changsha, Hunan, People’s Republic of China *These authors contributed equally to this work Abstract: Apolipoprotein M (ApoM is predominantly located in the high-density lipoprotein in human plasma. It has been demonstrated that ApoM expression could be regulated by several crucial nuclear receptors that are involved in the bile acid metabolism. In the present study, by combining gene-silencing experiments, overexpression studies, and chromatin immunoprecipitation assays, we showed that ApoM positively regulated liver receptor homolog-1 (LRH-1 gene expression via direct binding to an LRH-1 promoter region (nucleotides -406/-197. In addition, we investigated the effects of farnesoid X receptor agonist GW4064 on hepatic ApoM expression in vitro. In HepG2 cell cultures, both mRNA and protein levels of ApoM and LRH-1 were decreased in a time-dependent manner in the presence of 1 µM GW4064, and the inhibition effect was gradually attenuated after 24 hours. In conclusion, our findings present supportive evidence that ApoM is a regulator of human LRH-1 transcription, and further reveal the importance of ApoM as a critical regulator of bile acids metabolism. Keywords: bile acids, chromatin immunoprecipitation assay, farnesoid X receptor, GW4064, high-density lipoprotein 

  8. Biogenesis of the mitochondrial TOM complex: Mim1 promotes insertion and assembly of signal-anchored receptors.

    Science.gov (United States)

    Becker, Thomas; Pfannschmidt, Sylvia; Guiard, Bernard; Stojanovski, Diana; Milenkovic, Dusanka; Kutik, Stephan; Pfanner, Nikolaus; Meisinger, Chris; Wiedemann, Nils

    2008-01-04

    The translocase of the outer membrane (TOM complex) is the central entry gate for nuclear-encoded mitochondrial precursor proteins. All Tom proteins are also encoded by nuclear genes and synthesized as precursors in the cytosol. The channel-forming beta-barrel protein Tom40 is targeted to mitochondria via Tom receptors and inserted into the outer membrane by the sorting and assembly machinery (SAM complex). A further outer membrane protein, Mim1, plays a less defined role in assembly of Tom40 into the TOM complex. The three receptors Tom20, Tom22, and Tom70 are anchored in the outer membrane by a single transmembrane alpha-helix, located at the N terminus in the case of Tom20 and Tom70 (signal-anchored) or in the C-terminal portion in the case of Tom22 (tail-anchored). Insertion of the precursor of Tom22 into the outer membrane requires pre-existing Tom receptors while the import pathway of the precursors of Tom20 and Tom70 is only poorly understood. We report that Mim1 is required for efficient membrane insertion and assembly of Tom20 and Tom70, but not Tom22. We show that Mim1 associates with SAM(core) components to a large SAM complex, explaining its role in late steps of the assembly pathway of Tom40. We conclude that Mim1 is not only required for biogenesis of the beta-barrel protein Tom40 but also for membrane insertion and assembly of signal-anchored Tom receptors. Thus, Mim1 plays an important role in the efficient assembly of the mitochondrial TOM complex.

  9. The Receptor Guanylyl Cyclase Type D (GC-D) Ligand Uroguanylin Promotes the Acquisition of Food Preferences in Mice

    OpenAIRE

    Arakawa, Hiroyuki; Kelliher, Kevin R.; Zufall, Frank; Munger, Steven D.

    2013-01-01

    Rodents rely on olfactory stimuli to communicate information between conspecifics that is critical for health and survival. For example, rodents that detect a food odor simultaneously with the social odor carbon disulfide (CS2) will acquire a preference for that food. Disruption of the chemosensory transduction cascade in CS2-sensitive olfactory sensory neurons (OSNs) that express the receptor guanylyl cyclase type D (GC-D; GC-D+ OSNs) will prevent mice from acquiring these preferences. GC-D+...

  10. Glucagon Receptor Antagonism Improves Glucose Metabolism and Cardiac Function by Promoting AMP-Mediated Protein Kinase in Diabetic Mice

    Directory of Open Access Journals (Sweden)

    Ankit X. Sharma

    2018-02-01

    Full Text Available The antidiabetic potential of glucagon receptor antagonism presents an opportunity for use in an insulin-centric clinical environment. To investigate the metabolic effects of glucagon receptor antagonism in type 2 diabetes, we treated Leprdb/db and Lepob/ob mice with REMD 2.59, a human monoclonal antibody and competitive antagonist of the glucagon receptor. As expected, REMD 2.59 suppresses hepatic glucose production and improves glycemia. Surprisingly, it also enhances insulin action in both liver and skeletal muscle, coinciding with an increase in AMP-activated protein kinase (AMPK-mediated lipid oxidation. Furthermore, weekly REMD 2.59 treatment over a period of months protects against diabetic cardiomyopathy. These functional improvements are not derived simply from correcting the systemic milieu; nondiabetic mice with cardiac-specific overexpression of lipoprotein lipase also show improvements in contractile function after REMD 2.59 treatment. These observations suggest that hyperglucagonemia enables lipotoxic conditions, allowing the development of insulin resistance and cardiac dysfunction during disease progression.

  11. Ceramide 1-phosphate (C1P) promotes cell migration Involvement of a specific C1P receptor.

    Science.gov (United States)

    Granado, María H; Gangoiti, Patricia; Ouro, Alberto; Arana, Lide; González, Monika; Trueba, Miguel; Gómez-Muñoz, Antonio

    2009-03-01

    Ceramide 1-phosphate (C1P) is a bioactive sphingolipid that is implicated in the regulation of cell homeostasis and the control of inflammation. It is mitogenic for fibroblasts and macrophages, and has been described as potent inhibitor of apoptosis. Using RAW 264.7 macrophages we have now discovered a new biological activity of C1P: stimulation of cell migration. This novel action can only be observed when C1P is applied exogenously to the cells in culture, and not by increasing the intracellular levels of C1P. This fact led to identify a specific receptor through which C1P stimulates cell migration. The receptor is coupled to G(i) proteins and causes phosphorylation of extracellularly regulated kinases 1 and 2, and protein kinase B (also known as Akt) upon ligation with C1P. Inhibition of either of these pathways completely abolished C1P-stimulated macrophage migration. In addition, C1P stimulated the DNA binding activity of nuclear factor kappa B, and blockade of this transcription factor resulted in complete inhibition of macrophage migration. This newly identified receptor could be an important drug target for treatment of illnesses that are associated to inflammatory processes, or to diseases in which cell migration is a major cause of pathology, as it occurs in metastatic tumors.

  12. TRIM32 promotes retinoic acid receptor α-mediated differentiation in human promyelogenous leukemic cell line HL60

    International Nuclear Information System (INIS)

    Sato, Tomonobu; Okumura, Fumihiko; Iguchi, Akihiro; Ariga, Tadashi; Hatakeyama, Shigetsugu

    2012-01-01

    Highlights: ► TRIM32 enhanced RARα-mediated transcriptional activity even in the absence of RA. ► TRIM32 stabilized RARα in the human promyelogenous leukemic cell line HL60. ► Overexpression of TRIM32 in HL60 cells induced granulocytic differentiation. ► TRIM32 may function as a coactivator for RARα-mediated transcription in APL cells. -- Abstract: Ubiquitination, one of the posttranslational modifications, appears to be involved in the transcriptional activity of nuclear receptors including retinoic acid receptor α (RARα). We previously reported that an E3 ubiquitin ligase, TRIM32, interacts with several important proteins including RARα and enhances transcriptional activity of RARα in mouse neuroblastoma cells and embryonal carcinoma cells. Retinoic acid (RA), which acts as a ligand to nuclear receptors including RARα, plays crucial roles in development, differentiation, cell cycles and apoptosis. In this study, we found that TRIM32 enhances RARα-mediated transcriptional activity even in the absence of RA and stabilizes RARα in the human promyelogenous leukemic cell line HL60. Moreover, we found that overexpression of TRIM32 in HL60 cells suppresses cellular proliferation and induces granulocytic differentiation even in the absence of RA. These findings suggest that TRIM32 functions as one of the coactivators for RARα-mediated transcription in acute promyelogenous leukemia (APL) cells, and thus TRIM32 may become a potentially therapeutic target for APL.

  13. Estrogen modulates NFκB signaling by enhancing IκBα levels and blocking p65 binding at the promoters of inflammatory genes via estrogen receptor-β.

    Directory of Open Access Journals (Sweden)

    Dongqi Xing

    Full Text Available NFκB signaling is critical for expression of genes involved in the vascular injury response. We have shown that estrogen (17β-estradiol, E2 inhibits expression of these genes in an estrogen receptor (ER-dependent manner in injured rat carotid arteries and in tumor necrosis factor (TNF-α treated rat aortic smooth muscle cells (RASMCs. This study tested whether E2 inhibits NFκB signaling in RASMCs and defined the mechanisms.TNF-α treated RASMCs demonstrated rapid degradation of IκBα (10-30 min, followed by dramatic increases in IκBα mRNA and protein synthesis (40-60 min. E2 enhanced TNF-α induced IκBα synthesis without affecting IκBα degradation. Chromatin immunoprecipitation (ChIP assays revealed that E2 pretreatment both enhanced TNF-α induced binding of NFκB p65 to the IκBα promoter and suppressed TNF-α induced binding of NFκB p65 to and reduced the levels of acetylated histone 3 at promoters of monocyte chemotactic protein (MCP-1 and cytokine-induced neutrophil chemoattractant (CINC-2β genes. ChIP analyses also demonstrated that ERβ can be recruited to the promoters of MCP-1 and CINC-2β during co-treatment with TNF-α and E2.These data demonstrate that E2 inhibits inflammation in RASMCs by two distinct mechanisms: promoting new synthesis of IκBα, thus accelerating a negative feedback loop in NFκB signaling, and directly inhibiting binding of NFκB to the promoters of inflammatory genes. This first demonstration of multifaceted modulation of NFκB signaling by E2 may represent a novel mechanism by which E2 protects the vasculature against inflammatory injury.

  14. Thromboxane A{sub 2} receptor signaling promotes liver tissue repair after toxic injury through the enhancement of macrophage recruitment

    Energy Technology Data Exchange (ETDEWEB)

    Minamino, Tsutomu [Departments of Pharmacology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Departments of Gastroenterology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Ito, Yoshiya [Departments of Surgery, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Ohkubo, Hirotoki [Departments of Pharmacology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Departments of Surgery, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Hosono, Kanako; Suzuki, Tatsunori [Departments of Pharmacology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Sato, Takehito [Departments of Pharmacology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Departments of Gastroenterology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Ae, Takako; Shibuya, Akitaka [Departments of Gastroenterology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Sakagami, Hiroyuki [Departments of Anatomy, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Narumiya, Shuh [Department of Pharmacology, Kyoto University School of Medicine, Kyoto, 606-8315 (Japan); Koizumi, Wasaburo [Departments of Gastroenterology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan); Majima, Masataka, E-mail: mmajima@med.kitasato-u.ac.jp [Departments of Pharmacology, Kitasato University School of Medicine, Kanagawa 252-0374 (Japan)

    2012-02-15

    It is thought that thromboxane A{sub 2} (TxA{sub 2}) contributes to the progression of inflammation during acute hepatic injury; however, it is still unknown whether TxA{sub 2} is involved in liver repair. The objective of the present study was to examine the role of TxA{sub 2} receptor (TP) signaling in liver injury and repair in response to toxic injury. Carbon tetrachloride (CCl{sub 4}) was used to induce liver injury in TP knockout (TP{sup −/−}) mice and wild-type (WT) mice. In WT mice, serum levels of alanine aminotransferase (ALT) and the size of the necrotic area peaked at 24 and 48 h, respectively, and then declined. In TP{sup −/−} mice, the changes in ALT levels were similar to WT mice, but liver regeneration was impaired as evidenced by remained elevated levels of hepatic necrosis and by delayed hepatocyte proliferation, which was associated with the reduced expression of growth factors including interleukin-6 (IL-6), tumor necrosis factor alpha (TNFα), and hepatocyte growth factor (HGF). In TP{sup −/−} mice, the accumulation of hepatic CD11b{sup +}/F4/80{sup +} macrophages in injured livers was attenuated, and the hepatic expression of monocyte chemoattractant protein-1 (MCP-1/CCL2) and its receptor, the C―C chemokine receptor (CCR2), was reduced compared to WT. Additionally, the application of the TP receptor agonist, U-46619, enhanced the expression of MCP-1/CCL2 and CCR2 in peritoneal macrophages, which was associated with increased levels of IL-6, TNFα and HGF. These results suggested that TP receptor signaling facilitates liver recovery following CCl{sub 4}-induced hepatotoxicity by affecting the expression of hepatotrophic growth factors, and through the recruitment of macrophages mediated by MCP-1/CCL2-CCR2 expression. -- Highlights: ► TP enhances liver regeneration by CCl{sub 4}. ► TP accumulates macrophages. ► TP up-regulates MCP-1.

  15. A conserved TATA-less proximal promoter drives basal transcription from the urokinase-type plasminogen activator receptor gene

    DEFF Research Database (Denmark)

    Soravia, E; Grebe, A; De Luca, P

    1995-01-01

    have cloned an uPAR DNA segment containing upstream regulatory sequences from both the human and murine genomes. We report that a proximal promoter, contained within 180 bp from the major transcription start sites of the human uPAR gene, drives basal transcription. This region lacks TATA and CAAT boxes...... and contains relatively GC-rich proximal sequences. A subregion of this sequence, highly conserved between human and murine genes, contains most of the promoter activity and is specifically bound by HeLa nuclear proteins, one of which belongs to the SP1 class....

  16. The Ewing sarcoma protein (EWS) binds directly to the proximal elements of the macrophage-specific promoter of the CSF-1 receptor (csf1r) gene.

    Science.gov (United States)

    Hume, David A; Sasmono, Tedjo; Himes, S Roy; Sharma, Sudarshana M; Bronisz, Agnieszka; Constantin, Myrna; Ostrowski, Michael C; Ross, Ian L

    2008-05-15

    Many macrophage-specific promoters lack classical transcriptional start site elements such as TATA boxes and Sp1 sites. One example is the CSF-1 receptor (CSF-1R, CD115, c-fms), which is used as a model of the transcriptional regulation of macrophage genes. To understand the molecular basis of start site recognition in this gene, we identified cellular proteins binding specifically to the transcriptional start site (TSS) region. The mouse and human csf1r TSS were identified using cap analysis gene expression (CAGE) data. Conserved elements flanking the TSS cluster were analyzed using EMSAs to identify discrete DNA-binding factors in primary bone marrow macrophages as candidate transcriptional regulators. Two complexes were identified that bind in a highly sequence-specific manner to the mouse and human TSS proximal region and also to high-affinity sites recognized by myeloid zinc finger protein 1 (Mzf1). The murine proteins were purified by DNA affinity isolation from the RAW264.7 macrophage cell line and identified by mass spectrometry as EWS and FUS/TLS, closely related DNA and RNA-binding proteins. Chromatin immunoprecipitation experiments in bone marrow macrophages confirmed that EWS, but not FUS/TLS, was present in vivo on the CSF-1R proximal promoter in unstimulated primary macrophages. Transfection assays suggest that EWS does not act as a conventional transcriptional activator or repressor. We hypothesize that EWS contributes to start site recognition in TATA-less mammalian promoters.

  17. Receptor Protein Tyrosine Phosphatase α-Mediated Enhancement of Rheumatoid Synovial Fibroblast Signaling and Promotion of Arthritis in Mice

    NARCIS (Netherlands)

    Stanford, Stephanie M; Svensson, Mattias N D; Sacchetti, Cristiano; Pilo, Caila A; Wu, Dennis J; Kiosses, William B; Hellvard, Annelie; Bergum, Brith; Muench, German R Aleman; Elly, Christian; Liu, Yun-Cai; den Hertog, Jeroen; Elson, Ari; Sap, Jan; Mydel, Piotr; Boyle, David L; Corr, Maripat; Firestein, Gary S; Bottini, Nunzio

    OBJECTIVE: During rheumatoid arthritis (RA), fibroblast-like synoviocytes (FLS) critically promote disease pathogenesis by aggressively invading the extracellular matrix of the joint. The focal adhesion kinase (FAK) signaling pathway is emerging as a contributor to the anomalous behavior of RA FLS.

  18. Peroxisome proliferator-activated receptor gamma recruits the positive transcription elongation factor b complex to activate transcription and promote adipogenesis

    DEFF Research Database (Denmark)

    Iankova, Irena; Petersen, Rasmus K; Annicotte, Jean-Sébastien

    2006-01-01

    Positive transcription elongation factor b (P-TEFb) phosphorylates the C-terminal domain of RNA polymerase II, facilitating transcriptional elongation. In addition to its participation in general transcription, P-TEFb is recruited to specific promoters by some transcription factors such as c-Myc...

  19. A conserved TATA-less proximal promoter drives basal transcription from the urokinase-type plasminogen activator receptor gene

    DEFF Research Database (Denmark)

    Soravia, E; Grebe, A; De Luca, P

    1995-01-01

    have cloned an uPAR DNA segment containing upstream regulatory sequences from both the human and murine genomes. We report that a proximal promoter, contained within 180 bp from the major transcription start sites of the human uPAR gene, drives basal transcription. This region lacks TATA and CAAT boxes...

  20. A novel synthetic analogue of ω-3 17,18-epoxyeicosatetraenoic acid activates TNF receptor-1/ASK1/JNK signaling to promote apoptosis in human breast cancer cells.

    Science.gov (United States)

    Dyari, Herryawan Ryadi Eziwar; Rawling, Tristan; Chen, Yongjuan; Sudarmana, William; Bourget, Kirsi; Dwyer, Julie M; Allison, Sarah E; Murray, Michael

    2017-12-01

    A saturated analog of the cytochrome P450-mediated ω-3-17,18-epoxide of ω-3-eicosapentaenoic acid (C20E) activated apoptosis in human triple-negative MDA-MB-231 breast cancer cells. This study evaluated the apoptotic mechanism of C20E. Increased cytosolic cytochrome c expression and altered expression of pro- and antiapoptotic B-cell lymphoma-2 proteins indicated activation of the mitochondrial pathway. Caspase-3 activation by C20E was prevented by pharmacological inhibition and silencing of the JNK and p38 MAP kinases (MAPK), upstream MAPK kinases MKK4 and MKK7, and the upstream MAPK kinase kinase apoptosis signal-regulating kinase 1 (ASK1). Silencing of the death receptor TNF receptor 1 (TNFR1), but not Fas, DR4, or DR5, and the adapters TRADD and TNF receptor-associated factor 2, but not Fas-associated death domain, prevented C20E-mediated apoptosis. B-cell lymphoma-2 homology 3-interacting domain death agonist (Bid) cleavage by JNK/p38 MAPK linked the extrinsic and mitochondrial pathways of apoptosis. In further studies, an antibody against the extracellular domain of TNFR1 prevented apoptosis by TNF-α but not C20E. These findings suggest that C20E acts intracellularly at TNFR1 to activate ASK1-MKK4/7-JNK/p38 MAPK signaling and to promote Bid-dependent mitochondrial disruption and apoptosis. In in vivo studies, tumors isolated from C20E-treated nu/nu mice carrying MDA-MB-231 xenografts showed increased TUNEL staining and decreased Ki67 staining, reflecting increased apoptosis and decreased proliferation, respectively. ω-3-Epoxy fatty acids like C20E could be incorporated into treatments for triple-negative breast cancers.-Dyari, H. R. E., Rawling, T., Chen, Y., Sudarmana, W., Bourget, K., Dwyer, J. M., Allison, S. E., Murray, M. A novel synthetic analogue of ω-3 17,18-epoxyeicosatetraenoic acid activates TNF receptor-1/ASK1/JNK signaling to promote apoptosis in human breast cancer cells. © FASEB.

  1. PDGF receptor-α does not promote HCMV entry into epithelial and endothelial cells but increased quantities stimulate entry by an abnormal pathway.

    Directory of Open Access Journals (Sweden)

    Adam L Vanarsdall

    2012-09-01

    Full Text Available Epidermal growth factor receptor (EGFR and platelet-derived growth factor receptor-α (PDGFRα were reported to mediate entry of HCMV, including HCMV lab strain AD169. AD169 cannot assemble gH/gL/UL128-131, a glycoprotein complex that is essential for HCMV entry into biologically important epithelial cells, endothelial cells, and monocyte-macrophages. Given this, it appeared incongruous that EGFR and PDGFRα play widespread roles in HCMV entry. Thus, we investigated whether PDGFRα and EGFR could promote entry of wild type HCMV strain TR. EGFR did not promote HCMV entry into any cell type. PDGFRα-transduction of epithelial and endothelial cells and several non-permissive cells markedly enhanced HCMV TR entry and surprisingly, promoted entry of HCMV mutants lacking gH/gL/UL128-131 into epithelial and endothelial cells. Entry of HCMV was not blocked by a panel of PDGFRα antibodies or the PDGFR ligand in fibroblasts, epithelial, or endothelial cells or by shRNA silencing of PDGFRα in epithelial cells. Moreover, HCMV glycoprotein induced cell-cell fusion was not increased when PDGFRα was expressed in cells. Together these results suggested that HCMV does not interact directly with PDGFRα. Instead, the enhanced entry produced by PDGFRα resulted from a novel entry pathway involving clathrin-independent, dynamin-dependent endocytosis of HCMV followed by low pH-independent fusion. When PDGFRα was expressed in cells, an HCMV lab strain escaped endosomes and tegument proteins reached the nucleus, but without PDGFRα virions were degraded. By contrast, wild type HCMV uses another pathway to enter epithelial cells involving macropinocytosis and low pH-dependent fusion, a pathway that lab strains (lacking gH/gL/UL128-131 cannot follow. Thus, PDGFRα does not act as a receptor for HCMV but increased PDGFRα alters cells, facilitating virus entry by an abnormal pathway. Given that PDGFRα increased infection of some cells to 90%, PDGFRα may be very

  2. Transient receptor potential ankyrin 1 channel localized to non-neuronal airway cells promotes non-neurogenic inflammation

    DEFF Research Database (Denmark)

    Nassini, Romina; Pedretti, Pamela; Moretto, Nadia

    2012-01-01

    and fibroblasts, acrolein and CS extract evoked IL-8 release, a response selectively reduced by TRPA1 antagonists. Capsaicin, agonist of the transient receptor potential vanilloid 1 (TRPV1), a channel co-expressed with TRPA1 by airway sensory nerves, and acrolein or CS (TRPA1 agonists), or the neuropeptide...... substance P (SP), which is released from sensory nerve terminals by capsaicin, acrolein or CS), produced neurogenic inflammation in mouse airways. However, only acrolein and CS, but not capsaicin or SP, released the keratinocyte chemoattractant (CXCL-1/KC, IL-8 analogue) in bronchoalveolar lavage (BAL...

  3. Constitutive Signaling from an Engineered IL7 Receptor Promotes Durable Tumor Elimination by Tumor-Redirected T Cells.

    Science.gov (United States)

    Shum, Thomas; Omer, Bilal; Tashiro, Haruko; Kruse, Robert L; Wagner, Dimitrios L; Parikh, Kathan; Yi, Zhongzhen; Sauer, Tim; Liu, Daofeng; Parihar, Robin; Castillo, Paul; Liu, Hao; Brenner, Malcolm K; Metelitsa, Leonid S; Gottschalk, Stephen; Rooney, Cliona M

    2017-11-01

    Successful adoptive T-cell immunotherapy of solid tumors will require improved expansion and cytotoxicity of tumor-directed T cells within tumors. Providing recombinant or transgenic cytokines may produce the desired benefits but is associated with significant toxicities, constraining clinical use. To circumvent this limitation, we constructed a constitutively signaling cytokine receptor, C7R, which potently triggers the IL7 signaling axis but is unresponsive to extracellular cytokine. This strategy augments modified T-cell function following antigen exposure, but avoids stimulating bystander lymphocytes. Coexpressing the C7R with a tumor-directed chimeric antigen receptor (CAR) increased T-cell proliferation, survival, and antitumor activity during repeated exposure to tumor cells, without T-cell dysfunction or autonomous T-cell growth. Furthermore, C7R-coexpressing CAR T cells were active against metastatic neuroblastoma and orthotopic glioblastoma xenograft models even at cell doses that had been ineffective without C7R support. C7R may thus be able to enhance antigen-specific T-cell therapies against cancer. Significance: The constitutively signaling C7R system developed here delivers potent IL7 stimulation to CAR T cells, increasing their persistence and antitumor activity against multiple preclinical tumor models, supporting its clinical development. Cancer Discov; 7(11); 1238-47. ©2017 AACR. This article is highlighted in the In This Issue feature, p. 1201 . ©2017 American Association for Cancer Research.

  4. Overexpression of Poplar Pyrabactin Resistance-Like Abscisic Acid Receptors Promotes Abscisic Acid Sensitivity and Drought Resistance in Transgenic Arabidopsis.

    Directory of Open Access Journals (Sweden)

    Jingling Yu

    Full Text Available Drought stress is an important environmental factor limiting productivity of plants, especially fast growing species with high water consumption like poplar. Abscisic acid (ABA is a phytohormone that positively regulates seed dormancy and drought resistance. The PYR1 (Pyrabactin Resistance 1/ PYRL (PYR-Like/ RCAR (Regulatory Component of ABA Receptor (PYR/PYL/RCAR ABA receptor family has been identified and widely characterized in Arabidopsis thaliana. However, their functions in poplars remain unknown. Here, we report that 2 of 14 PYR/PYL/RCAR orthologues in poplar (Populus trichocarpa (PtPYRLs function as a positive regulator of the ABA signal transduction pathway. The Arabidopsis transient expression and yeast two-hybrid assays showed the interaction among PtPYRL1 and PtPYRL5, a clade A protein phosphatase 2C, and a SnRK2, suggesting that a core signalling complex for ABA signaling pathway exists in poplars. Phenotypic analysis of PtPYRL1 and PtPYRL5 transgenic Arabidopsis showed that these two genes positively regulated the ABA responses during the seed germination. More importantly, the overexpression of PtPYRL1 and PtPYRL5 substantially improved ABA sensitivity and drought stress tolerance in transgenic plants. In summary, we comprehensively uncovered the properties of PtPYRL1 and PtPYRL5, which might be good target genes to genetically engineer drought-Resistant plants.

  5. Wake-promoting effects of vagus nerve stimulation after traumatic brain injury: upregulation of orexin-A and orexin receptor type 1 expression in the prefrontal cortex.

    Science.gov (United States)

    Dong, Xiao-Yang; Feng, Zhen

    2018-02-01

    Orexins, produced in the lateral hypothalamus, are important neuropeptides that participate in the sleep/wake cycle, and their expression coincides with the projection area of the vagus nerve in the brain. Vagus nerve stimulation has been shown to decrease the amounts of daytime sleep and rapid eye movement in epilepsy patients with traumatic brain injury. In the present study, we investigated whether vagus nerve stimulation promotes wakefulness and affects orexin expression. A rat model of traumatic brain injury was established using the free fall drop method. In the stimulated group, rats with traumatic brain injury received vagus nerve stimulation (frequency, 30 Hz; current, 1.0 mA; pulse width, 0.5 ms; total stimulation time, 15 minutes). In the antagonist group, rats with traumatic brain injury were intracerebroventricularly injected with the orexin receptor type 1 (OX1R) antagonist SB334867 and received vagus nerve stimulation. Changes in consciousness were observed after stimulation in each group. Enzyme-linked immunosorbent assay, western blot assay and immunohistochemistry were used to assess the levels of orexin-A and OX1R expression in the prefrontal cortex. In the stimulated group, consciousness was substantially improved, orexin-A protein expression gradually increased within 24 hours after injury and OX1R expression reached a peak at 12 hours, compared with rats subjected to traumatic brain injury only. In the antagonist group, the wake-promoting effect of vagus nerve stimulation was diminished, and orexin-A and OX1R expression were decreased, compared with that of the stimulated group. Taken together, our findings suggest that vagus nerve stimulation promotes the recovery of consciousness in comatose rats after traumatic brain injury. The upregulation of orexin-A and OX1R expression in the prefrontal cortex might be involved in the wake-promoting effects of vagus nerve stimulation.

  6. Diphenylarsinic acid, a chemical warfare-related neurotoxicant, promotes liver carcinogenesis via activation of aryl hydrocarbon receptor signaling and consequent induction of oxidative DAN damage in rats

    Energy Technology Data Exchange (ETDEWEB)

    Wei, Min; Yamada, Takanori; Yamano, Shotaro; Kato, Minoru; Kakehashi, Anna; Fujioka, Masaki; Tago, Yoshiyuki; Kitano, Mistuaki; Wanibuchi, Hideki, E-mail: wani@med.osaka-cu.ac.jp

    2013-11-15

    Diphenylarsinic acid (DPAA), a chemical warfare-related neurotoxic organic arsenical, is present in the groundwater and soil in some regions of Japan due to illegal dumping after World War II. Inorganic arsenic is carcinogenic in humans and its organic arsenic metabolites are carcinogenic in animal studies, raising serious concerns about the carcinogenicity of DPAA. However, the carcinogenic potential of DPAA has not yet been evaluated. In the present study we found that DPAA significantly enhanced the development of diethylnitrosamine-induced preneoplastic lesions in the liver in a medium-term rat liver carcinogenesis assay. Evaluation of the expression of cytochrome P450 (CYP) enzymes in the liver revealed that DPAA induced the expression of CYP1B1, but not any other CYP1, CYP2, or CYP3 enzymes, suggesting that CYP1B1 might be the enzyme responsible for the metabolic activation of DPAA. We also found increased oxidative DNA damage, possibly due to elevated CYP1B1 expression. Induction of CYP1B1 has generally been linked with the activation of AhR, and we found that DPAA activates the aryl hydrocarbon receptor (AhR). Importantly, the promotion effect of DPAA was observed only at a dose that activated the AhR, suggesting that activation of AhR and consequent induction of AhR target genes and oxidative DNA damage plays a vital role in the promotion effects of DPAA. The present study provides, for the first time, evidence regarding the carcinogenicity of DPAA and indicates the necessity of comprehensive evaluation of its carcinogenic potential using long-term carcinogenicity studies. - Highlights: • DPAA, an environmental neurotoxicant, promotes liver carcinogenesis in rats. • DPAA is an activator of AhR signaling pathway. • DPAA promoted oxidative DNA damage in rat livers. • AhR target gene CYP 1B1 might be involved in the metabolism of DPAA.

  7. Characterization of the human Activin-A receptor type II-like kinase 1 (ACVRL1 promoter and its regulation by Sp1

    Directory of Open Access Journals (Sweden)

    Botella Luisa M

    2010-06-01

    Full Text Available Abstract Background Activin receptor-like kinase 1 (ALK1 is a Transforming Growth Factor-β (TGF-β receptor type I, mainly expressed in endothelial cells that plays a pivotal role in vascular remodelling and angiogenesis. Mutations in the ALK1 gene (ACVRL1 give rise to Hereditary Haemorrhagic Telangiectasia, a dominant autosomal vascular dysplasia caused by a haploinsufficiency mechanism. In spite of its patho-physiological relevance, little is known about the transcriptional regulation of ACVRL1. Here, we have studied the different origins of ACVRL1 transcription, we have analyzed in silico its 5'-proximal promoter sequence and we have characterized the role of Sp1 in the transcriptional regulation of ACVRL1. Results We have performed a 5'Rapid Amplification of cDNA Ends (5'RACE of ACVRL1 transcripts, finding two new transcriptional origins, upstream of the one previously described, that give rise to a new exon undiscovered to date. The 5'-proximal promoter region of ACVRL1 (-1,035/+210 was analyzed in silico, finding that it lacks TATA/CAAT boxes, but contains a remarkably high number of GC-rich Sp1 consensus sites. In cells lacking Sp1, ACVRL1 promoter reporters did not present any significant transcriptional activity, whereas increasing concentrations of Sp1 triggered a dose-dependent stimulation of its transcription. Moreover, silencing Sp1 in HEK293T cells resulted in a marked decrease of ACVRL1 transcriptional activity. Chromatin immunoprecipitation assays demonstrated multiple Sp1 binding sites along the proximal promoter region of ACVRL1 in endothelial cells. Furthermore, demethylation of CpG islands, led to an increase in ACVRL1 transcription, whereas in vitro hypermethylation resulted in the abolishment of Sp1-dependent transcriptional activation of ACVRL1. Conclusions Our results describe two new transcriptional start sites in ACVRL1 gene, and indicate that Sp1 is a key regulator of ACVRL1 transcription, providing new insights into

  8. BAFF upregulates CD28/B7 and CD40/CD154 expression and promotes mouse T and B cell interaction in vitro via BAFF receptor.

    Science.gov (United States)

    Zhang, Feng; Song, Shan-Shan; Shu, Jin-Ling; Li, Ying; Wu, Yu-Jing; Wang, Qing-Tong; Chen, Jing-Yu; Chang, Yan; Wu, Hua-Xun; Zhang, Ling-Ling; Wei, Wei

    2016-08-01

    B cell-activating factor belonging to the TNF family (BAFF) is a member of TNF family and required for peripheral B cell survival and homeostasis. BAFF has been shown to promote the proliferation of T and B cells. In this study we examined whether and how BAFF mediated the interaction between mouse T and B cells in vitro. BAFF-stimulated B or T cells were co-cultured with T or B cells. The interactions between T and B cells were analyzed by measuring the expression of co-stimulatory molecules (CD28/CD80 or CD40/CD154), the proliferation and secretion of T and B cells and other factors. Two siRNAs against the transmembrane activator and calcium modulator and cyclophilin ligand interactor (TACI) and BAFF receptor (BAFF-R) were used to identify the receptors responsible for the actions of BAFF. BAFF-stimulated B cells significantly promoted the proliferation and activity of co-cultured T cells, and increased the percentages of CD4(+)CD28(+) and CD4(+)CD154(+) T cells. Similarly, BAFF-stimulated T cells significantly promoted the proliferation and activity of co-cultured B cells, and increased CD19(+)CD80(+) and CD19(+)CD40(+)B cell subpopulations. BAFF-R siRNA-silenced B cells showed significantly lower expression of CD40 and CD80 than the control B cells. When the BAFF-R siRNA-silenced B cells were stimulated with BAFF, then co-cultured with T cells, the expression of CD28 and CD154 on T cells was not increased. TACI siRNA-silenced B cells exhibited higher expression of CD40 and CD80 than the control B cells. When the TACI siRNA-silenced B cells were stimulated with BAFF, then co-cultured with T cells, the expression of CD28 and CD154 on T cells was significantly increased. BAFF upregulates CD28/B7 and CD40/CD154 expression, and promotes the interactions between T and B cells in a BAFF-R-dependent manner.

  9. OXER1, a G protein-coupled oxoeicosatetraenoid receptor, mediates the survival-promoting effects of arachidonate 5-lipoxygenase in prostate cancer cells

    Science.gov (United States)

    Sarveswaran, Sivalokanathan; Ghosh, Jagadananda

    2013-01-01

    Inhibition of 5-Lox induces apoptosis in prostate cancer cells by inactivating PKCε which is prevented by 5-oxoETE, and activators of PKCε prevent 5-Lox inhibition-induced apoptosis, suggesting that 5-Lox metabolites exert survival signaling via PKCε. However, mechanisms by which 5-Lox metabolites activate PKCε are not understood yet. We found that prostate cancer cells express high levels of OXER1, a G protein-coupled 5-oxoETE receptor, which delivers signal by generating diacyl-glycerol through phospholipase C-beta. Interestingly, we found that U73122, an inhibitor of PLC-beta, interrupts the apoptosis-preventing effect of 5-oxoETE, and exogenous diacyl-glycerol effectively prevents 5-Lox inhibition-induced apoptosis, suggesting that 5-oxoETE signals via OXER1 to promote prostate cancer cell survival. PMID:23643940

  10. Histamine acting on H1 receptor promotes inhibition of proliferation via PLC, RAC, and JNK-dependent pathways

    Energy Technology Data Exchange (ETDEWEB)

    Notcovich, Cintia [Laboratorio de Patologia y Farmacologia Molecular, Instituto de Biologia y Medicina Experimental (Argentina); Laboratorio de Farmacologia de Receptores, Catedra de Quimica Medicinal, Departamento de Farmacologia, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Diez, Federico [Laboratorio de Farmacologia de Receptores, Catedra de Quimica Medicinal, Departamento de Farmacologia, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Tubio, Maria Rosario [Laboratorio de Patologia y Farmacologia Molecular, Instituto de Biologia y Medicina Experimental (Argentina); Laboratorio de Farmacologia de Receptores, Catedra de Quimica Medicinal, Departamento de Farmacologia, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Baldi, Alberto [Laboratorio de Patologia y Farmacologia Molecular, Instituto de Biologia y Medicina Experimental (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Kazanietz, Marcelo G. [Department of Pharmacology, University of Pennsylvania School of Medicine, Philadelphia, PA 19104 (United States); Davio, Carlos [Laboratorio de Farmacologia de Receptores, Catedra de Quimica Medicinal, Departamento de Farmacologia, Facultad de Farmacia y Bioquimica, Universidad de Buenos Aires (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina); Shayo, Carina, E-mail: cshayo@dna.uba.ar [Laboratorio de Patologia y Farmacologia Molecular, Instituto de Biologia y Medicina Experimental (Argentina); Consejo Nacional de Investigaciones Cientificas y Tecnicas, Buenos Aires (Argentina)

    2010-02-01

    It is well established that histamine modulates cell proliferation through the activation of the histamine H1 receptor (H1R), a G protein-coupled receptor (GPCR) that is known to couple to phospholipase C (PLC) activation via Gq. In the present study, we aimed to determine whether H1R activation modulates Rho GTPases, well-known effectors of Gq/G{sub 11}-coupled receptors, and whether such modulation influences cell proliferation. Experiments were carried out in CHO cells stably expressing H1R (CHO-H1R). By using pull-down assays, we found that both histamine and a selective H1R agonist activated Rac and RhoA in a time- and dose-dependent manner without significant changes in the activation of Cdc42. Histamine response was abolished by the H1R antagonist mepyramine, RGS2 and the PLC inhibitor U73122, suggesting that Rac and RhoA activation is mediated by H1R via Gq coupling to PLC stimulation. Histamine caused a marked activation of serum response factor activity via the H1R, as determined with a serum-responsive element (SRE) luciferase reporter, and this response was inhibited by RhoA inactivation with C3 toxin. Histamine also caused a significant activation of JNK which was inhibited by expression of the Rac-GAP {beta}2-chimaerin. On the other hand, H1R-induced ERK1/2 activation was inhibited by U73122 but not affected by C3 or {beta}2-chimaerin, suggesting that ERK1/2 activation was dependent on PLC and independent of RhoA or Rac. [{sup 3}H]-Thymidine incorporation assays showed that both histamine and the H1R agonist inhibited cell proliferation in a dose-dependent manner and that the effect was independent of RhoA but partially dependent on JNK and Rac. Our results reveal that functional coupling of the H1R to Gq-PLC leads to the activation of RhoA and Rac small GTPases and suggest distinct roles for Rho GTPases in the control of cell proliferation by histamine.

  11. Histamine acting on H1 receptor promotes inhibition of proliferation via PLC, RAC, and JNK-dependent pathways

    International Nuclear Information System (INIS)

    Notcovich, Cintia; Diez, Federico; Tubio, Maria Rosario; Baldi, Alberto; Kazanietz, Marcelo G.; Davio, Carlos; Shayo, Carina

    2010-01-01

    It is well established that histamine modulates cell proliferation through the activation of the histamine H1 receptor (H1R), a G protein-coupled receptor (GPCR) that is known to couple to phospholipase C (PLC) activation via Gq. In the present study, we aimed to determine whether H1R activation modulates Rho GTPases, well-known effectors of Gq/G 11 -coupled receptors, and whether such modulation influences cell proliferation. Experiments were carried out in CHO cells stably expressing H1R (CHO-H1R). By using pull-down assays, we found that both histamine and a selective H1R agonist activated Rac and RhoA in a time- and dose-dependent manner without significant changes in the activation of Cdc42. Histamine response was abolished by the H1R antagonist mepyramine, RGS2 and the PLC inhibitor U73122, suggesting that Rac and RhoA activation is mediated by H1R via Gq coupling to PLC stimulation. Histamine caused a marked activation of serum response factor activity via the H1R, as determined with a serum-responsive element (SRE) luciferase reporter, and this response was inhibited by RhoA inactivation with C3 toxin. Histamine also caused a significant activation of JNK which was inhibited by expression of the Rac-GAP β2-chimaerin. On the other hand, H1R-induced ERK1/2 activation was inhibited by U73122 but not affected by C3 or β2-chimaerin, suggesting that ERK1/2 activation was dependent on PLC and independent of RhoA or Rac. [ 3 H]-Thymidine incorporation assays showed that both histamine and the H1R agonist inhibited cell proliferation in a dose-dependent manner and that the effect was independent of RhoA but partially dependent on JNK and Rac. Our results reveal that functional coupling of the H1R to Gq-PLC leads to the activation of RhoA and Rac small GTPases and suggest distinct roles for Rho GTPases in the control of cell proliferation by histamine.

  12. Aberrant intestinal microbiota due to IL-1 receptor antagonist deficiency promotes IL-17- and TLR4-dependent arthritis.

    Science.gov (United States)

    Rogier, Rebecca; Ederveen, Thomas H A; Boekhorst, Jos; Wopereis, Harm; Scher, Jose U; Manasson, Julia; Frambach, Sanne J C M; Knol, Jan; Garssen, Johan; van der Kraan, Peter M; Koenders, Marije I; van den Berg, Wim B; van Hijum, Sacha A F T; Abdollahi-Roodsaz, Shahla

    2017-06-23

    Perturbation of commensal intestinal microbiota has been associated with several autoimmune diseases. Mice deficient in interleukin-1 receptor antagonist (Il1rn -/- mice) spontaneously develop autoimmune arthritis and are susceptible to other autoimmune diseases such as psoriasis, diabetes, and encephalomyelitis; however, the mechanisms of increased susceptibility to these autoimmune phenotypes are poorly understood. We investigated the role of interleukin-1 receptor antagonist (IL-1Ra) in regulation of commensal intestinal microbiota, and assessed the involvement of microbiota subsets and innate and adaptive mucosal immune responses that underlie the development of spontaneous arthritis in Il1rn -/- mice. Using high-throughput 16S rRNA gene sequencing, we show that IL-1Ra critically maintains the diversity and regulates the composition of intestinal microbiota in mice. IL-1Ra deficiency reduced the intestinal microbial diversity and richness, and caused specific taxonomic alterations characterized by overrepresented Helicobacter and underrepresented Ruminococcus and Prevotella. Notably, the aberrant intestinal microbiota in IL1rn -/- mice specifically potentiated IL-17 production by intestinal lamina propria (LP) lymphocytes and skewed the LP T cell balance in favor of T helper 17 (Th17) cells, an effect transferable to WT mice by fecal microbiota. Importantly, LP Th17 cell expansion and the development of spontaneous autoimmune arthritis in IL1rn -/- mice were attenuated under germ-free condition. Selective antibiotic treatment revealed that tobramycin-induced alterations of commensal intestinal microbiota, i.e., reduced Helicobacter, Flexispira, Clostridium, and Dehalobacterium, suppressed arthritis in IL1rn -/- mice. The arthritis phenotype in IL1rn -/- mice was previously shown to depend on Toll-like receptor 4 (TLR4). Using the ablation of both IL-1Ra and TLR4, we here show that the aberrations in the IL1rn -/- microbiota are partly TLR4-dependent. We further

  13. Hepatitis C virus E2 protein promotes human hepatoma cell proliferation through the MAPK/ERK signaling pathway via cellular receptors

    International Nuclear Information System (INIS)

    Zhao Lanjuan; Wang Lu; Ren Hao; Cao Jie; Li Li; Ke Jinshan; Qi Zhongtian

    2005-01-01

    Dysregulation of mitogen-activated protein kinase (MAPK) signaling pathways by various viruses has been shown to be responsible for viral pathogenicity. The molecular mechanism by which hepatitis C virus (HCV) infection caused human liver diseases has been investigated on the basis of abnormal intracellular signal events. Current data are very limited involved in transmembrane signal transduction triggered by HCV E2 protein. Here we explored regulation of the MAPK/extracellular signal-regulated kinase (MAPK/ERK) signaling pathway by E2 expressed in Chinese hamster oval cells. In human hepatoma Huh-7 cells, E2 specifically activated the MAPK/ERK pathway including downstream transcription factor ATF-2 and greatly promoted cell proliferation. CD81 and low density lipoprotein receptor (LDLR) on the cell surface mediated binding of E2 to Huh-7 cells. The MAPK/ERK activation and cell proliferation driven by E2 were suppressed by blockage of CD81 as well as LDLR. Furthermore, pretreatment with an upstream kinase MEK1/2 inhibitor U0126 also impaired the MAPK/ERK activation and cell proliferation induced by E2. Our results suggest that the MAPK/ERK signaling pathway triggered by HCV E2 via its receptors maintains survival and growth of target cells

  14. Essential role for retinoic acid in the promotion of CD4+ T cell effector responses via retinoic acid receptor alpha

    Science.gov (United States)

    Hall, J.A.; Cannons, J.L.; Grainger, J.R.; Santos, L.M. Dos; Hand, T.W.; Naik, S.; Wohlfert, E.A.; Chou, D.B.; Oldenhove, G.; Robinson, M.; Grigg, M.E.; Kastenmayer, R.; Schwartzberg, P.L.; Belkaid, Y.

    2012-01-01

    SUMMARY Vitamin A and its metabolite, retinoic acid (RA), have recently been implicated in the regulation of immune homeostasis via the peripheral induction of regulatory T cells. Here we show that RA is also required to elicit proinflammatory CD4+ helper T cell responses to infection and mucosal vaccination. Retinoic acid receptor alpha (RARα) is the critical mediator of these effects. Strikingly, antagonism of RAR signaling and deficiency in RARα(Rara−/−) results in a cell autonomous CD4+ T cell activation defect. Altogether, these findings reveal a fundamental role for the RA/RARα axis in the development of both regulatory and inflammatory arms of adaptive immunity and establish nutritional status as a broad regulator of adaptive T cell responses. PMID:21419664

  15. Muscarinic M1 receptor inhibition reduces gastroduodenal bicarbonate secretion and promotes gastric prostaglandin E2 synthesis in healthy volunteers

    DEFF Research Database (Denmark)

    Mertz-Nielsen, A; Hillingsø, Jens; Eskerod, O

    1995-01-01

    The selective muscarinic M1 receptor antagonist, pirenzepine, considerably stimulates duodenal mucosal bicarbonate secretion in the rat and increases gastric luminal release of prostaglandin E2 (PGE2) in humans. This study, therefore, looked at the effect of pirenzepine on bicarbonate secretion...... and luminal output of PGE2 into the stomach and the duodenum of nine healthy volunteers using a new technique permitting simultaneous measurements. In the stomach modified sham feeding increased bicarbonate secretion from 382 (62) mumol/h (mean (SEM)) to 959 (224) mumol/h (p ... sham feeding and acid exposure (HCl 0.1 M; 20 ml; 5 min) of the duodenal bulb increased mucosal bicarbonate secretion from 191 (14) mumol/cm x h to 266 (27) mumol/cm x h (p

  16. Vascular Endothelial Growth Factor Receptor 2 (VEGFR-2) Functions to Promote Uterine Decidual Angiogenesis during Early Pregnancy in the Mouse

    Science.gov (United States)

    Douglas, Nataki C.; Tang, Hongyan; Gomez, Raul; Pytowski, Bronislaw; Hicklin, Daniel J.; Sauer, Christopher M.; Kitajewski, Jan; Sauer, Mark V.; Zimmermann, Ralf C.

    2009-01-01

    Implantation of an embryo induces rapid proliferation and differentiation of uterine stromal cells, forming a new structure, the decidua. One salient feature of decidua formation is a marked increase in maternal angiogenesis. Vascular endothelial growth factor (VEGF)-dependent pathways are active in the ovary, uterus, and embryo, and inactivation of VEGF function in any of these structures might prevent normal pregnancy development. We hypothesized that decidual angiogenesis is regulated by VEGF acting through specific VEGF receptors (VEGFRs). To test this hypothesis, we developed a murine pregnancy model in which systemic administration of a receptor-blocking antibody would act specifically on uterine angiogenesis and not on ovarian or embryonic angiogenesis. In our model, ovarian function was replaced with exogenous progesterone, and blocking antibodies were administered prior to embryonic expression of VEGFRs. After administration of a single dose of the anti-VEGFR-2 antibody during the peri-implantation period, no embryos were detected on embryonic d 10.5. The pregnancy was disrupted because of a significant reduction in decidual angiogenesis, which under physiological conditions peaks on embryonic d 5.5 and 6.5. Inactivation of VEGFR-3 reduced angiogenesis in the primary decidual zone, whereas administration of VEGFR-1 blocking antibodies had no effect. Pregnancy was not disrupted after administration of anti-VEGFR-3 or anti-VEGFR-1 antibodies. Thus, the VEGF/VEGFR-2 pathway plays a key role in the maintenance of early pregnancy through its regulation of peri-implantation angiogenesis in the uterine decidua. This newly formed decidual vasculature serves as the first exchange apparatus for the developing embryo until the placenta becomes functionally active. PMID:19406950

  17. Initial evidence that GLP-1 receptor blockade fails to suppress postprandial satiety or promote food intake in humans.

    Science.gov (United States)

    Melhorn, Susan J; Tyagi, Vidhi; Smeraglio, Anne; Roth, Christian L; Schur, Ellen A

    2014-11-01

    Glucagon-like peptide 1 (GLP-1) has incretin effects that are well-documented, but the independent role of GLP-1 action in human satiety perception is debated. We hypothesized that blockade of GLP-1 receptors would suppress postprandial satiety and increase voluntary food intake. After an overnight fast, eight normal weight participants (seven men, BMI 19-24.7 kg/m(2), age 19-29 year) were enrolled in a double-blind, placebo-controlled, randomized crossover study of the GLP-1 antagonist Exendin-[9-39] (Ex-9) to determine if the satiating effects of a meal are dependent on GLP-1 signaling in humans. Following a fasting blood draw, iv infusion of Ex-9 (600-750 pmol/kg/min) or saline began. Thirty minutes later, subjects consumed a standardized breakfast followed 90 min later (at the predicted time of maximal endogenous circulating GLP-1) by an ad libitum buffet meal to objectively measure satiety. Infusions ended once the buffet meal was complete. Visual analog scale ratings of hunger and fullness and serial assessments of plasma glucose, insulin, and GLP-1 concentrations were done throughout the experiment. Contrary to the hypothesis, during Ex-9 infusion subjects reported a greater decrease in hunger due to consumption of the breakfast (Ex-9 -62 ± 5; placebo -41 ± 9; P=0.01) than during placebo. There were no differences in ad libitum caloric intake between Ex-9 and placebo. Ex-9 increased glucose, insulin, and endogenous GLP-1, which may have counteracted any effects of Ex-9 infusion to block satiety signaling. Blockade of GLP-1 receptors failed to suppress subjective satiety following a standardized meal or increase voluntary food intake in healthy, normal-weight subjects. Copyright © 2014 Elsevier Ltd. All rights reserved.

  18. Biochanin A Promotes Proliferation that Involves a Feedback Loop of MicroRNA-375 and Estrogen Receptor Alpha in Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Jian Chen

    2015-01-01

    Full Text Available Background: Biochanin A and formononetin are O-methylated isoflavones that are isolated from the root of Astragalus membranaceus, and have antitumorigenic effects. Our previous studies found that formononetin triggered growth-inhibitory and apoptotic activities in MCF-7 breast cancer cells. We performed in vivo and in vitro studies to further investigate the potential effect of biochanin A in promoting cell proliferation in estrogen receptor (ER-positive cells, and to elucidate underlying mechanisms. Methods: ERα-positive breast cancer cells (T47D, MCF-7 were treated with biochanin A. The MTT assay and flow cytometry were used to assess cell proliferation and apoptosis. mRNA levels of ERα, Bcl-2, and miR-375 were quantified using real-time polymerase chain reaction. Compared with the control, low biochanin A concentrations (2-6 μM stimulated ERα-positive cell proliferation (T47D, MCF-7. The more sensitive T47D cells were used to study the relevant signaling pathway. Results: After treatment with biochanin A, ERα, miR-375, and Bcl-2 expression was significantly upregulated. Additionally, in the in vivo studies, uterine weight in ovariectomized mice treated with biochanin A increased significantly. Conclusion: This study demonstrated that biochanin A promoted ERα-positive cell proliferation through miR-375 activation and this mechanism is possibly involving in a miR-375 and ERα feedback loop.

  19. Activation of human basophils by combined toll-like receptor- and FcεRI-triggering can promote Th2 skewing of naive T helper cells.

    Science.gov (United States)

    Suurmond, Jolien; Stoop, Jeroen N; Rivellese, Felice; Bakker, Aleida M; Huizinga, Tom W J; Toes, René E M

    2014-02-01

    Basophils are mostly known for their involvement in allergic reactions. Recent studies in mice indicate a role for basophils in the induction of adaptive immunity, especially T helper 2 (Th2) responses. Therefore, it would be highly important to understand how basophils respond to pathogen-associated molecules, such as ligands for toll-like receptors (TLRs), and if the basophils could promote Th2 responses via these stimuli. To this end, the activation of basophils via TLRs in combination with activation via IgE was studied, as well as its effect on T helper cell skewing. Using quantitative PCR, we demonstrated the presence of mRNA for TLRs 1-8 in human basophils. Basophils responded to TLR triggering with differential cytokine production, but not with degranulation. Simultaneous triggering of TLRs and IgE led to synergy in production of IL-4, IL-8, IL-13, and RANTES. Furthermore, the synergistic effects on basophils mediated by IgE and TLR-4 triggering allowed robust Th2 skewing upon activation of naïve human CD4⁺ T cells. Our data show that human basophils respond to TLR ligands in synergy with IgE-mediated activation and that the cytokines produced can promote Th2 differentiation. These results indicate a role for basophils in the regulation of T-cell responses in humans. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. A pair of dopamine neurons target the D1-like dopamine receptor DopR in the central complex to promote ethanol-stimulated locomotion in Drosophila.

    Directory of Open Access Journals (Sweden)

    Eric C Kong

    2010-04-01

    Full Text Available Dopamine is a mediator of the stimulant properties of drugs of abuse, including ethanol, in mammals and in the fruit fly Drosophila. The neural substrates for the stimulant actions of ethanol in flies are not known. We show that a subset of dopamine neurons and their targets, through the action of the D1-like dopamine receptor DopR, promote locomotor activation in response to acute ethanol exposure. A bilateral pair of dopaminergic neurons in the fly brain mediates the enhanced locomotor activity induced by ethanol exposure, and promotes locomotion when directly activated. These neurons project to the central complex ellipsoid body, a structure implicated in regulating motor behaviors. Ellipsoid body neurons are required for ethanol-induced locomotor activity and they express DopR. Elimination of DopR blunts the locomotor activating effects of ethanol, and this behavior can be restored by selective expression of DopR in the ellipsoid body. These data tie the activity of defined dopamine neurons to D1-like DopR-expressing neurons to form a neural circuit that governs acute responding to ethanol.

  1. Impaired coactivator activity of the Gly482 variant of peroxisome proliferator-activated receptor γ coactivator-1α (PGC-1α) on mitochondrial transcription factor A (Tfam) promoter

    International Nuclear Information System (INIS)

    Choi, Yon-Sik; Hong, Jung-Man; Lim, Sunny; Ko, Kyung Soo; Pak, Youngmi Kim

    2006-01-01

    Mitochondrial dysfunction may cause diabetes or insulin resistance. Peroxisome proliferation-activated receptor-γ (PPAR-γ) coactivator-1 α (PGC-1α) increases mitochondrial transcription factor A (Tfam) resulting in mitochondrial DNA content increase. An association between a single nucleotide polymorphism (SNP), G1444A(Gly482Ser), of PGC-1α coding region and insulin resistance has been reported in some ethnic groups. In this study, we investigated whether a change of glycine to serine at codon 482 of PGC-1α affected the Tfam promoter activity. The cDNA of PGC-1α variant bearing either glycine or serine at 482 codon was transfected into Chang human hepatocyte cells. The PGC-1α protein bearing glycine had impaired coactivator activity on Tfam promoter-mediated luciferase. We analyzed the PGC-1α genotype G1444A and mitochondrial DNA (mtDNA) copy number from 229 Korean leukocyte genomic DNAs. Subjects with Gly/Gly had a 20% lower amount of peripheral blood mtDNA than did subjects with Gly/Ser and Ser/Ser (p < 0.05). No correlation was observed between diabetic parameters and PGC-1α genotypes in Koreans. These results suggest that PGC-1α variants with Gly/Gly at 482nd amino acid may impair the Tfam transcription, a regulatory function of mitochondrial biogenesis, resulting in dysfunctional mtDNA replication

  2. High mobility group box protein-1 promotes cerebral edema after traumatic brain injury via activation of toll-like receptor 4.

    Science.gov (United States)

    Laird, Melissa D; Shields, Jessica S; Sukumari-Ramesh, Sangeetha; Kimbler, Donald E; Fessler, R David; Shakir, Basheer; Youssef, Patrick; Yanasak, Nathan; Vender, John R; Dhandapani, Krishnan M

    2014-01-01

    Traumatic brain injury (TBI) is a major cause of mortality and morbidity worldwide. Cerebral edema, a life-threatening medical complication, contributes to elevated intracranial pressure (ICP) and a poor clinical prognosis after TBI. Unfortunately, treatment options to reduce post-traumatic edema remain suboptimal, due in part, to a dearth of viable therapeutic targets. Herein, we tested the hypothesis that cerebral innate immune responses contribute to edema development after TBI. Our results demonstrate that high-mobility group box protein 1 (HMGB1) was released from necrotic neurons via a NR2B-mediated mechanism. HMGB1 was clinically associated with elevated ICP in patients and functionally promoted cerebral edema after TBI in mice. The detrimental effects of HMGB1 were mediated, at least in part, via activation of microglial toll-like receptor 4 (TLR4) and the subsequent expression of the astrocytic water channel, aquaporin-4 (AQP4). Genetic or pharmacological (VGX-1027) TLR4 inhibition attenuated the neuroinflammatory response and limited post-traumatic edema with a delayed, clinically implementable therapeutic window. Human and rodent tissue culture studies further defined the cellular mechanisms demonstrating neuronal HMGB1 initiates the microglial release of interleukin-6 (IL-6) in a TLR4 dependent mechanism. In turn, microglial IL-6 increased the astrocytic expression of AQP4. Taken together, these data implicate microglia as key mediators of post-traumatic brain edema and suggest HMGB1-TLR4 signaling promotes neurovascular dysfunction after TBI. Copyright © 2013 Wiley Periodicals, Inc.

  3. Adenosine A1 receptors promote vasa vasorum endothelial cell barrier integrity via Gi and Akt-dependent actin cytoskeleton remodeling.

    Directory of Open Access Journals (Sweden)

    Siddaramappa Nagavedi Umapathy

    Full Text Available In a neonatal model of hypoxic pulmonary hypertension, a dramatic pulmonary artery adventitial thickening, accumulation of inflammatory cells in the adventitial compartment, and angiogenic expansion of the vasa vasorum microcirculatory network are observed. These pathophysiological responses suggest that rapidly proliferating vasa vasorum endothelial cells (VVEC may exhibit increased permeability for circulating blood cells and macromolecules. However, the molecular mechanisms underlying these observations remain unexplored. Some reports implicated extracellular adenosine in the regulation of vascular permeability under hypoxic and inflammatory conditions. Thus, we aimed to determine the role of adenosine in barrier regulation of VVEC isolated from the pulmonary arteries of normoxic (VVEC-Co or chronically hypoxic (VVEC-Hyp neonatal calves.We demonstrate via a transendothelial electrical resistance measurement that exogenous adenosine significantly enhanced the barrier function in VVEC-Co and, to a lesser extent, in VVEC-Hyp. Our data from a quantitative reverse transcription polymerase chain reaction show that both VVEC-Co and VVEC-Hyp express all four adenosine receptors (A1, A2A, A2B, and A3, with the highest expression level of A1 receptors (A1Rs. However, A1R expression was significantly lower in VVEC-Hyp compared to VVEC-Co. By using an A1R-specific agonist/antagonist and siRNA, we demonstrate that A1Rs are mostly responsible for adenosine-induced enhancement in barrier function. Adenosine-induced barrier integrity enhancement was attenuated by pretreatment of VVEC with pertussis toxin and GSK690693 or LY294002, suggesting the involvement of Gi proteins and the PI3K-Akt pathway. Moreover, we reveal a critical role of actin cytoskeleton in VVEC barrier regulation by using specific inhibitors of actin and microtubule polymerization. Further, we show that adenosine pretreatment blocked the tumor necrosis factor alpha (TNF

  4. Adenosine A1 Receptors Promote Vasa Vasorum Endothelial Cell Barrier Integrity via Gi and Akt-Dependent Actin Cytoskeleton Remodeling

    Science.gov (United States)

    Siddaramappa Umapathy, Nagavedi; Kaczmarek, Elzbieta; Fatteh, Nooreen; Burns, Nana; Lucas, Rudolf; Stenmark, Kurt R.; Verin, Alexander D.; Gerasimovskaya, Evgenia V.

    2013-01-01

    Background In a neonatal model of hypoxic pulmonary hypertension, a dramatic pulmonary artery adventitial thickening, accumulation of inflammatory cells in the adventitial compartment, and angiogenic expansion of the vasa vasorum microcirculatory network are observed. These pathophysiological responses suggest that rapidly proliferating vasa vasorum endothelial cells (VVEC) may exhibit increased permeability for circulating blood cells and macromolecules. However, the molecular mechanisms underlying these observations remain unexplored. Some reports implicated extracellular adenosine in the regulation of vascular permeability under hypoxic and inflammatory conditions. Thus, we aimed to determine the role of adenosine in barrier regulation of VVEC isolated from the pulmonary arteries of normoxic (VVEC-Co) or chronically hypoxic (VVEC-Hyp) neonatal calves. Principal Findings We demonstrate via a transendothelial electrical resistance measurement that exogenous adenosine significantly enhanced the barrier function in VVEC-Co and, to a lesser extent, in VVEC-Hyp. Our data from a quantitative reverse transcription polymerase chain reaction show that both VVEC-Co and VVEC-Hyp express all four adenosine receptors (A1, A2A, A2B, and A3), with the highest expression level of A1 receptors (A1Rs). However, A1R expression was significantly lower in VVEC-Hyp compared to VVEC-Co. By using an A1R-specific agonist/antagonist and siRNA, we demonstrate that A1Rs are mostly responsible for adenosine-induced enhancement in barrier function. Adenosine-induced barrier integrity enhancement was attenuated by pretreatment of VVEC with pertussis toxin and GSK690693 or LY294002, suggesting the involvement of Gi proteins and the PI3K-Akt pathway. Moreover, we reveal a critical role of actin cytoskeleton in VVEC barrier regulation by using specific inhibitors of actin and microtubule polymerization. Further, we show that adenosine pretreatment blocked the tumor necrosis factor alpha (TNF

  5. HBx induced AFP receptor expressed to activate PI3K/AKT signal to promote expression of Src in liver cells and hepatoma cells

    International Nuclear Information System (INIS)

    Zhu, Mingyue; Guo, Junli; Li, Wei; Xia, Hua; Lu, Yan; Dong, Xu; Chen, Yi; Xie, Xieju; Fu, Shigan; Li, Mengsen

    2015-01-01

    Hepatitis B virus (HBV)-X protein(HBx) is a transactivator of host several cellular genes including alpha-fetoprotein(AFP) and AFP receptor(AFPR) which contributes to HBV-associated tumor development. The expression of AFP/AFPR are correlated with hepatocellular carcinoma(HCC)-initial cells. But the role of AFP and AFPR in promoting occurrence of HBV-related HCC were still unclear. A total of 71 clinical patients’ liver specimens, normal human liver cells L-02 and HCC cell lines, PLC/PRF/5 were selected for analyzing the effects of HBx on expression of AFP, AFPR and Src. The expression of goal proteins were detected by Immunohistochemical stained and Western blotting; HBx-expressed vectors were constructed and transfected into L-02 cells, laser confocal microscopy was applied to observe expression and location of AFP, AFPR and Src in the normal liver cells and HCC cells, soft agar colony formation assay was used to observe colonies formed of the cells. We confirmed HBx gives preference to promote the expression of AFP and AFPR; HBx priors to up-regulate the expression of AFPR and AFP in L-02 cells and in normal liver specimens; AFPR signal been able to stimulate Src expression. The results also indicated that phosphatidylinositol 3-kinase(PI3K) inhibitors Ly294002 and GDC0941 effectively suppress AFPR mediated up-regulation expression of Src in AFPR positive HCC lines. HBx priors to drive the expression of AFP and AFPR to promote expression of Src in normal liver cells and hepatoma cells; AFP and AFPR maybe play pivotal role in HBV-related hepatocarcinogenesis; Targeting AFPR is an available therapeutic strategy of HCC. The online version of this article (doi:10.1186/s12885-015-1384-9) contains supplementary material, which is available to authorized users

  6. Tif1γ regulates the TGF-β1 receptor and promotes physiological aging of hematopoietic stem cells.

    Science.gov (United States)

    Quéré, Ronan; Saint-Paul, Laetitia; Carmignac, Virginie; Martin, Romain Z; Chrétien, Marie-Lorraine; Largeot, Anne; Hammann, Arlette; Pais de Barros, Jean-Paul; Bastie, Jean-Noël; Delva, Laurent

    2014-07-22

    The hematopoietic system declines with age. Myeloid-biased differentiation and increased incidence of myeloid malignancies feature aging of hematopoietic stem cells (HSCs), but the mechanisms involved remain uncertain. Here, we report that 4-mo-old mice deleted for transcription intermediary factor 1γ (Tif1γ) in HSCs developed an accelerated aging phenotype. To reinforce this result, we also show that Tif1γ is down-regulated in HSCs during aging in 20-mo-old wild-type mice. We established that Tif1γ controls TGF-β1 receptor (Tgfbr1) turnover. Compared with young HSCs, Tif1γ(-/-) and old HSCs are more sensitive to TGF-β signaling. Importantly, we identified two populations of HSCs specifically discriminated by Tgfbr1 expression level and provided evidence of the capture of myeloid-biased (Tgfbr1(hi)) and myeloid-lymphoid-balanced (Tgfbr1(lo)) HSCs. In conclusion, our data provide a new paradigm for Tif1γ in regulating the balance between lymphoid- and myeloid-derived HSCs through TGF-β signaling, leading to HSC aging.

  7. Libidibia ferrea Mature Seeds Promote Antinociceptive Effect by Peripheral and Central Pathway: Possible Involvement of Opioid and Cholinergic Receptors

    Directory of Open Access Journals (Sweden)

    Luis Armando Sawada

    2014-01-01

    Full Text Available Libidibia ferrea (LF is a medicinal plant that holds many pharmacological properties. We evaluated the antinociceptive effect in the LF aqueous seed extract and Lipidic Portion of Libidibia ferrea (LPLF, partially elucidating their mechanisms. Histochemical tests and Gas chromatography of the LPLF were performed to characterize its fatty acids. Acetic acid-induced abdominal constriction, formalin-induced pain, and hot-plate test in mice were employed in the study. In all experiments, aqueous extract or LPLF was administered systemically at the doses of 1, 5, and 10 mg/kg. LF aqueous seed extract and LPLF demonstrated a dose-dependent antinociceptive effect in all tests indicating both peripheral anti-inflammatory and central analgesia properties. Also, the use of atropine (5 mg/kg, naloxone (5 mg/kg in the abdominal writhing test was able to reverse the antinociceptive effect of the LPLF, indicating that at least one of LF lipids components is responsible for the dose related antinociceptive action in chemical and thermal models of nociception in mice. Together, the present results suggested that Libidibia ferrea induced antinociceptive activity is possibly related to its ability to inhibit opioid, cholinergic receptors, and cyclooxygenase-2 pathway, since its main component, linoleic acid, has been demonstrated to produce such effect in previous studies.

  8. Immunoglobulin Fc gamma receptor promotes immunoglobulin uptake, immunoglobulin-mediated calcium increase, and neurotransmitter release in motor neurons

    Science.gov (United States)

    Mohamed, Habib A.; Mosier, Dennis R.; Zou, Ling L.; Siklos, Laszlo; Alexianu, Maria E.; Engelhardt, Jozsef I.; Beers, David R.; Le, Wei-dong; Appel, Stanley H.

    2002-01-01

    Receptors for the Fc portion of immunoglobulin G (IgG; FcgammaRs) facilitate IgG uptake by effector cells as well as cellular responses initiated by IgG binding. In earlier studies, we demonstrated that amyotrophic lateral sclerosis (ALS) patient IgG can be taken up by motor neuron terminals and transported retrogradely to the cell body and can alter the function of neuromuscular synapses, such as increasing intracellular calcium and spontaneous transmitter release from motor axon terminals after passive transfer. In the present study, we examined whether FcgammaR-mediated processes can contribute to these effects of ALS patient immunoglobulins. F(ab')(2) fragments (which lack the Fc portion) of ALS patient IgG were not taken up by motor axon terminals and were not retrogradely transported. Furthermore, in a genetically modified mouse lacking the gamma subunit of the FcR, the uptake of whole ALS IgG and its ability to enhance intracellular calcium and acetylcholine release were markedly attenuated. These data suggest that FcgammaRs appear to participate in IgG uptake into motor neurons as well as IgG-mediated increases in intracellular calcium and acetylcholine release from motor axon terminals. Copyright 2002 Wiley-Liss, Inc.

  9. Depletion of retinoic acid receptors initiates a novel positive feedback mechanism that promotes teratogenic increases in retinoic acid.

    Directory of Open Access Journals (Sweden)

    Enrico D'Aniello

    Full Text Available Normal embryonic development and tissue homeostasis require precise levels of retinoic acid (RA signaling. Despite the importance of appropriate embryonic RA signaling levels, the mechanisms underlying congenital defects due to perturbations of RA signaling are not completely understood. Here, we report that zebrafish embryos deficient for RA receptor αb1 (RARαb1, a conserved RAR splice variant, have enlarged hearts with increased cardiomyocyte (CM specification, which are surprisingly the consequence of increased RA signaling. Importantly, depletion of RARαb2 or concurrent depletion of RARαb1 and RARαb2 also results in increased RA signaling, suggesting this effect is a broader consequence of RAR depletion. Concurrent depletion of RARαb1 and Cyp26a1, an enzyme that facilitates degradation of RA, and employment of a novel transgenic RA sensor line support the hypothesis that the increases in RA signaling in RAR deficient embryos are the result of increased embryonic RA coupled with compensatory RAR expression. Our results support an intriguing novel mechanism by which depletion of RARs elicits a previously unrecognized positive feedback loop that can result in developmental defects due to teratogenic increases in embryonic RA.

  10. Smooth muscle LDL receptor-related protein-1 deletion induces aortic insufficiency and promotes vascular cardiomyopathy in mice.

    Directory of Open Access Journals (Sweden)

    Joshua E Basford

    Full Text Available Valvular disease is common in patients with Marfan syndrome and can lead to cardiomyopathy. However, some patients develop cardiomyopathy in the absence of hemodynamically significant valve dysfunction, suggesting alternative mechanisms of disease progression. Disruption of LDL receptor-related protein-1 (Lrp1 in smooth muscle cells has been shown to cause vascular pathologies similar to Marfan syndrome, with activation of smooth muscle cells, vascular dysfunction and aortic aneurysms. This study used echocardiography and blood pressure monitoring in mouse models to determine whether inactivation of Lrp1 in vascular smooth muscle leads to cardiomyopathy, and if so, whether the mechanism is a consequence of valvular disease. Hemodynamic changes during treatment with captopril were also assessed. Dilation of aortic roots was observed in young Lrp1-knockout mice and progressed as they aged, whereas no significant aortic dilation was detected in wild type littermates. Diastolic blood pressure was lower and pulse pressure higher in Lrp1-knockout mice, which was normalized by treatment with captopril. Aortic dilation was followed by development of aortic insufficiency and subsequent dilated cardiomyopathy due to valvular disease. Thus, smooth muscle cell Lrp1 deficiency results in aortic dilation and insufficiency that causes secondary cardiomyopathy that can be improved by captopril. These findings provide novel insights into mechanisms of cardiomyopathy associated with vascular activation and offer a new model of valvular cardiomyopathy.

  11. A virus-targeted plant receptor-like kinase promotes cell-to-cell spread of RNAi.

    Science.gov (United States)

    Rosas-Diaz, Tabata; Zhang, Dan; Fan, Pengfei; Wang, Liping; Ding, Xue; Jiang, Yuli; Jimenez-Gongora, Tamara; Medina-Puche, Laura; Zhao, Xinyan; Feng, Zhengyan; Zhang, Guiping; Liu, Xiaokun; Bejarano, Eduardo R; Tan, Li; Zhang, Heng; Zhu, Jian-Kang; Xing, Weiman; Faulkner, Christine; Nagawa, Shingo; Lozano-Duran, Rosa

    2018-02-06

    RNA interference (RNAi) in plants can move from cell to cell, allowing for systemic spread of an antiviral immune response. How this cell-to-cell spread of silencing is regulated is currently unknown. Here, we describe that the C4 protein from Tomato yellow leaf curl virus can inhibit the intercellular spread of RNAi. Using this viral protein as a probe, we have identified the receptor-like kinase (RLK) BARELY ANY MERISTEM 1 (BAM1) as a positive regulator of the cell-to-cell movement of RNAi, and determined that BAM1 and its closest homolog, BAM2, play a redundant role in this process. C4 interacts with the intracellular domain of BAM1 and BAM2 at the plasma membrane and plasmodesmata, the cytoplasmic connections between plant cells, interfering with the function of these RLKs in the cell-to-cell spread of RNAi. Our results identify BAM1 as an element required for the cell-to-cell spread of RNAi and highlight that signaling components have been coopted to play multiple functions in plants.

  12. NR2B-containing NMDA receptors promote neural progenitor cell proliferation through CaMKIV/CREB pathway

    Energy Technology Data Exchange (ETDEWEB)

    Li, Mei, E-mail: limeihit@163.com [Department of Anatomy and Neurobiology, Xuzhou Medical College, Xuzhou (China); Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, Nanjing (China); Zhang, Dong-Qing; Wang, Xiang-Zhen [Department of Anatomy and Neurobiology, Xuzhou Medical College, Xuzhou (China); Xu, Tie-Jun, E-mail: xztjxu@163.com [Department of Anatomy and Neurobiology, Xuzhou Medical College, Xuzhou (China); Jiangsu Key Laboratory of Neurodegeneration, Department of Pharmacology, Nanjing Medical University, Nanjing (China)

    2011-08-12

    Highlights: {yields} The NR2B component of the NMDARs is important for the NSPC proliferation. {yields} pCaMKIV and pCREB exist in NSPCs. {yields} The CaMKIV/CREB pathway mediates NSPC proliferation. -- Abstract: Accumulating evidence indicates the involvement of N-methyl-D-aspartate receptors (NMDARs) in regulating neural stem/progenitor cell (NSPC) proliferation. Functional properties of NMDARs can be markedly influenced by incorporating the regulatory subunit NR2B. Here, we aim to analyze the effect of NR2B-containing NMDARs on the proliferation of hippocampal NSPCs and to explore the mechanism responsible for this effect. NSPCs were shown to express NMDAR subunits NR1 and NR2B. The NR2B selective antagonist, Ro 25-6981, prevented the NMDA-induced increase in cell proliferation. Moreover, we demonstrated that the phosphorylation levels of calcium/calmodulin-dependent protein kinase IV (CaMKIV) and cAMP response element binding protein (CREB) were increased by NMDA treatment, whereas Ro 25-6981 decreased them. The role that NR2B-containing NMDARs plays in NSPC proliferation was abolished when CREB phosphorylation was attenuated by CaMKIV silencing. These results suggest that NR2B-containing NMDARs have a positive role in regulating NSPC proliferation, which may be mediated through CaMKIV phosphorylation and subsequent induction of CREB activation.

  13. The Environmental Neurotoxicant PCB 95 Promotes Synaptogenesis via Ryanodine Receptor-Dependent miR132 Upregulation

    Science.gov (United States)

    Lesiak, Adam; Zhu, Mingyan; Chen, Hao; Appleyard, Suzanne M.; Impey, Soren; Wayman, Gary A.

    2014-01-01

    Non–dioxin-like (NDL) polychlorinated biphenyls (PCBs) are widespread environmental contaminants linked to neuropsychological dysfunction in children. NDL PCBs increase spontaneous Ca2+ oscillations in neurons by stabilizing ryanodine receptor (RyR) calcium release channels in the open configuration, which results in CREB-dependent dendritic outgrowth. In this study, we address the question of whether activation of CREB by NDL PCBs also triggers dendritic spine formation. Nanomolar concentrations of PCB 95, a NDL congener with potent RyR activity, significantly increased spine density and the frequency of miniature EPSCs in primary dissociated rat hippocampal cultures coincident with upregulation of miR132. Inhibition of RyR, CREB, or miR132 as well as expression of a mutant p250GAP cDNA construct that is not suppressed by miR132 blocked PCB 95 effects on spines and miniature EPSCs. PCB 95 also induced spine formation via RyR- and miR132-dependent mechanisms in hippocampal slice cultures. These data demonstrate a novel mechanism of PCB developmental neurotoxicity whereby RyR sensitization modulates spine formation and synaptogenesis via CREB-mediated miR132 upregulation, which in turn suppresses the translation of p250GAP, a negative regulator of synaptogenesis. In light of recent evidence implicating miR132 dysregulation in Rett syndrome and schizophrenia, these findings identify NDL PCBs as potential environmental risk factors for neurodevelopmental disorders. PMID:24431430

  14. T-bet- and STAT4-dependent IL-33 receptor expression directly promotes antiviral Th1 cell responses.

    Science.gov (United States)

    Baumann, Claudia; Bonilla, Weldy V; Fröhlich, Anja; Helmstetter, Caroline; Peine, Michael; Hegazy, Ahmed N; Pinschewer, Daniel D; Löhning, Max

    2015-03-31

    During infection, the release of damage-associated molecular patterns, so-called "alarmins," orchestrates the immune response. The alarmin IL-33 plays a role in a wide range of pathologies. Upon release, IL-33 signals through its receptor ST2, which reportedly is expressed only on CD4(+) T cells of the Th2 and regulatory subsets. Here we show that Th1 effector cells also express ST2 upon differentiation in vitro and in vivo during lymphocytic choriomeningitis virus (LCMV) infection. The expression of ST2 on Th1 cells was transient, in contrast to constitutive ST2 expression on Th2 cells, and marked highly activated effector cells. ST2 expression on virus-specific Th1 cells depended on the Th1-associated transcription factors T-bet and STAT4. ST2 deficiency resulted in a T-cell-intrinsic impairment of LCMV-specific Th1 effector responses in both mixed bone marrow-chimeric mice and adoptive cell transfer experiments. ST2-deficient virus-specific CD4(+) T cells showed impaired expansion, Th1 effector differentiation, and antiviral cytokine production. Consequently, these cells mediated little virus-induced immunopathology. Thus, IL-33 acts as a critical and direct cofactor to drive antiviral Th1 effector cell activation, with implications for vaccination strategies and immunotherapeutic approaches.

  15. Libidibia ferrea mature seeds promote antinociceptive effect by peripheral and central pathway: possible involvement of opioid and cholinergic receptors.

    Science.gov (United States)

    Sawada, Luis Armando; Monteiro, Vanessa Sâmia da Conçeição; Rabelo, Guilherme Rodrigues; Dias, Germana Bueno; Da Cunha, Maura; do Nascimento, José Luiz Martins; Bastos, Gilmara de Nazareth Tavares

    2014-01-01

    Libidibia ferrea (LF) is a medicinal plant that holds many pharmacological properties. We evaluated the antinociceptive effect in the LF aqueous seed extract and Lipidic Portion of Libidibia ferrea (LPLF), partially elucidating their mechanisms. Histochemical tests and Gas chromatography of the LPLF were performed to characterize its fatty acids. Acetic acid-induced abdominal constriction, formalin-induced pain, and hot-plate test in mice were employed in the study. In all experiments, aqueous extract or LPLF was administered systemically at the doses of 1, 5, and 10 mg/kg. LF aqueous seed extract and LPLF demonstrated a dose-dependent antinociceptive effect in all tests indicating both peripheral anti-inflammatory and central analgesia properties. Also, the use of atropine (5 mg/kg), naloxone (5 mg/kg) in the abdominal writhing test was able to reverse the antinociceptive effect of the LPLF, indicating that at least one of LF lipids components is responsible for the dose related antinociceptive action in chemical and thermal models of nociception in mice. Together, the present results suggested that Libidibia ferrea induced antinociceptive activity is possibly related to its ability to inhibit opioid, cholinergic receptors, and cyclooxygenase-2 pathway, since its main component, linoleic acid, has been demonstrated to produce such effect in previous studies.

  16. I prostanoid receptor-mediated inflammatory pathway promotes hepatic gluconeogenesis through activation of PKA and inhibition of AKT.

    Science.gov (United States)

    Yan, Shuai; Zhang, Qianqian; Zhong, Xiaojing; Tang, Juan; Wang, Yuanyang; Yu, Junjie; Zhou, Yi; Zhang, Jian; Guo, Feifan; Liu, Yi; FitzGerald, Garret A; Yu, Ying

    2014-09-01

    Nonsteroidal anti-inflammatory drugs (NSAIDs), including acetylsalicylic acid (ASA), improve glucose metabolism in diabetic subjects, although the underlying mechanisms remain unclear. In this study, we observed dysregulated expression of cyclooxygenase-2, prostacyclin biosynthesis, and the I prostanoid receptor (IP) in the liver's response to diabetic stresses. High doses of ASA reduced hepatic prostaglandin generation and suppressed hepatic gluconeogenesis in mice during fasting, and the hypoglycemic effect of ASA could be restored by IP agonist treatment. IP deficiency inhibited starvation-induced hepatic gluconeogenesis, thus inhibiting the progression of diabetes, whereas hepatic overexpression of IP increased gluconeogenesis. IP deletion depressed cAMP-dependent CREB phosphorylation and elevated AKT phosphorylation by suppressing PI3K-γ/PKC-ζ-mediated TRB3 expression, which subsequently downregulated the gluconeogenic genes for glucose-6-phosphatase (G6Pase) and phosphoenol pyruvate carboxykinase 1 in hepatocytes. We therefore conclude that suppression of IP modulation of hepatic gluconeogenesis through the PKA/CREB and PI3K-γ/PKC-ζ/TRB3/AKT pathways contributes to the effects of NSAIDs in diabetes. © 2014 by the American Diabetes Association. Readers may use this article as long as the work is properly cited, the use is educational and not for profit, and the work is not altered.

  17. Proteoglycan from salmon nasal cartridge promotes in vitro wound healing of fibroblast monolayers via the CD44 receptor

    Energy Technology Data Exchange (ETDEWEB)

    Ito, Gen; Kobayashi, Takeshi; Takeda, Yoshie [Department of Physiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550 (Japan); Sokabe, Masahiro, E-mail: msokabe@med.nagoya-u.ac.jp [Department of Physiology, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550 (Japan); Mechanobiology Laboratory, Nagoya University Graduate School of Medicine, Nagoya, Aichi 466-8550 (Japan); Mechanobiology Institute Singapore, National University of Singapore, Singapore 117411 (Singapore)

    2015-01-16

    Highlights: • Proteoglycan from salmon nasal cartridge (SNC-PG) promoted wound healing in fibroblast monolayers. • SNC-PG stimulated both cell proliferation and cell migration. • Interaction between chondroitin sulfate-units and CD44 is responsible for the effect. - Abstract: Proteoglycans (PGs) are involved in various cellular functions including cell growth, adhesion, and differentiation; however, their physiological roles are not fully understood. In this study, we examined the effect of PG purified from salmon nasal cartilage (SNC-PG) on wound closure using tissue-cultured cell monolayers, an in vitro wound-healing assay. The results indicated that SNC-PG significantly promoted wound closure in NIH/3T3 cell monolayers by stimulating both cell proliferation and cell migration. SNC-PG was effective in concentrations from 0.1 to 10 μg/ml, but showed much less effect at higher concentrations (100–1000 μg/ml). The effect of SNC-PG was abolished by chondroitinase ABC, indicating that chondroitin sulfates (CSs), a major component of glycosaminoglycans (GAGs) in SNC-PG, are crucial for the SNC-PG effect. Furthermore, chondroitin 6-sulfate (C-6-S), a major CS of SNC-PG GAGs, could partially reproduce the SNC-PG effect and partially inhibit the binding of SNC-PG to cells, suggesting that SNC-PG exerts its effect through an interaction between the GAGs in SNC-PG and the cell surface. Neutralization by anti-CD44 antibodies or CD44 knockdown abolished SNC-PG binding to the cells and the SNC-PG effect on wound closure. These results suggest that interactions between CS-rich GAG-chains of SNC-PG and CD44 on the cell surface are responsible for the SNC-PG effect on wound closure.

  18. The activating receptor NKG2D of natural killer cells promotes resistance against enterovirus-mediated inflammatory cardiomyopathy.

    Science.gov (United States)

    Klingel, Karin; Fabritius, Cornelia; Sauter, Martina; Göldner, Katrin; Stauch, Diana; Kandolf, Reinhard; Ettischer, Nicole; Gahlen, Sabine; Schönberger, Tanja; Ebner, Susanne; Makrigiannis, Andrew P; Bélanger, Simon; Diefenbach, Andreas; Polić, Bojan; Pratschke, Johann; Kotsch, Katja

    2014-10-01

    In enterovirus-induced cardiomyopathy, information regarding the detailed impact of natural killer (NK) cells on the outcome of the disease is limited. We therefore hypothesized that NK cells and certain NK cell receptors determine the different outcome of coxsackievirus B3 (CVB3) myocarditis. Here, we demonstrate in murine models that resistance to chronic CVB3 myocarditis in immunocompetent C57BL/6 mice is characterized by significantly more mature CD11b(high) NK cells, the presence of NKG2D on NK cells, and enhanced NKG2D-dependent cytotoxicity compared to CVB3-susceptible A.BY/SnJ mice. The highly protective role of NKG2D in myocarditis was further proven by in vivo neutralization of NKG2D as well as in NKG2D-deficient mice but was shown to be independent of CD8(+) T-cell-dependent immunity. Moreover, the adoptive transfer of immunocompetent C57BL/6 NK cells pre- (day -1) as well as post-infectionem (day +2) displayed the potential to prevent permissive A.BY/SnJ mice from a progressive outcome of CVB3 myocarditis reflected by significantly improved cardiopathology and heart function. Altogether, our results provide firm evidence for a protective role of NKG2D-activated NK cells in CVB3 myocarditis leading to an effective virus clearance, thus offering novel therapeutic options in the treatment of virus-induced myocarditis. Copyright © 2014 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  19. Steroid receptor coactivator-2 (SRC-2) coordinates cardiomyocyte paracrine signaling to promote pressure overload-induced angiogenesis.

    Science.gov (United States)

    Suh, Ji Ho; Lai, Li; Nam, Deokhwa; Kim, Jong; Jo, Juyeon; Taffet, George E; Kim, Eunah; Kaelber, Jason T; Lee, Hyun-Kyoung; Entman, Mark L; Cooke, John P; Reineke, Erin L

    2017-12-29

    Pressure overload-induced cardiac stress induces left ventricular hypertrophy driven by increased cardiomyocyte mass. The increased energetic demand and cardiomyocyte size during hypertrophy necessitate increased fuel and oxygen delivery and stimulate angiogenesis in the left ventricular wall. We have previously shown that the transcriptional regulator steroid receptor coactivator-2 (SRC-2) controls activation of several key cardiac transcription factors and that SRC-2 loss results in extensive cardiac transcriptional remodeling. Pressure overload in mice lacking SRC-2 induces an abrogated hypertrophic response and decreases sustained cardiac function, but the cardiomyocyte-specific effects of SRC-2 in these changes are unknown. Here, we report that cardiomyocyte-specific loss of SRC-2 (SRC-2 CKO) results in a blunted hypertrophy accompanied by a rapid, progressive decrease in cardiac function. We found that SRC-2 CKO mice exhibit markedly decreased left ventricular vasculature in response to transverse aortic constriction, corresponding to decreased expression of the angiogenic factor VEGF. Of note, SRC-2 knockdown in cardiomyocytes decreased VEGF expression and secretion to levels sufficient to blunt in vitro tube formation and proliferation of endothelial cells. During pressure overload, both hypertrophic and hypoxic signals can stimulate angiogenesis, both of which stimulated SRC-2 expression in vitro Furthermore, SRC-2 coactivated the transcription factors GATA-binding protein 4 (GATA-4) and hypoxia-inducible factor (HIF)-1α and -2α in response to angiotensin II and hypoxia, respectively, which drive VEGF expression. These results suggest that SRC-2 coordinates cardiomyocyte secretion of VEGF downstream of the two major angiogenic stimuli occurring during pressure overload bridging both hypertrophic and hypoxia-stimulated paracrine signaling. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  20. The chemokine CXCL16 and its receptor, CXCR6, as markers and promoters of inflammation-associated cancers.

    Directory of Open Access Journals (Sweden)

    Merav Darash-Yahana

    2009-08-01

    Full Text Available Clinical observations and mouse models have suggested that inflammation can be pro-tumorigenic. Since chemokines are critical in leukocyte trafficking, we hypothesized that chemokines play essential roles in inflammation-associated cancers. Screening for 37 chemokines in prostate cancer cell lines and xenografts revealed CXCL16, the ligand for the receptor CXCR6, as the most consistently expressed chemokine. Immunohistochemistry and/or immunofluorescence and confocal imaging of 121 human prostate specimens showed that CXCL16 and CXCR6 were co-expressed, both on prostate cancer cells and adjacent T cells. Expression levels of CXCL16 and CXCR6 on cancer cells correlated with poor prognostic features including high-stage and high-grade, and expression also correlated with post-inflammatory changes in the cancer stroma as revealed by loss of alpha-smooth muscle actin. Moreover, CXCL16 enhanced the growth of CXCR6-expressing cancer and primary CD4 T cells. We studied expression of CXCL16 in an additional 461 specimens covering 12 tumor types, and found that CXCL16 was expressed in multiple human cancers associated with inflammation. Our study is the first to describe the expression of CXCL16/CXCR6 on both cancer cells and adjacent T cells in humans, and to demonstrate correlations between CXCL16 and CXCR6 vs. poor both prognostic features and reactive changes in cancer stoma. Taken together, our data suggest that CXCL16 and CXCR6 may mark cancers arising in an inflammatory milieu and mediate pro-tumorigenic effects of inflammation through direct effects on cancer cell growth and by inducing the migration and proliferation of tumor-associated leukocytes.

  1. Short term morphine exposure in vitro alters proliferation and differentiation of neural progenitor cells and promotes apoptosis via mu receptors.

    Directory of Open Access Journals (Sweden)

    Dafna Willner

    Full Text Available Chronic morphine treatment inhibits neural progenitor cell (NPC progression and negatively effects hippocampal neurogenesis. However, the effect of acute opioid treatment on cell development and its influence on NPC differentiation and proliferation in vitro is unknown. We aim to investigate the effect of a single, short term exposure of morphine on the proliferation, differentiation and apoptosis of NPCs and the mechanism involved.Cell cultures from 14-day mouse embryos were exposed to different concentrations of morphine and its antagonist naloxone for 24 hours and proliferation, differentiation and apoptosis were studied. Proliferating cells were labeled with bromodeoxyuridine (BrdU and cell fate was studied with immunocytochemistry.Cells treated with morphine demonstrated decreased BrdU expression with increased morphine concentrations. Analysis of double-labeled cells showed a decrease in cells co-stained for BrdU with nestin and an increase in cells co-stained with BrdU and neuron-specific class III β-tubuline (TUJ1 in a dose dependent manner. Furthermore, a significant increase in caspase-3 activity was observed in the nestin- positive cells. Addition of naloxone to morphine-treated NPCs reversed the anti-proliferative and pro-apoptotic effects of morphine.Short term morphine exposure induced inhibition of NPC proliferation and increased active caspase-3 expression in a dose dependent manner. Morphine induces neuronal and glial differentiation and decreases the expression of nestin- positive cells. These effects were reversed with the addition of the opioid antagonist naloxone. Our results demonstrate the effects of short term morphine administration on the proliferation and differentiation of NPCs and imply a mu-receptor mechanism in the regulation of NPC survival.

  2. Stimulation of the toll-like receptor 3 promotes metabolic reprogramming in head and neck carcinoma cells.

    Science.gov (United States)

    Veyrat, Mathieu; Durand, Sylvère; Classe, Marion; Glavan, Tanja Matijevic; Oker, Natalie; Kapetanakis, Nikiforos-Ioannis; Jiang, Xiaojun; Gelin, Aurore; Herman, Philippe; Casiraghi, Odile; Zagzag, David; Enot, David; Busson, Pierre; Vérillaud, Benjamin

    2016-12-13

    In this study, a possible link between the innate immune recognition receptor TLR3 and metabolic reprogramming in Head and Neck carcinoma (HNC) cells was investigated. The effects of TLR3 stimulation/knock-down were assessed under several culture conditions in 4 HNC cell-lines by cell growth assays, targeted metabolomics, and glycolysis assays based on time-resolved analysis of proton release (Seahorse analyzer). The stimulation of TLR3 by its synthetic agonist Poly(A:U) resulted in a faster growth of HNC cells under low foetal calf serum conditions. Targeted analysis of glucose metabolism pathways demonstrated a tendency towards a shift from tricarboxylic acid cycle (Krebs cycle) to glycolysis and anabolic reactions in cells treated with Poly(A:U). Glycolysis assays confirmed that TLR3 stimulation enhanced the capacity of malignant cells to switch from oxidative phosphorylation to extra-mitochondrial glycolysis. We found evidence that HIF-1α is involved in this process: addition of the TLR3 agonist resulted in a higher cell concentration of the HIF-1α protein, even in normoxia, whereas knocking-down TLR3 resulted in a lower concentration, even in hypoxia. Finally, we assessed TLR3 expression by immunohistochemistry in a series of 7 HNSCC specimens and found that TLR3 was detected at higher levels in tumors displaying a hypoxic staining pattern. Overall, our results demonstrate that TLR3 stimulation induces the Warburg effect in HNC cells in vitro, and suggest that TLR3 may play a role in tumor adaptation to hypoxia.

  3. Src promotes castration-recurrent prostate cancer through androgen receptor-dependent canonical and non-canonical transcriptional signatures.

    Science.gov (United States)

    Chattopadhyay, Indranil; Wang, Jianmin; Qin, Maochun; Gao, Lingqiu; Holtz, Renae; Vessella, Robert L; Leach, Robert W; Gelman, Irwin H

    2017-02-07

    Progression of prostate cancer (PC) to castration-recurrent growth (CRPC) remains dependent on sustained expression and transcriptional activity of the androgen receptor (AR). A major mechanism contributing to CRPC progression is through the direct phosphorylation and activation of AR by Src-family (SFK) and ACK1 tyrosine kinases. However, the AR-dependent transcriptional networks activated by Src during CRPC progression have not been elucidated. Here, we show that activated Src (Src527F) induces androgen-independent growth in human LNCaP cells, concomitant with its ability to induce proliferation/survival genes normally induced by dihydrotestosterone (DHT) in androgen-dependent LNCaP and VCaP cells. Src induces additional gene signatures unique to CRPC cell lines, LNCaP-C4-2 and CWR22Rv1, and to CRPC LuCaP35.1 xenografts. By comparing the Src-induced AR-cistrome and/or transcriptome in LNCaP to those in CRPC and LuCaP35.1 tumors, we identified an 11-gene Src-regulated CRPC signature consisting of AR-dependent, AR binding site (ARBS)-associated genes whose expression is altered by DHT in LNCaP[Src527F] but not in LNCaP cells. The differential expression of a subset (DPP4, BCAT1, CNTNAP4, CDH3) correlates with earlier PC metastasis onset and poorer survival, with the expression of BCAT1 required for Src-induced androgen-independent proliferation. Lastly, Src enhances AR binding to non-canonical ARBS enriched for FOXO1, TOP2B and ZNF217 binding motifs; cooperative AR/TOP2B binding to a non-canonical ARBS was both Src- and DHT-sensitive and correlated with increased levels of Src-induced phosphotyrosyl-TOP2B. These data suggest that CRPC progression is facilitated via Src-induced sensitization of AR to intracrine androgen levels, resulting in the engagement of canonical and non-canonical ARBS-dependent gene signatures.

  4. OCT-4: a novel estrogen receptor-α collaborator that promotes tamoxifen resistance in breast cancer cells.

    Science.gov (United States)

    Bhatt, S; Stender, J D; Joshi, S; Wu, G; Katzenellenbogen, B S

    2016-11-03

    Tamoxifen has shown great success in the treatment of breast cancer; however, long-term treatment can lead to acquired tamoxifen (TOT) resistance and relapse. TOT classically antagonizes estradiol (E2) -dependent breast cancer cell growth, but exerts partial agonist/antagonist behavior on gene expression. Although both E2 and TOT treatment of breast cancer cells results in recruitment of the estrogen receptor (ER) to common and distinct genomic sites, the mechanisms and proteins underlying TOT preferential recruitment of the ER remains poorly defined. To this end, we performed in silico motif-enrichment analyses within the ER-binding peaks in response to E2 or TOT, to identify factors that would specifically recruit ER to genomic binding sites in the presence of TOT as compared to E2. Intriguingly, we found Nkx3-1 and Oct-transcription factor homodimer motifs to be enriched in TOT preferential binding sites and confirmed the critical role of Oct-3/4 (aka Oct-4) in directing ER recruitment to TOT preferential genomic binding sites, by chromatin immunoprecipitation (ChIP) analyses. Further investigation revealed Oct-4 expression to be basally repressed by Nkx3-1 in MCF-7 cells and TOT treatment appeared to elevate Nkx3-1 degradation through a p38MAPK-dependent phosphorylation of the E3 ligase, Skp2 at serine-64 residue, as observed by quantitative mass-spectrometry analyses. Consistently, Oct-4 upon induction by phospho-Ser64-Skp2-mediated proteasomal degradation of Nkx3-1, participated in ER transcriptional complexes along with p38MAPK and Skp2 in a tamoxifen-dependent manner leading to TOT-dependent gene activation and cell proliferation of the TOT-resistant MCF-7-tam r breast cancer cells. Notably, Oct-4 levels were highly elevated in MCF-7-tam r cells, and appeared critical for their TOT sensitivity in cell proliferation assays. Furthermore, overexpression of Oct-4 enhanced tumor growth in the presence of tamoxifen in mice in vivo. Collectively, our work presents

  5. Myoinositol ameliorates high-fat diet and streptozotocin-induced diabetes in rats through promoting insulin receptor signaling.

    Science.gov (United States)

    Antony, Poovathumkal James; Gandhi, Gopalsamy Rajiv; Stalin, Antony; Balakrishna, Kedike; Toppo, Erenius; Sivasankaran, Kuppusamy; Ignacimuthu, Savarimuthu; Al-Dhabi, Naif Abdullah

    2017-04-01

    Mimosa pudica Linn. (Mimosaceae) has been traditionally used for the management of type 2 diabetes mellitus (T2DM) in India. The present study evaluates the therapeutic efficacy of myoinositol (25 and 50mg/kg) isolated from M. pudica stem methanol extract in Triton WR-1339 induced hyperlipidemic and high-fat diet (HFD) fed-streptozotocin (STZ)-induced insulin-resistant diabetic rats. Lipid biomarkers, fasting blood glucose (FBG), changes in body weight, food and water intakes, plasma insulin, HOMA-IR, oral glucose tolerance, intraperitoneal insulin tolerance, urea, creatinine, marker enzymes of liver function, β-cell function and the expression levels of insulin receptor-induced signaling molecules were studied. Molecular-docking was also carried out to determine the possible interactions of myoinositol into the active sites of insulin-induced signaling markers. In addition, histology of liver, pancreas, kidney, heart and adipose tissues were also performed. In Triton WR-1339 induced hyperlipidemic rats, myoinositol (25 and 50mg/kg) exhibited significant reductions in total cholesterol: 37.5% and 59.73%, triglycerides: 57.75% and 80.14% and LDL-c: 81.44% and 101.75% respectively. HFD fed-STZ receiving myoinositol (25 and 50mg/kg) showed significant reductions in fasting blood glucose: 55.68% and 56.48%, plasma insulin level: 25.45% and 27.06% when compared with diabetic control. It significantly normalized the hyperglycemia induced biochemical abnormalities in insulin-resistant diabetic rats. Furthermore, it demonstrated cytoprotective effects besides increase in the intensity of positive reaction for insulin in pancreas. Myoinositol enhanced the level of PPARγ expression in the adipose tissue of treated rats when compared with rats that did not receive drug treatment; also, it significantly upregulated GLUT4 and IR signaling molecules. Myoinositol had predicted the interactions within the active sites of PPARγ, GLUT4 and IR. These findings suggested that

  6. The G Protein-Coupled Estrogen Receptor-1, GPER-1, Promotes Fibrillogenesis via a Shc-Dependent Pathway Resulting in Anchorage-Independent Growth

    Science.gov (United States)

    Magruder, Hilary T.; Quinn, Jeffrey A.; Schwartzbauer, Jean E.; Reichner, Jonathan; Huang, Allan

    2016-01-01

    The G protein-coupled estrogen receptor-1, GPER-1, coordinates fibronectin (FN) matrix assembly and release of heparan-bound epidermal growth factor (HB-EGF). This mechanism of action results in the recruitment of FN-engaged integrin α5β1 to fibrillar adhesions and the formation of integrin α5β1-Shc adaptor protein complexes. Here, we show that GPER-1 stimulation of murine 4 T1 or human SKBR3 breast cancer cells with 17β-estradiol (E2β) promotes the formation of focal adhesions and actin stress fibers and results in increased cellular adhesion and haptotaxis on FN, but not collagen. These actions are also induced by the xenoestrogen, bisphenol A, and the estrogen receptor (ER) antagonist, ICI 182, 780, but not the inactive stereoisomer, 17α-estradiol (E2α). In addition, we show that GPER-1 stimulation of breast cancer cells allows for FN-dependent, anchorage-independent growth and FN fibril formation in “hanging drop” assays, indicating that these GPER-1-mediated actions occur independently of adhesion to solid substrata. Stable expression of Shc mutant Y317F lacking its primary tyrosyl phosphorylation site disrupts E2β-induced focal adhesion and actin stress fiber formation and abolishes E2β-enhanced haptotaxis on FN and anchorage-dependent growth. Collectively, these data demonstrate that E2β action via GPER-1 enhances cellular adhesivity and FN matrix assembly and allows for anchorage-independent growth, cellular events that may allow for cellular survival, and tumor progression. PMID:25096985

  7. A Novel Small Molecule GDNF Receptor RET Agonist, BT13, Promotes Neurite Growth from Sensory Neurons in Vitro and Attenuates Experimental Neuropathy in the Rat

    Directory of Open Access Journals (Sweden)

    Yulia A. Sidorova

    2017-06-01

    Full Text Available Neuropathic pain caused by nerve damage is a common and severe class of chronic pain. Disease-modifying clinical therapies are needed as current treatments typically provide only symptomatic relief; show varying clinical efficacy; and most have significant adverse effects. One approach is targeting either neurotrophic factors or their receptors that normalize sensory neuron function and stimulate regeneration after nerve damage. Two candidate targets are glial cell line-derived neurotrophic factor (GDNF and artemin (ARTN, as these GDNF family ligands (GFLs show efficacy in animal models of neuropathic pain (Boucher et al., 2000; Gardell et al., 2003; Wang et al., 2008, 2014. As these protein ligands have poor drug-like properties and are expensive to produce for clinical use, we screened 18,400 drug-like compounds to develop small molecules that act similarly to GFLs (GDNF mimetics. This screening identified BT13 as a compound that selectively targeted GFL receptor RET to activate downstream signaling cascades. BT13 was similar to NGF and ARTN in selectively promoting neurite outgrowth from the peptidergic class of adult sensory neurons in culture, but was opposite to ARTN in causing neurite elongation without affecting initiation. When administered after spinal nerve ligation in a rat model of neuropathic pain, 20 and 25 mg/kg of BT13 decreased mechanical hypersensitivity and normalized expression of sensory neuron markers in dorsal root ganglia. In control rats, BT13 had no effect on baseline mechanical or thermal sensitivity, motor coordination, or weight gain. Thus, small molecule BT13 selectively activates RET and offers opportunities for developing novel disease-modifying medications to treat neuropathic pain.

  8. A Novel Small Molecule GDNF Receptor RET Agonist, BT13, Promotes Neurite Growth from Sensory Neuronsin Vitroand Attenuates Experimental Neuropathy in the Rat.

    Science.gov (United States)

    Sidorova, Yulia A; Bespalov, Maxim M; Wong, Agnes W; Kambur, Oleg; Jokinen, Viljami; Lilius, Tuomas O; Suleymanova, Ilida; Karelson, Gunnar; Rauhala, Pekka V; Karelson, Mati; Osborne, Peregrine B; Keast, Janet R; Kalso, Eija A; Saarma, Mart

    2017-01-01

    Neuropathic pain caused by nerve damage is a common and severe class of chronic pain. Disease-modifying clinical therapies are needed as current treatments typically provide only symptomatic relief; show varying clinical efficacy; and most have significant adverse effects. One approach is targeting either neurotrophic factors or their receptors that normalize sensory neuron function and stimulate regeneration after nerve damage. Two candidate targets are glial cell line-derived neurotrophic factor (GDNF) and artemin (ARTN), as these GDNF family ligands (GFLs) show efficacy in animal models of neuropathic pain (Boucher et al., 2000; Gardell et al., 2003; Wang et al., 2008, 2014). As these protein ligands have poor drug-like properties and are expensive to produce for clinical use, we screened 18,400 drug-like compounds to develop small molecules that act similarly to GFLs (GDNF mimetics). This screening identified BT13 as a compound that selectively targeted GFL receptor RET to activate downstream signaling cascades. BT13 was similar to NGF and ARTN in selectively promoting neurite outgrowth from the peptidergic class of adult sensory neurons in culture, but was opposite to ARTN in causing neurite elongation without affecting initiation. When administered after spinal nerve ligation in a rat model of neuropathic pain, 20 and 25 mg/kg of BT13 decreased mechanical hypersensitivity and normalized expression of sensory neuron markers in dorsal root ganglia. In control rats, BT13 had no effect on baseline mechanical or thermal sensitivity, motor coordination, or weight gain. Thus, small molecule BT13 selectively activates RET and offers opportunities for developing novel disease-modifying medications to treat neuropathic pain.

  9. Lack of c-kit receptor promotes mammary tumors in N-nitrosomethylurea-treated Ws/Ws rats

    Directory of Open Access Journals (Sweden)

    Papadopoulos Nikoletta

    2008-04-01

    Full Text Available Abstract Background c-kit is expressed in various cell types during development and it has been linked to the promotion of cellular migration, proliferation and/or survival of melanoblasts, hematopoietic progenitors and primordial germ cells. Several reports have proposed a role for the c-kit gene on carcinogenesis. Gain-of-function mutations are associated with diseases such as mastocytosis and gastrointestinal stromal tumors among others. However, very little is known about pathologies associated with loss-of-function mutations. Regarding breast cancer, c-kit protein and mRNA are highly expressed in normal breast but their expression decreases or is absent in the presence of breast cancer. We studied the role of c-kit in mammary carcinogenesis in the Ws/Ws rats carrying spontaneous lack-of-function mutation in the c-kit gene. Fifty day-old virgin female Ws/Ws rats and their wild type counterparts were injected with either 50 mg/kg body weight of the chemical carcinogen N-nitrosomethylurea or with vehicle. The animals were followed-up for 6 months. Fisher 344 rats were used as positive controls for tumor development. Results Eleven weeks after treatment, palpable tumors were detected in the Ws/Ws rats. The tumor incidence was 80% in Ws/Ws rats, while no tumors were observed in the wild type rats (p = 0.006. Our data show that the lack of c-kit is permissive for the development of mammary tumor in Ws/Ws rats treated with carcinogen. Conclusion We conclude that the lack of c-kit may contribute to an imbalanced homeostatic state in the mammary gland either by affecting signaling between stroma and epithelium, or through the lack of mast cells.

  10. miR-221/222 targets adiponectin receptor 1 to promote the epithelial-to-mesenchymal transition in breast cancer.

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    Michael S Hwang

    Full Text Available The epithelial-to-mesenchymal transition (EMT is a highly conserved physiological program involved in development and tissue repair; however, its aberrant activation has been implicated in accelerating the progression of a variety of cancers. In breast cancer, the microRNAs (miRNAs miR-221 and miR-222 (miR-221/222 are differentially expressed in the clinically more aggressive basal-like subtype compared to luminal subtype of breast cancer and upregulation of miR-221/222 induces the EMT by targeting the 3' untranslated region (3'UTR of the GATA family transcriptional repressor TRPS1 (tricho-rhino-phalangeal syndrome type 1. The complete mechanism through which miR-221/222 promotes the EMT, however, is not fully understood. We identified adiponectin receptor 1 (ADIPOR1, a receptor for the adipocytokine adiponectin, as a direct target of miR-221/222. ADIPOR1 is expressed at higher levels in the luminal compared to the basal-like subtype of breast cancer cell lines, which can be reduced by miR-221/222 targeting of its 3'UTR. In addition, miR-221/222 were negatively correlated with ADIPOR1 expression across breast cancer cell lines and tumors. ADIPOR1 depletion by siRNA in MCF10A cells induced the EMT and increased cell invasion. Depletion of ADIPOR1 by siRNA induced activation of the canonical nuclear factor-kappaB (NF-κB and subsequent phosphorylation of signal transducer and activator of transcription 3 (STAT3 in an interleukin 6 (IL6-dependent manner. Finally, overexpression of ADIPOR1 in the basal-like cell line, MDA-MB-231, attenuated cell invasion and promoted the mesenchymal-to-epithelial transition (MET. We conclude that ADIPOR1 negatively regulates EMT in breast cancer and provides an additional node by which miR-221/222 induces the EMT. These results suggest that ADIPOR1 may play an important role in breast cancer progression and metastasis, and could potentially offer an alternative therapeutic strategy for basal-like breast cancer

  11. Mechanical Vibration Mitigates the Decrease of Bone Quantity and Bone Quality of Leptin Receptor-Deficient Db/Db Mice by Promoting Bone Formation and Inhibiting Bone Resorption.

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    Jing, Da; Luo, Erping; Cai, Jing; Tong, Shichao; Zhai, Mingming; Shen, Guanghao; Wang, Xin; Luo, Zhuojing

    2016-09-01

    Leptin, a major hormonal product of adipocytes, is involved in regulating appetite and energy metabolism. Substantial studies have revealed the anabolic actions of leptin on skeletons and bone cells both in vivo and in vitro. Growing evidence has substantiated that leptin receptor-deficient db/db mice exhibit decreased bone mass and impaired bone microstructure despite several conflicting results previously reported. We herein systematically investigated bone microarchitecture, mechanical strength, bone turnover and its potential molecular mechanisms in db/db mice. More importantly, we also explored an effective approach for increasing bone mass in leptin receptor-deficient animals in an easy and noninvasive manner. Our results show that deterioration of trabecular and cortical bone microarchitecture and decreases of skeletal mechanical strength-including maximum load, yield load, stiffness, energy, tissue-level modulus and hardness-in db/db mice were significantly ameliorated by 12-week, whole-body vibration (WBV) with 0.5 g, 45 Hz via micro-computed tomography (μCT), three-point bending, and nanoindentation examinations. Serum biochemical analysis shows that WBV significantly decreased serum tartrate-resistant acid phosphatase 5b (TRACP5b) and CTx-1 levels and also mitigated the reduction of serum osteocalcin (OCN) in db/db mice. Bone histomorphometric analysis confirmed that decreased bone formation-lower mineral apposition rate, bone formation rate, and osteoblast numbers in cancellous bone-in db/db mice were suppressed by WBV. Real-time PCR assays show that WBV mitigated the reductions of tibial alkaline phosphatase (ALP), OCN, Runt-related transcription factor 2 (RUNX2), type I collagen (COL1), BMP2, Wnt3a, Lrp6, and β-catenin mRNA expression, and prevented the increases of tibial sclerostin (SOST), RANK, RANKL, RANL/osteoprotegerin (OPG) gene levels in db/db mice. Our results show that WBV promoted bone quantity and quality in db/db mice with obvious

  12. Leishmania infantum Parasites Subvert the Host Inflammatory Response through the Adenosine A2A Receptor to Promote the Establishment of Infection

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    Mikhael H. F. Lima

    2017-07-01

    Full Text Available Adenosine is an endogenously released purine nucleoside that signals through four widely expressed G protein-coupled receptors: A1, A2A, A2B, and A3. Of these, A2AR is recognized as mediating major adenosine anti-inflammatory activity. During cutaneous leishmaniasis, adenosine induces immunosuppression, which promotes the establishment of infection. Herein, we demonstrated that A2AR signaling is exploited by Leishmania infantum parasites, the etiologic agent that causes Visceral Leishmaniasis, to successfully colonize the vertebrate host. A2AR gene-deleted mice exhibited a well-developed cellular reaction with a strong Th1 immune response in the parasitized organs. An intense infiltration of activated neutrophils into the disease-target organs was observed in A2AR−/− mice. These cells were characterized by high expression of CXCR2 and CD69 on their cell surfaces and increased cxcl1 expression. Interestingly, this phenotype was mediated by IFN-γ on the basis that a neutralizing antibody specific to this cytokine prevented neutrophilic influx into parasitized organs. In evaluating the immunosuppressive effects, we identified a decreased number of CD4+ FOXP3+ T cells and reduced il10 expression in A2AR−/− infected mice. During ex vivo cell culture, A2AR−/− splenocytes produced smaller amounts of IL-10. In conclusion, we demonstrated that the A2AR signaling pathway is detrimental to development of Th1-type adaptive immunity and that this pathway could be associated with the regulatory process. In particular, it promotes parasite surveillance.

  13. Gene delivery in malignant B cells using the combination of lentiviruses conjugated to anti-transferrin receptor antibodies and an immunoglobulin promoter.

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    Leoh, Lai Sum; Morizono, Kouki; Kershaw, Kathleen M; Chen, Irvin S Y; Penichet, Manuel L; Daniels-Wells, Tracy R

    2014-01-01

    We previously developed an antibody-avidin fusion protein (ch128.1Av) specific for the human transferrin receptor 1 (TfR1; CD71) to be used as a delivery vector for cancer therapy and showed that ch128.1Av delivers the biotinylated plant toxin saporin-6 into malignant B cells. However, as a result of widespread expression of TfR1, delivery of the toxin to normal cells is a concern. Therefore, we explored the potential of a dual targeted lentiviral-mediated gene therapy strategy to restrict gene expression to malignant B cells. Targeting occurs through the use of ch128.1Av or its parental antibody without avidin (ch128.1) and through transcriptional regulation using an immunoglobulin promoter. Flow cytometry was used to detect the expression of enhanced green fluorescent protein (EGFP) in a panel of cell lines. Cell viability after specific delivery of the therapeutic gene FCU1, a chimeric enzyme consisting of cytosine deaminase genetically fused to uracil phosphoribosyltransferse that converts the 5-fluorocytosine (5-FC) prodrug into toxic metabolites, was monitored using the MTS or WST-1 viability assay. We found that EGFP was specifically expressed in a panel of human malignant B-cell lines, but not in human malignant T-cell lines. EGFP expression was observed in all cell lines when a ubiquitous promoter was used. Furthermore, we show the decrease of cell viability in malignant plasma cells in the presence of 5-FC and the FCU1 gene. The present study demonstrates that gene expression can be restricted to malignant B cells and suggests that this dual targeted gene therapy strategy may help to circumvent the potential side effects of certain TfR1-targeted protein delivery approaches. Copyright © 2014 John Wiley & Sons, Ltd.

  14. Estrogen receptorpromoter methylation is a biomarker for outcome prediction of cisplatin resistance in triple-negative breast cancer.

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    Xu, Junnan; Sun, Tao; Guo, Xiangyu; Wang, Yan; Jing, Mingxi

    2018-03-01

    A number of previous studies have indicated the presence of a link between estrogen receptor-α (ERα) methylation and triple-negative breast cancer (TNBC). However, the association between ERα methylation and drug resistance during the treatment of TNBC remains unclear. Methylation-specific polymerase chain reaction was used to investigate the methylation of ERα in the genomic DNA of 35 patients with TNBC who were defined as cisplatin-based chemotherapy-resistant using chemosensitivity testing. Survival probabilities by covariates were assessed using Kaplan-Meier estimator survival analysis and Cox's proportional hazards models, adjusting for age, menopausal status, tumor size, lymph node metastasis and ERα promoter DNA methylation. Of the 35 patients with TNBC analyzed, 8 exhibited ERα promoter DNA methylation. Cisplatin resistance was confirmed to be overwhelmingly associated with ERα methylation by univariate and multivariate analysis. Even in a limited analysis in patients with ERα methylation, the results generated from methylated tumor tissue and unmethylated tumor tissue revealed that expression of breast cancer type 1/2 susceptibility proteins was increased in ERα-methylated breast tumor tissue compared with in unmethylated tissue. The ERα methylation group tended to have significantly shorter progression-free (P=0.010) and overall (P=0.023) survival times compared with those in the unmethylated group. Similarly, shorter progression-free (P=0.024) and overall (P=0.018) survival times were observed in the cisplatin-resistant group compared with the cisplatin-non-resistant group. ERα methylation predicts a poor clinical outcome for patients with TNBC. The results of the present study indicated that ERα methylation may be a candidate surrogate biomarker for outcome prediction and cisplatin resistance in TNBC. Further investigation is required to identify potential biomarkers in a larger cohort in a prospective study.

  15. G protein-coupled receptor 87 (GPR87 promotes the growth and metastasis of CD133⁺ cancer stem-like cells in hepatocellular carcinoma.

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    Mingxia Yan

    Full Text Available Hepatocellular carcinoma (HCC is a prevalent disease worldwide, and the majority of HCC-related deaths occur due to local invasion and distant metastasis. Cancer stem cells (CSCs are a small subpopulation of cancer cells that have been hypothesized to be responsible for metastatic disease. Recently, we and others have identified a CSC population from human HCC cell lines and xenograft tumors characterized by their expression of CD133. However, the precise molecular mechanisms by which CD133(+ cancer stem-like cells mediate HCC metastasis have not been sufficiently analyzed. Here, we have sorted HCC cells using CD133 as a cancer stem cell (CSC marker by magnetic-activated cell sorting (MACS and demonstrated that the CD133(+ HCC cells not only possess greater migratory and invasive capacity in vitro but are also endowed with enhanced metastatic capacity in vivo and in human HCC specimens when compared to CD133(- HCC cells. Gene expression analysis of the CD133(+ and CD133(- cells of the HCC line SMMC-7721 revealed that G protein-coupled receptor 87 (GPR87 is highly expressed in CD133(+ HCC cells. In this study, we explored the role of GPR87 in the regulation of CD133 expression. We demonstrated that the overexpression of GPR87 up-regulated CD133 expression, promoted CSC-associated migratory and invasive properties in vitro, and increased tumor initiation in vivo. Conversely, silencing of GPR87 expression reduced the levels of CD133 expression.GPR87 promotes the growth and metastasis of CD133(+ cancer stem-like cells, and our findings may reveal new targets for HCC prevention or therapy.

  16. Promoter region of the bovine growth hormone receptor gene: single nucleotide polymorphism discovery in cattle and association with performance in Brangus bulls.

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    Garrett, A J; Rincon, G; Medrano, J F; Elzo, M A; Silver, G A; Thomas, M G

    2008-12-01

    Expression of the GH receptor (GHR) gene and its binding with GH is essential for growth and fat metabolism. A GT microsatellite exists in the promoter of bovine GHR segregating short (11 bp) and long (16 to 20 bp) allele sequences. To detect SNP and complete an association study of genotype to phenotype, we resequenced a 1,195-bp fragment of DNA including the GT microsatellite and exon 1A. Resequencing was completed in 48 familialy unrelated Holstein, Jersey, Brown Swiss, Simmental, Angus, Brahman, and Brangus cattle. Nine SNP were identified. Phylogeny analyses revealed minor distance (i.e., Brahman cattle averaged 27.4 +/- 0.07% divergence from the Bos taurus breeds, whereas divergence of Brangus was intermediate. An association study of genotype to phenotype was completed with data from growing Brangus bulls (n = 553 from 96 sires) and data from 4 of the SNP flanking the GT microsatellite. These SNP were found to be in Hardy-Weinberg equilibrium and in phase based on linkage disequilibrium analyses (r(2) = 0.84 and D'= 0.92). An A/G tag SNP was identified (ss86273136) and was located in exon 1A, which began 88 bp downstream from the GT microsatellite. Minor allele frequency of the tag SNP was greater than 10%, and Mendelian segregation was verified in 3 generation pedigrees. The A allele was derived from Brahman, and the G allele was derived from Angus. This tag SNP genotype was a significant effect in analyses of rib fat data collected with ultrasound when bulls were ~365 d of age. Specifically, bulls of the GG genotype had 6.1% more (P = 0.0204) rib fat than bulls of the AA and AG genotypes, respectively. Tag SNP (ss86273136), located in the promoter of GHR, appears to be associated with a measure of corporal fat in Bos taurus x Bos indicus composite cattle.

  17. Toll like receptor-3 ligand poly-ICLC promotes the efficacy of peripheral vaccinations with tumor antigen-derived peptide epitopes in murine CNS tumor models

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    Eguchi Junichi

    2007-02-01

    Full Text Available Abstract Background Toll-like receptor (TLR3 ligands serve as natural inducers of pro-inflammatory cytokines capable of promoting Type-1 adaptive immunity, and TLR3 is abundantly expressed by cells within the central nervous system (CNS. To improve the efficacy of vaccine strategies directed against CNS tumors, we evaluated whether administration of a TLR3 ligand, polyinosinic-polycytidylic (poly-IC stabilized with poly-lysine and carboxymethylcellulose (poly-ICLC would enhance the anti-CNS tumor effectiveness of tumor peptide-based vaccinations. Methods C57BL/6 mice bearing syngeneic CNS GL261 glioma or M05 melanoma received subcutaneous (s.c. vaccinations with synthetic peptides encoding CTL epitopes- mEphA2 (671–679, hgp100 (25–33 and mTRP-2 (180–188 for GL261, or ovalbumin (OVA: 257–264 for M05. The mice also received intramuscular (i.m. injections with poly-ICLC. Results The combination of subcutaneous (s.c. peptide-based vaccination and i.m. poly-ICLC administration promoted systemic induction of antigen (Ag-specific Type-1 CTLs expressing very late activation antigen (VLA-4, which confers efficient CNS-tumor homing of vaccine-induced CTLs based on experiments with monoclonal antibody (mAb-mediated blockade of VLA-4. In addition, the combination treatment allowed expression of IFN-γ by CNS tumor-infiltrating CTLs, and improved the survival of tumor bearing mice in the absence of detectable autoimmunity. Conclusion These data suggest that poly-ICLC, which has been previously evaluated in clinical trials, can be effectively combined with tumor Ag-specific vaccine strategies, thereby providing a greater index of therapeutic efficacy.

  18. Oncogenic K-Ras Signals through Epidermal Growth Factor Receptor and Wild-Type H-Ras to Promote Radiation Survival in Pancreatic and Colorectal Carcinoma Cells

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    Keith A. Cengel

    2007-04-01

    Full Text Available Pancreatic and colorectal carcinomas frequently express oncogenic/mutant K-Ras that contributes to both tumorigenesis and clinically observed resistance to radiation treatment. We have previously shown that farnesyltransferase inhibitors (FTI radiosensitize many pancreatic and colorectal cancer cell lines that express oncogenic K-ras at doses that inhibit the prenylation and activation of H-Ras but not K-Ras. In the present study, we have examined the mechanism of FTI-mediated radiosensitization in cell lines that express oncogenic K-Ras and found that wild-type H-Ras is a contributor to radiation survival in tumor cells that express oncogenic K-Ras. In these experiments, inhibiting the expression of oncogenic K-Ras, wild-type H-Ras, or epidermal growth factor receptor (EGFR led to similar levels of radiosensitization as treatment with the FTI tipifarnib. Treatment with the EGFR inhibitor gefitinib led to similar levels of radiosensitization, and the combinations of tipifarnib or gefitinib plus inhibition of K-Ras, H-Ras, or EGFR expression did not provide additional radiosensitization compared with tipifarnib or gefitinib alone. Finally, supplementing culture medium with the EGFR ligand transforming growth factor o was able to reverse the radiosensitizing effect of inhibiting K-ras expression. Taken together, these findings suggest that EGFRactivated H-Ras signaling is initiated by oncogenic K-Ras to promote radiation survival in pancreatic and colorectal cancers.

  19. Receptor for advanced glycation end-products promotes premature senescence of proximal tubular epithelial cells via activation of endoplasmic reticulum stress-dependent p21 signaling.

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    Liu, Jun; Huang, Kun; Cai, Guang-Yan; Chen, Xiang-Mei; Yang, Ju-Rong; Lin, Li-Rong; Yang, Jie; Huo, Ben-Gang; Zhan, Jun; He, Ya-Ni

    2014-01-01

    Premature senescence is a key process in the progression of diabetic nephropathy (DN). In our study, we hypothesized that receptors for advanced glycation end-products (RAGE) mediate endoplasmic reticulum (ER) stress to induce premature senescence via p21 signaling activation in diabetic nephropathy. Here, we demonstrated that elevated expression of RAGE, ER stress marker glucose-regulated protein 78 (GRP78), and cell-cycle regulator p21 was all positively correlated with enhanced senescence-associated-β-galactosidase (SA-β-gal) activity in DN patients. In addition, the fraction of SA-β-gal or cells in the G0G1 phase were enhanced in cultured mouse proximal tubular epithelial cells (PTECs) and the expression of RAGE, GRP78 and p21 was up-regulated by advanced glycation end-products (AGEs) in a dose- and time-dependent manner. Interestingly, ER stress inducers or RAGE overexpression mimicked AGEs induced-premature senescence, and this was significantly suppressed by p21 gene silencing. However, RAGE blocking successfully attenuated AGEs-induced ER stress and p21 expression, as well as premature senescence. Moreover, ER stress inducers directly caused p21 activation, premature senescence, and also enhanced RAGE expression by positive feedback. These observations suggest that RAGE promotes premature senescence of PTECs by activation of ER stress-dependent p21 signaling. © 2013.

  20. Sex differences in cells expressing green fluorescent protein under the control of the estrogen receptorpromoter in the hypothalamus of mice.

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    Kyi-Tha-Thu, Chaw; Okoshi, Kota; Ito, Hiroto; Matsuda, Ken-Ichi; Kawata, Mitsuhiro; Tsukahara, Shinji

    2015-12-01

    Estradiol that originates from testicular testosterone and binds to estrogen receptor-α (ERα) during developing period acts to organize the male-type brain in mice. Here, we examined transgenic mice expressing green fluorescent protein (GFP) under the control of the ERα promoter, in which ERα-expressing cells in the brain can be visualized by GFP. Fluorescence microscopy revealed the existence of many GFP-expressing cells in the medial preoptic area, medial preoptic nucleus (MPN), bed nucleus of the stria terminalis (BNST), and striohypothalamic nucleus (StHy) of adult transgenic mice. Neuronal nuclear antigen, a neuron marker, but not glial fibrillary acidic protein, an astrocyte marker, was mostly expressed by GFP-expressing cells. Analysis of GFP expression area showed that adult females had higher GFP expression in a region including the ventral part of the BNST, StHy, and dorsal part of the MPN than in adult males. Such female-biased sex difference was also found in transgenic pups on postnatal day 5 and 8. The GFP expression area of adult females was decreased by postnatal treatment with testosterone or estradiol. These results indicate that GFP visualizes a sex difference of ERα-expressing neurons. The transgenic mice may be useful for the analysis of the sexual differentiation of the brain. Copyright © 2015 Elsevier Ireland Ltd and the Japan Neuroscience Society. All rights reserved.

  1. The Common Follicle-Stimulating Hormone Receptor (FSHR Promoter Polymorphism FSHR −29G > A Affects Androgen Production in Normal Human Small Antral Follicles

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    Tanni Borgbo

    2017-06-01

    Full Text Available Follicle-stimulating hormone receptors (FSHRs are almost exclusively expressed on granulosa cells, and FSH action is probably most clearly reflected in intrafollicular hormone milieu of antral follicles. Little is known about the possible effects of the common single nucleotide polymorphism (SNP FSHR −29G > A (rs1394205 on hormonal conditions in humsan small antral follicles (hSAFs obtained from women in the natural menstrual cycle. This study investigated the follicle fluid (FF concentrations of anti-Müllerian hormone, estradiol, progesterone, androstenedione, and testosterone in hSAF in relation to the different genotypes of FSHR −29G > A. FF from 362 follicles was collected in 95 women undergoing fertility preservation, who did not suffer from a disease that directly affected ovarian function. The testosterone levels of the minor A/A genotype were significantly increased compared to the A/G and the G/G genotype. Furthermore, significantly reduced androstenedione levels were observed for the G/G genotype, as compared to the A/G genotype, while the other hormones did not show statistical significant differences. In conclusion, the androgen levels of hSAF were significantly elevated in the minor SNP genotype in the FSHR promoter polymorphism FSHR −29G > A.

  2. Histone Deacetylase Inhibitors Restore Cell Surface Expression of the Coxsackie Adenovirus Receptor and Enhance CMV Promoter Activity in Castration-Resistant Prostate Cancer Cells

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    Laura Kasman

    2012-01-01

    Full Text Available Adenoviral gene therapy using the death receptor ligand TRAIL as the therapeutic transgene can be safely administered via intraprostatic injection but has not been evaluated for efficacy in patients. Here we investigated the efficacy of adenoviral TRAIL gene therapy in a model of castration resistant prostate cancer and found that intratumoral injections can significantly delay tumor growth but cannot eliminate established lesions. We hypothesized that an underlying cause is inefficient adenoviral delivery. Using the LNCaP progression model of prostate cancer we show that surface CAR expression decreases with increasing tumorigenicity and that castration resistant C4-2b cells were more difficult to transduce with adenovirus than castration sensitive LNCaP cells. Many genes, including CAR, are epigenetically silenced during transformation but a new class of chemotherapeutic agents, known as histone deacetylase inhibitors (HDACi, can reverse this process. We demonstrate that HDACi restore CAR expression and infectivity in C4-2b cells and enhance caspase activation in response to infection with a TRAIL adenovirus. We also show that in cells with high surface CAR expression, HDACi further enhance transgene expression from the CMV promoter. Thus HDACi have multiple beneficial effects, which may enhance not only viral but also non-viral gene therapy of castration resistant prostate cancer.

  3. CDO1 promoter methylation is a biomarker for outcome prediction of anthracycline treated, estrogen receptor-positive, lymph node-positive breast cancer patients.

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    Dietrich, Dimo; Krispin, Manuel; Dietrich, Jörn; Fassbender, Anne; Lewin, Jörn; Harbeck, Nadia; Schmitt, Manfred; Eppenberger-Castori, Serenella; Vuaroqueaux, Vincent; Spyratos, Frédérique; Foekens, John A; Lesche, Ralf; Martens, John W M

    2010-06-01

    Various biomarkers for prediction of distant metastasis in lymph-node negative breast cancer have been described; however, predictive biomarkers for patients with lymph-node positive (LNP) disease in the context of distinct systemic therapies are still very much needed. DNA methylation is aberrant in breast cancer and is likely to play a major role in disease progression. In this study, the DNA methylation status of 202 candidate loci was screened to identify those loci that may predict outcome in LNP/estrogen receptor-positive (ER+) breast cancer patients with adjuvant anthracycline-based chemotherapy. Quantitative bisulfite sequencing was used to analyze DNA methylation biomarker candidates in a retrospective cohort of 162 LNP/ER+ breast cancer patients, who received adjuvant anthracycline-based chemotherapy. First, twelve breast cancer specimens were analyzed for all 202 candidate loci to exclude genes that showed no differential methylation. To identify genes that predict distant metastasis, the remaining loci were analyzed in 84 selected cases, including the 12 initial ones. Significant loci were analyzed in the remaining 78 independent cases. Metastasis-free survival analysis was conducted by using Cox regression, time-dependent ROC analysis, and the Kaplan-Meier method. Pairwise multivariate regression analysis was performed by linear Cox Proportional Hazard models, testing the association between methylation scores and clinical parameters with respect to metastasis-free survival. Of the 202 loci analysed, 37 showed some indication of differential DNA methylation among the initial 12 patient samples tested. Of those, 6 loci were associated with outcome in the initial cohort (n = 84, log rank test, p Promoter DNA methylation of cysteine dioxygenase 1 (CDO1) was confirmed in univariate and in pairwise multivariate analysis adjusting for age at surgery, pathological T stage, progesterone receptor status, grade, and endocrine therapy as a strong and independent

  4. Interleukin 6 Present in Inflammatory Ascites from Advanced Epithelial Ovarian Cancer Patients Promotes Tumor Necrosis Factor Receptor 2-Expressing Regulatory T Cells

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    Nirmala Chandralega Kampan

    2017-11-01

    Full Text Available BackgroundEpithelial ovarian cancer (EOC remains a highly lethal gynecological malignancy. Ascites, an accumulation of peritoneal fluid present in one-third of patients at presentation, is linked to poor prognosis. High levels of regulatory T cells (Tregs in ascites are correlated with tumor progression and reduced survival. Malignant ascites harbors high levels of Tregs expressing the tumor necrosis factor receptor 2 (TNFR2, as well as pro-inflammatory factors such as interleukin 6 (IL-6 and tumor necrosis factor (TNF. IL-6 is also associated with poor prognosis. Herein, we study the effect of IL-6 and TNF present in ascites on the modulation of TNFR2 expression on T cells, and specifically Tregs.MethodsAscites and respective peripheral blood sera were collected from 18 patients with advanced EOC and soluble biomarkers, including IL-6, sTNFR2, IL-10, TGF-β, and TNF, were quantified using multiplexed bead-based immunoassay. Peripheral blood mononuclear cells (PBMC from healthy donors were incubated with cell-free ascites for 48 h (or media as a negative control. In some experiments, IL-6 or TNF within the ascites were neutralized by using monoclonal antibodies. The phenotype of TNFR2+ Tregs and TNFR2− Tregs were characterized post incubation in ascites. In some experiments, cell sorted Tregs were utilized instead of PBMC.ResultsHigh levels of immunosuppressive (sTNFR2, IL-10, and TGF-β and pro-inflammatory cytokines (IL-6 and TNF were present in malignant ascites. TNFR2 expression on all T cell subsets was higher in post culture in ascites and highest on CD4+CD25hiFoxP3+ Tregs, resulting in an increased TNFR2+ Treg/effector T cell ratio. Furthermore, TNFR2+ Tregs conditioned in ascites expressed higher levels of the functional immunosuppressive molecules programmed cell death ligand-1, CTLA-4, and GARP. Functionally, TNFR2+ Treg frequency was inversely correlated with interferon-gamma (IFN-γ production by effector T cells, and was

  5. Interleukin 6 Present in Inflammatory Ascites from Advanced Epithelial Ovarian Cancer Patients Promotes Tumor Necrosis Factor Receptor 2-Expressing Regulatory T Cells.

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    Kampan, Nirmala Chandralega; Madondo, Mutsa Tatenda; McNally, Orla M; Stephens, Andrew N; Quinn, Michael A; Plebanski, Magdalena

    2017-01-01

    Epithelial ovarian cancer (EOC) remains a highly lethal gynecological malignancy. Ascites, an accumulation of peritoneal fluid present in one-third of patients at presentation, is linked to poor prognosis. High levels of regulatory T cells (Tregs) in ascites are correlated with tumor progression and reduced survival. Malignant ascites harbors high levels of Tregs expressing the tumor necrosis factor receptor 2 (TNFR2), as well as pro-inflammatory factors such as interleukin 6 (IL-6) and tumor necrosis factor (TNF). IL-6 is also associated with poor prognosis. Herein, we study the effect of IL-6 and TNF present in ascites on the modulation of TNFR2 expression on T cells, and specifically Tregs. Ascites and respective peripheral blood sera were collected from 18 patients with advanced EOC and soluble biomarkers, including IL-6, sTNFR2, IL-10, TGF-β, and TNF, were quantified using multiplexed bead-based immunoassay. Peripheral blood mononuclear cells (PBMC) from healthy donors were incubated with cell-free ascites for 48 h (or media as a negative control). In some experiments, IL-6 or TNF within the ascites were neutralized by using monoclonal antibodies. The phenotype of TNFR2 + Tregs and TNFR2 - Tregs were characterized post incubation in ascites. In some experiments, cell sorted Tregs were utilized instead of PBMC. High levels of immunosuppressive (sTNFR2, IL-10, and TGF-β) and pro-inflammatory cytokines (IL-6 and TNF) were present in malignant ascites. TNFR2 expression on all T cell subsets was higher in post culture in ascites and highest on CD4 + CD25 hi FoxP3 + Tregs, resulting in an increased TNFR2 + Treg/effector T cell ratio. Furthermore, TNFR2 + Tregs conditioned in ascites expressed higher levels of the functional immunosuppressive molecules programmed cell death ligand-1, CTLA-4, and GARP. Functionally, TNFR2 + Treg frequency was inversely correlated with interferon-gamma (IFN-γ) production by effector T cells, and was uniquely able to suppress TNFR2

  6. The wake-promoting drug Modafinil prevents motor impairment in sickness behavior induced by LPS in mice: Role for dopaminergic D1 receptor.

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    Zager, Adriano; Brandão, Wesley Nogueira; Margatho, Rafael Oliveira; Peron, Jean Pierre; Tufik, Sergio; Andersen, Monica Levy; Kornum, Birgitte Rahbek; Palermo-Neto, João

    2018-02-02

    The wake-promoting drug Modafinil has been used for many years for treatment of Narcolepsy and Excessive Daytime Sleepiness, due to a dopamine-related psychostimulant action. Recent studies have indicated that Modafinil prevents neuroinflammation in animal models. Thus, the aim of the present study was to evaluate the effect of Modafinil pretreatment in the Lipopolysaccharide (LPS)-induced sickness and depressive-like behaviors. Adult male C57BL/6J mice were pretreated with Vehicle or Modafinil (90mg/Kg) and, 30min later, received a single saline or LPS (2mg/Kg) administration, and were submitted to the open field and elevated plus maze test 2h later. After 24h, mice were subjected to tail suspension test, followed by either flow cytometry with whole brain for CD11b + CD45 + cells or qPCR in brain areas for cytokine gene expression. Modafinil treatment prevented the LPS-induced motor impairment, anxiety-like and depressive-like behaviors, as well as the increase in brain CD11b + CD45 high cells induced by LPS. Our results indicate that Modafinil pretreatment also decreased the IL-1β gene upregulation caused by LPS in brain areas, which is possibly correlated with the preventive behavioral effects. The pharmacological blockage of the dopaminergic D1R by the drug SCH-23390 counteracted the effect of Modafinil on locomotion and anxiety-like behavior, but not on depressive-like behavior and brain immune cells. The dopaminergic D1 receptor signaling is essential to the Modafinil effects on LPS-induced alterations in locomotion and anxiety, but not on depression and brain macrophages. This evidence suggests that Modafinil treatment might be useful to prevent inflammation-related behavioral alterations, possibly due to a neuroimmune mechanism. Copyright © 2017 Elsevier Inc. All rights reserved.

  7. Does the simultaneous tumor necrosis factor receptor 2, tumor necrosis factor promoter gene polymorphism represent a higher risk for alcoholic liver disease?

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    Machado, Mariana Verdelho; Martins, Alexandra; Almeida, Rosário; Marques-Vidal, Pedro; Gonçalves, Maria S; Camilo, Maria E; Cortez-Pinto, Helena

    2009-02-01

    Tumor necrosis factor alpha (TNF-alpha) is a proinflammatory cytokine that seems to play a crucial role in the pathogenesis of alcoholic liver disease (ALD). TNF-alpha exerts its effects by binding to specific receptors (TNFR); the polymorphism of TNFRII T587G has been associated with increased TNF apoptotic response and its presence may increase the risk to develop liver disease. The aim of this study was to evaluate the prevalence of the TNF-alpha G238A promoter and TNFRII polymorphisms, individually or simultaneously, in ALD. TNF-alpha G238A and TNFRII T587G polymorphisms were studied in 103 unrelated patients with ALD (biopsy confirmed or clinical evidence) and in 76 heavy drinkers without liver disease (NLD). Single nucleotide polymorphism gene was detected by a polymerase chain reaction-restriction fragment length polymorphisms method. All patients had, at least, a 5 year history of alcohol consumption greater than 80 g/day. TNF-alpha G238A allele frequency was similar in both groups. TNFRII T587G allele frequency was slightly higher in the ALD group than in the NLD group (21 vs. 18%, P=NS). TNF-alpha G238A and TNFRII T587G were simultaneously present in six ALD patients and in none of NLD patients (P=0.04). Although individually there was no association between TNFRII T587G or TNF-alpha G238A polymorphisms and ALD, this study suggests that the presence of both polymorphisms may enhance the susceptibility for ALD. TNF-alpha G238A may increase TNF-alpha production, which when associated with TNFRII T587G, can further exacerbate TNF-alpha response leading to a greater risk of ALD.

  8. TRV0109101, a G Protein-Biased Agonist of the µ-Opioid Receptor, Does Not Promote Opioid-Induced Mechanical Allodynia following Chronic Administration.

    Science.gov (United States)

    Koblish, Michael; Carr, Richard; Siuda, Edward R; Rominger, David H; Gowen-MacDonald, William; Cowan, Conrad L; Crombie, Aimee L; Violin, Jonathan D; Lark, Michael W

    2017-08-01

    Prescription opioids are a mainstay in the treatment of acute moderate to severe pain. However, chronic use leads to a host of adverse consequences including tolerance and opioid-induced hyperalgesia (OIH), leading to more complex treatment regimens and diminished patient compliance. Patients with OIH paradoxically experience exaggerated nociceptive responses instead of pain reduction after chronic opioid usage. The development of OIH and tolerance tend to occur simultaneously and, thus, present a challenge when studying the molecular mechanisms driving each phenomenon. We tested the hypothesis that a G protein-biased µ -opioid peptide receptor (MOPR) agonist would not induce symptoms of OIH, such as mechanical allodynia, following chronic administration. We observed that the development of opioid-induced mechanical allodynia (OIMA), a model of OIH, was absent in β -arrestin1 -/- and β -arrestin2 -/- mice in response to chronic administration of conventional opioids such as morphine, oxycodone and fentanyl, whereas tolerance developed independent of OIMA. In agreement with the β -arrestin knockout mouse studies, chronic administration of TRV0109101, a G protein-biased MOPR ligand and structural analog of oliceridine, did not promote the development of OIMA but did result in drug tolerance. Interestingly, following induction of OIMA by morphine or fentanyl, TRV0109101 was able to rapidly reverse allodynia. These observations establish a role for β -arrestins in the development of OIH, independent of tolerance, and suggest that the use of G protein-biased MOPR ligands, such as oliceridine and TRV0109101, may be an effective therapeutic avenue for managing chronic pain with reduced propensity for opioid-induced hyperalgesia. Copyright © 2017 by The American Society for Pharmacology and Experimental Therapeutics.

  9. Activation of AMPA receptor promotes TNF-α release via the ROS-cSrc-NFκB signaling cascade in RAW264.7 macrophages

    Energy Technology Data Exchange (ETDEWEB)

    Cheng, Xiu-Li [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Ding, Fan [Office of Scientific R& D, Tsinghua University, Beijing (China); Li, Hui; Tan, Xiao-Qiu [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Liu, Xiao [Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Cao, Ji-Min, E-mail: caojimin@126.com [Department of Physiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China); Gao, Xue, E-mail: longlongnose@163.com [Department of Pathophysiology, Institute of Basic Medical Sciences, Chinese Academy of Medical Sciences, School of Basic Medicine, Peking Union Medical College, Beijing (China)

    2015-05-29

    The relationship between glutamate signaling and inflammation has not been well defined. This study aimed to investigate the role of AMPA receptor (AMPAR) in the expression and release of tumor necrosis factor-alpha (TNF-α) from macrophages and the underlying mechanisms. A series of approaches, including confocal microscopy, immunofluorescency, flow cytometry, ELISA and Western blotting, were used to estimate the expression of AMPAR and downstream signaling molecules, TNF-α release and reactive oxygen species (ROS) generation in the macrophage-like RAW264.7 cells. The results demonstrated that AMPAR was expressed in RAW264.7 cells. AMPA significantly enhanced TNF-α release from RAW264.7 cells, and this effect was abolished by CNQX (AMPAR antagonist). AMPA also induced elevation of ROS production, phosphorylation of c-Src and activation of nuclear factor (NF)-κB in RAW264.7 cells. Blocking c-Src by PP2, scavenging ROS by glutathione (GSH) or inhibiting NF-κB activation by pyrrolidine dithiocarbamate (PDTC) decreased TNF-α production from RAW264.7 cells. We concluded that AMPA promotes TNF-α release in RAW264.7 macrophages likely through the following signaling cascade: AMPAR activation → ROS generation → c-Src phosphorylation → NF-κB activation → TNF-α elevation. The study suggests that AMPAR may participate in macrophage activation and inflammation. - Highlights: • AMPAR is expressed in RAW264.7 macrophages and is upregulated by AMPA stimulation. • Activation of AMPAR stimulates TNF-α release in macrophages through the ROS-cSrc-NFκB signaling cascade. • Macrophage AMPAR signaling may play an important role in inflammation.

  10. Human papillomavirus type 16 E6 oncoprotein promotes proliferation and invasion of non-small cell lung cancer cells through Toll-like receptor 3 signaling pathway.

    Science.gov (United States)

    Wang, Xia; Zhang, Zhiqiang; Cao, Huimin; Niu, Wenyi; Li, Mingying; Xi, Xiu'e; Wang, Jing

    2017-10-01

    Human papillomavirus (HPV) oncoproteins play vital roles in non-small cell lung cancer (NSCLC) pathogenesis, and Toll-like receptors (TLRs) contribute to tumor progression. However, interaction between HPV oncoproteins and TLR signaling in NSCLC progression remains unclear. Thus, the aim of the study was to explore effects of HPV16 E6 oncoprotein-induced TLRs pathway on growth and invasion of NSCLC cells and to examine potential mechanisms being involved. Recombinant plasmid (pcDNA-HPV16 E6) expressing HPV16 E6 protein was constructed. The expression prolife of TLRs was measured in NSCLC cell line A549 with or without pcDNA-HPV16 E6 transfection by real-time reverse polymerase chain reaction and Western blot. Cellular proliferation, invasion, cytokine productions, and downstream signaling pathways were also examined in TLR3-silencing/pcDNA-HPV16 E6 transfect A549 cells. Overexpression of HPV16 E6 increased proliferation, invasion, proliferation cytokine secretion, and TLR3 expression of A549 cells, while TLR3 silence inhibited HPV16 E6-induced tumor bioactivities of A549 cells. Down-regulation of TLR3 suppressed HPV16 E6-induced phosphorylation of Src, but did not affect TRIF expression. Moreover, inhibition of Src pathway also suppressed proliferation and invasion of A549 cells. In conclusion, HPV16 E6 oncoprotein promoted the bioactivities of NSCLC cells. TLR3-Src signaling pathway might be involved in this procession by up-regulation of cytokine production. The interaction between HPV16 E6 protein and TLR3 might contribute to the poor prognosis of NSCLC. © 2017 Wiley Periodicals, Inc.

  11. Deficiency of Protein Tyrosine Phosphatase Non-Receptor Type 2 in Intestinal Epithelial Cells Has No Appreciable Impact on Dextran Sulphate Sodium Colitis Severity But Promotes Wound Healing.

    Science.gov (United States)

    Kasper, Stephanie H; Spalinger, Marianne R; Leonardi, Irina; Gerstgrasser, Alexandra; Raselli, Tina; Gottier, Claudia; Atrott, Kirstin; Frey-Wagner, Isabelle; Fischbeck-Terhalle, Anne; Rogler, Gerhard; Scharl, Michael

    2016-01-01

    The protein tyrosine phosphatase non-receptor type 2 (PTPN2) is known to mediate susceptibility to inflammatory bowel diseases. Cell culture experiments suggest that PTPN2 influences barrier function, autophagy and secretion of pro-inflammatory cytokines. PTPN2 knockout mice die a few weeks after birth due to systemic inflammation, emphasizing the importance of this phosphatase in inflammatory processes. The aim of this study was to investigate the role of PTPN2 in colon epithelial cells by performing dextran sulphate sodium (DSS)-induced colitis in PTPN2xVilCre mice. Acute colitis was induced by administering 2.5 or 2% DSS for 7 days and chronic colitis by 4 cycles of treatment using 1% DSS. Body weight of mice was measured regularly and colonoscopy was done at the end of the experiments. Mice were sacrificed afterwards and colon specimens were obtained for H&E staining. For analysis of wound healing, mechanical wounds were introduced during endoscopy and wound closure assessed by daily colonoscopy. Although colonoscopy and weight development suggested changes in colitis severity, the lack of any influence of PTPN2 deficiency on histological scoring for inflammation severity after acute or chronic DSS colitis indicates that colitis severity is not influenced by epithelial-specific loss of PTPN2. Chronic colitis induced the development of aberrant crypt foci more frequently in PTPN2xVilCre mice compared to their wild type littermates. On the other hand, loss of PTPN2-induced enhanced epithelial cell proliferation and promoted wound closure. Loss of PTPN2 in intestinal epithelial cells (IECs) has no significant influence on inflammation in DSS colitis. Obviously, loss of PTPN2 in IECs can be compensated in vivo, thereby suppressing a phenotype. This lack of a colitis-phenotype might be due to enhanced epithelial cell proliferation and subsequent increased wound-healing capacity of the epithelial layer. © 2016 S. Karger AG, Basel.

  12. Clonorchis sinensis excretory/secretory products promote the secretion of TNF-alpha in the mouse intrahepatic biliary epithelial cells via Toll-like receptor 4.

    Science.gov (United States)

    Yan, Chao; Wang, Yan-Hong; Yu, Qian; Cheng, Xiao-Dan; Zhang, Bei-Bei; Li, Bo; Zhang, Bo; Tang, Ren-Xian; Zheng, Kui-Yang

    2015-10-24

    Toll-like receptor 4 (TLR4), as one of the most important pathogen pattern recognitions (PPRs) plays a central role in elicitation of innate immunity and mediation of adaptive responses against foreign antigens. However, little is known of the roles of TLR4 in the immune responses of biliary epithelial cells (BECs) induced by Clonorchis sinensis, a parasite of significance in human health. In the present study, the primary mouse intrahepatic biliary epithelial cells (MIBECs) were pre-treated with TLR4 inhibitor peptide or control peptide and then stimulated by excretory/secretory products (ESP) of C. sinensis, respectively. The expressions of TLR4 and relative cytokines were determined using western blot and a bead-based analytic detection system, respectively. The results showed that ESP of C. sinensis significantly increased the expression of TLR4 which promoted the expression of MyD88 and NF-κB in BECs; the levels of TNF-α but not IL-6 from MIBECs stimulated by ESP alone were also considerably increased, compared with the group of the medium stimulated. However, the concentration of TNF-α was significantly decreased when MIBECs were pre-treated with TLR4 inhibitor. In addition, ESP could depress the level of IL-6 in MIBECs which was elevated by LPS. Our data for the first time demonstrate that ESP of C. sinensis can potently induce secretion of pro-inflammatory cytokines via TLR4 in MIBECs, which suggests that TLR4 plays an important role in host defenses against C. sinensis and the pathogenesis of clonorchiasis.

  13. Serotonin 2A receptor (5-HT2A) gene promoter variant interacts with chronic perceived stress to modulate resting parasympathetic activity in humans.

    Science.gov (United States)

    Chang, Chuan-Chia; Fang, Wen-Hui; Chang, Hsin-An; Chang, Tieh-Ching; Shyu, Jia-Fwa; Huang, San-Yuan

    2017-02-01

    Decreased resting vagal (parasympathetic) tone is implicated in the development of stress-related disorders, including anxiety and depression. Chronic stress elevates the expression of serotonin 2A receptors (5-HT2A), while activation of 5-HT2A leads to inhibition of parasympathetic synaptic transmission. The T allele of the promoter variant, rs6311 (C>T), of the 5-HT2A gene has been shown to increase the 5-HT2A expression in vitro and to be associated with anxiety and depressive disorders. We thus hypothesized that the 5-HT2A functional polymorphism may influence resting vagal activity among persons with chronically high levels of perceived stress. A total of 1138 well-defined healthy, medication-free Han Chinese were included for 5-HT2A genotyping. The Perceived Stress Scale (PSS) was used to measure the level of perceived stress during the last month and participants were divided into low and high PSS groups. Resting-state heart rate variability (HRV) was used to assess autonomic function. No significant between-genotype difference was found in any HRV variable in the low PSS group (n=610). However, in the high PSS group (n=528), high frequency power and root mean square of successive heartbeat interval differences (both HRV indices of parasympathetic activity) were significantly reduced in T/T genotype carriers compared to C/C homozygotes. Our findings are the first to show that individuals homozygous for the high-expressing 5-HT2A (T) allele exhibit diminished resting vagal tone-an index of stress vulnerability-when experiencing chronically elevated levels of perceived stress. The present results may advance our understanding of the genetic mechanism underlying individual differences in susceptibility to stress. Copyright © 2016 Elsevier Ltd. All rights reserved.

  14. Sirtuin1 promotes osteogenic differentiation through downregulation of peroxisome proliferator-activated receptor γ in MC3T3-E1 cells

    Energy Technology Data Exchange (ETDEWEB)

    Qu, Bo [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China); Ma, Yuan [Department of Neurosurgery, Chengdu Military General Hospital, Chengdu 610083 (China); Yan, Ming [Department of Orthopaedics, Xijing Hospital of The Fourth Military Medical University, Xi’an 710032 (China); Gong, Kai; Liang, Feng; Deng, Shaolin; Jiang, Kai; Ma, Zehui [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China); Pan, Xianming, E-mail: xianmingpanxj@163.com [Department of Orthopaedics, Chengdu Military General Hospital, Chengdu 610083 (China)

    2016-09-09

    Osteoporosis is a skeletal disorder characterized by bone loss, resulting in architectural deterioration of the skeleton, decreased bone strength and an increased risk of fragility fractures. Strengthening osteogenesis is an effective way to relieve osteoporosis. Sirtuin1 (Sirt1) is a nicotinamide adenine dinucleotide (NAD{sup +})-dependent deacetylase, which is reported to be involved in improving osteogenesis. Sirt1 targets peroxisome proliferator-activated receptor γ (PPARγ) in the regulation of adipose tissues; however, the molecular mechanism of Sirt1 in osteogenic differentiation is still unknown. PPARγ tends to induce more adipogenic differentiation rather than osteogenic differentiation. Hence, we hypothesized that Sirt1 facilitates osteogenic differentiation through downregulation of PPARγ signaling. Mouse pre-osteoblastic MC3T3-E1 cells were cultured under osteogenic medium. Sirt1 was overexpressed through plasmid transfection. The results showed that high expression of Sirt1 was associated with increased osteogenic differentiation, as indicated by quantitative PCR and Western blot analysis of osteogenic markers, and Von Kossa staining. Sirt1 overexpression also directly and negatively regulated the expression of PPARγ and its downstream molecules. Use of the PPARγ agonist Rosiglitazone, reversed the effects of Sirt1 on osteogenic differentiation. Using constructed luciferase plasmids, we demonstrated a role of Sirt1 in inhibiting PPARγ–induced activity and expression of adipocyte–specific genes, including acetyl-coenzyme A carboxylase (Acc) and fatty acid binding protein 4 (Fabp4). The interaction between Sirt1 and PPARγ was further confirmed using co-immunoprecipitation analysis. Together, these results reveal a novel mechanism for Sirt1 in osteogenic differentiation through downregulation of PPARγ activity. These findings suggest that the Sirt1–PPARγ pathway may represent a potential target for enhancement of osteogenesis and treatment

  15. Lipopolysaccharide-induced toll-like receptor 4 signaling in esophageal squamous cell carcinoma promotes tumor proliferation and regulates inflammatory cytokines expression.

    Science.gov (United States)

    Zu, Yukun; Ping, Wei; Deng, Taoran; Zhang, Ni; Fu, Xiangning; Sun, Wei

    2017-02-01

    Emerging evidence suggests toll-like receptor 4 (TLR4) signaling contributes to cancer development and progression. However, the consequences of signaling via the TLR4 pathway in esophageal squamous cell carcinoma (ESCC) are still unclear. Here, we investigated the impact of Lipopolysaccharide (LPS)-induced TLR4 signaling on ESCC cell proliferation, inflammatory cytokines expression, and downstream molecular mechanisms. Seventy-eight ESCC and 26 normal esophageal specimens were analyzed by immunohistochemistry, and two cell lines (Eca-109 and TE-1) were used for in vitro studies. LPS, a natural agonist of TLR4, was used to activate TLR4 signaling. The effects of LPS-TLR4 signaling on cell proliferation and inflammatory cytokines regulation were examined. Specific inhibitors of mitogen-activated protein kinase (MAPK) (extracellular regulated protein kinase [ERK] and p38) signaling pathways were used to investigate the role of each pathway in LPS-TLR4 signaling. TLR4 protein was increased in ESCC tumor tissues compared with the adjacent normal tissues. TLR4 over-expression was significantly correlated with tumor differentiation grade, lymph node metastasis, and UICC stage. LPS-induced activation of TLR4 signaling promoted cancer cell proliferation, increased production of proinflammatory or immunosuppressive cytokines TNF-α, TGF-β and inhibited the anti-inflammatory cytokine IL-10. LPS-TLR4 signaling was associated with the activation of ERK and p38 MAPK signaling pathways. Further inactivation of the two pathways by specific inhibitors attenuated cell proliferation and inflammatory cytokines expression induced by LPS. Our results indicate that LPS-TLR4 signaling in cancer cells contributes to the progression of human ESCC. © 2016 International Society for Diseases of the Esophagus.

  16. Loss of aryl hydrocarbon receptor promotes gene changes associated with premature hematopoietic stem cell exhaustion and development of a myeloproliferative disorder in aging mice.

    Science.gov (United States)

    Singh, Kameshwar P; Bennett, John A; Casado, Fanny L; Walrath, Jason L; Welle, Stephen L; Gasiewicz, Thomas A

    2014-01-15

    Loss of immune function and increased hematopoietic disease are among the most clinically significant consequences of aging. Hematopoietic stem cells (HSCs) from mice lacking aryl hydrocarbon receptor (AhR) have high rates of cell division. Studies were designed to test the hypothesis that aging AhR-null allele (AhR-KO) mice develop premature HSC exhaustion, and changes leading to hematological disease. Compared to wild-type, aging AhR-KO mice showed a decreased survival rate, splenomegaly, increased circulating white blood cells, hematopoietic cell accumulation in tissues, and anemia. Analysis of bone marrow indicated increased numbers of stem/progenitor and lineage-committed cells, but decreased erythroid progenitors. There was also decreased self-renewal capacity of HSCs determined by competitive repopulation and serial transplantation. HSCs also showed increased levels of reactive oxygen species (ROS), Ki-67, and γ-H2A.X, but decreased p16(Ink4a). Splenic cells from aging KO mice had abnormal expression of genes, including Gata-1, Sh2d3c, Gfi-1, p21, and c-myc, involved in trafficking and associated with leukemia. HSCs from AhR-KO mice had gene changes related to HSC maintenance and consistent with phenotype observed. The most prominent gene changes (overexpression of Srpk2, Creb1, Hes1, mtor, pdp1) have been associated with HSC hyperproliferation, leukemia, and accelerated aging. Pathway analyses also indicated an enrichment of genes associated with oxidative stress, acute myelogenous leukemia, aging, and heat shock response, and the β-catenin/Wnt pathways. These data indicate that loss of AhR and associated changes in multiple signaling pathways promote premature HSC exhaustion and development of a myeloproliferative disorder. They also implicate a critical role of the AhR in the regulation of HSCs.

  17. Membrane progesterone receptor beta (mPR?/Paqr8) promotes progesterone-dependent neurite outgrowth in PC12 neuronal cells via non-G protein-coupled receptor (GPCR) signaling

    OpenAIRE

    Kasubuchi, Mayu; Watanabe, Keita; Hirano, Kanako; Inoue, Daisuke; Li, Xuan; Terasawa, Kazuya; Konishi, Morichika; Itoh, Nobuyuki; Kimura, Ikuo

    2017-01-01

    Recently, sex steroid membrane receptors garnered world-wide attention because they may be related to sex hormone-mediated unknown rapid non-genomic action that cannot be currently explained by their genomic action via nuclear receptors. Progesterone affects cell proliferation and survival via non-genomic effects. In this process, membrane progesterone receptors (mPRα, mPRβ, mPRγ, mPRδ, and mPRε) were identified as putative G protein-coupled receptors (GPCRs) for progesterone. However, the st...

  18. Hypomethylation of miR-142 promoter and upregulation of microRNAs that target the oxytocin receptor gene in the autism prefrontal cortex.

    Science.gov (United States)

    Mor, Michal; Nardone, Stefano; Sams, Dev Sharan; Elliott, Evan

    2015-01-01

    MicroRNAs are small RNA molecules that regulate the translation of protein from gene transcripts and are a powerful mechanism to regulate gene networks. Next-generation sequencing technologies have produced important insights into gene transcription changes that occur in the brain of individuals diagnosed with autism spectrum disorder (asd). However, these technologies have not yet been employed to uncover changes in microRNAs in the brain of individuals diagnosed with asd. Small RNA next-generation sequencing was performed on RNA extracted from 12 human autism brain samples and 12 controls. Real-time PCR was used to validate a sample of the differentially expressed microRNAs, and bioinformatic analysis determined common pathways of gene targets. MicroRNA expression data was correlated to genome-wide DNA methylation data to determine if there is epigenetic regulation of dysregulated microRNAs in the autism brain. Luciferase assays, real-time PCR, and Western blot analysis were used to determine how dysregulated microRNAs may regulate the expression and translation of an autism-related gene transcript. We determined that miR-142-5p, miR-142-3p, miR-451a, miR-144-3p, and miR-21-5p are overexpressed in the asd brain. Furthermore, the promoter region of the miR-142 gene is hypomethylated in the same brain samples, suggesting that epigenetics plays a role in dysregulation of microRNAs in the brain. Bioinformatic analysis revealed that these microRNAs target genes that are involved in synaptic function. Further bioinformatic analysis, coupled with in vitro luciferase assays, determined that miR-451a and miR-21-5p can target the oxytocin receptor (OXTR) gene. OXTR gene expression is increased in these same brain samples, and there is a positive correlation between miR-21-5p and OXTR expression. However, miR-21-5p expression negatively correlates to production of OXTR protein from the OXTR transcript. Therefore, we suggest that miR-21-5p may attenuate OXTR expression in

  19. Fibroblast growth factor receptor 1 activation in mammary tumor cells promotes macrophage recruitment in a CX3CL1-dependent manner.

    Directory of Open Access Journals (Sweden)

    Johanna R Reed

    Full Text Available Tumor formation is an extensive process requiring complex interactions that involve both tumor cell-intrinsic pathways and soluble mediators within the microenvironment. Tumor cells exploit the intrinsic functions of many soluble molecules, including chemokines and their receptors, to regulate pro-tumorigenic phenotypes that are required for growth and progression of the primary tumor. Previous studies have shown that activation of inducible FGFR1 (iFGFR1 in mammary epithelial cells resulted in increased proliferation, migration, and invasion in vitro and tumor formation in vivo. These studies also demonstrated that iFGFR1 activation stimulated recruitment of macrophages to the epithelium where macrophages contributed to iFGFR1-mediated epithelial cell proliferation and angiogenesis. The studies presented here further utilize this model to identify the mechanisms that regulate FGFR1-induced macrophage recruitment. Results from this study elucidate a novel role for the inflammatory chemokine CX3CL1 in FGFR1-induced macrophage migration. Specifically, we illustrate that activation of both the inducible FGFR1 construct in mouse mammary epithelial cells and endogenous FGFR in the triple negative breast cancer cell line, HS578T, leads to expression of the chemokine CX3CL1. Furthermore, we demonstrate that FGFR-induced CX3CL1 is sufficient to recruit CX3CR1-expressing macrophages in vitro. Finally, blocking CX3CR1 in vivo leads to decreased iFGFR1-induced macrophage recruitment, which correlates with decreased angiogenesis. While CX3CL1 is a known target of FGF signaling in the wound healing environment, these studies demonstrate that FGFR activation also leads to induction of CX3CL1 in a tumor setting. Furthermore, these results define a novel role for CX3CL1 in promoting macrophage recruitment during mammary tumor formation, suggesting that the CX3CL1/CX3CR1 axis may represent a potential therapeutic approach for targeting breast cancers associated

  20. Searching Novel Therapeutic Targets for Scleroderma: P2X7-Receptor Is Up-regulated and Promotes a Fibrogenic Phenotype in Systemic Sclerosis Fibroblasts

    Directory of Open Access Journals (Sweden)

    Daniela Gentile

    2017-09-01

    Full Text Available Objectives: Systemic sclerosis (SSc is a connective tissue disorder presenting fibrosis of the skin and internal organs, for which no effective treatments are currently available. Increasing evidence indicates that the P2X7 receptor (P2X7R, a nucleotide-gated ionotropic channel primarily involved in the inflammatory response, may also have a key role in the development of tissue fibrosis in different body districts. This study was aimed at investigating P2X7R expression and function in promoting a fibrogenic phenotype in dermal fibroblasts from SSc patients, also analyzing putative underlying mechanistic pathways.Methods: Fibroblasts were isolated by skin biopsy from 9 SSc patients and 8 healthy controls. P2X7R expression, and function (cytosolic free Ca2+ fluxes, α-smooth muscle actin [α-SMA] expression, cell migration, and collagen release were studied. Moreover, the role of cytokine (interleukin-1β, interleukin-6 and connective tissue growth factor (CTGF production, and extracellular signal-regulated kinases (ERK activation in mediating P2X7R-dependent pro-fibrotic effects in SSc fibroblasts was evaluated.Results: P2X7R expression and Ca2+ permeability induced by the selective P2X7R agonist 2′-3′-O-(4-benzoylbenzoylATP (BzATP were markedly higher in SSc than control fibroblasts. Moreover, increased αSMA expression, cell migration, CTGF, and collagen release were observed in lipopolysaccharides-primed SSc fibroblasts after BzATP stimulation. While P2X7-induced cytokine changes did not affect collagen production, it was completely abrogated by inhibition of the ERK pathway.Conclusion: In SSc fibroblasts, P2X7R is overexpressed and its stimulation induces Ca2+-signaling activation and a fibrogenic phenotype characterized by increased migration and collagen production. These data point to the P2X7R as a potential, novel therapeutic target for controlling exaggerated collagen deposition and tissue fibrosis in patients with SSc.

  1. Searching Novel Therapeutic Targets for Scleroderma: P2X7-Receptor Is Up-regulated and Promotes a Fibrogenic Phenotype in Systemic Sclerosis Fibroblasts

    Science.gov (United States)

    Gentile, Daniela; Lazzerini, Pietro E.; Gamberucci, Alessandra; Natale, Mariarita; Selvi, Enrico; Vanni, Francesca; Alì, Alessandra; Taddeucci, Paolo; Del-Ry, Silvia; Cabiati, Manuela; Della-Latta, Veronica; Abraham, David J.; Morales, Maria A.; Fulceri, Rosella; Laghi-Pasini, Franco; Capecchi, Pier L.

    2017-01-01

    Objectives: Systemic sclerosis (SSc) is a connective tissue disorder presenting fibrosis of the skin and internal organs, for which no effective treatments are currently available. Increasing evidence indicates that the P2X7 receptor (P2X7R), a nucleotide-gated ionotropic channel primarily involved in the inflammatory response, may also have a key role in the development of tissue fibrosis in different body districts. This study was aimed at investigating P2X7R expression and function in promoting a fibrogenic phenotype in dermal fibroblasts from SSc patients, also analyzing putative underlying mechanistic pathways. Methods: Fibroblasts were isolated by skin biopsy from 9 SSc patients and 8 healthy controls. P2X7R expression, and function (cytosolic free Ca2+ fluxes, α-smooth muscle actin [α-SMA] expression, cell migration, and collagen release) were studied. Moreover, the role of cytokine (interleukin-1β, interleukin-6) and connective tissue growth factor (CTGF) production, and extracellular signal-regulated kinases (ERK) activation in mediating P2X7R-dependent pro-fibrotic effects in SSc fibroblasts was evaluated. Results: P2X7R expression and Ca2+ permeability induced by the selective P2X7R agonist 2′-3′-O-(4-benzoylbenzoyl)ATP (BzATP) were markedly higher in SSc than control fibroblasts. Moreover, increased αSMA expression, cell migration, CTGF, and collagen release were observed in lipopolysaccharides-primed SSc fibroblasts after BzATP stimulation. While P2X7-induced cytokine changes did not affect collagen production, it was completely abrogated by inhibition of the ERK pathway. Conclusion: In SSc fibroblasts, P2X7R is overexpressed and its stimulation induces Ca2+-signaling activation and a fibrogenic phenotype characterized by increased migration and collagen production. These data point to the P2X7R as a potential, novel therapeutic target for controlling exaggerated collagen deposition and tissue fibrosis in patients with SSc. PMID:28955239

  2. Inhibition of plaque progression and promotion of plaque stability by glucagon-like peptide-1 receptor agonist: Serial in vivo findings from iMap-IVUS in Watanabe heritable hyperlipidemic rabbits.

    Science.gov (United States)

    Sudo, Mitsumasa; Li, Yuxin; Hiro, Takafumi; Takayama, Tadateru; Mitsumata, Masako; Shiomi, Masashi; Sugitani, Masahiko; Matsumoto, Taro; Hao, Hiroyuki; Hirayama, Atsushi

    2017-10-01

    Glucagon-like peptide-1 (GLP-1) is thought to inhibit development of aortic atherosclerosis and plaque formation. However, whether GLP-1 stabilizes fully developed atherosclerotic plaque or alters the complicated plaque composition remains unclarified. Ten Watanabe heritable hyperlipidemic (WHHL) rabbits were divided into GLP-1 receptor agonist treatment group and control group. After confirmation of atherosclerotic plaques in brachiocephalic arteries by iMap intravascular ultrasound (iMAP-IVUS), GLP-1 receptor agonist lixisenatide was administered to WHHL rabbits at 30 nmoL/kg/day for 12 weeks by osmotic pump. An equal volume of normal saline was administered in a control group. After evaluation by iMAP-IVUS at 12 weeks, brachiocephalic arteries were harvested for pathological histological analysis. iMAP-IVUS analysis revealed larger fibrotic plaque components and smaller necrotic and calcified plaque components in the GLP-1 group than in the control group; %fibrotic area: 66.30 ± 2.06% vs. 75.14 ± 2.62%, p GLP-1 receptor agonist might modify plaque composition and increase plaque stability. Histological analysis confirmed that GLP-1 receptor agonist treatment improved smooth muscle cell (SMC)-rich plaque with increased fibrotic content. Furthermore, plaque macrophage infiltration and calcification were significantly reduced by GLP-1 receptor agonist treatment; %SMC area: 6.93 ± 0.31% vs. 8.14 ± 0.48%, p = 0.02; %macrophage area: 9.11 ± 0.80% vs. 6.19 ± 0.85%, p GLP-1 receptor agonist inhibited plaque progression and promoted plaque stabilization by inhibiting plaque growth and modifying plaque composition. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. Persistent inflammation-induced up-regulation of brain-derived neurotrophic factor (BDNF) promotes synaptic delivery of α-amino-3-hydroxy-5-methyl-4-isoxazolepropionic acid receptor GluA1 subunits in descending pain modulatory circuits.

    Science.gov (United States)

    Tao, Wenjuan; Chen, Quan; Zhou, Wenjie; Wang, Yunping; Wang, Lu; Zhang, Zhi

    2014-08-08

    The enhanced AMPA receptor phosphorylation at GluA1 serine 831 sites in the central pain-modulating system plays a pivotal role in descending pain facilitation after inflammation, but the underlying mechanisms remain unclear. We show here that, in the rat brain stem, in the nucleus raphe magnus, which is a critical relay in the descending pain-modulating system of the brain, persistent inflammatory pain induced by complete Freund adjuvant (CFA) can enhance AMPA receptor-mediated excitatory postsynaptic currents and the GluA2-lacking AMPA receptor-mediated rectification index. Western blot analysis showed an increase in GluA1 phosphorylation at Ser-831 but not at Ser-845. This was accompanied by an increase in distribution of the synaptic GluA1 subunit. In parallel, the level of histone H3 acetylation at bdnf gene promoter regions was reduced significantly 3 days after CFA injection, as indicated by ChIP assays. This was correlated with an increase in BDNF mRNA levels and BDNF protein levels. Sequestering endogenous extracellular BDNF with TrkB-IgG in the nucleus raphe magnus decreased AMPA receptor-mediated synaptic transmission and GluA1 phosphorylation at Ser-831 3 days after CFA injection. Under the same conditions, blockade of TrkB receptor functions, phospholipase C, or PKC impaired GluA1 phosphorylation at Ser-831 and decreased excitatory postsynaptic currents mediated by GluA2-lacking AMPA receptors. Taken together, these results suggest that epigenetic up-regulation of BDNF by peripheral inflammation induces GluR1 phosphorylation at Ser-831 sites through activation of the phospholipase C-PKC signaling cascade, leading to the trafficking of GluA1 to pain-modulating neuronal synapses. © 2014 by The American Society for Biochemistry and Molecular Biology, Inc.

  4. Antibody Probes to Estrogen Receptor-Alpha Transcript-Specific Upstream Peptides: Alternate ER-Alpha Promoter Use and Breast Cancer Etiology/Outcome

    National Research Council Canada - National Science Library

    Pentecost, Brian

    2002-01-01

    Positive Estrogen Receptor alpha (ER) status correlates with a reduced incidence of breast cancer recurrence in the first years after resection of tumors, and predicts a favorable response to adjuvant anti-estrogens...

  5. Antibody Probes to Estrogen Receptor-alpha Transcript-Specific Upstream Peptides: Alternates ER-alpha Promoter Use and Breast Cancer Etiology/Outcome

    Science.gov (United States)

    2005-05-01

    cells recovered in the expressed milk of lactating healthy donors as part of a biomarkers study. Preparing for potential handling of ductal lavage...specificity for the assay (Fig. 17). It is quite feasible to isolate sufficient cells from milk samples and our potential collaorator’s lab was able...Speirs, V., 2001. Expression of alternatively spliced estrogen Uht , R.M., Webb, P., 2000. Estrogen receptor pathways to AP-I. J. receptor alpha mRNAs is

  6. The far and distal enhancers in the CYP3A4 gene co-ordinate the proximal promoter in responding similarly to the pregnane X receptor but differentially to hepatocyte nuclear factor-4alpha.

    Science.gov (United States)

    Liu, Fu-Jun; Song, Xiulong; Yang, Dongfang; Deng, Ruitang; Yan, Bingfang

    2008-01-01

    CYP3A4 (cytochrome P450 3A4) is involved in the metabolism of more than 50% of drugs and other xenobiotics. The expression of CYP3A4 is induced by many structurally dissimilar compounds. The PXR (pregnane X receptor) is recognized as a key regulator for the induction, and the PXR-directed transactivation of the CYP3A4 gene is achieved through a co-ordinated mechanism of the distal module with the proximal promoter. Recently, a far module was found to support constitutive expression of CYP3A4. The far module, like the distal module, is structurally clustered by a PXR response element (F-ER6) and elements recognized by HNF-4alpha (hepatocyte nuclear receptor-4alpha). We hypothesized that the far module supports PXR transactivation of the CYP3A4 gene. Consistent with the hypothesis, fusion of the far module to the proximal promoter of CYP3A4 markedly increased rifampicin-induced reporter activity. The increase was synergistically enhanced when both the far and distal modules were fused to the proximal promoter. The increase, however, was significantly reduced when the F-ER6 was disrupted. Chromatin immunoprecipitation detected the presence of PXR in the far module. Interestingly, HNF-4alpha increased the activity of the distal-proximal fused promoter, but decreased the activity of the far-proximal fused promoter. Given the fact that induction of CYP3A4 represents an important detoxification mechanism, the functional redundancy and synergistic interaction in supporting PXR transactivation suggest that the far and distal modules ensure the induction of CYP3A4 during chemical insults. The difference in responding to HNF-4alpha suggests that the magnitude of the induction is under control through various transcriptional networks.

  7. Activation of 5-HT2a receptors in the basolateral amygdala promotes defeat-induced anxiety and the acquisition of conditioned defeat in Syrian hamsters.

    Science.gov (United States)

    Clinard, Catherine T; Bader, Lauren R; Sullivan, Molly A; Cooper, Matthew A

    2015-03-01

    Conditioned defeat is a model in Syrian hamsters (Mesocricetus auratus) in which normal territorial aggression is replaced by increased submissive and defensive behavior following acute social defeat. The conditioned defeat response involves both a fear-related memory for a specific opponent as well as anxiety-like behavior indicated by avoidance of novel conspecifics. We have previously shown that systemic injection of a 5-HT2a receptor antagonist reduces the acquisition of conditioned defeat. Because neural activity in the basolateral amygdala (BLA) is critical for the acquisition of conditioned defeat and BLA 5-HT2a receptors can modulate anxiety but have a limited effect on emotional memories, we investigated whether 5-HT2a receptor modulation alters defeat-induced anxiety but not defeat-related memories. We injected the 5-HT2a receptor antagonist MDL 11,939 (0 mM, 1.7 mM or 17 mM) or the 5-HT2a receptor agonist TCB-2 (0 mM, 8 mM or 80 mM) into the BLA prior to social defeat. We found that injection of MDL 11,939 into the BLA impaired acquisition of the conditioned defeat response and blocked defeat-induced anxiety in the open field, but did not significantly impair avoidance of former opponents in the Y-maze. Furthermore, we found that injection of TCB-2 into the BLA increased the acquisition of conditioned defeat and increased anxiety-like behavior in the open field, but did not alter avoidance of former opponents. Our data suggest that 5-HT2a receptor signaling in the BLA is both necessary and sufficient for the development of conditioned defeat, likely via modulation of defeat-induced anxiety. Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Cannabinoid receptor-2 (CB2) agonist ameliorates colitis in IL-10{sup −/−} mice by attenuating the activation of T cells and promoting their apoptosis

    Energy Technology Data Exchange (ETDEWEB)

    Singh, Udai P.; Singh, Narendra P. [Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC 29208 (United States); Singh, Balwan [National Primate Research Center, Emory University, Atlanta GA 30329 (United States); Price, Robert L. [Department of Cell and Developmental Biology, University of South Carolina, Columbia, SC 29208 (United States); Nagarkatti, Mitzi [Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC 29208 (United States); Nagarkatti, Prakash S., E-mail: Prakash.Nagarkatti@uscmed.sc.edu [Pathology, Microbiology and Immunology, School of Medicine, University of South Carolina, Columbia, SC 29208 (United States)

    2012-01-15

    Inflammatory bowel disease (IBD) is a chronic intestinal inflammation caused by hyperactivated effector immune cells that produce pro-inflammatory cytokines. Recent studies have shown that the cannabinoid system may play a critical role in mediating protection against intestinal inflammation. However, the effect of cannabinoid receptor induction after chronic colitis progression has not been investigated. Here, we investigate the effect of cannabinoid receptor-2 (CB2) agonist, JWH-133, after chronic colitis in IL-10{sup −/−} mice. JWH-133 effectively attenuated the overall clinical score, and reversed colitis-associated pathogenesis and decrease in body weight in IL-10{sup −/−} mice. After JWH-133 treatment, the percentage of CD4{sup +} T cells, neutrophils, mast cells, natural killer (NK1.1) cells, and activated T cells declined in the intestinal lamina propria (LP) and mesenteric lymph nodes (MLN) of mice with chronic colitis. JWH-133 was also effective in ameliorating dextran sodium sulfate (DSS)-induced colitis. In this model, JWH-133 reduced the number and percentage of macrophages and IFN-γ expressing cells that were induced during colitis progression. Treatment with aminoalkylindole 6-iodo-pravadoline (AM630), a CB2 receptor antagonist, reversed the colitis protection provided by JWH-133 treatment. Also, activated T cells were found to undergo apoptosis following JWH-133 treatment both in-vivo and in-vitro. These findings suggest that JWH-133 mediates its effect through CB2 receptors, and ameliorates chronic colitis by inducing apoptosis in activated T cells, reducing the numbers of activated T cells, and suppressing induction of mast cells, NK cells, and neutrophils at sites of inflammation in the LP. These results support the idea that the CB2 receptor agonists may serve as a therapeutic modality against IBD. -- Highlights: ► JWH-133, a cannnabinoid receptor-2 agonist ameliorates experimental colitis. ► JWH-133 suppressed inflammation and

  9. Transcriptional Inhibition of Matrix Metal loproteinase 9 (MMP-9 Activity by a c-fos/Estrogen Receptor Fusion Protein is Mediated by the Proximal AP-1 Site of the MMP-9 Promoter and Correlates with Reduced Tumor Cell Invasion

    Directory of Open Access Journals (Sweden)

    David L. Crowe

    1999-10-01

    Full Text Available Tumor cell invasion of basement membranes is one of the hallmarks of malignant transformation. Tumor cells secrete proteolytic enzymes known as matrix metalloproteinases (MMPs which degrade extracellular matrix molecules. Increased expression of MMP-9 has been associated with acquisition of invasive phenotype in many tumors. However, multiple mechanisms for regulation of MMP-9 gene expression by tumor cell lines have been proposed. A number of transcription factor binding sites have been characterized in the upstream regulatory region of the MMP-9 gene, including those for AP-1. To determine how a specific AP-1 family member, c-fos, regulates MMP-9 promoter activity through these sites, we used an expression vector containing the c-fos coding region fused to the estrogen receptor (ER ligand binding domain. This construct is activated upon binding estradiol. Stable expression of this construct in ER negative squamous cell carcinoma (SCC lines produced an estradiol dependent decrease in the number of cells that migrated through a reconstituted basement membrane. This decreased invasiveness was accompanied by estradiol dependent downregulation of MMP-9 activity as determined by gelatin zymography. Estradiol also produced transcriptional downregulation of an MMP-9 promoter construct in cells transiently transfected with the c-fosER expression vector. This downregulation was mediated by the AP-1 site at —79 by in the MMP-9 promoter. We concluded that the proximal AP-1 site mediated the transcriptional downregulation of the MMP-9 promoter by a conditionally activated c-fos fusion protein.

  10. A neural cell adhesion molecule-derived fibroblast growth factor receptor agonist, the FGL-peptide, promotes early postnatal sensorimotor development and enhances social memory retention

    DEFF Research Database (Denmark)

    Secher, Thomas; Novitskaia, V; Berezin, Vladimir

    2006-01-01

    with the fibroblast growth factor receptor (FGFR). A 15-amino-acid long peptide, the FG loop (FGL) peptide, that is derived from the second F3 module of NCAM has been found to activate FGFR1. We here report that the FGL peptide, when administered intranasally to newborn rats, accelerated early postnatal development...

  11. The Common Follicle-Stimulating Hormone Receptor (FSHR) Promoter Polymorphism FSHR -29G > A Affects Androgen Production in Normal Human Small Antral Follicles

    DEFF Research Database (Denmark)

    Borgbo, Tanni; Klučková, Hana; Macek, Milan

    2017-01-01

    Follicle-stimulating hormone receptors (FSHRs) are almost exclusively expressed on granulosa cells, and FSH action is probably most clearly reflected in intrafollicular hormone milieu of antral follicles. Little is known about the possible effects of the common single nucleotide polymorphism (SNP...

  12. TNF-alpha promoter, Nod2 and toll-like receptor-4 polymorphisms and the in vivo and ex vivo response to endotoxin

    NARCIS (Netherlands)

    Schippers, Emile F.; van 't Veer, Cornelis; van Voorden, Sjaak; Martina, Cerithsa A. E.; le Cessie, Saskia; van Dissel, Jaap T.

    2004-01-01

    Humans exhibit substantial inter-individual differences in TNF-alpha production upon endotoxin stimulation. To determine to what extent the lipopolysaccharide-induced TNF-alpha production capacity in vivo and ex vivo is determined by polymorphisms in toll-like receptor-4 (TLR4), the TNF-alpha

  13. IL-17 promotes bone erosion in murine collagen-induced arthritis through loss of the receptor activator of NF-kappa B ligand/osteoprotegerin balance.

    NARCIS (Netherlands)

    Lubberts, G.J.H.; Bersselaar, L.A.M. van den; Oppers-Walgreen, B.; Schwarzenberger, P.; Coonen-de Roo, C.J.; Kolls, J.; Joosten, L.A.B.; Berg, W.B. van den

    2003-01-01

    IL-17 is a T cell-derived proinflammatory cytokine in experimental arthritis and is a stimulator of osteoclastogenesis in vitro. In this study, we report the effects of IL-17 overexpression (AdIL-17) in the knee joint of type II collagen-immunized mice on bone erosion and synovial receptor activator

  14. Activation of melatonin receptor (MT1/2) promotes P-gp transporter in methamphetamine-induced toxicity on primary rat brain microvascular endothelial cells.

    Science.gov (United States)

    Jumnongprakhon, Pichaya; Sivasinprasasn, Sivanan; Govitrapong, Piyarat; Tocharus, Chainarong; Tocharus, Jiraporn

    2017-06-01

    Melatonin has been known as a neuroprotective agent for the central nervous system (CNS) and the blood-brain barrier (BBB), which is the primary structure that comes into contact with several neurotoxins including methamphetamine (METH). Previous studies have reported that the activation of melatonin receptors (MT1/2) by melatonin could protect against METH-induced toxicity in brain endothelial cells via several mechanisms. However, its effects on the P-glycoprotein (P-gp) transporter, the active efflux pump involved in cell homeostasis, are still unclear. Thus, this study investigated the role of melatonin and its receptors on the METH-impaired P-gp transporter in primary rat brain microvascular endothelial cells (BMVECs). The results showed that METH impaired the function of the P-gp transporter, significantly decreasing the efflux of Rho123 and P-gp expression, which caused a significant increase in the intracellular accumulation of Rho123, and these responses were reversed by the interaction of melatonin with its receptors. Blockade of the P-gp transporter by verapamil caused oxidative stress, apoptosis, and cell integrity impairment after METH treatment, and these effects could be reversed by melatonin. Our results, together with previous findings, suggest that the interaction of melatonin with its receptors protects against the effects of the METH-impaired P-gp transporter and that the protective role in METH-induced toxicity was at least partially mediated by the regulation of the P-gp transporter. Thus, melatonin and its receptors (MT1/2) are essential for protecting against BBB impairment caused by METH. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Histamine Increases Neuronal Excitability and Sensitivity of the Lateral Vestibular Nucleus and Promotes Motor Behaviors via HCN Channel Coupled to H2 Receptor

    OpenAIRE

    Li, Bin; Zhang, Xiao-Yang; Yang, Ai-Hong; Peng, Xiao-Chun; Chen, Zhang-Peng; Zhou, Jia-Yuan; Chan, Ying-Shing; Wang, Jian-Jun; Zhu, Jing-Ning

    2017-01-01

    Histamine and histamine receptors in the central nervous system actively participate in the modulation of motor control. In clinic, histamine-related agents have traditionally been used to treat vestibular disorders. Immunohistochemical studies have revealed a distribution of histaminergic afferents in the brainstem vestibular nuclei, including the lateral vestibular nucleus (LVN), which is critical for adjustment of muscle tone and vestibular reflexes. However, the mechanisms underlying the ...

  16. Biomaterial-enabled delivery of SDF-1α at the ventral side of breast cancer cells reveals a crosstalk between cell receptors to promote the invasive phenotype.

    Science.gov (United States)

    Liu, Xi Qiu; Fourel, Laure; Dalonneau, Fabien; Sadir, Rabia; Leal, Salome; Lortat-Jacob, Hugues; Weidenhaupt, Marianne; Albiges-Rizo, Corinne; Picart, Catherine

    2017-05-01

    The SDF-1α chemokine (CXCL12) is a potent bioactive chemoattractant known to be involved in hematopoietic stem cell homing and cancer progression. The associated SDF-1α/CXCR4 receptor signaling is a hallmark of aggressive tumors, which can metastasize to distant sites such as lymph nodes, lung and bone. Here, we engineered a biomimetic tumoral niche made of a thin and soft polyelectrolyte film that can retain SDF-1α to present it, in a spatially-controlled manner, at the ventral side of the breast cancer cells. Matrix-bound SDF-1α but not soluble SDF-1α induced a striking increase in cell spreading and migration in a serum-containing medium, which was associated with the formation of lamellipodia and filopodia in MDA-MB231 cells and specifically mediated by CXCR4. Other Knockdown and inhibition experiments revealed that CD44, the major hyaluronan receptor, acted in concert, via a spatial coincidence, to drive a specific matrix-bound SDFα-induced cell response associated with ERK signaling. In contrast, the β1 integrin adhesion receptor played only a minor role on cell polarity. The CXCR4/CD44 mediated cellular response to matrix-bound SDF-1α involved the Rac1 RhoGTPase and was sustained solely in the presence of matrix-bound SDFα, in contrast with the transient signaling observed in response to soluble SDF-1α. Our results highlight that a biomimetic tumoral niche enables to reveal potent cellular effects and so far hidden molecular mechanisms underlying the breast cancer response to chemokines. These results open new insights for the design of future innovative therapies in metastatic cancers, by inhibiting CXCR4-mediated signaling in the tumoral niche via dual targeting of receptors (CXCR4 and CD44) or of associated signaling molecules (CXCR4 and Rac1). Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. αvβ6- and αvβ8-integrins serve as interchangeable receptors for HSV gH/gL to promote endocytosis and activation of membrane fusion.

    Directory of Open Access Journals (Sweden)

    Tatiana Gianni

    Full Text Available Herpes simplex virus (HSV--and herpesviruses in general--encode for a multipartite entry/fusion apparatus. In HSV it consists of the HSV-specific glycoprotein D (gD, and three additional glycoproteins, gH/gL and gB, conserved across the Herpesviridae family and responsible for the execution of fusion. According to the current model, upon receptor binding, gD propagates the activation to gH/gL and to gB in a cascade fashion. Questions remain about how the cascade of activation is controlled and how it is synchronized with virion endocytosis, to avoid premature activation and exhaustion of the glycoproteins. We considered the possibility that such control might be carried out by as yet unknown receptors. Indeed, receptors for HSV gB, but not for gH/gL, have been described. In other members of the Herpesviridae family, such as Epstein-Barr virus, integrin receptors bind gH/gL and trigger conformational changes in the glycoproteins. We report that αvβ6- and αvβ8-integrins serve as receptors for HSV entry into experimental models of keratinocytes and other epithelial and neuronal cells. Evidence rests on loss of function experiments, in which integrins were blocked by antibodies or silenced, and gain of function experiments in which αvβ6-integrin was expressed in integrin-negative cells. αvβ6- and αvβ8-integrins acted independently and are thus interchangeable. Both bind gH/gL with high affinity. The interaction profoundly affects the route of HSV entry and directs the virus to acidic endosomes. In the case of αvβ8, but not αvβ6-integrin, the portal of entry is located at lipid microdomains and requires dynamin 2. Thus, a major role of αvβ6- or αvβ8-integrin in HSV infection appears to be to function as gH/gL receptors and to promote virus endocytosis. We propose that placing the gH/gL activation under the integrin trigger point enables HSV to synchronize virion endocytosis with the cascade of glycoprotein activation that culminates

  18. Inducible expression of enhanced green fluorescent protein by interleukin-1α, interleukin-1β and Toll-like receptor 2 promoters in goat mammary epithelial cells in response to bacterial challenges.

    Science.gov (United States)

    Ru, Kun; Su, Feng; Zheng, Yuemao; Zhang, Yijun; Luo, Yan; Guo, Zekun; He, Xiaoli; Liu, Xin; Zhang, Jingcheng; Liu, Jun; Zhang, Yong

    2015-01-01

    The development of a bacteria-inducible expression system has several advantages compared with persistent expression of anti-bacterial proteins in milk to prevent and treat mastitis. The present study determined whether mastitis responsive promoters could regulate enhanced green fluorescent protein (EGFP) expression in goat mammary epithelial cells (GMECs) in response to challenges with Escherichia coli, Staphylococcus aureus or Streptococcus agalactiae. The level of expression of interleukin (IL)-1α was significantly increased in GMECs challenged with E. coli, S. aureus or S. agalactiae compared with untreated GMECs. IL-1β was induced by E. coli and S. aureus, while Toll-like receptor 2 (TLR2) was induced by E. coli only. GMECs were transfected with IL-1α, IL-1β and TLR2 promoter-EGFP reporter gene lentiviral expression vectors and the levels of expression of EGFP were measured by flow cytometry and Western blot analysis after bacterial challenge. EGFP expression driven by the IL-1α and IL-1β promoters was higher in GMECs challenged with E. coli, S. aureus or S. agalactiae than in untreated GMECs. There were no differences in EGFP expression driven by the TLR2 promoter between GMECs challenged with S. aureus or S. agalactiae and untreated GMECs, but EGFP expression was significantly increased in GMECs challenged with E. coli. Overall, these results indicate that the promoters of some bacteria-inducible genes can regulate EGFP expression in GMECs in response to bacterial challenges. This bacteria-inducible expression strategy could be used for production of mastitis resistant animals by regulating the expression of anti-bacterial proteins in the mammary gland. Copyright © 2014 Elsevier Ltd. All rights reserved.

  19. Insulin receptors

    International Nuclear Information System (INIS)

    Kahn, C.R.; Harrison, L.C.

    1988-01-01

    This book contains the proceedings on insulin receptors. Part A: Methods for the study of structure and function. Topics covered include: Method for purification and labeling of insulin receptors, the insulin receptor kinase, and insulin receptors on special tissues

  20. Interaction between the thyroid hormone receptor and co-factors on the promoter of the gene encoding phospho enol pyruvate carboxykinase

    NARCIS (Netherlands)

    Schmidt, E. D.; van Beeren, M.; Glass, C. K.; Wiersinga, W. M.; Lamers, W. H.

    1993-01-01

    Using transient transfection studies we localized a thyroid hormone-responsive element on the promoter of the rat phospho-enol pyruvate carboxykinase gene between 355 and 174 bp upstream of the transcription start site. DNAse 1 footprinting analysis within this region showed that a 28 bp fragment at

  1. Histone Demethylation and Toll-like Receptor 8-Dependent Cross-Talk in Monocytes Promotes Transdifferentiation of Fibroblasts in Systemic Sclerosis Via Fra-2

    NARCIS (Netherlands)

    Ciechomska, Marzena; O'Reilly, Steven; Przyborski, Stefan; Oakley, Fiona; Bogunia-Kubik, Katarzyna; Van Laar, Jacob M.

    2016-01-01

    Objective To investigate whether epigenetic changes can modulate monocytes to produce tissue inhibitor of metalloproteinases 1 (TIMP-1) via Fra-2 (an activator protein 1 [AP-1] family member), a novel downstream mediator that promotes fibrogenesis. Methods AP-1 transcription factors and TIMP-1

  2. Enzymatically Modified Low-Density Lipoprotein Promotes Foam Cell Formation in Smooth Muscle Cells via Macropinocytosis and Enhances Receptor-Mediated Uptake of Oxidized Low-Density Lipoprotein.

    Science.gov (United States)

    Chellan, Bijoy; Reardon, Catherine A; Getz, Godfrey S; Hofmann Bowman, Marion A

    2016-06-01

    Enzyme-modified nonoxidized low-density lipoprotein (ELDL) is present in human atherosclerotic lesions. Our objective is to understand the mechanisms of ELDL uptake and its effects on vascular smooth muscle cells (SMC). Transformation of murine aortic SMCs into foam cells in response to ELDL was analyzed. ELDL, but not acetylated or oxidized LDL, was potent in inducing SMC foam cell formation. Inhibitors of macropinocytosis (LY294002, wortmannin, amiloride) attenuated ELDL uptake. In contrast, inhibitors of receptor-mediated endocytosis (dynasore, sucrose) and inhibitor of caveolae-/lipid raft-mediated endocytosis (filipin) had no effect on ELDL uptake in SMC, suggesting that macropinocytosis is the main mechanism of ELDL uptake by SMC. Receptor for advanced glycation end products (RAGE) is not obligatory for ELDL-induced SMC foam cell formation, but primes SMC for the uptake of oxidized LDL in a RAGE-dependent manner. ELDL increased intracellular reactive oxygen species, cytosolic calcium, and expression of lectin-like oxidized LDL receptor-1 in wild-type SMC but not in RAGE(-/-) SMC. The macropinocytotic uptake of ELDL is regulated predominantly by intracellular calcium because ELDL uptake was completely inhibited by pretreatment with the calcium channel inhibitor lacidipine in wild-type and RAGE(-/-) SMC. This is in contrast to pretreatment with PI3 kinase inhibitors which completely prevented ELDL uptake in RAGE(-/-) SMC, but only partially in wild-type SMC. ELDL is highly potent in inducing foam cells in murine SMC. ELDL endocytosis is mediated by calcium-dependent macropinocytosis. Priming SMC with ELDL enhances the uptake of oxidized LDL. © 2016 American Heart Association, Inc.

  3. Purple sweet potato color attenuates domoic acid-induced cognitive deficits by promoting estrogen receptor-α-mediated mitochondrial biogenesis signaling in mice.

    Science.gov (United States)

    Lu, Jun; Wu, Dong-Mei; Zheng, Yuan-Lin; Hu, Bin; Cheng, Wei; Zhang, Zi-Feng

    2012-02-01

    Recent findings suggest that endoplasmic reticulum stress may be involved in the pathogenesis of domoic acid-induced neurodegeneration. Purple sweet potato color, a class of naturally occurring anthocyanins, has beneficial health and biological effects. Recent studies have also shown that anthocyanins have estrogenic activity and can enhance estrogen receptor-α expression. In this study, we evaluated the effect of purple sweet potato color on cognitive deficits induced by hippocampal mitochondrial dysfunction in domoic acid-treated mice and explored the potential mechanisms underlying this effect. Our results showed that the oral administration of purple sweet potato color to domoic acid-treated mice significantly improved their behavioral performance in a step-through passive avoidance task and a Morris water maze task. These improvements were mediated, at least in part, by a stimulation of estrogen receptor-α-mediated mitochondrial biogenesis signaling and by decreases in the expression of p47phox and gp91phox. Decreases in reactive oxygen species and protein carbonylation were also observed, along with a blockade of the endoplasmic reticulum stress pathway. Furthermore, purple sweet potato color significantly suppressed endoplasmic reticulum stress-induced apoptosis, which prevented neuron loss and restored the expression of memory-related proteins. However, knockdown of estrogen receptor-α using short hairpin RNA only partially blocked the neuroprotective effects of purple sweet potato color in the hippocampus of mice cotreated with purple sweet potato color and domoic acid, indicating that purple sweet potato color acts through multiple pathways. These results suggest that purple sweet potato color could be a possible candidate for the prevention and treatment of cognitive deficits in excitotoxic and other brain disorders. Crown Copyright © 2011. Published by Elsevier Inc. All rights reserved.

  4. Lowbush cranberry acts through DAF-16/FOXO signaling to promote increased lifespan and axon branching in aging posterior touch receptor neurons.

    Science.gov (United States)

    Scerbak, Courtney; Vayndorf, Elena; Hernandez, Alicia; McGill, Colin; Taylor, Barbara

    2018-05-01

    Medicinal berries are appreciated for their health benefits, in traditional ecological knowledge and nutrition science. Determining the cellular mechanisms underlying the effects of berry supplementation may contribute to our understanding of aging. Here, we report that lowbush cranberry (Vaccinium vitis-idaea) treatment causes marked nuclear localization of the central aging-related transcription factor DAF-16/FOXO in aged Caenorhabditis elegans. Further, functional DAF-16 is required for the lifespan extension, improved mechanosensation, and posterior touch receptor neuron morphological changes induced by lowbush cranberry treatments. DAF-16 is not observed in nuceli nor required for lifespan extension in lifespan-extending Alaskan blueberry treatments and, while DAF-16 is not visibly induced into the nucleus in lifespan-extending Alaskan chaga treatments, it is required for chaga-induced lifespan extension. These findings underscore the importance of DAF-16 in the aging of whole organisms and touch receptor neurons and also, importantly, indicate that this critical pathway is not always activated upon consumption of functional foods that impact aging.

  5. Synthetic Nanoparticles That Promote Tumor Necrosis Factor Receptor 2 Expressing Regulatory T Cells in the Lung and Resistance to Allergic Airways Inflammation

    Directory of Open Access Journals (Sweden)

    Rohimah Mohamud

    2017-12-01

    Full Text Available Synthetic glycine coated 50 nm polystyrene nanoparticles (NP (PS50G, unlike ambient NP, do not promote pulmonary inflammation, but instead, render lungs resistant to the development of allergic airway inflammation. In this study, we show that PS50G modulate the frequency and phenotype of regulatory T cells (Treg in the lung, specifically increasing the proportion of tumor necrosis factor 2 (TNFR2 expressing Treg. Mice pre-exposed to PS50G, which were sensitized and then challenged with an allergen a month later, preferentially expanded TNFR2+Foxp3+ Treg, which further expressed enhanced levels of latency associated peptide and cytotoxic T-lymphocyte associated molecule-4. Moreover, PS50G-induced CD103+ dendritic cell activation in the lung was associated with the proliferative expansion of TNFR2+Foxp3+ Treg. These findings provide the first evidence that engineered NP can promote the selective expansion of maximally suppressing TNFR2+Foxp3+ Treg and further suggest a novel mechanism by which NP may promote healthy lung homeostasis.

  6. 17β-estradiol promotes the invasion and migration of nuclear estrogen receptor-negative breast cancer cells through cross-talk between GPER1 and CXCR1.

    Science.gov (United States)

    Jiang, Qi-Feng; Wu, Ting-Ting; Yang, Jun-Yan; Dong, Chao-Ran; Wang, Ni; Liu, Xiao-Hua; Liu, Zhi-Min

    2013-11-01

    G protein-coupled estrogen receptor 1 (GPER1) is widely expressed in human breast cancers correlating with increased tumor size and malignancy. Although estrogen signaling via GPER1 was extensively studied in recent years, the underlying molecular mechanism of GPER1-associated metastasis of breast cancer still remains unclear. In this study, the main aims were focused on the potential role of GPER1 in regulating migration and invasion of nuclear estrogen receptor (ER)-negative breast cancer cells upon 17β-estradiol (E2) stimulation and the involved signaling pathway. Key events in estrogen signaling were chosen for our studies, such as the activation of ERK and AKT, nuclear translocation of NF-κB and secretion of Interleukin-8 (IL-8). The migration and invasion activities upon E2 stimulation were also examined in ER-negative SKBR3 and BT-20 breast cancer cells. Compared with ER-positive MCF-7 breast cancer cells, both SKBR3 and BT-20 cells had very similar expression of GPER1, but relatively high expression of CXC receptor-1 (CXCR1), which is considered as an active regulator for cancer metastasis upon binding IL-8. Results showed that E2 facilitated the activation of ERK, AKT and NF-κB, which could be significantly attenuated by GPER1 blockage or knock-down in both SKBR3 and BT-20 cells. Moreover, increased secretion of IL-8 induced by E2 was also inhibited either by specific inhibitors for GPER1, ERK, AKT, and NF-κB, or by knock-down for GPER1. Furthermore, E2 could activate the migration and invasion of both SKBR3 and BT-20 cells, which in turn could also be inhibited by blocking GPER1, ERK, AKT, NF-κB, and CXCR1, respectively, or knock-down for GPER1 and CXCR1. In conclusion, we demonstrated that estrogen signaling via GPER1 associated with the metastasis of breast cancer, which might be through GPER1/ERK&AKT/NF-κB/IL-8/CXCR1 cascade. The cross-talk between GPER1 and CXCR1 could be another potential target for the therapy of metastatic breast cancer

  7. Villin promoter-mediated transgenic expression of transient receptor potential cation channel, subfamily V, member 6 (TRPV6) increases intestinal calcium absorption in wild-type and vitamin D receptor knockout mice.

    Science.gov (United States)

    Cui, Min; Li, Qiang; Johnson, Robert; Fleet, James C

    2012-10-01

    Transient receptor potential cation channel, subfamily V, member 6 (TRPV6) is an apical membrane calcium (Ca) channel in the small intestine proposed to be essential for vitamin D-regulated intestinal Ca absorption. Recent studies have challenged the proposed role for TRPV6 in Ca absorption. We directly tested intestinal TRPV6 function in Ca and bone metabolism in wild-type (WT) and vitamin D receptor knockout (VDRKO) mice. TRPV6 transgenic mice (TG) were made with intestinal epithelium-specific expression of a 3X Flag-tagged human TRPV6 protein. TG and VDRKO mice were crossed to make TG-VDRKO mice. Ca and bone metabolism was examined in WT, TG, VDRKO, and TG-VDRKO mice. TG mice developed hypercalcemia and soft tissue calcification on a chow diet. In TG mice fed a 0.25% Ca diet, Ca absorption was more than three-fold higher and femur bone mineral density (BMD) was 26% higher than WT. Renal 1α hydroxylase (CYP27B1) mRNA and intestinal expression of the natural mouse TRPV6 gene were reduced to intestine calbindin-D(9k) expression was elevated >15 times in TG mice. TG-VDRKO mice had high Ca absorption that prevented the low serum Ca, high renal CYP27B1 mRNA, low BMD, and abnormal bone microarchitecture seen in VDRKO mice. In addition, small intestinal calbindin D(9K) mRNA and protein levels were elevated in TG-VDRKO. Transgenic TRPV6 expression in intestine is sufficient to increase Ca absorption and bone density, even in VDRKO mice. VDR-independent upregulation of intestinal calbindin D(9k) in TG-VDRKO suggests this protein may buffer intracellular Ca during Ca absorption. © 2012 American Society for Bone and Mineral Research. Copyright © 2012 American Society for Bone and Mineral Research.

  8. [Electroacupuncture Combined with Clomiphene Promotes Pregnancy and Blastocyst Implantation Possibly by Up-regulating Expression of Insulin Receptor and Insulin Receptor Substrate 1 Proteins in Endometrium in Rats with PCOS].

    Science.gov (United States)

    Lai, Mao-Hua; Ma, Hong-Xia; Song, Xing-Hua

    2016-10-25

    To observe the effect of electroacupuncture (EA) intervention combined with clomiphene critate (CC) on the blastocyst implantation and pregnancy rate and expression of insulin receptor (INSR) and insulin receptor substrate 1 (IRS 1) proteins in the endometrium in rats with polycystic ovary syndrome (PCOS), so as to reveal its mechanisms underlying improvement of PCOS. One hundred and twenty-five female SD rats were randomly divided into normal control, PCOS model, medication (CC), EA and EA+CC groups ( n =25 in each group, 15 for checking blastocyst implantation, and 10 for Western blot). The PCOS model was established by subcutaneous injection of Dehydroepiandrosterone (DHEA) and fed with high-fat diet. Rats of the normal control group were treated by subcutaneous injection of sesame oil and fed with the normal forage. EA stimulation was applied to "Zhongwan" (CV 12), "Guanyuan" (CV 4) and bilateral "Tianshu" (ST 25) for 30 min, 3 times a week, 5 weeks altogether. Rats of the CC and EA+CC groups were fed with CC (100 mg·kg -1 ·d -1 ) for 2 days after regular restriction (30 min, 3 times a week, 5 weeks altogether). The pregnancy was determined by vaginal smear tests and the number of blastocyst implantation determined by examination of the uterus after execution. The expression of INSR and IRS 1 proteins in the endometrium was detected by Western blot. The pregnancy rate and the number of blastocyst implantation were significantly lower in the model group than in the normal control group ( P 0.05). The relative expression levels of both INSR and IRS 1 proteins were markedly lower in the model group than in the normal control group ( P 0.05). EA intervention can improve pregnancy rate and the number of blastocyst implantation in PCOS rats, which may be related to its effects in up-regulating the expression of INSR and IRS 1 proteins in the endometrium.

  9. Human chorionic gonadotropin produced by the invasive trophoblast but not the villous trophoblast promotes cell invasion and is down-regulated by peroxisome proliferator-activated receptor-gamma.

    Science.gov (United States)

    Handschuh, Karen; Guibourdenche, Jean; Tsatsaris, Vassilis; Guesnon, Mickaël; Laurendeau, Ingrid; Evain-Brion, Danièle; Fournier, Thierry

    2007-10-01

    A critical step in the establishment of human pregnancy is the invasion of the uterus wall by extravillous cytotrophoblasts (EVCTs) during the first trimester. It is well established that human chorionic gonadotropin hormone (hCG) is secreted by the endocrine syncytiotrophoblast (ST) into the maternal compartment. We recently reported that invasive EVCTs also produce hCG, suggesting an autocrine role in the modulation of trophoblast invasion. Here we analyzed the role of hCG secreted in vitro by primary cultures of invasive EVCT and noninvasive ST. We first demonstrated that LH/CG receptor was present in EVCTs in situ and in vitro as well as in an EVCT cell line (HIPEC65). We next showed that hCG secreted by EVCTs stimulated progesterone secretion by MA10 cells in a concentration-dependent manner. Incubation of HIPEC65 with EVCT supernatants induced a 10-fold increase in cell invasion, whereas ST supernatants had no effect. This stimulating effect was strongly decreased when hCG was depleted from EVCT supernatants containing a large amount of the hyperglycosylated form of hCG, which is almost undetectable in ST supernatants. Finally, we investigated the regulation of hCG expression by peroxisome proliferator-activated receptor (PPAR)-gamma, a nuclear receptor shown to inhibit trophoblast invasion. Activation of PPARgamma decreased alpha- and beta-subunit transcript levels and total hCG secretion in primary EVCTs. Our results offer the first evidence that hCG secreted by the invasive trophoblast, likely the hyperglycosylated form of hCG, but not by the syncytiotrophoblast, promotes trophoblast invasion and may be a PPARgamma target gene in trophoblast invasion process.

  10. Mitogen-activated protein kinase signaling pathways promote low-density lipoprotein receptor-related protein 1-mediated internalization of beta-amyloid protein in primary cortical neurons.

    Science.gov (United States)

    Yang, Wei-Na; Ma, Kai-Ge; Qian, Yi-Hua; Zhang, Jian-Shui; Feng, Gai-Feng; Shi, Li-Li; Zhang, Zhi-Chao; Liu, Zhao-Hui

    2015-07-01

    Mounting evidence suggests that the pathological hallmarks of Alzheimer's disease (AD) are caused by the intraneuronal accumulation of beta-amyloid protein (Aβ). Reuptake of extracellular Aβ is believed to contribute significantly to the intraneuronal Aβ pool in the early stages of AD. Published reports have claimed that the low-density lipoprotein receptor-related protein 1 (LRP1) mediates Aβ1-42 uptake and lysosomal trafficking in GT1-7 neuronal cells and mouse embryonic fibroblast non-neuronal cells. However, there is no direct evidence supporting the role of LRP1 in Aβ internalization in primary neurons. Our recent study indicated that p38 MAPK and ERK1/2 signaling pathways are involved in regulating α7 nicotinic acetylcholine receptor (α7nAChR)-mediated Aβ1-42 uptake in SH-SY5Y cells. This study was designed to explore the regulation of MAPK signaling pathways on LRP1-mediated Aβ internalization in neurons. We found that extracellular Aβ1-42 oligomers could be internalized into endosomes/lysosomes and mitochondria in cortical neurons. Aβ1-42 and LRP1 were also found co-localized in neurons during Aβ1-42 internalization, and they could form Aβ1-42-LRP1 complex. Knockdown of LRP1 expression significantly decreased neuronal Aβ1-42 internalization. Finally, we identified that p38 MAPK and ERK1/2 signaling pathways regulated the internalization of Aβ1-42 via LRP1. Therefore, these results demonstrated that LRP1, p38 MAPK and ERK1/2 mediated the internalization of Aβ1-42 in neurons and provided evidence that blockade of LRP1 or inhibitions of MAPK signaling pathways might be a potential approach to lowering brain Aβ levels and served a potential therapeutic target for AD. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. GPR30, the non-classical membrane G protein related estrogen receptor, is overexpressed in human seminoma and promotes seminoma cell proliferation.

    Directory of Open Access Journals (Sweden)

    Nicolas Chevalier

    Full Text Available BACKGROUND: Testicular germ cell tumours are the most frequent cancer of young men with an increasing incidence all over the world. Pathogenesis and reasons of this increase remain unknown but epidemiological and clinical data have suggested that fetal exposure to environmental endocrine disruptors (EEDs with estrogenic effects, could participate to testicular germ cell carcinogenesis. However, these EEDs (like bisphenol A are often weak ligands for classical nuclear estrogen receptors. Several research groups recently showed that the non classical membrane G-protein coupled estrogen receptor (GPER/GPR30 mediates the effects of estrogens and several xenoestrogens through rapid non genomic activation of signal transduction pathways in various human estrogen dependent cancer cells (breast, ovary, endometrium. The aim of this study was to demonstrate that GPER was overexpressed in testicular tumours and was able to trigger JKT-1 seminoma cell proliferation. RESULTS: We report here for the first time a complete morphological and functional characterization of GPER in normal and malignant human testicular germ cells. In normal adult human testes, GPER was expressed by somatic (Sertoli cells and germ cells (spermatogonia and spermatocytes. GPER was exclusively overexpressed in seminomas, the most frequent testicular germ cell cancer, localized at the cell membrane and triggered a proliferative effect on JKT-1 cells in vitro, which was completely abolished by G15 (a GPER selective antagonist and by siRNA invalidation. CONCLUSION: These results demonstrate that GPER is expressed by human normal adult testicular germ cells, specifically overexpressed in seminoma tumours and able to trigger seminoma cell proliferation in vitro. It should therefore be considered rather than classical ERs when xeno-estrogens or other endocrine disruptors are assessed in testicular germ cell cancers. It may also represent a prognosis marker and/or a therapeutic target for

  12. GPR30, the Non-Classical Membrane G Protein Related Estrogen Receptor, Is Overexpressed in Human Seminoma and Promotes Seminoma Cell Proliferation

    Science.gov (United States)

    Chevalier, Nicolas; Vega, Aurélie; Bouskine, Adil; Siddeek, Bénazir; Michiels, Jean-François; Chevallier, Daniel; Fénichel, Patrick

    2012-01-01

    Background Testicular germ cell tumours are the most frequent cancer of young men with an increasing incidence all over the world. Pathogenesis and reasons of this increase remain unknown but epidemiological and clinical data have suggested that fetal exposure to environmental endocrine disruptors (EEDs) with estrogenic effects, could participate to testicular germ cell carcinogenesis. However, these EEDs (like bisphenol A) are often weak ligands for classical nuclear estrogen receptors. Several research groups recently showed that the non classical membrane G-protein coupled estrogen receptor (GPER/GPR30) mediates the effects of estrogens and several xenoestrogens through rapid non genomic activation of signal transduction pathways in various human estrogen dependent cancer cells (breast, ovary, endometrium). The aim of this study was to demonstrate that GPER was overexpressed in testicular tumours and was able to trigger JKT-1 seminoma cell proliferation. Results We report here for the first time a complete morphological and functional characterization of GPER in normal and malignant human testicular germ cells. In normal adult human testes, GPER was expressed by somatic (Sertoli cells) and germ cells (spermatogonia and spermatocytes). GPER was exclusively overexpressed in seminomas, the most frequent testicular germ cell cancer, localized at the cell membrane and triggered a proliferative effect on JKT-1 cells in vitro, which was completely abolished by G15 (a GPER selective antagonist) and by siRNA invalidation. Conclusion These results demonstrate that GPER is expressed by human normal adult testicular germ cells, specifically overexpressed in seminoma tumours and able to trigger seminoma cell proliferation in vitro. It should therefore be considered rather than classical ERs when xeno-estrogens or other endocrine disruptors are assessed in testicular germ cell cancers. It may also represent a prognosis marker and/or a therapeutic target for seminomas. PMID

  13. A kainate receptor subunit promotes the recycling of the neuron-specific K+-Cl-co-transporter KCC2 in hippocampal neurons.

    Science.gov (United States)

    Pressey, Jessica C; Mahadevan, Vivek; Khademullah, C Sahara; Dargaei, Zahra; Chevrier, Jonah; Ye, Wenqing; Huang, Michelle; Chauhan, Alamjeet K; Meas, Steven J; Uvarov, Pavel; Airaksinen, Matti S; Woodin, Melanie A

    2017-04-14

    Synaptic inhibition depends on a transmembrane gradient of chloride, which is set by the neuron-specific K + -Cl - co-transporter KCC2. Reduced KCC2 levels in the neuronal membrane contribute to the generation of epilepsy, neuropathic pain, and autism spectrum disorders; thus, it is important to characterize the mechanisms regulating KCC2 expression. In the present study, we determined the role of KCC2-protein interactions in regulating total and surface membrane KCC2 expression. Using quantitative immunofluorescence in cultured mouse hippocampal neurons, we discovered that the kainate receptor subunit GluK2 and the auxiliary subunit Neto2 significantly increase the total KCC2 abundance in neurons but that GluK2 exclusively increases the abundance of KCC2 in the surface membrane. Using a live cell imaging assay, we further determined that KCC2 recycling primarily occurs within 1-2 h and that GluK2 produces an ∼40% increase in the amount of KCC2 recycled to the membrane during this time period. This GluK2-mediated increase in surface recycling translated to a significant increase in KCC2 expression in the surface membrane. Moreover, we found that KCC2 recycling is enhanced by protein kinase C-mediated phosphorylation of the GluK2 C-terminal residues Ser-846 and Ser-868. Lastly, using gramicidin-perforated patch clamp recordings, we found that the GluK2-mediated increase in KCC2 recycling to the surface membrane translates to a hyperpolarization of the reversal potential for GABA (E GABA ). In conclusion, our results have revealed a mechanism by which kainate receptors regulate KCC2 expression in the hippocampus. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  14. Conditional abrogation of transforming growth factor-β receptor 1 in PTEN-inactivated endometrium promotes endometrial cancer progression in mice.

    Science.gov (United States)

    Gao, Yang; Lin, Pengfei; Lydon, John P; Li, Qinglei

    2017-09-01

    Although a putative role for transforming growth factor-β (TGFB) signalling in the pathogenesis of human endometrial cancer has long been proposed, the precise function of TGFB signalling in the development and progression of endometrial cancer remains elusive. Depletion of phosphatase and tensin homologue (PTEN) in the mouse uterus causes endometrial cancer. To identify the potential role of TGFB signalling in endometrial cancer, we simultaneously deleted TGFB receptor 1 (Tgfbr1) and Pten in the mouse uterus by using Cre-recombinase driven by the progesterone receptor (termed Pten d/d ;Tgfbr1 d/d ). We found that Pten d/d ;Tgfbr1 d/d mice developed severe endometrial lesions that progressed more rapidly than those resulting from conditional deletion of Pten alone, suggesting that TGFB signalling synergizes with PTEN to suppress endometrial cancer progression. Remarkably, Pten d/d ;Tgfbr1 d/d mice developed distant pulmonary metastases, leading to a significantly reduced lifespan. The development of metastasis and accelerated tumour progression in Pten d/d ;Tgfbr1 d/d mice are associated with increased production of proinflammatory chemokines, enhanced cancer cell motility, as shown by myometrial invasion and disruption, and an altered tumour microenvironment characterized by recruitment of tumour-associated macrophages. Thus, conditional deletion of Tgfbr1 in PTEN-inactivated endometrium leads to a disease that recapitulates invasive and lethal human endometrial cancer. This mouse model may be valuable for preclinical testing of new cancer therapies, particularly those targeting metastasis, one of the hallmarks of cancer and a major cause of death in endometrial cancer patients. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd. Copyright © 2017 Pathological Society of Great Britain and Ireland. Published by John Wiley & Sons, Ltd.

  15. Heteromultivalent targeting of integrin αvβ3 and neuropilin 1 promotes cell survival via the activation of the IGF-1/insulin receptors.

    Science.gov (United States)

    Jia, Tao; Choi, Jungyoon; Ciccione, Jéremy; Henry, Maxime; Mehdi, Ahmad; Martinez, Jean; Eymin, Béatrice; Subra, Gilles; Coll, Jean-Luc

    2018-02-01

    Angiogenesis strongly depends on the activation of integrins, especially integrin α v β 3 , and of neuropilin-1 (NRP-1), a co-receptor of VEGFR2. Dual-targeted molecules that simultaneously block both of them are expected have increased anti-angiogenic and antitumor activity. Toward this goal, we generated bifunctional 40 nm-sized silica nanoparticles (NPs) coated with controlled amounts of cRGD and ATWLPPR peptides and studied their affinity, selectivity and biological activity in HUVECs. Sub-nanomolar concentrations of NPs grafted either with ATWLPPR alone or in combination with cRGD exhibit potent and specific antagonist activity against VEGFR2/AKT signaling. However, a 1 nM concentration of the cRGD/ATWLPPR-heteromultivalent particles (RGD/ATW-NPs) also blocks the phosphorylation of VEGFR2 while co-inducing an unexpected long-lasting activation of AKT via IGF-1R/IR-AKT/GSK3β/eNOS signaling that stimulates cell survival and abrogates the intrinsic toxicity of silica-NPs to serum-starved HUVECs. We also showed that their repeated intravenous administration was associated with the proliferation of human U87MG tumor cells engrafted in nude mice and a dilatation of the tumor blood vessels. We present biochemical evidence for the complex cross-talk generated by the binding of the heteromultivalent NPs with α v β 3 -integrin and with NRP1. In particular, we show for the first time that such heteromultivalent NPs can trans-activate IGF-1/insulin receptors and exert dose-dependent pro-survival activity. This study demonstrates the difficulties in designing targeted silica-based NPs for antiangiogenic therapies and the possible risks posed by undesirable side effects. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. The substance P/NK-1 receptor system: NK-1 receptor antagonists ...

    Indian Academy of Sciences (India)

    The substance P (SP)/neurokinin (NK)-1 receptor system plays an important role in cancer. SP promotes the proliferation of tumour cells, angiogenesis and the migration of tumour cells. We review the involvement of SP, the NK-1 receptor and NK-1 receptor antagonists in cancer. Tumour cells overexpress NK-1 receptors, ...

  17. The MAM (meprin/A5-protein/PTPmu) domain is a homophilic binding site promoting the lateral dimerization of receptor-like protein-tyrosine phosphatase mu.

    Science.gov (United States)

    Cismasiu, Valeriu B; Denes, Stefan A; Reiländer, Helmut; Michel, Hartmut; Szedlacsek, Stefan E

    2004-06-25

    The MAM (meprin/A5-protein/PTPmu) domain is present in numerous proteins with diverse functions. PTPmu belongs to the MAM-containing subclass of protein-tyrosine phosphatases (PTP) able to promote cell-to-cell adhesion. Here we provide experimental evidence that the MAM domain is a homophilic binding site of PTPmu. We demonstrate that the MAM domain forms oligomers in solution and binds to the PTPmu ectodomain at the cell surface. The presence of two disulfide bridges in the MAM molecule was evidenced and their integrity was found to be essential for MAM homophilic interaction. Our data also indicate that PTPmu ectodomain forms oligomers and mediates the cellular adhesion, even in the absence of MAM domain homophilic binding. Reciprocally, MAM is able to interact homophilically in the absence of ectodomain trans binding. The MAM domain therefore contains independent cis and trans interaction sites and we predict that its main role is to promote lateral dimerization of PTPmu at the cell surface. This finding contributes to the understanding of the signal transduction mechanism in MAM-containing PTPs.

  18. Cell- and stage-specific chromatin structure across the Complement receptor 2 (CR2/CD21) promoter coincide with CBF1 and C/EBP-beta binding in B cells.

    Science.gov (United States)

    Cruickshank, Mark N; Fenwick, Emily; Karimi, Mahdad; Abraham, Lawrence J; Ulgiati, Daniela

    2009-08-01

    Stringent developmental transcription requires multiple transcription factor (TF) binding sites, cell-specific expression of signaling molecules, TFs and co-regulators and appropriate chromatin structure. During B-lymphopoiesis, human Complement receptor 2 (CR2/CD21) is detected on immature and mature B cells but not on B cell precursors and plasma cells. We examined cell- and stage-specific human CR2 gene regulation using cell lines modeling B-lymphopoiesis. Chromatin accessibility assays revealed a region between -409 and -262 with enhanced accessibility in mature B cells and pre-B cells, compared to either non-lymphoid or plasma cell-types, however, accessibility near the transcription start site (TSS) was elevated only in CR2-expressing B cells. A correlation between histone acetylation and CR2 expression was observed, while histone H3K4 dimethylation was enriched near the TSS in both CR2-expressing B cells and non-expressing pre-B cells. Candidate sites within the CR2 promoter were identified which could regulate chromatin, including a matrix attachment region associated with CDP, SATB1/BRIGHT and CEBP-beta sites as well as two CBF1 sites. ChIP assays verified that both CBF1 and C/EBP-beta bind the CR2 promoter in B cells raising the possibility that these factors facilitate or respond to alterations in chromatin structure to control the timing and/or level of CR2 transcription.

  19. New role for granulocyte colony-stimulating factor-induced extracellular signal-regulated kinase 1/2 in histone modification and retinoic acid receptor α recruitment to gene promoters: relevance to acute promyelocytic leukemia cell differentiation.

    Science.gov (United States)

    Cassinat, B; Zassadowski, F; Ferry, C; Llopis, L; Bruck, N; Lainey, E; Duong, V; Cras, A; Despouy, G; Chourbagi, O; Beinse, G; Fenaux, P; Rochette Egly, C; Chomienne, C

    2011-04-01

    The induction of the granulocytic differentiation of leukemic cells by all-trans retinoic acid (RA) has been a major breakthrough in terms of survival for acute promyelocytic leukemia (APL) patients. Here we highlight the synergism and the underlying novel mechanism between RA and the granulocyte colony-stimulating factor (G-CSF) to restore differentiation of RA-refractory APL blasts. First, we show that in RA-refractory APL cells (UF-1 cell line), PML-RA receptor alpha (RARα) is not released from target promoters in response to RA, resulting in the maintenance of chromatin repression. Consequently, RARα cannot be recruited, and the RA target genes are not activated. We then deciphered how the combination of G-CSF and RA successfully restored the activation of RA target genes to levels achieved in RA-sensitive APL cells. We demonstrate that G-CSF restores RARα recruitment to target gene promoters through the activation of the extracellular signal-regulated kinase (ERK)/mitogen-activated protein kinase (MAPK) pathway and the subsequent derepression of chromatin. Thus, combinatorial activation of cytokines and RARs potentiates transcriptional activity through epigenetic modifications induced by specific signaling pathways.

  20. Protease-activated receptor-2 promotes kidney tubular epithelial inflammation by inhibiting autophagy via the PI3K/Akt/mTOR signalling pathway.

    Science.gov (United States)

    Du, Chunyang; Zhang, Tao; Xiao, Xia; Shi, Yonghong; Duan, Huijun; Ren, Yunzhuo

    2017-08-02

    Protease-activated receptor-2 (PAR2), which belongs to a specific class of the G-protein-coupled receptors, is central to several inflammation processes. However, the precise molecular mechanism involved remains undefined. Autophagy has been previously shown to affect inflammation. In the present study, we examine the effect of PAR2 on kidney tubular epithelial autophagy and on autophagy-related inflammation and reveal the underlying mechanism involved. Autophagic activity and levels of autophagic marker LC3 were examined in human kidney tubular epithelial cells with PAR2 knockdown or overexpression. We administered the mammalian target of rapamycin (mTOR) inhibitor (rapamycin) or activator (MHY1485) to investigate the function of the phosphoinositide 3-kinase (PI3K)/Akt/mTOR pathway. We also used transforming growth factor-β1 (TGF-β1)-induced HK-2 cell inflammation models to investigate the role of PAR2-associated autophagy in kidney tubular epithelial inflammation. PAR2 antagonist and rapamycin were administered to mice after unilateral ureteral obstruction to detect the correlations between PAR2, autophagy, and inflammation. Our results show that PAR2 overexpression in HK-2 cells led to a greater reduction in autophagy via the PI3K/Akt/mTOR pathway activation and induces autophagy-related inflammation. Meanwhile, a knockdown of PAR2 via PAR2 RNAi transfection greatly increased autophagy and alleviated autophagy-associated inflammation. In unilateral ureteral obstruction (UUO) kidneys, PAR2 antagonist treatment greatly attenuated renal inflammation and interstitial injury by enhancing autophagy. Moreover, inhibition of mTOR, rapa, markedly increased autophagy and inhibited the UUO-induced inflammation. We conclude that PAR2 induces kidney tubular epithelial inflammation by inhibiting autophagy via the PI3K/Akt/mTOR signalling pathway. Our results are suggestive that PAR2 inhibition may play a role in the treatment of diseases with increased inflammatory

  1. Low-Density Lipoprotein Receptor-Related Protein-1 (LRP1) C4408R Mutant Promotes Amyloid Precursor Protein (APP) α-Cleavage in Vitro.

    Science.gov (United States)

    Hou, Huayan; Habib, Ahsan; Zi, Dan; Tian, Kathy; Tian, Jun; Giunta, Brian; Sawmiller, Darrell; Tan, Jun

    2017-09-01

    Previous studies have demonstrated that the low-density lipoprotein receptor-related protein-1 (LRP1) plays conflicting roles in Alzheimer's disease (AD) pathogenesis, clearing β-amyloid (Aβ) from the brain while also enhancing APP endocytosis and resultant amyloidogenic processing. We have recently discovered that co-expression of mutant LRP1 C-terminal domain (LRP1-CT C4408R) with Swedish mutant amyloid precursor protein (APPswe) in Chinese hamster ovary (CHO) cells decreases Aβ production, while also increasing sAPPα and APP α-C-terminal fragment (α-CTF), compared with CHO cells expressing APPswe alone. Surprisingly, the location of this mutation on LRP1 corresponded with the α-secretase cleavage site of APP. Further experimentation confirmed that in CHO cells expressing APPswe or wild-type APP (APPwt), co-expression of LRP1-CT C4408R decreases Aβ and increases sAPPα and α-CTF compared with co-expression of wild-type LRP1-CT. In addition, LRP1-CT C4408R enhanced the unglycosylated form of LRP1-CT and reduced APP endocytosis as determined by flow cytometry. This finding identifies a point mutation in LRP1 which slows LRP1-CT-mediated APP endocytosis and amyloidogenic processing, while enhancing APP α-secretase cleavage, thus demonstrating a potential novel target for slowing AD pathogenesis.

  2. Nicotine promotes cell proliferation via α7-nicotinic acetylcholine receptor and catecholamine-synthesizing enzymes-mediated pathway in human colon adenocarcinoma HT-29 cells

    International Nuclear Information System (INIS)

    Wong, Helen Pui Shan; Yu Le; Lam, Emily Kai Yee; Tai, Emily Kin Ki; Wu, William Ka Kei; Cho, Chi Hin

    2007-01-01

    Cigarette smoking has been implicated in colon cancer. Nicotine is a major alkaloid in cigarette smoke. In the present study, we showed that nicotine stimulated HT-29 cell proliferation and adrenaline production in a dose-dependent manner. The stimulatory action of nicotine was reversed by atenolol and ICI 118,551, a β 1 - and β 2 -selective antagonist, respectively, suggesting the role of β-adrenoceptors in mediating the action. Nicotine also significantly upregulated the expression of the catecholamine-synthesizing enzymes [tyrosine hydroxylase (TH), dopamine-β-hydroxylase (DβH) and phenylethanolamine N-methyltransferase]. Inhibitor of TH, a rate-limiting enzyme in the catecholamine-biosynthesis pathway, reduced the actions of nicotine on cell proliferation and adrenaline production. Expression of α7-nicotinic acetylcholine receptor (α7-nAChR) was demonstrated in HT-29 cells. Methyllycaconitine, an α7-nAChR antagonist, reversed the stimulatory actions of nicotine on cell proliferation, TH and DβH expression as well as adrenaline production. Taken together, through the action on α7-nAChR nicotine stimulates HT-29 cell proliferation via the upregulation of the catecholamine-synthesis pathway and ultimately adrenaline production and β-adrenergic activation. These data reveal the contributory role α7-nAChR and β-adrenoceptors in the tumorigenesis of colon cancer cells and partly elucidate the carcinogenic action of cigarette smoke on colon cancer

  3. Spinal μ-opioid receptor-sensitive lower limb muscle afferents determine corticospinal responsiveness and promote central fatigue in upper limb muscle.

    Science.gov (United States)

    Sidhu, Simranjit K; Weavil, Joshua C; Venturelli, Massimo; Garten, Ryan S; Rossman, Matthew J; Richardson, Russell S; Gmelch, Benjamin S; Morgan, David E; Amann, Markus

    2014-11-15

    We investigated the influence of group III/IV lower limb muscle afferents on the development of supraspinal fatigue and the responsiveness of corticospinal projections to an arm muscle. Eight males performed constant-load leg cycling exercise (80% peak power output) for 30 s (non-fatiguing) and to exhaustion (∼9 min; fatiguing) both under control conditions and with lumbar intrathecal fentanyl impairing feedback from μ-opioid receptor-sensitive lower limb muscle afferents. Voluntary activation (VA) of elbow flexors was assessed via transcranial magnetic stimulation (TMS) during maximum voluntary contraction (MVC) and corticospinal responsiveness was monitored via TMS-evoked potentials (MEPs) during a 25% MVC. Accompanied by a significant 5 ± 1% reduction in VA from pre- to post-exercise, elbow flexor MVC progressively decreased during the fatiguing trial (P muscle afferents, MVC and VA remained unchanged during fatiguing exercise (P > 0.3). MEPs decreased by 36 ± 6% (P lower corticospinal responsiveness during this short bout (P muscle fatigue, group III/IV-mediated leg muscle afferents facilitate responsiveness of the motor pathway to upper limb flexor muscles. By contrast, in the presence of cycling-induced leg fatigue, group III/IV locomotor muscle afferents facilitate supraspinal fatigue in remote muscle not involved in the exercise and disfacilitate, or inhibit, the responsiveness of corticospinal projections to upper limb muscles.

  4. Proinflammatory Stimulation of Toll-Like Receptor 9 with High Dose CpG ODN 1826 Impairs Endothelial Regeneration and Promotes Atherosclerosis in Mice.

    Directory of Open Access Journals (Sweden)

    Alexander O Krogmann

    Full Text Available Toll-like receptors (TLR of the innate immune system have been closely linked with the development of atherosclerotic lesions. TLR9 is activated by unmethylated CpG motifs within ssDNA, but also by CpG motifs in nucleic acids released during vascular apoptosis and necrosis. The role of TLR9 in vascular disease remains controversial and we sought to investigate the effects of a proinflammatory TLR9 stimulation in mice.TLR9-stimulation with high dose CpG ODN at concentrations between 6.25 nM to 30 nM induced a significant proinflammatory cytokine response in mice. This was associated with impaired reendothelialization upon acute denudation of the carotid and increased numbers of circulating endothelial microparticles, as a marker for amplified endothelial damage. Chronic TLR9 agonism in apolipoprotein E-deficient (ApoE-/- mice fed a cholesterol-rich diet increased aortic production of reactive oxygen species, the number of circulating endothelial microparticles, circulating sca-1/flk-1 positive cells, and most importantly augmented atherosclerotic plaque formation when compared to vehicle treated animals. Importantly, high concentrations of CpG ODN are required for these proatherogenic effects.Systemic stimulation of TLR9 with high dose CpG ODN impaired reendothelialization upon acute vascular injury and increased atherosclerotic plaque development in ApoE-/- mice. Further studies are necessary to fully decipher the contradictory finding of TLR9 agonism in vascular biology.

  5. Chronic obstructive pulmonary disease and asthma-associated Proteobacteria, but not commensal Prevotella spp., promote Toll-like receptor 2-independent lung inflammation and pathology.

    Science.gov (United States)

    Larsen, Jeppe M; Musavian, Hanieh S; Butt, Tariq M; Ingvorsen, Camilla; Thysen, Anna H; Brix, Susanne

    2015-02-01

    Recent studies of healthy human airways have revealed colonization by a distinct commensal bacterial microbiota containing Gram-negative Prevotella spp. However, the immunological properties of these bacteria in the respiratory system remain unknown. Here we compare the innate respiratory immune response to three Gram-negative commensal Prevotella strains (Prevotella melaninogenica, Prevotella nanceiensis and Prevotella salivae) and three Gram-negative pathogenic Proteobacteria known to colonize lungs of patients with chronic obstructive pulmonary disease (COPD) and asthma (Haemophilus influenzae B, non-typeable Haemophilus influenzae and Moraxella catarrhalis). The commensal Prevotella spp. and pathogenic Proteobacteria were found to exhibit intrinsic differences in innate inflammatory capacities on murine lung cells in vitro. In vivo in mice, non-typeable H. influenzae induced severe Toll-like receptor 2 (TLR2)-independent COPD-like inflammation characterized by predominant airway neutrophilia, expression of a neutrophilic cytokine/chemokine profile in lung tissue, and lung immunopathology. In comparison, P. nanceiensis induced a diminished neutrophilic airway inflammation and no detectable lung pathology. Interestingly, the inflammatory airway response to the Gram-negative bacteria P. nanceiensis was completely TLR2-dependent. These findings demonstrate weak inflammatory properties of Gram-negative airway commensal Prevotella spp. that may make colonization by these bacteria tolerable by the respiratory immune system. © 2014 John Wiley & Sons Ltd.

  6. Pannexin channels mediate the acquisition of myogenic commitment in C2C12 reserve cells promoted by P2 receptor activation

    Science.gov (United States)

    Riquelme, Manuel A.; Cea, Luis A.; Vega, José L.; Puebla, Carlos; Vargas, Aníbal A.; Shoji, Kenji F.; Subiabre, Mario; Sáez, Juan C.

    2015-01-01

    The acquisition of myoblast commitment to the myogenic linage requires rises in intracellular free Ca2+ concentration ([Ca2+]i). Putative cell membrane pathways involved in these [Ca2+]i increments are P2 receptors (P2Rs) as well as connexin (Cx) and/or pannexin (Panx) hemichannels and channels (Cx HChs and Panx Chs), respectively, which are known to permeate Ca2+. Reserve cells (RCs) are uncommitted myoblasts obtained from differentiated C2C12 cell cultures, which acquire commitment upon replating. Regarding these cells, we found that extracellular ATP increases the [Ca2+]i via P2Rs. Moreover, ATP increases the plasma membrane permeability to small molecules and a non-selective membrane current, both of which were inhibited by Cx HCh/Panx1Ch blockers. However, RCs exposed to divalent cation-free saline solution, which is known to activate Cx HChs (but not Panx Chs), did not enhance membrane permeability, thus ruling out the possible involvement of Cx HChs. Moreover, ATP-induced membrane permeability was inhibited with blockers of P2Rs that activate Panx Chs. In addition, exogenous ATP induced the expression of myogenic commitment and increased MyoD levels, which was prevented by the inhibition of P2Rs or knockdown of Panx1 Chs. Similarly, increases in MyoD levels induced by ATP released by RCs were inhibited by Panx Ch/Cx HCh blockers. Myogenic commitment acquisition thus requires a feed-forward mechanism mediated by extracellular ATP, P2Rs, and Panx Chs. PMID:26000275

  7. Abnormal Accumulation of Collagen Type I Due to the Loss of Discoidin Domain Receptor 2 (Ddr2 Promotes Testicular Interstitial Dysfunction.

    Directory of Open Access Journals (Sweden)

    Chu-chao Zhu

    Full Text Available Loss of functional allele for discoidin domain receptor 2 (Ddr2 results in impaired Leydig cell response to luteinizing hormone (LH, low testosterone production and arrested spermatogenesis in older male Ddr2slie/slie mice. However, the underlying mechanism responsible for this phenotype remains unknown. Herein, we reported for the first time that the deregulated expression of Ddr2 cognate ligand, namely collagen type I (COL1, may account for the disruption of the testicular steroidogenesis in Ddr2slie/slie mutant testes.Expression of Ddr2 increased gradually along postnatal development, whereas COL1 expression became negligible from adulthood onwards. In Ddr2slie/slie mutant testis, however, in contrast to the undetectable staining of Ddr2, COL1 expression was constantly detected, with the highest values detected during adulthood. In the experimental vasectomy model, Ddr2slie/slie mutant mice exhibited an early androgen deficiency than wild-type mice, along with the accumulation of fibrotic tissue in the interstitium. Functionally, ablation of endogenous Ddr2 resulted in a significant decrease of testosterone (T level in TM3 cells in the presence of higher concentration of COL1 treatment. Conversely, overexpression of Ddr2 could help TM3 cells to maintain a normal testicular steroidogenesis even in the presence of high concentration of COL1. Additionally, attenuated expression of Ddr2 correlates to the deregulated level of serum T levels in human pathological testes.Abnormal accumulation of interstitial COL1 may be responsible for the steroidogenic dysfunction in Ddr2slie/slie mutant testes.

  8. The leukotriene B4-leukotriene B4 receptor axis promotes cisplatin-induced acute kidney injury by modulating neutrophil recruitment.

    Science.gov (United States)

    Deng, Bo; Lin, Yuli; Ma, Shuai; Zheng, Yin; Yang, Xuguang; Li, Bingji; Yu, Wenyan; Xu, Qingqing; Liu, Tingyan; Hao, Chuanming; He, Rui; Ding, Feng

    2017-07-01

    Cisplatin is an effective chemotherapeutic agent and widely used in treatment of various solid organ malignancies, including head and neck, ovarian, and testicular cancers. However, the induction of acute kidney injury (AKI) is one of its main side effects. Leukotriene B 4 receptor 1 (BLT1) mediates the majority of physiological effects of leukotriene B 4 (LTB 4 ), a potent lipid chemoattractant generated at inflammation sites, but the role of the LTB 4 -BLT1 axis in cisplatin-induced AKI remains unknown. Here we found upregulated LTB 4 synthesis and BLT1 expression in the kidney after cisplatin administration. Cisplatin was found to directly upregulate gene expression of leukotriene A 4 hydrolase and stimulate LTB 4 production in renal tubular epithelial cells. Reduced kidney structural/functional damage, inflammation, and apoptosis were observed in BLT1 -/- mice, as well as in wild-type mice treated with the LTA4H inhibitor SC-57461A and the BLT1 antagonist U-75302. Neutrophils were likely the target of this pathway, as BLT1 absence induced a significant decrease in infiltrating neutrophils in the kidney. Adoptive transfer of neutrophils from wild-type mice restored kidney injury in BLT1 -/- mice following cisplatin challenge. Thus, the LTB 4 -BLT1 axis contributes to cisplatin-induced AKI by mediating kidney recruitment of neutrophils, which induce inflammation and apoptosis in the kidney. Hence, the LTB 4 -BLT1 axis could be a potential therapeutic target in cisplatin-induced AKI. Copyright © 2017 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  9. LGR5 receptor promotes cell-cell adhesion in stem cells and colon cancer cells via the IQGAP1-Rac1 pathway.

    Science.gov (United States)

    Carmon, Kendra S; Gong, Xing; Yi, Jing; Wu, Ling; Thomas, Anthony; Moore, Catherine M; Masuho, Ikuo; Timson, David J; Martemyanov, Kirill A; Liu, Qingyun J

    2017-09-08

    Leucine-rich repeat-containing G protein-coupled receptor 5 (LGR5) is a bona fide marker of adult stem cells in several epithelial tissues, most notably in the intestinal crypts, and is highly up-regulated in many colorectal, hepatocellular, and ovarian cancers. LGR5 activation by R-spondin (RSPO) ligands potentiates Wnt/β-catenin signaling in vitro ; however, deletion of LGR5 in stem cells has little or no effect on Wnt/β-catenin signaling or cell proliferation in vivo Remarkably, modulation of LGR5 expression has a major impact on the actin cytoskeletal structure and cell adhesion in the absence of RSPO stimulation, but the molecular mechanism is unclear. Here, we show that LGR5 interacts with IQ motif-containing GTPase-activating protein 1 (IQGAP1), an effector of Rac1/CDC42 GTPases, in the regulation of actin cytoskeleton dynamics and cell-cell adhesion. Specifically, LGR5 decreased levels of IQGAP1 phosphorylation at Ser-1441/1443, leading to increased binding of Rac1 to IQGAP1 and thus higher levels of cortical F-actin and enhanced cell-cell adhesion. LGR5 ablation in colon cancer cells and crypt stem cells resulted in loss of cortical F-actin, reduced cell-cell adhesion, and disrupted localization of adhesion-associated proteins. No evidence of LGR5 coupling to any of the four major subtypes of heterotrimeric G proteins was found. These findings suggest that LGR5 primarily functions via the IQGAP1-Rac1 pathway to strengthen cell-cell adhesion in normal adult crypt stem cells and colon cancer cells. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  10. Von Hippel-Lindau tumor suppressor gene loss in renal cell carcinoma promotes oncogenic epidermal growth factor receptor signaling via Akt-1 and MEK-1.

    Science.gov (United States)

    Lee, S Justin; Lattouf, Jean-Baptiste; Xanthopoulos, Julie; Linehan, W Marston; Bottaro, Donald P; Vasselli, James R

    2008-10-01

    Clear-cell renal cell carcinoma (RCC) is the most prevalent form of kidney cancer and is frequently associated with loss of von Hippel-Lindau (VHL) gene function, resulting in the aberrant transcriptional activation of genes that contribute to tumor growth and metastasis, including transforming growth factor-alpha (TGF-alpha), a ligand of the epidermal growth factor receptor (EGFR) tyrosine kinase. To determine the functional impact of EGFR activation on RCC, we suppressed critical components of this pathway: EGFR, Akt-1, and MEK-1. Stable transfection of RCC cells with plasmids bearing shRNA directed against each of these genes was used to individually suppress their expression. Transfectants were characterized for growth and invasiveness in vitro and tumorigenesis in vivo. RCC cell transfectants displayed significantly reduced growth rate and matrix invasion in vitro and RCC tumor xenograft growth rate in vivo. Analysis of tumor cells that emerged after extended periods in each model showed that significant EGFR suppression was sustained, whereas Akt-1 and MEK-1 knock-down cells had escaped shRNA suppression. EGFR, Akt-1, and MEK-1 are individually critical for RCC cell invasiveness in vitro and tumorigenicity in vivo, and even partial suppression of each can have a significant impact on tumor progression. The emergence of transfectants that had escaped Akt-1 and MEK-1 suppression during tumorigenicity experiments suggests that these effectors may each be more critical than EGFR for RCC tumorigenesis, consistent with results from clinical trials of EGFR inhibitors for RCC, where durable clinical responses have not been seen.

  11. Von Hippel-Lindau Tumor Suppressor Gene Loss in Renal Cell Carcinoma Promotes Oncogenic Epidermal Growth Factor Receptor Signaling via Akt-1 and MEK1

    Science.gov (United States)

    Lee, S. Justin; Lattouf, Jean-Baptiste; Xanthopoulos, Julie; Linehan, W. Marston; Bottaro, Donald P.; Vasselli, James R.

    2008-01-01

    Objectives Clear-cell renal cell carcinoma (RCC) is the most prevalent form of kidney cancer and is frequently associated with loss of von Hippel-Lindau (VHL) gene function, resulting in the aberrant transcriptional activation of genes that contribute to tumor growth and metastasis, including transforming growth factor-α (TGF-α), a ligand of the epidermal growth factor receptor (EGFR) tyrosine kinase. To determine the functional impact of EGFR activation on RCC, we suppressed critical components of this pathway: EGFR, Akt-1, and MEK-1. Methods Stable transfection of RCC cells with plasmids bearing shRNA directed against each of these genes was used to individually suppress their expression. Transfectants were characterized for growth and invasiveness in vitro and tumorigenesis in vivo. Results RCC cell transfectants displayed significantly reduced growth rate and matrix invasion in vitro and RCC tumor xenograft growth rate in vivo. Analysis of tumor cells that emerged after extended periods in each model showed that significant EGFR suppression was sustained, whereas Akt-1 and MEK-1 knockdown cells had escaped shRNA suppression. Conclusions EGFR, Akt-1, and MEK-1 are individually critical for RCC cell invasiveness in vitro and tumorigenicity in vivo, and even partial suppression of each can have a significant impact on tumor progression. The emergence of transfectants that had escaped Akt-1 and MEK-1 suppression during tumorigenicity experiments suggests that these effectors may each be more critical than EGFR for RCC tumorigenesis, consistent with results from clinical trials of EGFR inhibitors for RCC, where durable clinical responses have not been seen. PMID:18243508

  12. The type I insulin-like growth factor receptor regulates cancer metastasis independently of primary tumor growth by promoting invasion and survival

    Science.gov (United States)

    Sachdev, Deepali; Zhang, Xihong; Matise, Ilze; Gaillard-Kelly, Martine; Yee, Douglas

    2009-01-01

    The type I insulin-like growth factor receptor (IGF1R) regulates multiple aspects of malignancy and is the target of several drugs currently in clinical trials. While IGF1R’s role in proliferation and survival is well-studied, the regulation of metastasis by IGF1R is not as clearly delineated. Previous work showed that disruption of IGF1R signaling via overexpression of a dominant negative IGF1R inhibited metastasis. To establish a clinically applicable approach to inhibition of metastasis by targeting IGF1R, the effect of an inhibitory antibody against IGF1R, EM164 and its humanized version, AVE1642 on metastasis of cancer cells was examined. EM164 and AVE1642 did not affect primary tumor growth of MDA-435A/LCC6 cells but inhibited metastasis of these cells. Consistent with this inhibition in the formation of metastatic nodules, disruption of IGF1R also resulted in a decreased number of circulating tumor cells in blood of tumor-bearing mice. Disruption of IGF1R with a dominant negative construct or antibody inhibited invasion across Matrigel in vitro. When tumor cells were directly injected into the circulation via the lateral tail vein of mice, IGF1R disruption also resulted in significant reduction of pulmonary nodules, suggesting that regulation of invasion is not the only function of IGF1R signaling. Further, disruption of IGF1R rendered cells more susceptible to anoikis. Thus, IGF1R regulated metastasis independently of tumor growth. The multiple phenotypes regulated by IGF1R must be considered during development of this therapeutic strategy as inhibition of metastasis independent of inhibition of tumor growth is not easily assessed in phase II clinical trials. PMID:19838209

  13. Suppression of WIF-1 through promoter hypermethylation causes accelerated proliferation of the aryl hydrocarbon receptor (AHR) overexpressing MCF10AT1 breast cancer cells

    International Nuclear Information System (INIS)

    Wu, Dalei; Wong, Patrick; Li, Wen; Vogel, Christoph F.; Matsumura, Fumio

    2011-01-01

    Highlights: → 5-Aza-2'-deoxycytidine (AZ) causes proliferation suppression and ERα recovery. → AZ down-regulates Wnt/β-catenin pathway mainly by increasing WIF-1 expression. → Both ERα and AhR have some effects on DNA methylation in breast cancer cells. → Artificial overexpression of ERα in ER negative cells increases WIF-1 expression. → WIF-1 promoter hypermethylation is one of the major causes for accelerated proliferation. -- Abstract: The cause for increased cell proliferation in AHR overexpressing breast cancer cells still remains unknown. Here we studied the molecular basis of aggressive cell proliferation of an AHR overexpressing and ERα functionally down-regulated MCF10AT1 cell line, designated as P20E, in comparison to a matched sub-line, P20C with normal AHR expression and ERα function. We found that a 4-day treatment of P20E cells with 5-aza-2'-deoxycytidine (AZ) caused a significant suppression of cell proliferation. Such an effect of AZ was accompanied with the significant recovery of ERα function. Among diagnostic markers of AZ-induced cellular changes we found conspicuous up-regulation of mRNA expression of Wnt inhibitory factor-1 (WIF-1), particularly in P20E. The possibility of AZ-induced demethylation on the promoter of WIF-1 gene was confirmed through methylation specific PCR assay. Such AZ-induced changes in P20E cells were also accompanied with the decrease in the binding of nuclear proteins to the 32 P labeled TRE (TCF response element) and the reduced accumulation of β-catenin protein in the cell nucleus, indicating the importance of Wnt/β-catenin pathway in maintaining the increased cell proliferation in P20E line over P20C line. The importance of WIF-1 in this regard has been validated by transfecting cells with siRNA against WIF-1, which caused an increase in cell proliferation. Moreover, artificial overexpression of ERα in both P20E as well as MDA-MB-231 cells increased the mRNA expression of WIF-1. Together these

  14. Self protection from anti-viral responses--Ro52 promotes degradation of the transcription factor IRF7 downstream of the viral Toll-Like receptors.

    LENUS (Irish Health Repository)

    Higgs, Rowan

    2010-01-01

    Ro52 is a member of the TRIM family of single-protein E3 ligases and is also a target for autoantibody production in systemic lupus erythematosus and Sjögren\\'s syndrome. We previously demonstrated a novel function of Ro52 in the ubiquitination and proteasomal degradation of IRF3 following TLR3\\/4 stimulation. We now present evidence that Ro52 has a similar role in regulating the stability and activity of IRF7. Endogenous immunoprecipitation of Ro52-bound proteins revealed that IRF7 associates with Ro52, an effect which increases following TLR7 and TLR9 stimulation, suggesting that Ro52 interacts with IRF7 post-pathogen recognition. Furthermore, we show that Ro52 ubiquitinates IRF7 in a dose-dependent manner, resulting in a decrease in total IRF7 expression and a subsequent decrease in IFN-alpha production. IRF7 stability was increased in bone marrow-derived macrophages from Ro52-deficient mice stimulated with imiquimod or CpG-B, consistent with a role for Ro52 in the negative regulation of IRF7 signalling. Taken together, these results suggest that Ro52-mediated ubiquitination promotes the degradation of IRF7 following TLR7 and TLR9 stimulation. As Ro52 is known to be IFN-inducible, this system constitutes a negative-feedback loop that acts to protect the host from the prolonged activation of the immune response.

  15. Funiculosin variants and phosphorylated derivatives promote innate immune responses via the Toll-like receptor 4/myeloid differentiation factor-2 complex.

    Science.gov (United States)

    Okamoto, Naoki; Mizote, Keisuke; Honda, Hiroe; Saeki, Akinori; Watanabe, Yasuharu; Yamaguchi-Miyamoto, Tomomi; Fukui, Ryutaro; Tanimura, Natsuko; Motoi, Yuji; Akashi-Takamura, Sachiko; Kato, Tatsuhisa; Fujishita, Shigeto; Kimura, Takahito; Ohto, Umeharu; Shimizu, Toshiyuki; Hirokawa, Takatsugu; Miyake, Kensuke; Fukase, Koichi; Fujimoto, Yukari; Nagai, Yoshinori; Takatsu, Kiyoshi

    2017-09-15

    The Toll-like receptor 4 (TLR4)/myeloid differentiation factor-2 (MD-2) complex is essential for LPS recognition and induces innate immune responses against Gram-negative bacteria. As activation of TLR4/MD-2 is also critical for the induction of adaptive immune responses, TLR4/MD-2 agonists have been developed as vaccine adjuvants, but their efficacy has not yet been ascertained. Here, we demonstrate that a funiculosin (FNC) variant, FNC-RED, and FNC-RED and FNC derivatives are agonists for both murine and human TLR4/MD-2. FNC-RED induced nuclear factor-κB (NF-κB) activation via murine TLR4/MD-2, whereas FNC had no TLR4/MD-2 stimulatory activity. Biacore analysis revealed that FNC-RED binds to murine TLR4/MD-2 but not murine radioprotective 105 (RP105)/myeloid differentiation factor-1 (MD-1), another LPS sensor. FNC-RED induced CD14-independent expressions of pro-inflammatory cytokines and co-stimulatory molecules in murine macrophages and dendritic cells. In contrast, FNC-RED stimulation was reduced in CD14-dependent LPS responses, including dimerization and internalization of TLR4/MD-2 and IFN-β expression. FNC-RED-induced IL-12p40 production from murine dendritic cells was dependent on NF-κB but not MAPK pathway. In addition, fetal bovine serum augmented lipid A-induced NF-κB activation but blocked FNC-RED-mediated responses. Two synthetic phosphate group-containing FNC-RED and FNC derivatives, FNC-RED-P01 and FNC-P01, respectively, activated human TLR4/MD-2, unlike FNC-RED. Finally, computational analysis revealed that this species-specific activation by FNC-RED and FNC-RED-P01 resulted from differences in electrostatic surface potentials between murine and human TLR4/MD-2. We conclude that FNC-RED and its synthetic derivative represent a novel category of murine and human TLR4/MD-2 agonist. © 2017 by The American Society for Biochemistry and Molecular Biology, Inc.

  16. Fibrinogen cleavage products and Toll-like receptor 4 promote the generation of programmed cell death 1 ligand 2-positive dendritic cells in allergic asthma.

    Science.gov (United States)

    Cho, Minkyoung; Lee, Jeong-Eun; Lim, Hoyong; Shin, Hyun-Woo; Khalmuratova, Roza; Choi, Garam; Kim, Hyuk Soon; Choi, Wahn Soo; Park, Young-Jun; Shim, Inbo; Kim, Byung-Seok; Kang, Chang-Yuil; Kim, Jae-Ouk; Tanaka, Shinya; Kubo, Masato; Chung, Yeonseok

    2017-10-14

    Inhaled protease allergens preferentially trigger T H 2-mediated inflammation in allergic asthma. The role of dendritic cells (DCs) on induction of T H 2 cell responses in allergic asthma has been well documented; however, the mechanism by which protease allergens induce T H 2-favorable DCs in the airway remains unclear. We sought to determine a subset of DCs responsible for T H 2 cell responses in allergic asthma and the mechanism by which protease allergens induce the DC subset in the airway. Mice were challenged intranasally with protease allergens or fibrinogen cleavage products (FCPs) to induce allergic airway inflammation. DCs isolated from mediastinal lymph nodes were analyzed for surface phenotype and T-cell stimulatory function. Anti-Thy1.2 and Mas-TRECK mice were used to deplete innate lymphoid cells and mast cells, respectively. Adoptive cell transfer, bone marrow DC culture, anti-IL-13, and Toll-like receptor (TLR) 4-deficient mice were used for further mechanistic studies. Protease allergens induced a remarkable accumulation of T H 2-favorable programmed cell death 1 ligand 2 (PD-L2) + DCs in mediastinal lymph nodes, which was significantly abolished in mice depleted of mast cells and, to a lesser extent, innate lymphoid cells. Mechanistically, FCPs generated by protease allergens triggered IL-13 production from wild-type mast cells but not from TLR4-deficient mast cells, which resulted in an increase in the number of PD-L2 + DCs. Intranasal administration of FCPs induced an increase in numbers of PD-L2 + DCs in the airway, which was significantly abolished in TLR4- and mast cell-deficient mice. Injection of IL-13 restored the PD-L2 + DC population in mice lacking mast cells. Our findings unveil the "protease-FCP-TLR4-mast cell-IL-13" axis as a molecular mechanism for generation of T H 2-favorable PD-L2 + DCs in allergic asthma and suggest that targeting the PD-L2 + DC pathway might be effective in suppressing allergic T-cell responses in the airway

  17. Toll-like receptor 3 stimulation promotes Ro52/TRIM21 synthesis and nuclear redistribution in salivary gland epithelial cells, partially via type I interferon pathway

    Science.gov (United States)

    Kyriakidis, N C; Kapsogeorgou, E K; Gourzi, V C; Konsta, O D; Baltatzis, G E; Tzioufas, A G

    2014-01-01

    Up-regulated expression of Ro52/tripartite motif-containing protein 21 (TRIM21), Ro60/TROVE domain family, member 2 (TROVE2) and lupus LA protein/Sjögren's syndrome antigen B (La/SSB) autoantigens has been described in the salivary gland epithelial cells (SGEC) of patients with Sjögren's syndrome (SS). SGECs, the key regulators of autoimmune SS responses, express high levels of surface functional Toll-like receptor (TLR)-3, whereas Ro52/TRIM21 negatively regulates TLR-3-mediated inflammation. Herein, we investigated the effect of TLR-3-signalling on the expression of Ro52/TRIM21, as well as Ro60/TROVE2 and La/SSB autoantigens, by SGECs. The effect of TLR-3 or TLR-4 stimulation on autoantigen expression was evaluated by polyI:C or lipopolysaccharide (LPS) treatment, respectively, of SGEC lines (10 from SS patients, 12 from non-SS controls) or HeLa cells, followed by analysis of mRNA and protein expression. PolyI:C, but not LPS, resulted in a two-step induction of Ro52/TRIM21 mRNA expression by SGECs, a 12-fold increment at 6 h followed by a 2·5-fold increment at 24–48 h, whereas it induced a late two-fold up-regulation of Ro60/TROVE2 and La/SSB mRNAs at 48 h. Although protein expression levels were not affected significantly, the late up-regulation of Ro52/TRIM21 mRNA was accompanied by protein redistribution, from nucleolar-like pattern to multiple coarse dots spanning throughout the nucleus. These late phenomena were mediated significantly by interferon (IFN)-β production, as attested by cognate secretion and specific inhibition experiments and associated with IFN regulatory factor (IRF)3 degradation. TLR-3-signalling had similar effects on SGECs obtained from SS patients and controls, whereas it did not affect the expression of these autoantigens in HeLa cells. TLR-3 signalling regulates the expression of autoantigens by SGECs, implicating innate immunity pathways in their over-expression in inflamed tissues and possibly in their exposure to the immune

  18. Epstein-Barr virus lytic infection promotes activation of Toll-like receptor 8 innate immune response in systemic sclerosis monocytes.

    Science.gov (United States)

    Farina, Antonella; Peruzzi, Giovanna; Lacconi, Valentina; Lenna, Stefania; Quarta, Silvia; Rosato, Edoardo; Vestri, Anna Rita; York, Michael; Dreyfus, David H; Faggioni, Alberto; Morrone, Stefania; Trojanowska, Maria; Farina, G Alessandra

    2017-02-28

    Monocytes/macrophages are activated in several autoimmune diseases, including systemic sclerosis (scleroderma; SSc), with increased expression of interferon (IFN)-regulatory genes and inflammatory cytokines, suggesting dysregulation of the innate immune response in autoimmunity. In this study, we investigated whether the lytic form of Epstein-Barr virus (EBV) infection (infectious EBV) is present in scleroderma monocytes and contributes to their activation in SSc. Monocytes were isolated from peripheral blood mononuclear cells (PBMCs) depleted of the CD19+ cell fraction, using CD14/CD16 negative-depletion. Circulating monocytes from SSc and healthy donors (HDs) were infected with EBV. Gene expression of innate immune mediators were evaluated in EBV-infected monocytes from SSc and HDs. Involvement of Toll-like receptor (TLR)8 in viral-mediated TLR8 response was investigated by comparing the TLR8 expression induced by infectious EBV to the expression stimulated by CL075/TLR8/agonist-ligand in the presence of TLR8 inhibitor in THP-1 cells. Infectious EBV strongly induced TLR8 expression in infected SSc and HD monocytes in vitro. Markers of activated monocytes, such as IFN-regulated genes and chemokines, were upregulated in SSc- and HD-EBV-infected monocytes. Inhibiting TLR8 expression reduced virally induced TLR8 in THP-1 infected cells, demonstrating that innate immune activation by infectious EBV is partially dependent on TLR8. Viral mRNA and proteins were detected in freshly isolated SSc monocytes. Microarray analysis substantiated the evidence of an increased IFN signature and altered level of TLR8 expression in SSc monocytes carrying infectious EBV compared to HD monocytes. This study provides the first evidence of infectious EBV in monocytes from patients with SSc and links EBV to the activation of TLR8 and IFN innate immune response in freshly isolated SSc monocytes. This study provides the first evidence of EBV replication activating the TLR8 molecular pathway

  19. Active Hexose Correlated Compound (AHCC) promotes an intestinal immune response in BALB/c mice and in primary intestinal epithelial cell culture involving toll-like receptors TLR-2 and TLR-4.

    Science.gov (United States)

    Mallet, Jean-François; Graham, Émilie; Ritz, Barry W; Homma, Kohei; Matar, Chantal

    2016-02-01

    Active Hexose Correlated Compound (AHCC(®)) is a cultured mushroom extract that is commercially available and promoted for immune support. Available data suggest that AHCC supplementation affects immune cell populations and immune outcomes, including natural killer cell response to infection. The mechanism by which AHCC exerts its effects is not well understood. The present work aimed to characterize the immunomodulatory activity of AHCC in the gut and to study the effects of AHCC on toll-like receptor (TLR) signaling in intestinal epithelial cells (IECs). BALB/c mice were fed AHCC by gavage. In vivo activities were assessed by immunohistochemistry and cytokine production. The effects of AHCC on ex vivo primary cell culture from IECs were examined after challenge with LPS or E. coli alone or in the presence of anti-TLR-2 and TLR-4 blocking antibodies. Feeding AHCC resulted in increased IgA+ cells in the intestine and increased sIgA, IL-10, and IFN-γ in the intestinal fluid. In IECs, contact with AHCC increased IL-6 production but not to the pro-inflammatory level of positive controls, LPS and E. coli. Blocking TLR-2 and TLR-4 reduced the induction of IL-6 by AHCC, suggesting that these innate receptors are involved in generating the immune response of IECs to AHCC. AHCC may play a role in the orchestration of immune response and the maintenance of immune homeostasis in part by priming the TLR-2 and TLR-4 gate at the intestinal epithelium. Such a response is likely due to the recognition of non-pathogenic food-associated molecular patterns (FAMPs) such as those found associated with other mushroom or yeast-derived compounds.

  20. Helicobacter pylori Hp(2-20) promotes migration and proliferation of gastric epithelial cells by interacting with formyl peptide receptors in vitro and accelerates gastric mucosal healing in vivo.

    Science.gov (United States)

    de Paulis, Amato; Prevete, Nella; Rossi, Francesca W; Rivellese, Felice; Salerno, Fiamma; Delfino, Gabriele; Liccardo, Bianca; Avilla, Elvira; Montuori, Nunzia; Mascolo, Massimo; Staibano, Stefania; Melillo, Rosa Marina; D'Argenio, Giuseppe; Ricci, Vittorio; Romano, Marco; Marone, Gianni

    2009-09-15

    Helicobacter pylori-derived peptide RpL1 aa 2-20 (Hp(2-20)) in addition to its antimicrobial action exerts several immunomodulatory effects in eukaryotic cells by interacting with formyl peptide receptors (FPRs). It has recently been shown that activation of FPRs facilitates intestinal epithelial cell restitution. We investigated whether Hp(2-20) induces healing of injured gastric mucosa and assessed the mechanisms underlying any such effect. We investigated the expression of FPRs in two gastric epithelial cell lines (MKN-28 and AGS) at mRNA and protein level. To determine whether FPRs were functional we performed chemotaxis experiments and proliferation assays and studied the Hp(2-20)-activated downstream signaling pathway. The effect of Hp(2-20) on mucosal healing was evaluated in rats after indomethacin-induced injury. Here we show that: (1) FPRs were expressed in both cell lines; (2) Hp(2-20) stimulated migration and proliferation of gastric epithelial cells; (3) this effect was specifically mediated by formyl peptide receptor-like 1 (FPRL1) and FPRL2 and was associated with activation of FPR-related downstream signaling pathways; (4) Hp(2-20) up-regulated the expression and secretion of vascular endothelial growth factor; and (5) Hp(2-20) accelerated healing of rat gastric mucosa after injury brought about by indomethacin at both the macroscopic and microscopic levels. In conclusion, by interacting with FRPL1 and FPRL2, H. pylori-derived Hp(2-20) induces cell migration and proliferation, as well as the expression of vascular endothelial growth factor, thereby promoting gastric mucosal healing. This study provides further evidence of the complexity of the relationship between H. pylori and human gastric mucosa, and it suggests that a bacterial product may be used to heal gastric mucosal injury.

  1. Early secreted antigen ESAT-6 of Mycobacterium tuberculosis promotes protective T helper 17 cell responses in a toll-like receptor-2-dependent manner.

    Directory of Open Access Journals (Sweden)

    Samit Chatterjee

    2011-11-01

    Full Text Available Despite its relatively poor efficacy, Bacillus Calmette-Guérin (BCG has been used as a tuberculosis (TB vaccine since its development in 1921. BCG induces robust T helper 1 (Th1 immune responses but, for many individuals, this is not sufficient for host resistance against Mycobacterium tuberculosis (M. tb infection. Here we provide evidence that early secreted antigenic target protein 6 (ESAT-6, expressed by the virulent M. tb strain H37Rv but not by BCG, promotes vaccine-enhancing Th17 cell responses. These activities of ESAT-6 were dependent on TLR-2/MyD88 signalling and involved IL-6 and TGF-β production by dendritic cells. Thus, animals that were previously infected with H37Rv or recombinant BCG containing the RD1 region (BCG::RD1 exhibited improved protection upon re-challenge with virulent H37Rv compared with mice previously infected with BCG or RD1-deficient H37Rv (H37RvΔRD1. However, TLR-2 knockout (TLR-2⁻/⁻ animals neither showed Th17 responses nor exhibited improved protection in response to immunization with H37Rv. Furthermore, H37Rv and BCG::RD1 infection had little effect on the expression of the anti-inflammatory microRNA-146a (miR146a in dendritic cells (DCs, whereas BCG and H37RvΔRD1 profoundly induced its expression in DCs. Consistent with these findings, ESAT-6 had no effect on miR146a expression in uninfected DCs, but dramatically inhibited its upregulation in BCG-infected or LPS-treated DCs. Collectively, our findings indicate that, in addition to Th1 immunity induced by BCG, RD1/ESAT-6-induced Th17 immune responses are essential for optimal vaccine efficacy.

  2. 17β-Estradiol regulates cell proliferation, colony formation, migration, invasion and promotes apoptosis by upregulating miR-9 and thus degrades MALAT-1 in osteosarcoma cell MG-63 in an estrogen receptor-independent manner

    Energy Technology Data Exchange (ETDEWEB)

    Fang, Dengfeng; Yang, Hui; Lin, Jing; Teng, Yi; Jiang, Yingying; Chen, Jiao; Li, Yu, E-mail: yuli_scu@163.com

    2015-02-20

    In bone, different concentration of estrogen leads to various of physiological processes in osteoblast, such as the proliferation, migration, and apoptosis in an estrogen receptor-dependent manner. But little was known about the estrogen effects on osteosarcoma (OS). In this study, OS cell MG-63 was treated with low (1 nM) or high (100 nM) dose of 17β-Estradiol (E2) with the presence or absence of estrogen receptor α (ERα), for evaluating the E2 effects on proliferation, migration, invasion, colony formation and apoptosis. Consistent with a previous study, high dose of E2 treatment dramatically downregulated expressing level of long non-coding RNA metastasis associated lung adenocarcinoma transcript 1 (MALAT-1). The observation of upregulation of miR-9 after a high dose of E2 treatment indicated the cause of MALAT-1 reduction. Downregulation of MALAT-1 promoted the combination of SFPQ/PTBP2 complex. It was also observed that the proliferation, migration, invasion, colony formation and apoptosis of OS cells were remarkably affected by high dose of E2 treatment, but not by low dose, in an ERα independent manner. Furthermore, the abolishment of the effects on these physiological processes caused by ectopic expression of miR-9 ASOs suggested the necessity of miR-9 in MALAT-1 regulation. Here we found that the high dose of E2 treatment upregulated miR-9 thus posttranscriptionally regulated MALAT-1 RNA level in OS cells, and then the downregulation of MALAT-1 inhibited cell proliferation, migration, invasion and epithelial–mesenchymal transition (EMT) processes in the E2-dose dependent and ER-independent ways. - Highlights: • E2 affects osteosarcoma cell MG-63 in an Estrogen receptor-independent way. • High dose of E2 treatment upregulates miR-9 which target to MALAT-1 RNA. • Upregulated miR-9 degrades MALAT-1 and thus affects combination of SFPQ/PTBP2. • E2 treatment block cell proliferation, colony formation, mobility, and enhance apoptosis.

  3. Somatostatin receptors

    DEFF Research Database (Denmark)

    Møller, Lars Neisig; Stidsen, Carsten Enggaard; Hartmann, Bolette

    2003-01-01

    therefore been acknowledged to be a third endogenous ligand at SRIF receptors. This review goes through mechanisms of signal transduction, pharmacology, and anatomical distribution of SRIF receptors. Structurally, SRIF receptors belong to the superfamily of G protein-coupled (GPC) receptors, sharing....... The generation of knock-out (KO) mice, intended as a means to define the contributions made by individual receptor subtypes, necessarily marks but an approximation. Furthermore, we must now take into account the stunning complexity of receptor co-operation indicated by the observation of receptor homo......-peptides, receptor agonists and antagonists. Relatively long half lives, as compared to those of the endogenous ligands, have been paramount from the outset. Motivated by theoretical puzzles or the shortcomings of present-day diagnostics and therapy, investigators have also aimed to produce subtype...

  4. NK-1 receptor antagonists as anti-cancer drugs

    Indian Academy of Sciences (India)

    The substance P (SP)/neurokinin (NK)-1 receptor system plays an important role in cancer. SP promotes the proliferation of tumour cells, angiogenesis and the migration of tumour cells. We review the involvement of SP, the NK-1 receptor and NK-1 receptor antagonists in cancer. Tumour cells overexpress NK-1 receptors, ...

  5. 24-Methylenecycloartanyl ferulate, a major compound of γ-oryzanol, promotes parvin-beta expression through an interaction with peroxisome proliferator-activated receptor-gamma 2 in human breast cancer cells

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Heon Woong; Lim, Eun Joung; Jang, Hwan Hee [Department of Agro-Food Resources, National Academy of Agricultural Science, Rural Department Administration, Wanju-gun, Jeollabuk-do 565-851 (Korea, Republic of); Cui, XueLei [Research Institute of Medical Science, KonKuk University, School of Medicine, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Kang, Da Rae [Department of Infection & Immunology, School of Medicine, KonKuk University 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of); Lee, Sung Hyen; Kim, Haeng Ran; Choe, Jeong Sook [Department of Agro-Food Resources, National Academy of Agricultural Science, Rural Department Administration, Wanju-gun, Jeollabuk-do 565-851 (Korea, Republic of); Yang, Young Mok [Department of Pathology, School of Medicine and Institute of Biomedical Science and Technology, Konkuk University, Seoul 143-701 (Korea, Republic of); Kim, Jung Bong, E-mail: jungbkim@korea.kr [Department of Agro-Food Resources, National Academy of Agricultural Science, Rural Department Administration, Wanju-gun, Jeollabuk-do 565-851 (Korea, Republic of); Park, Jong Hwan, E-mail: nihpark@yahoo.com [Research Institute of Medical Science, KonKuk University, School of Medicine, 120 Neungdong-ro, Gwangjin-gu, Seoul 143-701 (Korea, Republic of)

    2015-12-25

    Parvin-β is an adaptor protein that binds to integrin-linked kinase (ILK) and is significantly downregulated in breast tumors and breast cancer cell lines. We treated the breast cancer cell line MCF7 with 24-methylenecycloartanyl ferulate (24-MCF), a γ-oryzanol compound. We observed upregulation of parvin-β (GenBank Accession No. (AF237769)) and peroxisome proliferator-activated receptor (PPAR)-γ2 (GenBank Accession No. (NM-015869)). Among γ-oryzanol compounds, only treatment with 24-MCF led to the formation of reverse transcription-PCR products of parvin-β (650 and 500 bp) and PPAR-γ2 (580 bp) in MCF7 cells, but not in T47D, SK-BR-3, or MDA-MB-231 cells. 24-MCF treatment increased the mRNA and protein levels of parvin-β in MCF7 cells in a dose-dependent manner. We hypothesized that there is a correlation between parvin-β expression and induction of PPAR-γ2. This hypothesis was investigated by using a promoter-reporter assay, chromatin immunoprecipitation, and an electrophoretic mobility shift assay. 24-MCF treatment induced binding of PPAR-γ2 to a peroxisome proliferator response element-like cis-element (ACTAGGACAAAGGACA) in the parvin-β promoter in MCF7 cells in a dose-dependent manner. 24-MCF treatment significantly decreased anchorage-independent growth and inhibited cell movement in comparison to control treatment with dimethyl sulfoxide. 24-MCF treatment reduced the levels of GTP-bound Rac1 and Cdc42. Evaluation of Akt1 inhibition by 24-MCF revealed that the half maximal effective concentration was 33.3 μM. Docking evaluations revealed that 24-MCF binds to the ATP-binding site of Akt1(PDB ID: (3OCB)) and the compound binding energy is -8.870 kcal/mol. Taken together, our results indicate that 24-MCF treatment increases parvin-β expression, which may inhibit ILK downstream signaling. - Highlights: • Treatment with 24-MCF increases gene expression of parvin-β and PPAR-ϒ2 in MCF7 cells. • PPAR-ϒ2 interacts with the parvin-β gene via

  6. 24-Methylenecycloartanyl ferulate, a major compound of γ-oryzanol, promotes parvin-beta expression through an interaction with peroxisome proliferator-activated receptor-gamma 2 in human breast cancer cells

    International Nuclear Information System (INIS)

    Kim, Heon Woong; Lim, Eun Joung; Jang, Hwan Hee; Cui, XueLei; Kang, Da Rae; Lee, Sung Hyen; Kim, Haeng Ran; Choe, Jeong Sook; Yang, Young Mok; Kim, Jung Bong; Park, Jong Hwan

    2015-01-01

    Parvin-β is an adaptor protein that binds to integrin-linked kinase (ILK) and is significantly downregulated in breast tumors and breast cancer cell lines. We treated the breast cancer cell line MCF7 with 24-methylenecycloartanyl ferulate (24-MCF), a γ-oryzanol compound. We observed upregulation of parvin-β (GenBank Accession No. (AF237769)) and peroxisome proliferator-activated receptor (PPAR)-γ2 (GenBank Accession No. (NM_015869)). Among γ-oryzanol compounds, only treatment with 24-MCF led to the formation of reverse transcription-PCR products of parvin-β (650 and 500 bp) and PPAR-γ2 (580 bp) in MCF7 cells, but not in T47D, SK-BR-3, or MDA-MB-231 cells. 24-MCF treatment increased the mRNA and protein levels of parvin-β in MCF7 cells in a dose-dependent manner. We hypothesized that there is a correlation between parvin-β expression and induction of PPAR-γ2. This hypothesis was investigated by using a promoter-reporter assay, chromatin immunoprecipitation, and an electrophoretic mobility shift assay. 24-MCF treatment induced binding of PPAR-γ2 to a peroxisome proliferator response element-like cis-element (ACTAGGACAAAGGACA) in the parvin-β promoter in MCF7 cells in a dose-dependent manner. 24-MCF treatment significantly decreased anchorage-independent growth and inhibited cell movement in comparison to control treatment with dimethyl sulfoxide. 24-MCF treatment reduced the levels of GTP-bound Rac1 and Cdc42. Evaluation of Akt1 inhibition by 24-MCF revealed that the half maximal effective concentration was 33.3 μM. Docking evaluations revealed that 24-MCF binds to the ATP-binding site of Akt1(PDB ID: (3OCB)) and the compound binding energy is -8.870 kcal/mol. Taken together, our results indicate that 24-MCF treatment increases parvin-β expression, which may inhibit ILK downstream signaling. - Highlights: • Treatment with 24-MCF increases gene expression of parvin-β and PPAR-ϒ2 in MCF7 cells. • PPAR-ϒ2 interacts with the parvin-β gene via

  7. HDAC2 and HDAC5 Up-Regulations Modulate Survivin and miR-125a-5p Expressions and Promote Hormone Therapy Resistance in Estrogen Receptor Positive Breast Cancer Cells

    Directory of Open Access Journals (Sweden)

    Wen-Tsung Huang

    2017-12-01

    Full Text Available Intrinsic or acquired resistance to hormone therapy is frequently reported in estrogen receptor positive (ER+ breast cancer patients. Even though dysregulations of histone deacetylases (HDACs are known to promote cancer cells survival, the role of different HDACs in the induction of hormone therapy resistance in ER+ breast cancer remains unclear. Survivin is a well-known pro-tumor survival molecule and miR-125a-5p is a recently discovered tumor suppressor. In this study, we found that ER+, hormone-independent, tamoxifen-resistant MCF7-TamC3 cells exhibit increased expression of HDAC2, HDAC5, and survivin, but show decreased expression of miR-125a-5p, as compared to the parental tamoxifen-sensitive MCF7 breast cancer cells. Molecular down-regulations of HDAC2, HDAC5, and survivin, and ectopic over-expression of miR-125a-5p, increased the sensitivity of MCF7-TamC3 cells to estrogen deprivation and restored the sensitivity to tamoxifen. The same treatments also further increased the sensitivity to estrogen-deprivation in the ER+ hormone-dependent ZR-75-1 breast cancer cells in vitro. Kaplan–Meier analysis and receiver operating characteristic curve analysis of expression cohorts of breast tumor showed that high HDAC2 and survivin, and low miR-125a-5p, expression levels correlate with poor relapse-free survival in endocrine therapy and tamoxifen-treated ER+ breast cancer patients. Further molecular analysis revealed that HDAC2 and HDAC5 positively modulates the expression of survivin, and negatively regulates the expression miR-125a-5p, in ER+ MCF7, MCF7-TamC3, and ZR-75-1 breast cancer cells. These findings indicate that dysregulations of HDAC2 and HDAC5 promote the development of hormone independency and tamoxifen resistance in ERC breast cancer cells in part through expression regulation of survivin and miR-125a-5p.

  8. The substance P/NK-1 receptor system: NK-1 receptor antagonists ...

    Indian Academy of Sciences (India)

    2015-04-27

    Apr 27, 2015 ... The substance P (SP)/neurokinin (NK)-1 receptor system plays an important role in cancer. SP promotes the ... NK-1 receptor may be a promising target in the treatment of cancer; NK-1 receptor antagonists could act as specific ...... mycin, ifosfamide, cisplatin) in MG-63 human osteosarcoma cells, but not in ...

  9. microRNA-4331 Promotes Transmissible Gastroenteritis Virus (TGEV)-induced Mitochondrial Damage Via Targeting RB1, Upregulating Interleukin-1 Receptor Accessory Protein (IL1RAP), and Activating p38 MAPK Pathway In Vitro*

    Science.gov (United States)

    Zhao, Xiaomin; Bai, Xiaoyuan; Guan, Lijuan; Li, Juejun; Song, Xiangjun; Ma, Xuelian; Guo, Jianxiong; Zhang, Zhichao; Du, Qian; Huang, Yong; Tong, Dewen

    2018-01-01

    Transmissible gastroenteritis virus (TGEV), a member of the coronaviridae family, could cause fatal diarrhea of piglets and result in numerous economic losses. Previous studies demonstrated that TGEV infection could lead to mitochondrial damage and upregulate miR-4331 level. So miR-4331 may play an important regulatory role in the control of mitochondrial function. To explore the potential role of miR-4331 in mitochondrial damage, we adopted a strategy consisting of quantitative proteomic analysis of porcine kidney (PK-15) cells in response to miR-4331 and TGEV infection. Eventually, 69 differentially expressed proteins were gained. The target of miR-4331 was identified. The effects of miR-4331 and its target RB1 on mitochondrial Ca2+ level, mitochondrial membrane potential (MMP), interleukin-1 receptor accessory protein (IL1RAP), p38 MAPK signaling pathway were investigated. The results showed that miR-4331 elevated mitochondrial Ca2+ level, reduced MMP, targets Retinoblastoma 1 (RB1), upregulated IL1RAP, and induced activation of p38 MAPK pathway during TGEV infection. RB1 was identified as the direct targets of miR-4331 and downregulated IL1RAP, suppressed the activation of p38 MPAK, and attenuated TGEV-induced mitochondrial damage. In addition, IL1RAP played a positive role in activating p38 MAPK signaling and negative role in TGEV-induced mitochondrial damage. The data indicate that miR-4331 aggravates TGEV-induced mitochondrial damage by repressing expression of RB1, promoting IL1RAP, and activating p38 MAPK pathway. PMID:29217619

  10. microRNA-4331 Promotes Transmissible Gastroenteritis Virus (TGEV)-induced Mitochondrial Damage Via Targeting RB1, Upregulating Interleukin-1 Receptor Accessory Protein (IL1RAP), and Activating p38 MAPK PathwayIn Vitro.

    Science.gov (United States)

    Zhao, Xiaomin; Bai, Xiaoyuan; Guan, Lijuan; Li, Juejun; Song, Xiangjun; Ma, Xuelian; Guo, Jianxiong; Zhang, Zhichao; Du, Qian; Huang, Yong; Tong, Dewen

    2018-02-01

    Transmissible gastroenteritis virus (TGEV), a member of the coronaviridae family, could cause fatal diarrhea of piglets and result in numerous economic losses. Previous studies demonstrated that TGEV infection could lead to mitochondrial damage and upregulate miR-4331 level. So miR-4331 may play an important regulatory role in the control of mitochondrial function. To explore the potential role of miR-4331 in mitochondrial damage, we adopted a strategy consisting of quantitative proteomic analysis of porcine kidney (PK-15) cells in response to miR-4331 and TGEV infection. Eventually, 69 differentially expressed proteins were gained. The target of miR-4331 was identified. The effects of miR-4331 and its target RB1 on mitochondrial Ca 2+ level, mitochondrial membrane potential (MMP), interleukin-1 receptor accessory protein (IL1RAP), p38 MAPK signaling pathway were investigated. The results showed that miR-4331 elevated mitochondrial Ca 2+ level, reduced MMP, targets Retinoblastoma 1 (RB1), upregulated IL1RAP, and induced activation of p38 MAPK pathway during TGEV infection. RB1 was identified as the direct targets of miR-4331 and downregulated IL1RAP, suppressed the activation of p38 MPAK, and attenuated TGEV-induced mitochondrial damage. In addition, IL1RAP played a positive role in activating p38 MAPK signaling and negative role in TGEV-induced mitochondrial damage. The data indicate that miR-4331 aggravates TGEV-induced mitochondrial damage by repressing expression of RB1, promoting IL1RAP, and activating p38 MAPK pathway. © 2018 by The American Society for Biochemistry and Molecular Biology, Inc.

  11. The Phosphoinositide 3-Kinase p110α Isoform Regulates Leukemia Inhibitory Factor Receptor Expression via c-Myc and miR-125b to Promote Cell Proliferation in Medulloblastoma.

    Directory of Open Access Journals (Sweden)

    Fabiana Salm

    Full Text Available Medulloblastoma (MB is the most common malignant brain tumor in childhood and represents the main cause of cancer-related death in this age group. The phosphoinositide 3-kinase (PI3K pathway has been shown to play an important role in the regulation of medulloblastoma cell survival and proliferation, but the molecular mechanisms and downstream effectors underlying PI3K signaling still remain elusive. The impact of RNA interference (RNAi-mediated silencing of PI3K isoforms p110α and p110δ on global gene expression was investigated by DNA microarray analysis in medulloblastoma cell lines. A subset of genes with selectively altered expression upon p110α silencing in comparison to silencing of the closely related p110δ isoform was revealed. Among these genes, the leukemia inhibitory factor receptor α (LIFR α was validated as a novel p110α target in medulloblastoma. A network involving c-Myc and miR-125b was shown to be involved in the control of LIFRα expression downstream of p110α. Targeting the LIFRα by RNAi, or by using neutralizing reagents impaired medulloblastoma cell proliferation in vitro and induced a tumor volume reduction in vivo. An analysis of primary tumors revealed that LIFRα and p110α expression were elevated in the sonic hedgehog (SHH subgroup of medulloblastoma, indicating its clinical relevance. Together, these data reveal a novel molecular signaling network, in which PI3K isoform p110α controls the expression of LIFRα via c-Myc and miR-125b to promote MB cell proliferation.

  12. Somatostatin receptors

    DEFF Research Database (Denmark)

    Møller, Lars Neisig; Stidsen, Carsten Enggaard; Hartmann, Bolette

    2003-01-01

    therefore been acknowledged to be a third endogenous ligand at SRIF receptors. This review goes through mechanisms of signal transduction, pharmacology, and anatomical distribution of SRIF receptors. Structurally, SRIF receptors belong to the superfamily of G protein-coupled (GPC) receptors, sharing......- and heterodimerisation, let alone oligomerisation. Theoretically, this phenomenon adds a novel series of functional megareceptors/super-receptors, with varied pharmacological profiles, to the catalogue of monomeric receptor subtypes isolated and cloned in the past. SRIF analogues include both peptides and non......-peptides, receptor agonists and antagonists. Relatively long half lives, as compared to those of the endogenous ligands, have been paramount from the outset. Motivated by theoretical puzzles or the shortcomings of present-day diagnostics and therapy, investigators have also aimed to produce subtype...

  13. Differences in 5-HT2A and mGlu2 Receptor Expression Levels and Repressive Epigenetic Modifications at the 5-HT2A Promoter Region in the Roman Low- (RLA-I) and High- (RHA-I) Avoidance Rat Strains.

    Science.gov (United States)

    Fomsgaard, Luna; Moreno, Jose L; de la Fuente Revenga, Mario; Brudek, Tomasz; Adamsen, Dea; Rio-Alamos, Cristobal; Saunders, Justin; Klein, Anders Bue; Oliveras, Ignasi; Cañete, Toni; Blazquez, Gloria; Tobeña, Adolf; Fernandez-Teruel, Albert; Gonzalez-Maeso, Javier; Aznar, Susana

    2018-03-01

    The serotonin 2A (5-HT 2A ) and metabotropic glutamate 2 (mGlu2) receptors regulate each other and are associated with schizophrenia. The Roman high- (RHA-I) and the Roman low- (RLA-I) avoidance rat strains present well-differentiated behavioral profiles, with the RHA-I strain emerging as a putative genetic rat model of schizophrenia-related features. The RHA-I strain shows increased 5-HT 2A and decreased mGlu2 receptor binding levels in prefrontal cortex (PFC). Here, we looked for differences in gene expression and transcriptional regulation of these receptors. The striatum (STR) was included in the analysis. 5-HT 2A , 5-HT 1A , and mGlu2 mRNA and [ 3 H]ketanserin binding levels were measured in brain homogenates. As expected, 5-HT 2A binding was significantly increased in PFC in the RHA-I rats, while no difference in binding was observed in STR. Surprisingly, 5-HT 2A gene expression was unchanged in PFC but significantly decreased in STR. mGlu2 receptor gene expression was significantly decreased in both PFC and STR. No differences were observed for the 5-HT 1A receptor. Chromatin immunoprecipitation assay revealed increased trimethylation of histone 3 at lysine 27 (H3K27me3) at the promoter region of the HTR2A gene in the STR. We further looked at the Akt/GSK3 signaling pathway, a downstream point of convergence of the serotonin and glutamate system, and found increased phosphorylation levels of GSK3β at tyrosine 216 and increased β-catenin levels in the PFC of the RHA-I rats. These results reveal region-specific regulation of the 5-HT 2A receptor in the RHA-I rats probably due to absence of mGlu2 receptor that may result in differential regulation of downstream pathways.

  14. Metazoan promoters

    DEFF Research Database (Denmark)

    Lenhard, Boris; Sandelin, Albin Gustav; Carninci, Piero

    2012-01-01

    Promoters are crucial for gene regulation. They vary greatly in terms of associated regulatory elements, sequence motifs, the choice of transcription start sites and other features. Several technologies that harness next-generation sequencing have enabled recent advances in identifying promoters ...

  15. Health Promotion

    DEFF Research Database (Denmark)

    Povlsen, Lene; Borup, I.

    2015-01-01

    , the World Health Organization made a crucial change to view health not as a goal in itself but as the means to a full life. In this way, health promotion became a first priority and fundamental action for the modern society. This insight eventually reached NHV and in 2002 - 50 years after the foundation......In 1953 when the Nordic School of Public Health was founded, the aim of public health programmes was disease prevention more than health promotion. This was not unusual, since at this time health usually was seen as the opposite of disease and illness. However, with the Ottawa Charter of 1986...... - an associate professorship was established with a focus on health promotion. Nevertheless, the concept of health promotion had been integrated with or mentioned in courses run prior to the new post. Subsequently, a wide spectrum of courses in health promotion was introduced, such as Empowerment for Child...

  16. ANTIGENIC PROMOTION

    Science.gov (United States)

    Wu, Chin-Yu; Cinader, Bernard

    1971-01-01

    Rabbits were immunized with p-azobenzene arsonic acid derivatives of human serum albumin (HA-As) or of dissociated keyhole limpet hemocyanin. The IgM response to the hapten was evaluated in terms of the number of hapten-specific plaque-forming cells in the lymph node draining the injection site. In some experiments, antibody was measured by agglutination of tanned and sensitized erythrocytes. The hapten response of animals immunized with HA-As was increased (promoting effect) when the animals were injected with one of several structurally unrelated macromolecules: keyhole limpet hemocyanin (KLH), horse spleen ferritin (HSF), lysozyme (Lys), alum-precipitated human gamma globulin (alum-precipitated HGG). Different macromolecules differed in the magnitude of the promoting effect they induced, e.g., promotion by the associated form of KLH was greater than that by the dissociated form; alum-precipitated HGG was a better promoter than was soluble HGG. The relative magnitude of promotion by different macromolecules (associated vs. dissociated KLH, alum-precipitated vs. soluble HGG) correlated with the relative magnitude of the carrier effect, as judged by the hapten response induced by p-azobenzene arsonic acid conjugated to various proteins. Promotion was detected by agglutination assay of circulating antibody, by plaque assay of cells from the popliteal lymph node draining the site of preinjection, but not by plaque assay of cells from the contralateral lymph node. Promotion was dependent on the dose of the promoting macromolecule and on the dose of the hapten-protein conjugate. It was not observed in animals tolerant to the promoting macromolecule. Inhibition (i.e. antigenic competition), rather than promotion, was observed upon a secondary response to the preinjected macromolecule or when the hapten-protein conjugate was incorporated in Freund's adjuvant. PMID:15776570

  17. Thermogenic characterization of ghrelin receptor null mice

    Science.gov (United States)

    Ghrelin is the only known circulating orexigenic hormone that increases food intake and promotes adiposity, and these physiological functions of ghrelin are mediated through its receptor growth hormone secretagogue receptor (GHS-R). Ghrelin/GHS-R signaling plays a crucial role in energy homeostasis....

  18. Acute 5-HT7 receptor activation increases NMDA-evoked currents and differentially alters NMDA receptor subunit phosphorylation and trafficking in hippocampal neurons.

    Science.gov (United States)

    Vasefi, Maryam S; Yang, Kai; Li, Jerry; Kruk, Jeff S; Heikkila, John J; Jackson, Michael F; MacDonald, John F; Beazely, Michael A

    2013-05-14

    N-methyl-D-aspartate (NMDA) receptors are regulated by several G protein-coupled receptors (GPCRs) as well as receptor tyrosine kinases. Serotonin (5-HT) type 7 receptors are expressed throughout the brain including the thalamus and hippocampus. Long-term (2-24 h) activation of 5-HT7 receptors promotes the expression of neuroprotective growth factor receptors, including the platelet-derived growth factor (PDGF) β receptors which can protect neurons against NMDA-induced neurotoxicity. In contrast to long-term activation of 5-HT7 receptors, acute (5 min) treatment of isolated hippocampal neurons with the 5-HT7 receptor agonist 5-carboxamidotryptamine (5-CT) enhances NMDA-evoked peak currents and this increase in peak currents is blocked by the 5-HT7 receptor antagonist, SB 269970. In hippocampal slices, acute 5-HT7 receptor activation increases NR1 NMDA receptor subunit phosphorylation and differentially alters the phosphorylation state of the NR2B and NR2A subunits. NMDA receptor subunit cell surface expression is also differentially altered by 5-HT7 receptor agonists: NR2B cell surface expression is decreased whereas NR1 and NR2A surface expression are not significantly altered. In contrast to the negative regulatory effects of long-term activation of 5-HT7 receptors on NMDA receptor signaling, acute activation of 5-HT7 receptors promotes NMDA receptor activity. These findings highlight the potential for temporally differential regulation of NMDA receptors by the 5-HT7 receptor.

  19. Regulation of prolactin receptor (PRLR) gene expression in insulin-producing cells. Prolactin and growth hormone activate one of the rat prlr gene promoters via STAT5a and STAT5b

    DEFF Research Database (Denmark)

    Galsgaard, E D; Møldrup, Annette; Nielsen, Jens Høiriis

    1999-01-01

    Expression of the prolactin receptor (PRLR) gene is increased in pancreatic islets during pregnancy and in vitro in insulin-producing cells by growth hormone (GH) and prolactin (PRL). The 5'-region of the rat PRLR gene contains at least three alternative first exons that are expressed tissue...

  20. P17, an Original Host Defense Peptide from Ant Venom, Promotes Antifungal Activities of Macrophages through the Induction of C-Type Lectin Receptors Dependent on LTB4-Mediated PPARγ Activation

    Directory of Open Access Journals (Sweden)

    Khaddouj Benmoussa

    2017-11-01

    Full Text Available Despite the growing knowledge with regard to the immunomodulatory properties of host defense peptides, their impact on macrophage differentiation and on its associated microbicidal functions is still poorly understood. Here, we demonstrated that the P17, a new cationic antimicrobial peptide from ant venom, induces an alternative phenotype of human monocyte-derived macrophages (h-MDMs. This phenotype is characterized by a C-type lectin receptors (CLRs signature composed of mannose receptor (MR and Dectin-1 expression. Concomitantly, this activation is associated to an inflammatory profile characterized by reactive oxygen species (ROS, interleukin (IL-1β, and TNF-α release. P17-activated h-MDMs exhibit an improved capacity to recognize and to engulf Candida albicans through the overexpression both of MR and Dectin-1. This upregulation requires arachidonic acid (AA mobilization and the activation of peroxisome proliferator-activated receptor gamma (PPARγ nuclear receptor through the leukotriene B4 (LTB4 production. AA/LTB4/PPARγ/Dectin-1-MR signaling pathway is crucial for P17-mediated anti-fungal activity of h-MDMs, as indicated by the fact that the activation of this axis by P17 triggered ROS production and inflammasome-dependent IL-1β release. Moreover, we showed that the increased anti-fungal immune response of h-MDMs by P17 was dependent on intracellular calcium mobilization triggered by the interaction of P17 with pertussis toxin-sensitive G-protein-coupled receptors on h-MDMs. Finally, we also demonstrated that P17-treated mice infected with C. albicans develop less severe gastrointestinal infection related to a higher efficiency of their macrophages to engulf Candida, to produce ROS and IL-1β and to kill the yeasts. Altogether, these results identify P17 as an original activator of the fungicidal response of macrophages that acts upstream PPARγ/CLRs axis and offer new immunomodulatory therapeutic perspectives in the field of

  1. Glutamate receptors

    DEFF Research Database (Denmark)

    Kristensen, Anders S; Geballe, Matthew T; Snyder, James P

    2006-01-01

    Fast excitatory synaptic transmission in the CNS relies almost entirely on the neurotransmitter glutamate and its family of ion channel receptors. An appreciation of the coupling between agonist binding and channel opening has advanced rapidly during the past five years, largely as a result of ne...

  2. Data describing the effect of DRD4 promoter polymorphisms on promoter activity

    Directory of Open Access Journals (Sweden)

    Shoin Tei

    2016-06-01

    Full Text Available This data article tested whether polymorphisms within the dopamine D4 receptor (DRD4 gene promoter can lead to differences in the promoter activity. The variants, a 120-bp variable number tandem repeat (VNTR, −906 T/C, −809 G/A, −616G/C, and −521C/T, were introduced into the DRD4 promoter and the promoter activity was measured in a neural cell line using the luciferase assay. However, no differences were detected among the haplotypes investigated, and the in vitro data obtained from our protocol could not support the involvement of DRD4 promoter polymorphisms in heritable human traits.

  3. Dynamic mobility of functional GABAA receptors at inhibitory synapses.

    Science.gov (United States)

    Thomas, Philip; Mortensen, Martin; Hosie, Alastair M; Smart, Trevor G

    2005-07-01

    Importing functional GABAA receptors into synapses is fundamental for establishing and maintaining inhibitory transmission and for controlling neuronal excitability. By introducing a binding site for an irreversible inhibitor into the GABAA receptor alpha1 subunit channel lining region that can be accessed only when the receptor is activated, we have determined the dynamics of receptor mobility between synaptic and extrasynaptic locations in hippocampal pyramidal neurons. We demonstrate that the cell surface GABAA receptor population shows no fast recovery after irreversible inhibition. In contrast, after selective inhibition, the synaptic receptor population rapidly recovers by the import of new functional entities within minutes. The trafficking pathways that promote rapid importation of synaptic receptors do not involve insertion from intracellular pools, but reflect receptor diffusion within the plane of the membrane. This process offers the synapse a rapid mechanism to replenish functional GABAA receptors at inhibitory synapses and a means to control synaptic efficacy.

  4. Molecular analysis of the nerve growth factor receptor

    International Nuclear Information System (INIS)

    Hempstead, B.; Patil, N.; Olson, K.; Chao, M.

    1988-01-01

    An essential molecule in the translocation of information by nerve growth factor (NGF) to responsive cells is the cell-surface receptor for NGF. This paper presents information on the genomic structure of the NGF receptor gene, NGF receptor models, and transfection of NGF receptors. Equilibrium binding of [ 125 I]NGF to cells reveals two distinct affinity states for the NGF receptor. The human NGF receptor gene is a single-copy gene, consisting of six exons that span 23 kb. The receptor gene is capable of being transferred to fibroblast cells from human genomic DNA and expressed at high levels. The constitutive nature of the receptor promoter sequence is a partial explanation of why this tissue-specific gene is expressed efficiently in a variety of nonneuronal cells after genomic gene transfer. The two kinetic forms of the NGF receptor appear to be encoded by the same protein, which is the product of a single gene

  5. G-protein coupled receptor 56 promotes myoblast fusion through serum response factor- and nuclear factor of activated T-cell-mediated signalling but is not essential for muscle development in vivo.

    Science.gov (United States)

    Wu, Melissa P; Doyle, Jamie R; Barry, Brenda; Beauvais, Ariane; Rozkalne, Anete; Piao, Xianhua; Lawlor, Michael W; Kopin, Alan S; Walsh, Christopher A; Gussoni, Emanuela

    2013-12-01

    Mammalian muscle cell differentiation is a complex process of multiple steps for which many of the factors involved have not yet been defined. In a screen to identify the regulators of myogenic cell fusion, we found that the gene for G-protein coupled receptor 56 (GPR56) was transiently up-regulated during the early fusion of human myoblasts. Human mutations in the gene for GPR56 cause the disease bilateral frontoparietal polymicrogyria; however, the consequences of receptor dysfunction on muscle development have not been explored. Using knockout mice, we defined the role of GPR56 in skeletal muscle. GPR56(-/-) myoblasts have decreased fusion and smaller myotube sizes in culture. In addition, a loss of GPR56 expression in muscle cells results in decreases or delays in the expression of myogenic differentiation 1, myogenin and nuclear factor of activated T-cell (NFAT)c2. Our data suggest that these abnormalities result from decreased GPR56-mediated serum response element and NFAT signalling. Despite these changes, no overt differences in phenotype were identified in the muscle of GPR56 knockout mice, which presented only a mild but statistically significant elevation of serum creatine kinase compared to wild-type. In agreement with these findings, clinical data from 13 bilateral frontoparietal polymicrogyria patients revealed mild serum creatine kinase increase in only two patients. In summary, targeted disruption of GPR56 in mice results in myoblast abnormalities. The absence of a severe muscle phenotype in GPR56 knockout mice and human patients suggests that other factors may compensate for the lack of this G-protein coupled receptor during muscle development and that the motor delay observed in these patients is likely not a result of primary muscle abnormalities. © 2013 FEBS.

  6. Promoting industrialisation

    International Nuclear Information System (INIS)

    Hayfield, F.

    1986-04-01

    When the first nuclear power programme is decided upon, automatically the country has to initiate in parallel a programme to modify or add to its current industrial structure and resources. The extent of this new industrialisation depends upon many factors which both, the Government and the Industries have to consider. The Government has a vital role which includes the setting up of the background against which the industrial promotion should take place and in many cases may have also to play an active role all along this programme. Equally, the existing industries have an important role so as to achieve the most efficient participation in the nuclear programme. Invariably the industrial promotional programme will incur a certain degree of transfer of technology, the extent depending on the policies adopted. For this technology transfer to take place efficiently, both the donor and the receiver have to recognise each other's legitimate ambitions and fears. The transfer of technology is a process having a high human content and both donor and receiver have to take this into account. This can be further complicated when there is a difference in culture between them. Technology transfer is carried out within a contractual and organisational framework which will identify the donor (licensor) and the receiver (licensee). This framework may take various forms from a simple cooperative agreement, through a joint-venture organisation right to a standard contract between two separate entities. Each arrangement has its advantages and drawbacks and requires investment of different degrees. One of the keys to a successful industrial promotion is having it carried out in a timely fashion which will be parallel with the nuclear power programme. Experience in some countries has shown the problems when the industrialisation is out of phase with the programme whilst in other cases this industrialisation was at a level and scale unjustified. (author)

  7. Atypical chemokine receptors in cancer: friends or foes?

    Science.gov (United States)

    Massara, Matteo; Bonavita, Ornella; Mantovani, Alberto; Locati, Massimo; Bonecchi, Raffaella

    2016-06-01

    The chemokine system is a fundamental component of cancer-related inflammation involved in all stages of cancer development. It controls not only leukocyte infiltration in primary tumors but also angiogenesis, cancer cell proliferation, and migration to metastatic sites. Atypical chemokine receptors are a new, emerging class of regulators of the chemokine system. They control chemokine bioavailability by scavenging, transporting, or storing chemokines. They can also regulate the activity of canonical chemokine receptors with which they share the ligands by forming heterodimers or by modulating their expression levels or signaling activity. Here, we summarize recent results about the role of these receptors (atypical chemokine receptor 1/Duffy antigen receptor for chemokine, atypical chemokine receptor 2/D6, atypical chemokine receptor 3/CXC-chemokine receptor 7, and atypical chemokine receptor 4/CC-chemokine receptor-like 1) on the tumorigenesis process, indicating that their effects are strictly dependent on the cell type on which they are expressed and on their coexpression with other chemokine receptors. Indeed, atypical chemokine receptors inhibit tumor growth and progression through their activity as negative regulators of chemokine bioavailability, whereas, on the contrary, they can promote tumorigenesis when they regulate the signaling of other chemokine receptors, such as CXC-chemokine receptor 4. Thus, atypical chemokine receptors are key components of the regulatory network of inflammation and immunity in cancer and may have a major effect on anti-inflammatory and immunotherapeutic strategies. © Society for Leukocyte Biology.

  8. Hyperoside Downregulates the Receptor for Advanced Glycation End Products (RAGE and Promotes Proliferation in ECV304 Cells via the c-Jun N-Terminal Kinases (JNK Pathway Following Stimulation by Advanced Glycation End-Products In Vitro

    Directory of Open Access Journals (Sweden)

    Zhengyu Zhang

    2013-11-01

    Full Text Available Hyperoside is a major active constituent in many medicinal plants which are traditionally used in Chinese medicines for their neuroprotective, anti-inflammatory and antioxidative effects. The molecular mechanisms underlying these effects are unknown. In this study, quiescent ECV304 cells were treated in vitro with advanced glycation end products (AGEs in the presence or absence of hyperoside. The results demonstrated that AGEs induced c-Jun N-terminal kinases (JNK activation and apoptosis in ECV304 cells. Hyperoside inhibited these effects and promoted ECV304 cell proliferation. Furthermore, hyperoside significantly inhibited RAGE expression in AGE-stimulated ECV304 cells, whereas knockdown of RAGE inhibited AGE-induced JNK activation. These results suggested that AGEs may promote JNK activation, leading to viability inhibition of ECV304 cells via the RAGE signaling pathway. These effects could be inhibited by hyperoside. Our findings suggest a novel role for hyperoside in the treatment and prevention of diabetes.

  9. Hyperoside Downregulates the Receptor for Advanced Glycation End Products (RAGE) and Promotes Proliferation in ECV304 Cells via the c-Jun N-Terminal Kinases (JNK) Pathway Following Stimulation by Advanced Glycation End-Products In Vitro

    Science.gov (United States)

    Zhang, Zhengyu; Sethiel, Mosha Silas; Shen, Weizhi; Liao, Sentai; Zou, Yuxiao

    2013-01-01

    Hyperoside is a major active constituent in many medicinal plants which are traditionally used in Chinese medicines for their neuroprotective, anti-inflammatory and antioxidative effects. The molecular mechanisms underlying these effects are unknown. In this study, quiescent ECV304 cells were treated in vitro with advanced glycation end products (AGEs) in the presence or absence of hyperoside. The results demonstrated that AGEs induced c-Jun N-terminal kinases (JNK) activation and apoptosis in ECV304 cells. Hyperoside inhibited these effects and promoted ECV304 cell proliferation. Furthermore, hyperoside significantly inhibited RAGE expression in AGE-stimulated ECV304 cells, whereas knockdown of RAGE inhibited AGE-induced JNK activation. These results suggested that AGEs may promote JNK activation, leading to viability inhibition of ECV304 cells via the RAGE signaling pathway. These effects could be inhibited by hyperoside. Our findings suggest a novel role for hyperoside in the treatment and prevention of diabetes. PMID:24252909

  10. Regulation of prolactin receptor (PRLR) gene expression in insulin-producing cells. Prolactin and growth hormone activate one of the rat prlr gene promoters via STAT5a and STAT5b

    DEFF Research Database (Denmark)

    Galsgaard, E D; Møldrup, Annette; Nielsen, Jens Høiriis

    1999-01-01

    -specifically because of differential promoter usage. We show by reverse transcription-polymerase chain reaction analysis that both exon 1A- and exon 1C-containing PRLR transcripts are expressed in rat islets and that human (h)GH, ovine (o)PRL, and bovine (b)GH increase exon 1A expression 6.5 +/- 0. 8-fold, 6.8 +/- 0......-fold, respectively, above that of a promoterless reporter construct when transfected into the insulin-producing INS-1 cells. The transcriptional activity of the 1A promoter construct was increased 8.9 +/- 1.9-fold by 0.5 microgram/ml hGH. Responsiveness to hGH of the 1A promoter was localized...... to the region from -225 to +81 with respect to the transcription start site. This region contains the sequence TTCTAGGAA that by gel retardation experiments was shown to bind the transcription factors STAT5a and STAT5b in response to stimulation by hGH, oPRL, or bGH. Mutation of this gamma-activated sequence...

  11. Orexin Receptors: Pharmacology and Therapeutic Opportunities

    Science.gov (United States)

    Scammell, Thomas E.; Winrow, Christopher J.

    2011-01-01

    Orexin-A and -B (also known as hypocretin-1 and -2) are neuropeptides produced in the lateral hypothalamus that promote many aspects of arousal through the OX1 and OX2 receptors. In fact, they are necessary for normal wakefulness, as loss of the orexin-producing neurons causes narcolepsy in humans and rodents. This has generated considerable interest in developing small-molecule orexin receptor antagonists as a novel therapy for the treatment of insomnia. Orexin antagonists, especially those that block OX2 or both OX1 and OX2 receptors, clearly promote sleep in animals, and clinical results are encouraging: Several compounds are in Phase III trials. As the orexin system mainly promotes arousal, these new compounds will likely improve insomnia without incurring many of the side effects encountered with current medications. PMID:21034217

  12. Sphingosine-1-Phosphate/Sphingosine-1-Phosphate Receptor 2 Axis Can Promote Mouse and Human Primary Mast Cell Angiogenic Potential through Upregulation of Vascular Endothelial Growth Factor-A and Matrix Metalloproteinase-2

    Directory of Open Access Journals (Sweden)

    Alena Chumanevich

    2016-01-01

    Full Text Available Mast cells (MC are present in most vascularized tissues around the vasculature likely exerting immunomodulatory functions. Endowed with diverse mediators, resident MC represent first-line fine-tuners of local microenvironment. Sphingosine-1-phosphate (S1P functions as a pluripotent signaling sphingolipid metabolite in health and disease. S1P formation occurs at low levels in resting MC and is upregulated upon activation. Its export can result in type 2 S1P receptor- (S1PR2- mediated stimulation of MC, further fueling inflammation. However, the role of S1PR2 ligation in proangiogenic vascular endothelial growth factor- (VEGF- A and matrix metalloproteinase- (MMP- 2 release from MC is unknown. Using a preclinical MC-dependent model of acute allergic responses and in vitro stimulated primary mouse bone marrow-derived MC (BMMC or human primary skin MC, we report that S1P signaling resulted in substantial amount of VEGF-A release. Similar experiments using S1pr2-deficient mice or BMMC or selective S1P receptor agonists or antagonists demonstrated that S1P/S1PR2 ligation on MC is important for VEGF-A secretion. Further, we show that S1P stimulation triggered transcriptional upregulation of VEGF-A and MMP-2 mRNA in human but not in mouse MC. S1P exposure also triggered MMP-2 secretion from human MC. These studies identify a novel proangiogenic axis encompassing MC/S1P/S1PR2 likely relevant to inflammation.

  13. The Membrane Protein of Severe Acute Respiratory Syndrome Coronavirus Functions as a Novel Cytosolic Pathogen-Associated Molecular Pattern To Promote Beta Interferon Induction via a Toll-Like-Receptor-Related TRAF3-Independent Mechanism

    Directory of Open Access Journals (Sweden)

    Yi Wang

    2016-02-01

    Full Text Available Most of the intracellular pattern recognition receptors (PRRs reside in either the endolysosome or the cytoplasm to sense pathogen-derived RNAs, DNAs, or synthetic analogs of double-stranded RNA (dsRNA, such as poly(I:C. However, it remains elusive whether or not a pathogen-derived protein can function as a cytosolic pathogen-associated molecular pattern (PAMP. In this study, we demonstrate that delivering the membrane gene of severe acute respiratory syndrome coronavirus (SARS-CoV into HEK293T, HEK293ET, and immobilized murine bone marrow-derived macrophage (J2-Mφ cells significantly upregulates beta interferon (IFN-β production. Both NF-κB and TBK1-IRF3 signaling cascades are activated by M gene products. M protein rather than M mRNA is responsible for M-mediated IFN-β induction that is preferentially associated with the activation of the Toll-like receptor (TLR adaptor proteins MyD88, TIRAP, and TICAM2 but not the RIG-I signaling cascade. Blocking the secretion of M protein by brefeldin A (BFA failed to reverse the M-mediated IFN-β induction. The antagonist of both TLR2 and TLR4 did not impede M-mediated IFN-β induction, indicating that the driving force for the activation of IFN-β production was generated from inside the cells. Inhibition of TRAF3 expression by specific small interfering RNA (siRNA did not prevent M-mediated IFN-β induction. SARS-CoV pseudovirus could induce IFN-β production in an M rather than M(V68A dependent manner, since the valine-to-alanine alteration at residue 68 in M protein markedly inhibited IFN-β production. Overall, our study indicates for the first time that a pathogen-derived protein is able to function as a cytosolic PAMP to stimulate type I interferon production by activating a noncanonical TLR signaling cascade in a TRAF3-independent manner.

  14. The Orphan Nuclear Receptor TR4 Is a Vitamin A-activated Nuclear Receptor

    Energy Technology Data Exchange (ETDEWEB)

    Zhou, X. Edward; Suino-Powell, Kelly M.; Xu, Yong; Chan, Cee-Wah; Tanabe, Osamu; Kruse, Schoen W.; Reynolds, Ross; Engel, James Douglas; Xu, H. Eric (Michigan-Med); (Van Andel)

    2015-11-30

    Testicular receptors 2 and 4 (TR2/4) constitute a subgroup of orphan nuclear receptors that play important roles in spermatogenesis, lipid and lipoprotein regulation, and the development of the central nervous system. Currently, little is known about the structural features and the ligand regulation of these receptors. Here we report the crystal structure of the ligand-free TR4 ligand binding domain, which reveals an autorepressed conformation. The ligand binding pocket of TR4 is filled by the C-terminal half of helix 10, and the cofactor binding site is occupied by the AF-2 helix, thus preventing ligand-independent activation of the receptor. However, TR4 exhibits constitutive transcriptional activity on multiple promoters, which can be further potentiated by nuclear receptor coactivators. Mutations designed to disrupt cofactor binding, dimerization, or ligand binding substantially reduce the transcriptional activity of this receptor. Importantly, both retinol and retinoic acid are able to promote TR4 to recruit coactivators and to activate a TR4-regulated reporter. These findings demonstrate that TR4 is a ligand-regulated nuclear receptor and suggest that retinoids might have a much wider regulatory role via activation of orphan receptors such as TR4.

  15. CINPA1 Is an Inhibitor of Constitutive Androstane Receptor That Does Not Activate Pregnane X Receptor

    OpenAIRE

    Cherian, Milu T; Lin, Wenwei; Wu, Jing; Chen, Taosheng

    2015-01-01

    Constitutive androstane receptor (CAR) and pregnane X receptor (PXR) are xenobiotic sensors that enhance the detoxification and elimination of xenobiotics and endobiotics by modulating the expression of genes encoding drug-metabolizing enzymes and transporters. Elevated levels of drug-metabolizing enzymes and efflux transporters, resulting from CAR activation in various cancers, promote the elimination of chemotherapeutic agents, leading to reduced therapeutic effectiveness and acquired drug ...

  16. Hepatitis B virus X protein promotes interleukin-7 receptor expression via NF-κB and Notch1 pathway to facilitate proliferation and migration of hepatitis B virus-related hepatoma cells

    Directory of Open Access Journals (Sweden)

    Fanyun Kong

    2016-11-01

    Full Text Available Abstract Background Interleukin-7 receptor (IL-7R is involved in the abnormal function of solid tumors, but the role and regulatory mechanisms of IL-7R in HBV-related hepatocellular carcinoma (HCC are still unclear. Methods Gene and protein expression levels of IL-7R were examined in hepatoma cells transfected with hepatitis B virus (HBV plasmids and in hepatoma cells transfected with the multifunctional nonstructural protein X (HBX. The expression of HBX and IL-7R was measured by immunohistochemical analysis in HBV-related HCC tissues. The role of NF-κB and Notch1 pathways in HBX-mediated expression of IL-7R in hepatoma cells was examined. Activation of IL-7R downstream of intracellular signaling proteins AKT, JNK, STAT5, and the associated molecules CyclinD1 and matrix metalloproteinase-9 (MMP-9, was assessed in HBX-positive cells with or without treatment with IL-7R short hairpin RNA (shRNA. Additionally, the role of IL-7R in HBX-mediated proliferation and migration of hepatoma cells was investigated. Results The expression of IL-7R was increased in hepatoma cells transfected with HBV plasmids; HBX was responsible for the HBV-mediated upregulation of IL-7R. Compared to adjacent tissues, the expression of HBX and IL-7R was increased in HBV-related HCC tissues. Additionally, the relative expression levels of HBX were associated with IL-7R in HBV-related HCC tissues. The activation of NF-κB pathways and expression of Notch1 were increased in hepatoma cells transfected with HBX, and inhibition of NF-κB and Notch1 pathways significantly decreased HBX-mediated expression of IL-7R. The activation of AKT and JNK and the expression of CyclinD1 and MMP-9 were increased in HBX-positive cells. When cells were treated with IL-7R shRNA, the activation of AKT and JNK, as well as the expression of CyclinD1 and MMP-9, were significantly inhibited. Additionally, IL-7R was responsible for HBX-induced proliferation and migration ability of hepatoma cells

  17. Ghrelin receptor controls obesity by fat burning

    Science.gov (United States)

    Emerging evidence show that brown fat in the body produces heat to burn energy, thus prompting weight loss. Ghrelin is the only known hormone which increases appetite and promotes weight gain. We have reported that mice that lack the receptor which mediates the functions of ghrelin are lean. Our fu...

  18. Peroxisome Proliferator-Activated Receptor Gamma Promotes Mesenchymal Stem Cells to Express Connexin43 via the Inhibition of TGF-β1/Smads Signaling in a Rat Model of Myocardial Infarction.

    Science.gov (United States)

    Hou, Jingying; Wang, Lingyun; Hou, Jinghui; Guo, Tianzhu; Xing, Yue; Zheng, Shaoxin; Zhou, Changqing; Huang, Hui; Long, Huibao; Zhong, Tingting; Wu, Quanhua; Wang, Jingfeng; Wang, Tong

    2015-12-01

    In this study, we hypothesized that activation of PPAR-γ enhanced MSCs survival and their therapeutic efficacy via upregulating the expression of Cx43. MI was induced in 50 male Sprague-Dawley rats. The rats were randomized into five groups: MI group and four intervention groups, including the MSCs group, combined therapy group (MSCs+ pioglitazone), pioglitazone group and PBS group. Two weeks later, 5 × 10(6) MSCs labeled with PKH26 in PBS were injected into the infarct anterior ventricular free wall in the MSCs and combined therapy groups, and PBS alone was injected into the infarct anterior ventricular free wall in the PBS group. Pioglitazone (3 mg/kg/day) was given to the combined therapy and pioglitazone groups by oral gavage at the same time for another 2 weeks. Myocardial function and relevant signaling molecules involved were all examined thereafter. Heart function was enhanced after MSCs treatment for 2 weeks post MI. A significant improvement of heart function was observed in the combined therapy group in contrast to the other three intervention groups. Compared with the MSCs group, there was a higher level of PPAR-γ in the combined therapy group; Cx43 was remarkably increased in different regions of the left ventricle; TGF-β1 was decreased in the infarct zone and border zone. To the downstream signaling molecules, mothers against Smad proteins including Smad2 and Smad3 presented a synchronized alteration with TGF-β1; no differences of the expressions of ERK1/2 and p38 could be discovered in the left ventricular cardiac tissue. MSCs transplantation combined with pioglitazone administration improved cardiac function more effectively after MI. Activation of PPAR-γ could promote MSCs to express Cx43. Inhibition of TGF-β1/Smads signaling pathway might be involved in the process.

  19. Perceptions of health promoters about health promotion ...

    African Journals Online (AJOL)

    2013-02-11

    Feb 11, 2013 ... Original Research http://www.hsag.co.za doi:10.4102/hsag.v18i1.648. Perceptions of health promoters about health promotion programmes for ... Providing health promotion in the communities is one of the many strategies that were introduced ... will therefore assist in improving and developing health.

  20. Muscarinic Receptor Signaling in Colon Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Rosenvinge, Erik C. von, E-mail: evonrose@medicine.umaryland.edu; Raufman, Jean-Pierre [University of Maryland School of Medicine, Division of Gastroenterology & Hepatology, 22 S. Greene Street, N3W62, Baltimore, MD 21201 (United States); Department of Veterans Affairs, VA Maryland Health Care System, 10 North Greene Street, Baltimore, MD 21201 (United States)

    2011-03-02

    According to the adenoma-carcinoma sequence, colon cancer results from accumulating somatic gene mutations; environmental growth factors accelerate and augment this process. For example, diets rich in meat and fat increase fecal bile acids and colon cancer risk. In rodent cancer models, increased fecal bile acids promote colon dysplasia. Conversely, in rodents and in persons with inflammatory bowel disease, low-dose ursodeoxycholic acid treatment alters fecal bile acid composition and attenuates colon neoplasia. In the course of elucidating the mechanism underlying these actions, we discovered that bile acids interact functionally with intestinal muscarinic receptors. The present communication reviews muscarinic receptor expression in normal and neoplastic colon epithelium, the role of autocrine signaling following synthesis and release of acetylcholine from colon cancer cells, post-muscarinic receptor signaling including the role of transactivation of epidermal growth factor receptors and activation of the ERK and PI3K/AKT signaling pathways, the structural biology and metabolism of bile acids and evidence for functional interaction of bile acids with muscarinic receptors on human colon cancer cells. In murine colon cancer models, deficiency of subtype 3 muscarinic receptors attenuates intestinal neoplasia; a proof-of-concept supporting muscarinic receptor signaling as a therapeutic target for colon cancer.

  1. Muscarinic Receptor Signaling in Colon Cancer

    International Nuclear Information System (INIS)

    Rosenvinge, Erik C. von; Raufman, Jean-Pierre

    2011-01-01

    According to the adenoma-carcinoma sequence, colon cancer results from accumulating somatic gene mutations; environmental growth factors accelerate and augment this process. For example, diets rich in meat and fat increase fecal bile acids and colon cancer risk. In rodent cancer models, increased fecal bile acids promote colon dysplasia. Conversely, in rodents and in persons with inflammatory bowel disease, low-dose ursodeoxycholic acid treatment alters fecal bile acid composition and attenuates colon neoplasia. In the course of elucidating the mechanism underlying these actions, we discovered that bile acids interact functionally with intestinal muscarinic receptors. The present communication reviews muscarinic receptor expression in normal and neoplastic colon epithelium, the role of autocrine signaling following synthesis and release of acetylcholine from colon cancer cells, post-muscarinic receptor signaling including the role of transactivation of epidermal growth factor receptors and activation of the ERK and PI3K/AKT signaling pathways, the structural biology and metabolism of bile acids and evidence for functional interaction of bile acids with muscarinic receptors on human colon cancer cells. In murine colon cancer models, deficiency of subtype 3 muscarinic receptors attenuates intestinal neoplasia; a proof-of-concept supporting muscarinic receptor signaling as a therapeutic target for colon cancer

  2. Muscarinic Receptor Signaling in Colon Cancer

    Directory of Open Access Journals (Sweden)

    Jean-Pierre Raufman

    2011-03-01

    Full Text Available According to the adenoma-carcinoma sequence, colon cancer results from accumulating somatic gene mutations; environmental growth factors accelerate and augment this process. For example, diets rich in meat and fat increase fecal bile acids and colon cancer risk. In rodent cancer models, increased fecal bile acids promote colon dysplasia. Conversely, in rodents and in persons with inflammatory bowel disease, low-dose ursodeoxycholic acid treatment alters fecal bile acid composition and attenuates colon neoplasia. In the course of elucidating the mechanism underlying these actions, we discovered that bile acids interact functionally with intestinal muscarinic receptors. The present communication reviews muscarinic receptor expression in normal and neoplastic colon epithelium, the role of autocrine signaling following synthesis and release of acetylcholine from colon cancer cells, post-muscarinic receptor signaling including the role of transactivation of epidermal growth factor receptors and activation of the ERK and PI3K/AKT signaling pathways, the structural biology and metabolism of bile acids and evidence for functional interaction of bile acids with muscarinic receptors on human colon cancer cells. In murine colon cancer models, deficiency of subtype 3 muscarinic receptors attenuates intestinal neoplasia; a proof-of-concept supporting muscarinic receptor signaling as a therapeutic target for colon cancer.

  3. In Silico Investigation of the Neurotensin Receptor 1 Binding Site

    DEFF Research Database (Denmark)

    Lückmann, Michael; Holst, Birgitte; Schwartz, Thue W.

    2016-01-01

    structure of NTSR1 in complex with NTS8-13 has been detd., providing novel insights into peptide ligand recognition by 7TM receptors. SR48692, a potent and selective small mol. antagonist has previously been used extensively as a tool compd. to study NTSR1 receptor signaling properties. To investigate......The neurotensin receptor 1 (NTSR1) belongs to the family of 7TM, G protein-coupled receptors, and is activated by the 13-amino-acid peptide neurotensin (NTS) that has been shown to play important roles in neurol. disorders and the promotion of cancer cells. Recently, a high-resoln. x-ray crystal...

  4. AMPA receptor pHluorin-GluA2 reports NMDA receptor-induced intracellular acidification in hippocampal neurons

    DEFF Research Database (Denmark)

    Rathje, Mette; Fang, Huaqiang; Bachman, Julia L

    2013-01-01

    NMDA receptor activation promotes endocytosis of AMPA receptors, which is an important mechanism underlying long-term synaptic depression. The pH-sensitive GFP variant pHluorin fused to the N terminus of GluA2 (pH-GluA2) has been used to assay NMDA-mediated AMPA receptor endocytosis and recycling...... recovery was eliminated in the presence of the NHE1 inhibitor zoniporide. Our results indicate that the pH-GluA2 recycling assay is an unreliable assay for studying AMPA receptor trafficking and also suggest a role for PICK1 in regulating intracellular pH via modulation of NHE activity....

  5. Lipophorin Receptor: The Insect Lipoprotein Receptor

    Indian Academy of Sciences (India)

    IAS Admin

    physiology and develop- mental biology of silkworms, and use of silk in industrial applications. The low-density lipoprotein receptor (LDLR), one of the best characterized cell-surface receptors, mediates cholesterol ho- meostasis and other functions in mammals. The members of the LDLR superfamily are structurally related ...

  6. Lipophorin Receptor: The Insect Lipoprotein Receptor

    Indian Academy of Sciences (India)

    Permanent link: http://www.ias.ac.in/article/fulltext/reso/018/08/0748-0755. Keywords. Low-density lipoprotein receptor; lipophorin; lipophorin receptor; insects. Author Affiliations. G Ravikumar1 N B Vijayaprakash1. Seri-biotech Research Laboratory Central Silk Board Kodathi, Carmelaram Post Bangalore 560 035, India.

  7. What Is a Promotion?

    Science.gov (United States)

    Pergamit, Michael R.; Veum, Jonathan R.

    1999-01-01

    For a sample of young workers, "promotion" involved no change in position or duties; promotion was more likely for males than females and Whites than Blacks or Hispanics. Company training and prior promotions were important predictors. Promotion did not appear to have a direct impact on job satisfaction. (SK)

  8. Acetylcholine receptor antibody

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/003576.htm Acetylcholine receptor antibody To use the sharing features on this page, please enable JavaScript. Acetylcholine receptor antibody is a protein found in the blood ...

  9. Androgen receptor abnormalities

    NARCIS (Netherlands)

    A.O. Brinkmann (Albert); G.G.J.M. Kuiper (George); C. Ris-Stalpers (Carolyn); H.C.J. van Rooij (Henri); G. Romalo (G.); G. Trifiro (Gianluca); E. Mulder (Eppo); L. Pinsky (L.); H.U. Schweikert (H.); J. Trapman (Jan)

    1991-01-01

    markdownabstract__Abstract__ The human androgen receptor is a member of the superfamily of steroid hormone receptors. Proper functioning of this protein is a prerequisite for normal male sexual differentiation and development. The cloning of the human androgen receptor cDNA and the elucidation of

  10. Androgen receptor abnormalities

    NARCIS (Netherlands)

    Brinkmann, A. O.; Kuiper, G. G.; Ris-Stalpers, C.; van Rooij, H. C.; Romalo, G.; Trifiro, M.; Mulder, E.; Pinsky, L.; Schweikert, H. U.; Trapman, J.

    1991-01-01

    The human androgen receptor is a member of the superfamily of steroid hormone receptors. Proper functioning of this protein is a prerequisite for normal male sexual differentiation and development. The cloning of the human androgen receptor cDNA and the elucidation of the genomic organization of the

  11. Neuropeptide y promotes neurogenesis in murine subventricular zone

    DEFF Research Database (Denmark)

    Agasse, Fabienne; Bernardino, Liliana; Kristiansen, Heidi

    2008-01-01

    Stem cells of the subventricular zone (SVZ) represent a reliable source of neurons for cell replacement. Neuropeptide Y (NPY) promotes neurogenesis in the hippocampal subgranular layer and the olfactory epithelium and may be useful for the stimulation of SVZ dynamic in brain repair purposes. We...... describe that NPY promotes SVZ neurogenesis. NPY (1 microM) treatments increased proliferation at 48 hours and neuronal differentiation at 7 days in SVZ cell cultures. NPY proneurogenic properties are mediated via the Y1 receptor. Accordingly, Y1 receptor is a major active NPY receptor in the mouse SVZ......-Jun-NH(2)-terminal kinase signal in growing axons, consistent with axonogenesis. NPY, as a promoter of SVZ neurogenesis, is a crucial factor for future development of cell-based brain therapy. Disclosure of potential conflicts of interest is found at the end of this article....

  12. Functional reconstitution of the glycine receptor

    International Nuclear Information System (INIS)

    Garcia-Calvo, M.; Ruiz-Gomez, A.; Vazquez, J.; Morato, E.; Valdivieso, F.; Mayor, F. Jr.

    1989-01-01

    The functional reconstitution of the chloride channel coupled glycine receptor is described. Glycine receptors were purified from the cholate extract of rat spinal cord membranes by affinity chromatography and incorporated into phospholipid vesicles by the addition of phosphatidylcholine and removal of detergent by gel filtration. The reconstituted vesicles showed the same polypeptide composition as the purified receptor. The pharmacological characteristics of the glycine receptor were also preserved in the proteoliposomes, as demonstrated by the displacement of [ 3 H]strychnine binding by several glycinergic ligands and by photoaffinity labeling experiments. In order to observe functional responses (i.e., specific agonist-induced anion translocation), the authors have developed an assay based on the fluorescence quenching of an anion-sensitive entrapped probe, SPQ [6-methoxy-N-(3-sulfopropyl)quinolinium]. Reconstituted vesicles were loaded with the fluorescent probe during a freeze-thaw-sonication cycle in the presence of added liposomes containing cholesterol. In such a reconstituted system, glycine receptor agonists are able to increase the rate of anion influx into the vesicles. The action of agonists is blocked by the simultaneous presence of strychnine or other glycine antagonists. The results show that the purified 48,000- and 58,000-dalton polypeptides reconstituted into phospholipid vesicles can bind ligands and promote specific ion translocation in a way similar to the glycine receptor in its native environment

  13. Development of selective androgen receptor modulators (SARMs).

    Science.gov (United States)

    Narayanan, Ramesh; Coss, Christopher C; Dalton, James T

    2017-06-15

    The Androgen Receptor (AR), a member of the steroid hormone receptor family, plays important roles in the physiology and pathology of diverse tissues. AR ligands, which include circulating testosterone and locally synthesized dihydrotestosterone, bind to and activate the AR to elicit their effects. Ubiquitous expression of the AR, metabolism and cross reactivity with other receptors limit broad therapeutic utilization of steroidal androgens. However, the discovery of selective androgen receptor modulators (SARMs) and other tissue-selective nuclear hormone receptor modulators that activate their cognate receptors in a tissue-selective manner provides an opportunity to promote the beneficial effects of androgens and other hormones in target tissues with greatly reduced unwanted side-effects. In the last two decades, significant resources have been dedicated to the discovery and biological characterization of SARMs in an effort to harness the untapped potential of the AR. SARMs have been proposed as treatments of choice for various diseases, including muscle-wasting, breast cancer, and osteoporosis. This review provides insight into the evolution of SARMs from proof-of-concept agents to the cusp of therapeutic use in less than two decades, while covering contemporary views of their mechanisms of action and therapeutic benefits. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Development of prolactin receptor antagonists with reduced pH-dependence of receptor binding

    DEFF Research Database (Denmark)

    Hansen, Mathilde Johanne Kaas; Olsen, Johan Gotthardt; Bernichtein, Sophie

    2011-01-01

    Abstract The cytokine hormone prolactin has a vast number of diverse functions. Unfortunately, it also exhibits tumor growth promoting properties, which makes the development of prolactin receptor antagonists a priority. Prolactin binds to its cognate receptor with much lower affinity at low p....... From evaluation of known molecular structures of human prolactin, of the prolactin receptor and of different complexes of the two, three histidine residues in the hormone-receptor binding site 1 were selected for mutational studies. We analyzed 10 variants by circular dichroism spectroscopy, affinity...... antagonists were developed earlier and the histidine mutations were introduced within such background. The antagonistic properties were maintained and the high affinity at low pH conserved. The implications of these findings may open new areas of research in the field of prolactin cancer biology. Copyright...

  15. Microvesicle transfer of kinin B1-receptors is a novel inflammatory mechanism in vasculitis.

    Science.gov (United States)

    Kahn, Robin; Mossberg, Maria; Ståhl, Anne-Lie; Johansson, Karl; Lopatko Lindman, Ingrid; Heijl, Caroline; Segelmark, Mårten; Mörgelin, Matthias; Leeb-Lundberg, L M Fredrik; Karpman, Diana

    2017-01-01

    During vasculitis, activation of the kinin system induces inflammation, whereby the kinin B1-receptor is expressed and activated after ligand binding. Additionally, activated blood cells release microvesicles into the circulation. Here we determined whether leukocyte-derived microvesicles bear B1-kinin receptors during vasculitis, and if microvesicles transfer functional B1-receptors to recipient cells, thus promoting inflammation. By flow cytometry, plasma from patients with vasculitis were found to contain high levels of leukocyte-derived microvesicles bearing B1-receptors. Importantly, renal biopsies from two patients with vasculitis showed leukocyte-derived microvesicles bearing B1-receptors docking on glomerular endothelial cells providing in vivo relevance. Microvesicles derived from B1-receptor-transfected human embryonic kidney cells transferred B1-receptors to wild-type human embryonic kidney cells, lacking the receptor, and to glomerular endothelial cells. The transferred B1-receptors induced calcium influx after B1-receptor agonist stimulation: a response abrogated by a specific B1-receptor antagonist. Microvesicles derived from neutrophils also transferred B1-receptors to wild-type human embryonic kidney cells and induced calcium influx after stimulation. Thus, we found a novel mechanism by which microvesicles transfer functional receptors and promote kinin-associated inflammation. Copyright © 2016 International Society of Nephrology. Published by Elsevier Inc. All rights reserved.

  16. Recruitment of activation receptors at inhibitory NK cell immune synapses.

    Directory of Open Access Journals (Sweden)

    Nicolas Schleinitz

    2008-09-01

    Full Text Available Natural killer (NK cell activation receptors accumulate by an actin-dependent process at cytotoxic immune synapses where they provide synergistic signals that trigger NK cell effector functions. In contrast, NK cell inhibitory receptors, including members of the MHC class I-specific killer cell Ig-like receptor (KIR family, accumulate at inhibitory immune synapses, block actin dynamics, and prevent actin-dependent phosphorylation of activation receptors. Therefore, one would predict inhibition of actin-dependent accumulation of activation receptors when inhibitory receptors are engaged. By confocal imaging of primary human NK cells in contact with target cells expressing physiological ligands of NK cell receptors, we show here that this prediction is incorrect. Target cells included a human cell line and transfected Drosophila insect cells that expressed ligands of NK cell activation receptors in combination with an MHC class I ligand of inhibitory KIR. The two NK cell activation receptors CD2 and 2B4 accumulated and co-localized with KIR at inhibitory immune synapses. In fact, KIR promoted CD2 and 2B4 clustering, as CD2 and 2B4 accumulated more efficiently at inhibitory synapses. In contrast, accumulation of KIR and of activation receptors at inhibitory synapses correlated with reduced density of the integrin LFA-1. These results imply that inhibitory KIR does not prevent CD2 and 2B4 signaling by blocking their accumulation at NK cell immune synapses, but by blocking their ability to signal within inhibitory synapses.

  17. C-type lectin receptors and RIG-I-like receptors: new points on the oncogenomics map

    Directory of Open Access Journals (Sweden)

    Yuzhalin AE

    2012-02-01

    Full Text Available Anton G Kutikhin, Arseniy E YuzhalinDepartment of Epidemiology, Kemerovo State Medical Academy, Kemerovo, Russian FederationAbstract: The group of pattern recognition receptors includes families of Toll-like receptors, NOD-like receptors, C-type lectin receptors, and RIG-I-like receptors. They are key sensors for a number of infectious agents, some of which are oncogenic, and they launch an immune response against them, normally promoting their eradication. Inherited variations in genes encoding these receptors and proteins and their signaling pathways may affect their function, possibly modulating cancer risk and features of cancer progression. There are numerous studies investigating the association of single nucleotide polymorphisms within or near genes encoding Toll-like receptors and NOD-like receptors, cancer risk, and features of cancer progression. However, there is an almost total absence of articles analyzing the correlation between polymorphisms of genes encoding C-type lectin receptors and RIG-I-like receptors and cancer risk or progression. Nevertheless, there is some evidence supporting the hypothesis that inherited C-type lectin receptor and RIG-I-like receptor variants can be associated with increased cancer risk. Certain C-type lectin receptors and RIG-I-like receptors recognize pathogen-associated molecular patterns of potentially oncogenic infectious agents, and certain polymorphisms of genes encoding C-type lectin receptors and RIG-I-like receptors may have functional consequences at the molecular level that can lead to association of such single nucleotide polymorphisms with risk or progression of some diseases that may modulate cancer risk, so these gene polymorphisms may affect cancer risk indirectly. Polymorphisms of genes encoding C-type lectin receptors and RIG-I-like receptors thereby may be correlated with a risk of lung, oral, esophageal, gastric, colorectal, and liver cancer, as well as nasopharyngeal carcinoma

  18. Promoting preschool reading

    OpenAIRE

    Istenič, Vesna

    2013-01-01

    The thesis titled Promoting preschool reading consists of a theoretiral and an empirical part. In the theoretical part I wrote about reading, the importance of reading, types of reading, about reading motivation, promoting reading motivation, internal and external motivation, influence of reading motivation on the child's reading activity, reading and familial literacy, the role of adults in promotion reading literacy, reading to a child and promoting reading in pre-school years, where I ...

  19. Prolactin receptor and signal transduction to milk protein genes

    Energy Technology Data Exchange (ETDEWEB)

    Djiane, J.; Daniel, N.; Bignon, C. [Unite d`Endocrinologie Moleculaire, Jouy en Josas (France)] [and others

    1994-06-01

    After cloning of the mammary gland prolactin (PRL) receptor cDNA, a functional assay was established using co-transfection of PRL receptor cDNA together with a milk protein promoter/chloramphenicol acetyl transferase (CAT) construct in Chinese hamster ovary (CHO) cells. Different mutants of the PRL receptor were tested in this CAT assay to delimit the domains in the receptor necessary for signal transduction to milk protein genes. In CHO cells stably transfected with PRL receptor cDNA, high numbers of PRL receptor are expressed. By metabolic labeling and immunoprecipitation, expressed PRL receptor was identified as a single species of 100 kDa. Using these cells, we analyzed the effects of PRL on intracellular free Ca{sup ++} concentration. PRL stimulates Ca{sup ++} entry and induces secondary Ca{sup ++} mobilization. The entry of Ca{sup ++} is a result of an increase in K{sup +} conductance that hyperpolarizes the membranes. We have also analyzed tyrosine phosphorylation induced by PRL. In CHO cells stably transfected with PRL receptor cDNA, PRL induced a very rapid and transient tyrosine phosphorylation of a 100-kDa protein which is most probably the PRL receptor. The same finding was obtained in mammary membranes after PRL injection to lactating rabbits. Whereas tyrosine kinase inhibitors genistein and lavendustin were without effect, PRL stimulation of milk protein gene promoters was partially inhibited by 2 {mu}M herbimycin in CHO cells co-transfected with PRL receptor cDNA and the {Beta} lactoglobulin CAT construct. Taken together these observations indicate that the cytoplasmic domain of the PRL receptor interacts with one or several tyrosine kinases, which may represent early postreceptor events necessary for PRL signal transduction to milk protein genes. 14 refs., 4 figs.

  20. GABA receptor imaging

    Energy Technology Data Exchange (ETDEWEB)

    Lee, Jong Doo [Yonsei University College of Medicine, Seoul (Korea, Republic of)

    2007-04-15

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA{sub A}-receptor that allows chloride to pass through a ligand gated ion channel and GABA{sub B}-receptor that uses G-proteins for signaling. The GABA{sub A}-receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA{sub A}-receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with {sup 11}C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, {sup 18}F-fluoroflumazenil (FFMZ) has been developed to overcome {sup 11}C's short half-life. {sup 18}F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1{sup 1}C-FMZ PET instead of {sup 18}F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA{sub A} receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas.

  1. GABA receptor imaging

    International Nuclear Information System (INIS)

    Lee, Jong Doo

    2007-01-01

    GABA is primary an inhibitory neurotransmitter that is localized in inhibitory interneurons. GABA is released from presynaptic terminals and functions by binding to GABA receptors. There are two types of GABA receptors, GABA A -receptor that allows chloride to pass through a ligand gated ion channel and GABA B -receptor that uses G-proteins for signaling. The GABA A -receptor has a GABA binding site as well as a benzodiazepine binding sites, which modulate GABA A -receptor function. Benzodiazepine GABAA receptor imaging can be accomplished by radiolabeling derivates that activates benzodiazepine binding sites. There has been much research on flumazenil (FMZ) labeled with 11 C-FMZ, a benzodiazepine derivate that is a selective, reversible antagonist to GABAA receptors. Recently, 18 F-fluoroflumazenil (FFMZ) has been developed to overcome 11 C's short half-life. 18 F-FFMZ shows high selective affinity and good pharmacodynamics, and is a promising PET agent with better central benzodiazepine receptor imaging capabilities. In an epileptic focus, because the GABA/benzodiazepine receptor amount is decreased, using '1 1 C-FMZ PET instead of 18 F-FDG, PET, restrict the foci better and may also help find lesions better than high resolution MR. GABA A receptors are widely distributed in the cerebral cortex, and can be used as an viable neuronal marker. Therefore it can be used as a neuronal cell viability marker in cerebral ischemia. Also, GABA-receptors decrease in areas where neuronal plasticity develops, therefore, GABA imaging can be used to evaluate plasticity. Besides these usages, GABA receptors are related with psychological diseases, especially depression and schizophrenia as well as cerebral palsy, a motor-related disorder, so further in-depth studies are needed for these areas

  2. Biological activity of cloned mammary tumor virus DNA fragments that bind purified glucocorticoid receptor protein in vitro

    International Nuclear Information System (INIS)

    Yamamoto, K.R.; Payvar, F.; Firestone, G.L.; Maler, B.A.; Wrange, O.; Carlstedt-Duke, J.; Gustafsson, J.A.; Chandler, V.L.; Karolinska Institutet, Stockholm, Sweden)

    1983-01-01

    To test whether high-affinity receptor:DNA interactions can be correlated with receptor effects on promoter function in vivo, we have mapped in greater detail the receptor-binding regions on murine mammary tumor virus DNA, using both nitrocellulose-filter binding and electron microscopy. Recombinant plasmids bearing these receptor-binding domains have been transfected into cultured cells, and the expression of the plasmid sequences has been monitored for hormonal regulation. The results are considered in terms of a speculative proposal that the glucocorticoid receptor may effect changes in promoter activity via specific alteration of chromatin and/or DNA structure. 37 references, 6 figures, 2 tables

  3. Developing a Promotional Video

    Science.gov (United States)

    Epley, Hannah K.

    2014-01-01

    There is a need for Extension professionals to show clientele the benefits of their program. This article shares how promotional videos are one way of reaching audiences online. An example is given on how a promotional video has been used and developed using iMovie software. Tips are offered for how professionals can create a promotional video and…

  4. Dengue virus receptor

    OpenAIRE

    Hidari, Kazuya I.P.J.; Suzuki, Takashi

    2011-01-01

    Dengue virus is an arthropod-borne virus transmitted by Aedes mosquitoes. Dengue virus causes fever and hemorrhagic disorders in humans and non-human primates. Direct interaction of the virus introduced by a mosquito bite with host receptor molecule(s) is crucial for virus propagation and the pathological progression of dengue diseases. Therefore, elucidation of the molecular mechanisms underlying the interaction between dengue virus and its receptor(s) in both humans and mosquitoes is essent...

  5. Therapeutic androgen receptor ligands

    Science.gov (United States)

    Allan, George F.; Sui, Zhihua

    2003-01-01

    In the past several years, the concept of tissue-selective nuclear receptor ligands has emerged. This concept has come to fruition with estrogens, with the successful marketing of drugs such as raloxifene. The discovery of raloxifene and other selective estrogen receptor modulators (SERMs) has raised the possibility of generating selective compounds for other pathways, including androgens (that is, selective androgen receptor modulators, or SARMs). PMID:16604181

  6. Topical administration of adrenergic receptor pharmaceutics and nerve growth factor

    Directory of Open Access Journals (Sweden)

    Jena J Steinle

    2010-06-01

    Full Text Available Jena J SteinleDepartments of Ophthalmology and Anatomy and Neurobiology, Hamilton Eye Institute, University of Tennessee Health Science Center, Memphis, TN 38163, USAAbstract: Topical application of nerve growth factor (NGF and adrenergic receptor pharmaceutics are currently in use for corneal ulcers and glaucoma. A recent interest in the neuroprotective abilities of NGF has led to a renewed interest in NGF as a therapeutic for retinal and choroidal diseases. NGF can promote cell proliferation through actions of the TrkA receptor or promote apoptosis through receptor p75NTR. This understanding has led to novel interest in the role of NGF for diseases of the posterior eye. The role of β-adrenergic receptor agonists and antagonists for treatments of glaucoma, diabetic retinopathy, and their potential mechanisms of action, are still under investigation. This review discusses the current knowledge and applications of topical NGF and adrenergic receptor drugs for ocular disease.Keywords: NGF, β-adrenergic receptor agents, α-adrenergic receptor agents, retina, cornea, glaucoma

  7. Muscle Plasticity and β2-Adrenergic Receptors: Adaptive Responses of β2-Adrenergic Receptor Expression to Muscle Hypertrophy and Atrophy

    Directory of Open Access Journals (Sweden)

    Shogo Sato

    2011-01-01

    Full Text Available We discuss the functional roles of β2-adrenergic receptors in skeletal muscle hypertrophy and atrophy as well as the adaptive responses of β2-adrenergic receptor expression to anabolic and catabolic conditions. β2-Adrenergic receptor stimulation using anabolic drugs increases muscle mass by promoting muscle protein synthesis and/or attenuating protein degradation. These effects are prevented by the downregulation of the receptor. Endurance training improves oxidative performance partly by increasing β2-adrenergic receptor density in exercise-recruited slow-twitch muscles. However, excessive stimulation of β2-adrenergic receptors negates their beneficial effects. Although the preventive effects of β2-adrenergic receptor stimulation on atrophy induced by muscle disuse and catabolic hormones or drugs are observed, these catabolic conditions decrease β2-adrenergic receptor expression in slow-twitch muscles. These findings present evidence against the use of β2-adrenergic agonists in therapy for muscle wasting and weakness. Thus, β2-adrenergic receptors in the skeletal muscles play an important physiological role in the regulation of protein and energy balance.

  8. What do health-promoting schools promote?

    DEFF Research Database (Denmark)

    Simovska, Venka

    2012-01-01

    review process, nine submissions were accepted for publication. Five of these are selected to be published in this issue and the rest will be published in a future issue of the journal. Findings – The five articles in this issue take a comprehensive approach to health promotion in schools and reflect......Purpose – The editorial aims to provide a brief overview of the individual contributions to the special issue, and a commentary positioning the contributions within research relating to the health-promoting schools initiative in Europe. Design/methodology/approach – The members of the Schools...... for Health in Europe Research Group were invited to submit their work addressing processes and outcomes in school health promotion to this special issue of Health Education. Additionally, an open call for papers was published on the Health Education web site. Following the traditional double blind peer...

  9. AMPA receptor pHluorin-GluA2 reports NMDA receptor-induced intracellular acidification in hippocampal neurons

    OpenAIRE

    Rathje, Mette; Fang, Huaqiang; Bachman, Julia L.; Anggono, Victor; Gether, Ulrik; Huganir, Richard L.; Madsen, Kenneth L.

    2013-01-01

    NMDA receptor activation promotes endocytosis of AMPA receptors, which is an important mechanism underlying long-term synaptic depression. The pH-sensitive GFP variant pHluorin fused to the N terminus of GluA2 (pH-GluA2) has been used to assay NMDA-mediated AMPA receptor endocytosis and recycling. Here, we demonstrate that in somatic and dendritic regions of hippocampal neurons a large fraction of the fluorescent signal originates from intracellular pH-GluA2, and that the decline in fluoresce...

  10. SPORT PROMOTION STRATEGIES

    Directory of Open Access Journals (Sweden)

    Alexandru Lucian MIHAI

    2013-10-01

    Full Text Available In sport marketing, the word promotion covers a range of interrelated activities. All of these activities are designed to attract attention, stimulate the interest and awareness of consumers, and of course, encourage them to purchase a sport product. Promotion is about communicating with and educating consumers. The purpose of a sport promotional strategy is to build brand loyalty and product credibility, develop image, and position the brand. A promotional strategy is similar to a marketing strategy, but the promotional strategy seeks short-term objectives, both direct and indirect. Promotional objectives usually include increased sales, stimulate impulse buying, raise customer traffic, and present and reinforce image. It also provides information about products and services, publicizes new stores or websites, and creates and enhances customer satisfaction.

  11. AMPA receptor ligands

    DEFF Research Database (Denmark)

    Strømgaard, Kristian; Mellor, Ian

    2004-01-01

    Alpha-amino-3-hydroxy-5-methyl-4-isoxazole propionic acid (AMPA) receptors (AMPAR), subtype of the ionotropic glutamate receptors (IGRs), mediate fast synaptic transmission in the central nervous system (CNS), and are involved in many neurological disorders, as well as being a key player...

  12. Angiotensin type 2 receptors

    DEFF Research Database (Denmark)

    Sumners, Colin; de Kloet, Annette D; Krause, Eric G

    2015-01-01

    In most situations, the angiotensin AT2-receptor (AT2R) mediates physiological actions opposing those mediated by the AT1-receptor (AT1R), including a vasorelaxant effect. Nevertheless, experimental evidence vastly supports that systemic application of AT2R-agonists is blood pressure neutral...

  13. Glutamate receptor agonists

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Greenwood, Jeremy R; Bunch, Lennart

    2011-01-01

    The neurotransmitter (S)-glutamate [(S)-Glu] is responsible for most of the excitatory neurotransmission in the central nervous system. The effect of (S)-Glu is mediated by both ionotropic and metabotropic receptors. Glutamate receptor agonists are generally a-amino acids with one or more...... stereogenic centers due to strict requirements in the agonist binding pocket of the activated state of the receptor. By contrast, there are many examples of achiral competitive antagonists. The present review addresses how stereochemistry affects the activity of glutamate receptor ligands. The review focuses...... mainly on agonists and discusses stereochemical and conformational considerations as well as biostructural knowledge of the agonist binding pockets, which is useful in the design of glutamate receptor agonists. Examples are chosen to demonstrate how stereochemistry not only determines how the agonist...

  14. Association study of the platelet collagen receptor glycoprotein VI gene with rheumatoid arthritis

    NARCIS (Netherlands)

    Michou, L.; Cornelis, F.; Baron, M.; Bombardieri, S.; Balsa, A.; Westhovens, R.; Barrera, P.; Alves, H.; Radstake, T.R.D.J.; Migliorini, P.; Bardin, T.; Petit-Teixeira, E.; Boilard, E.

    2013-01-01

    OBJECTIVES: Beyond their role in haemostasis, platelets can actively contribute to immunity. The activation of the platelet collagen receptor glycoprotein VI (GPVI) promotes the release of small extracellular vesicles called microparticles. These microparticles are found in the joint bathing fluid

  15. Chronic regulation of colonic epithelial secretory function by activation of G protein-coupled receptors.

    LENUS (Irish Health Repository)

    Toumi, F

    2011-02-01

    Enteric neurotransmitters that act at G protein-coupled receptors (GPCRs) are well known to acutely promote epithelial Cl(-) and fluid secretion. Here we examined if acute GPCR activation might have more long-term consequences for epithelial secretory function.

  16. Health promotion in globalization

    Directory of Open Access Journals (Sweden)

    Álvaro Franco-Giraldo

    2012-10-01

    Full Text Available Objective: to unravel some theoretical and factual elements required to implement more effective health promotion strategies and practices in the field of health services whilst following the great challenges that globalization has imposed on the health systems, which are inevitably expressed in the local context (glocalization. Methodology: a narrative review taking into account the concepts of globalization and health promotion in relation to health determinants. The authors approach some courses of action and strategies for health promotion based on the social principles and universal values that guide health promotion, health service reorientation and primary healthcare, empowerment, social participation, and inter-sectoral and social mobilization. Discussion: the discussion focuses on the redirection of health promotion services in relation to the wave of health reforms that has spread throughout the world under the neoliberal rule. The author also discusses health promotion, its ineffectiveness, and the quest for renewal. Likewise, the author sets priorities for health promotion in relation to social determinants. Conclusion: the current global order, in terms of international relations, is not consistent with the ethical principles of health promotion. In this paper, the author advocates for the implementation of actions to change the social and physical life conditions of people based on changes in the use of power in society and the appropriate practice of politics in the context of globalization in order to achieve the effectiveness of the actions of health promotion.

  17. P2X receptors.

    Science.gov (United States)

    North, R Alan

    2016-08-05

    Extracellular adenosine 5'-triphosphate (ATP) activates cell surface P2X and P2Y receptors. P2X receptors are membrane ion channels preferably permeable to sodium, potassium and calcium that open within milliseconds of the binding of ATP. In molecular architecture, they form a unique structural family. The receptor is a trimer, the binding of ATP between subunits causes them to flex together within the ectodomain and separate in the membrane-spanning region so as to open a central channel. P2X receptors have a widespread tissue distribution. On some smooth muscle cells, P2X receptors mediate the fast excitatory junction potential that leads to depolarization and contraction. In the central nervous system, activation of P2X receptors allows calcium to enter neurons and this can evoke slower neuromodulatory responses such as the trafficking of receptors for the neurotransmitter glutamate. In primary afferent nerves, P2X receptors are critical for the initiation of action potentials when they respond to ATP released from sensory cells such as taste buds, chemoreceptors or urothelium. In immune cells, activation of P2X receptors triggers the release of pro-inflammatory cytokines such as interleukin 1β. The development of selective blockers of different P2X receptors has led to clinical trials of their effectiveness in the management of cough, pain, inflammation and certain neurodegenerative diseases.This article is part of the themed issue 'Evolution brings Ca(2+) and ATP together to control life and death'. © 2016 The Author(s).

  18. The Role of Prolactin Receptor in GH Signaling in Breast Cancer Cells

    OpenAIRE

    Xu, Jie; Sun, Dongmei; Jiang, Jing; Deng, Luqin; Zhang, Yue; Yu, Hao; Bahl, Deepti; Langenheim, John F.; Chen, Wen Y.; Fuchs, Serge Y.; Frank, Stuart J.

    2012-01-01

    GH and prolactin (PRL) are structurally related hormones that exert important effects in disparate target tissues. Their receptors (GHR and PRLR) reside in the cytokine receptor superfamily and share signaling pathways. In humans, GH binds both GHR and PRLR, whereas PRL binds only PRLR. Both hormones and their receptors may be relevant in certain human and rodent cancers, including breast cancer. GH and PRL promote signaling in human T47D breast cancer cells that express both GHR and PRLR. Fu...

  19. Receptor activity-independent recruitment of βarrestin2 reveals specific signalling modes

    Science.gov (United States)

    Terrillon, Sonia; Bouvier, Michel

    2004-01-01

    The roles of βarrestins in regulating G protein coupling and receptor endocytosis following agonist stimulation of G protein-coupled receptors are well characterised. However, their ability to act on their own as direct modulators or activators of signalling remains poorly characterised. Here, βarrestin2 intrinsic signalling properties were assessed by forcing the recruitment of this accessory protein to vasopressin V1a or V2 receptors independently of agonist-promoted activation of the receptors. Such induction of a stable interaction with βarrestin2 initiated receptor endocytosis leading to intracellular accumulation of the βarrestin/receptor complexes. Interestingly, βarrestin2 association to a single receptor protomer was sufficient to elicit receptor dimer internalisation. In addition to recapitulating βarrestin2 classical actions on receptor trafficking, the receptor activity-independent recruitment of βarrestin2 activated the extracellular signal-regulated kinases. In the latter case, recruitment to the receptor itself was not required since kinase activation could be mediated by βarrestin2 translocation to the plasma membrane in the absence of any interacting receptor. These data demonstrate that βarrestin2 can act as a ‘bonafide' signalling molecule even in the absence of activated receptor. PMID:15385966

  20. Epidermis-type lipoxygenase 3 regulates adipocyte differentiation and peroxisome proliferator-activated receptor gamma activity

    DEFF Research Database (Denmark)

    Hallenborg, Philip; Jørgensen, Claus; Petersen, Rasmus K

    2010-01-01

    The nuclear receptor peroxisome proliferator-activated receptor gamma (PPAR gamma) is essential for adipogenesis. Although several fatty acids and their derivatives are known to bind and activate PPAR gamma, the nature of the endogenous ligand(s) promoting the early stages of adipocyte differenti...

  1. Low density lipoprotein induces upregulation of vasoconstrictive endothelin type B receptor expression

    DEFF Research Database (Denmark)

    Xu, Cang-Bao; Zheng, Jian-Pu; Zhang, Wei

    2014-01-01

    Vasoconstrictive endothelin type B (ET(B)) receptors promote vasospasm and ischemic cerebro- and cardiovascular diseases. The present study was designed to examine if low density lipoprotein (LDL) induces upregulation of vasoconstrictive ET(B) receptor expression and if extracellular signal-regul...

  2. mTOR Is Essential for Corticosteroid Effects on Hippocampal AMPA Receptor Function and Fear Memory

    Science.gov (United States)

    Xiong, Hui; Casse, Frédéric; Zhou, Yang; Zhou, Ming; Xiong, Zhi-Qi; Joëls, Marian; Martin, Stéphane; Krugers, Harm J.

    2015-01-01

    Glucocorticoid hormones, via activation of their receptors, promote memory consolidation, but the exact underlying mechanisms remain elusive. We examined how corticosterone regulates AMPA receptors (AMPARs), which are crucial for synaptic plasticity and memory formation. Combining a live imaging fluorescent recovery after photobleaching approach…

  3. The role of GH receptor tyrosine phosphorylation in Stat5 activation

    DEFF Research Database (Denmark)

    Hansen, J A; Hansen, L H; Wang, X

    1997-01-01

    . Mutated GH receptors lacking all but one of these three tyrosines are able to mediate a transcriptional response when transiently transfected into CHO cells together with a Spi 2.1 promoter/luciferase construct. Similarly, these GH receptors were found to be able to mediate activation of Stat5 DNA...

  4. Promoter reuse in prokaryotes

    NARCIS (Netherlands)

    Nijveen, H.; Matus-Garcia, M.; Passel, van M.W.J.

    2012-01-01

    Anecdotal evidence shows promoters being reused separate from their downstream gene, thus providing a mechanism for the efficient and rapid rewiring of a gene’s transcriptional regulation. We have identified over 4000 groups of highly similar promoters using a conservative sequence similarity search

  5. Plant Growth Promoting Rhizobacteria

    Indian Academy of Sciences (India)

    IAS Admin

    Plant Growth Promoting Rhizobacteria (PGPR) are a group of bacteria that enhances plant growth and yield via various plant growth promoting substances as well as biofertilizers. Given the negative environmental impact of artificial fertiliz- ers and their increasing costs, the use of beneficial soil micro- organisms such as ...

  6. Muscarinic receptor oligomerization.

    Science.gov (United States)

    Marsango, Sara; Ward, Richard J; Alvarez-Curto, Elisa; Milligan, Graeme

    2017-11-14

    G protein-coupled receptors (GPCRs) have been classically described as monomeric entities that function by binding in a 1:1 stoichiometric ratio to both ligand and downstream signalling proteins. However, in recent years, a growing number of studies has supported the hypothesis that these receptors can interact to form dimers and higher order oligomers although the molecular basis for these interactions, the overall quaternary arrangements and the functional importance of GPCR oligomerization remain topics of intense speculation. Muscarinic acetylcholine receptors belong to class A of the GPCR family. Each muscarinic receptor subtype has its own particular distribution throughout the central and peripheral nervous systems. In the central nervous system, muscarinic receptors regulate several sensory, cognitive, and motor functions while, in the peripheral nervous system, they are involved in the regulation of heart rate, stimulation of glandular secretion and smooth muscle contraction. Muscarinic acetylcholine receptors have long been used as a model for the study of GPCR structure and function and to address aspects of GPCR dimerization using a broad range of approaches. In this review, the prevailing knowledge regarding the quaternary arrangement for the various muscarinic acetylcholine receptors has been summarized by discussing work ranging from initial results obtained using more traditional biochemical approaches to those generated with more modern biophysical techniques. Copyright © 2017 The Authors. Published by Elsevier Ltd.. All rights reserved.

  7. Molecular identification and characterization of the dog motilin receptor.

    Science.gov (United States)

    Ohshiro, Hiroyuki; Nonaka, Miki; Ichikawa, Katsuomi

    2008-02-07

    Motilin, a 22-amino acid peptide hormone secreted by endocrine cells of the intestinal mucosa, plays an important role in the regulation of gastrointestinal motility. The actions of motilin agonists have been extensively investigated in dogs due to physiological similarities between the dog and human alimentary tracts. The amino acid sequence of the dog motilin receptor, however, was previously unknown. We have cloned a cDNA from dog stomach corresponding to the motilin receptor. The deduced protein shared 71% and 72% sequence identity with the human and rabbit motilin receptors, respectively. Expression of the dog motilin receptor in CHO cells promoted the typical cellular responses to the agonists, motilin and erythromycin. The rank order of potency determined for these agonists was similar to that found for the human motilin receptor, with motilin being more potent than erythromycin. Immunohistochemistry of the dog stomach revealed that the motilin receptor was localized in neuronal cell bodies and fibers. This is the first study detailing the cloning, expression, and functional characterization of the dog motilin receptor. Determination of the full sequence and functional properties of the dog motilin receptor will provide useful information enabling us to interpret previous and future studies of motilin agonists in dogs.

  8. Health-promoting schools

    DEFF Research Database (Denmark)

    Kwan, Stella Y L; Petersen, Poul Erik; Pine, Cynthia M

    2005-01-01

    them to develop lifelong sustainable attitudes and skills. Poor oral health can have a detrimental effect on children's quality of life, their performance at school and their success in later life. This paper examines the global need for promoting oral health through schools. The WHO Global School......Schools provide an important setting for promoting health, as they reach over 1 billion children worldwide and, through them, the school staff, families and the community as a whole. Health promotion messages can be reinforced throughout the most influential stages of children's lives, enabling...... Health Initiative and the potential for setting up oral health programmes in schools using the health-promoting school framework are discussed. The challenges faced in promoting oral health in schools in both developed and developing countries are highlighted. The importance of using a validated...

  9. Glucocorticoid Regulation of the Vitamin D Receptor

    Science.gov (United States)

    Hidalgo, Alejandro A.; Trump, Donald L.; Johnson, Candace S.

    2010-01-01

    Many studies indicate calcitriol has potent anti-tumor activity in different types of cancers. However, high levels of vitamin D can produce hypercalcemia in some patients. Glucocorticoids are used to ameliorate hypercalcemia and to enhance calcitriol anti-tumor activity. Calcitriol in combination with the glucocorticoid dexamethasone (Dex) increased vitamin D receptor (VDR) protein levels and ligand binding in squamous cell carcinoma VII (SCC). In this study we found that both calcitriol and Dex induce VDR- and glucocorticoid receptor (GR)-mediated transcription respectively, indicating both hormone receptors are active in SCC. Pre-treatment with Dex increases VDR-mediated transcription at the human CYP24A1 promoter. Whereas, pre-treatment with other steroid hormones, including dihydrotestosterone and R1881, has no effect on VDR-mediated transcription. Real-time PCR indicates treatment with Dex increases Vdr transcripts in a time-dependent manner, suggesting Dex may directly regulate expression of Vdr. Numerous putative glucocorticoid response elements (GREs) were found in the Vdr gene. Chromatin immunoprecipitation (ChIP) assay demonstrated GR binding at several putative GREs located within the mouse Vdr gene. However, none of the putative GREs studied increase GR-mediated transcription in luciferase reporter assays. In an attempt to identify the response element responsible for Vdr transcript regulation, future studies will continue to analyze newly identified GREs more distal from the Vdr gene promoter. PMID:20398752

  10. Glutamate receptor agonists

    DEFF Research Database (Denmark)

    Vogensen, Stine Byskov; Greenwood, Jeremy R; Bunch, Lennart

    2011-01-01

    stereogenic centers due to strict requirements in the agonist binding pocket of the activated state of the receptor. By contrast, there are many examples of achiral competitive antagonists. The present review addresses how stereochemistry affects the activity of glutamate receptor ligands. The review focuses...... mainly on agonists and discusses stereochemical and conformational considerations as well as biostructural knowledge of the agonist binding pockets, which is useful in the design of glutamate receptor agonists. Examples are chosen to demonstrate how stereochemistry not only determines how the agonist...

  11. P2X receptors

    OpenAIRE

    North, R. Alan

    2016-01-01

    Extracellular adenosine 5′-triphosphate (ATP) activates cell surface P2X and P2Y receptors. P2X receptors are membrane ion channels preferably permeable to sodium, potassium and calcium that open within milliseconds of the binding of ATP. In molecular architecture, they form a unique structural family. The receptor is a trimer, the binding of ATP between subunits causes them to flex together within the ectodomain and separate in the membrane-spanning region so as to open a central channel. P2...

  12. Serotonin Receptors in Hippocampus