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Sample records for antagonists induce favorable

  1. Non-NMDA receptor antagonist-induced drinking in rat

    Science.gov (United States)

    Xu, Z.; Johnson, A. K.

    1998-01-01

    Glutamate has been implicated in the central control of mechanisms that maintain body fluid homeostasis. The present studies demonstrate that intracerebroventricular (i.c.v.) injections of the non-N-methyl-d-aspartate (NMDA) receptor antagonists 6, 7-dinitroquinoxaline-2,3-dione (DNQX) and 6-cyano-7-nitroquinoxaline-2,3 dione (CNQX) induce drinking in rats. The dipsogenic effect of i.c.v. DNQX was antagonized by the non-NMDA receptor agonist alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA). The water intake induced by DNQX was also blocked by pretreatment with a NMDA receptor antagonist, MK-801, but not by angiotensin type 1 (AT1) or acetylcholine muscarinic receptor antagonists (losartan and atropine). The results indicate that non-NMDA receptors may exert a tonic inhibitory effect within brain circuits that control dipsogenic activity and that functional integrity of NMDA receptors may be required for the non-NMDA receptor antagonists to induce water intake. Copyright 1998 Published by Elsevier Science B.V.

  2. [Necrotic leg ulcer revealing vasculitis induced by vitamin K antagonists].

    Science.gov (United States)

    Chabli, H; Hocar, O; Akhdari, N; Amal, S; Hakkou, M; Hamdaoui, A

    2015-12-01

    Vitamin K antagonists are widely used in thromboembolic diseases. Hemorrhagic complications related to drug overdose represent their main side effect. We report a rare side effect, a severe and unexpected type of skin vasculitis - necrotic leg ulcer - induced by vitamin K antagonist. A 63-year-old female with a history of diabetes developed hyperalgesic necrotic ulcerations on the lower limbs one month after starting an acenocoumarol-based treatment for ischemic heart disease. Histological examination revealed lymphocytic vasculitis with fibrinoid necrosis. Etiological explorations searching for vasculitis were negative. In the absence of a precise etiology, drug-induced ulcer was suspected. Low molecular weight heparin was prescribed to replace acenocoumarol. The lesions slowly resolved with topical treatment. The chronological criteria and the negativity of etiological explorations allowed the diagnosis of vitamin K antagonist-induced necrotic skin ulcer. Clinicians should be aware of this rare complication induced by oral anticoagulants because of its practical therapeutic implications. This is the first case of necrotic leg ulcer induced by acenocoumarol corresponding histologically to necrotising lymphocytic vasculitis. Copyright © 2015 Elsevier Masson SAS. All rights reserved.

  3. FGFR antagonist induces protective autophagy in FGFR1-amplified breast cancer cell

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    Chen, Yi [The School of Biomedical Sciences, Chengdu Medical College, Chengdu 610083 (China); Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu (China); Xie, Xiaoyan; Li, Xinyi; Wang, Peiqi [State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University (China); Jing, Qian; Yue, Jiaqi; Liu, Yang [The School of Biomedical Sciences, Chengdu Medical College, Chengdu 610083 (China); Cheng, Zhong [Department of Gastrointestinal Surgery, West China Hospital, Sichuan University, Chengdu (China); Li, Jingyi, E-mail: li--jingyi@hotmail.com [The School of Biomedical Sciences, Chengdu Medical College, Chengdu 610083 (China); Song, Haixing [The School of Biomedical Sciences, Chengdu Medical College, Chengdu 610083 (China); Li, Guoyu, E-mail: liguoyulisa@163.com [School of Pharmacy, Shihezi University, Shihezi 832003 (China); Liu, Rui, E-mail: liurui_scu@hotmail.com [State Key Laboratory of Oral Diseases, West China College of Stomatology, Sichuan University (China); Wang, Jinhui [School of Pharmacy, Shihezi University, Shihezi 832003 (China)

    2016-05-20

    Breast cancer, representing approximately 30% of all gynecological cancer cases diagnosed yearly, is a leading cause of cancer-related mortality for women. Amplification of FGFR1 is frequently observed in breast cancers and is associated with poor prognosis. Though FGFRs have long been considered as anti-cancer drug targets, and a cluster of FGFR antagonists are currently under clinical trials, the precise cellular responses under the treatment of FGFR antagonists remains unclear. Here, we show that PD166866, an FGFR1-selective inhibitor, inhibits proliferation and triggers anoikis in FGFR1-amplified breast cancer cell lines. Notably, we demonstrate that PD166866 induces autophagy in FGFR1-amplified breast cancer cell lines, while blockage of autophagy by Atg5 knockdown further enhances the anti-proliferative activities of PD166866. Moreover, mechanistic study reveals that PD166866 induces autophagy through repressing Akt/mTOR signaling pathway. Together, the present study provides new insights into the molecular mechanisms underlying the anti-tumor activities of FGFR antagonists, and may further assist the FGFRs-based drug discovery. -- Highlights: •FGFR1 antagonist inhibits cell viability in FGFR1-amplified breast cancer cells. •FGFR1 antagonist induces autophagy in FGFR1-amplified breast cancer cells. •FGFR1 antagonist-induced autophagy is protective. •FGFR1 antagonist induces autophagy by inhibiting Akt/mTOR pathway.

  4. FGFR antagonist induces protective autophagy in FGFR1-amplified breast cancer cell

    International Nuclear Information System (INIS)

    Chen, Yi; Xie, Xiaoyan; Li, Xinyi; Wang, Peiqi; Jing, Qian; Yue, Jiaqi; Liu, Yang; Cheng, Zhong; Li, Jingyi; Song, Haixing; Li, Guoyu; Liu, Rui; Wang, Jinhui

    2016-01-01

    Breast cancer, representing approximately 30% of all gynecological cancer cases diagnosed yearly, is a leading cause of cancer-related mortality for women. Amplification of FGFR1 is frequently observed in breast cancers and is associated with poor prognosis. Though FGFRs have long been considered as anti-cancer drug targets, and a cluster of FGFR antagonists are currently under clinical trials, the precise cellular responses under the treatment of FGFR antagonists remains unclear. Here, we show that PD166866, an FGFR1-selective inhibitor, inhibits proliferation and triggers anoikis in FGFR1-amplified breast cancer cell lines. Notably, we demonstrate that PD166866 induces autophagy in FGFR1-amplified breast cancer cell lines, while blockage of autophagy by Atg5 knockdown further enhances the anti-proliferative activities of PD166866. Moreover, mechanistic study reveals that PD166866 induces autophagy through repressing Akt/mTOR signaling pathway. Together, the present study provides new insights into the molecular mechanisms underlying the anti-tumor activities of FGFR antagonists, and may further assist the FGFRs-based drug discovery. -- Highlights: •FGFR1 antagonist inhibits cell viability in FGFR1-amplified breast cancer cells. •FGFR1 antagonist induces autophagy in FGFR1-amplified breast cancer cells. •FGFR1 antagonist-induced autophagy is protective. •FGFR1 antagonist induces autophagy by inhibiting Akt/mTOR pathway.

  5. Serotonin 2C receptor antagonists induce fast-onset antidepressant effects.

    Science.gov (United States)

    Opal, M D; Klenotich, S C; Morais, M; Bessa, J; Winkle, J; Doukas, D; Kay, L J; Sousa, N; Dulawa, S M

    2014-10-01

    Current antidepressants must be administered for several weeks to produce therapeutic effects. We show that selective serotonin 2C (5-HT2C) antagonists exert antidepressant actions with a faster-onset (5 days) than that of current antidepressants (14 days) in mice. Subchronic (5 days) treatment with 5-HT2C antagonists induced antidepressant behavioral effects in the chronic forced swim test (cFST), chronic mild stress (CMS) paradigm and olfactory bulbectomy paradigm. This treatment regimen also induced classical markers of antidepressant action: activation of cAMP response element-binding protein (CREB) and induction of brain-derived neurotrophic factor (BDNF) in the medial prefrontal cortex (mPFC). None of these effects were induced by subchronic treatment with citalopram, a prototypical selective serotonin reuptake inhibitor (SSRI). Local infusion of 5-HT2C antagonists into the ventral tegmental area was sufficient to induce BDNF in the mPFC, and dopamine D1 receptor antagonist treatment blocked the antidepressant behavioral effects of 5-HT2C antagonists. 5-HT2C antagonists also activated mammalian target of rapamycin (mTOR) and eukaryotic elongation factor 2 (eEF2) in the mPFC, effects recently linked to rapid antidepressant action. Furthermore, 5-HT2C antagonists reversed CMS-induced atrophy of mPFC pyramidal neurons. Subchronic SSRI treatment, which does not induce antidepressant behavioral effects, also activated mTOR and eEF2 and reversed CMS-induced neuronal atrophy, indicating that these effects are not sufficient for antidepressant onset. Our findings reveal that 5-HT2C antagonists are putative fast-onset antidepressants, which act through enhancement of mesocortical dopaminergic signaling.

  6. Effect of beta-adrenergic receptor antagonists on nicotine-induced tail-tremor in rats.

    Science.gov (United States)

    Suemaru, K; Gomita, Y; Furuno, K; Araki, Y

    1993-09-01

    The effects of various beta-adrenergic receptor antagonists on nicotine-induced tail-tremor were investigated in rats. Atenolol (5 and 10 mg/kg, IP), arotinolol (5 and 10 mg/kg, IP), and carteolol (5 and 10 mg/kg, IP), hydrophilic beta-adrenergic receptor antagonists, did not affect the tail-tremor induced by nicotine given at a dose of 0.5 mg/kg SC. However, propranolol (5-20 mg/kg, IP) and pindolol (5-20 mg/kg, IP), nonselective and lipophilic beta-adrenergic receptor antagonists, did suppress the tail-tremor dose dependently. In contrast, metoprolol (5-20 mg/kg, IP), lipophilic and beta 1-selective adrenergic receptor antagonists, did not show such an effect. These results suggest that nicotine-induced tail-tremors may be mediated through central beta 2-adrenergic receptors as an appearance and developmental mechanism.

  7. Chronic Voluntary Ethanol Consumption Induces Favorable Ceramide Profiles in Selectively Bred Alcohol-Preferring (P Rats.

    Directory of Open Access Journals (Sweden)

    Jessica Godfrey

    Full Text Available Heavy alcohol consumption has detrimental neurologic effects, inducing widespread neuronal loss in both fetuses and adults. One proposed mechanism of ethanol-induced cell loss with sufficient exposure is an elevation in concentrations of bioactive lipids that mediate apoptosis, including the membrane sphingolipid metabolites ceramide and sphingosine. While these naturally-occurring lipids serve as important modulators of normal neuronal development, elevated levels resulting from various extracellular insults have been implicated in pathological apoptosis of neurons and oligodendrocytes in several neuroinflammatory and neurodegenerative disorders. Prior work has shown that acute administration of ethanol to developing mice increases levels of ceramide in multiple brain regions, hypothesized to be a mediator of fetal alcohol-induced neuronal loss. Elevated ceramide levels have also been implicated in ethanol-mediated neurodegeneration in adult animals and humans. Here, we determined the effect of chronic voluntary ethanol consumption on lipid profiles in brain and peripheral tissues from adult alcohol-preferring (P rats to further examine alterations in lipid composition as a potential contributor to ethanol-induced cellular damage. P rats were exposed for 13 weeks to a 20% ethanol intermittent-access drinking paradigm (45 ethanol sessions total or were given access only to water (control. Following the final session, tissues were collected for subsequent chromatographic analysis of lipid content and enzymatic gene expression. Contrary to expectations, ethanol-exposed rats displayed substantial reductions in concentrations of ceramides in forebrain and heart relative to non-exposed controls, and modest but significant decreases in liver cholesterol. qRT-PCR analysis showed a reduction in the expression of sphingolipid delta(4-desaturase (Degs2, an enzyme involved in de novo ceramide synthesis. These findings indicate that ethanol intake levels

  8. Chronic Voluntary Ethanol Consumption Induces Favorable Ceramide Profiles in Selectively Bred Alcohol-Preferring (P) Rats.

    Science.gov (United States)

    Godfrey, Jessica; Jeanguenin, Lisa; Castro, Norma; Olney, Jeffrey J; Dudley, Jason; Pipkin, Joseph; Walls, Stanley M; Wang, Wei; Herr, Deron R; Harris, Greg L; Brasser, Susan M

    2015-01-01

    Heavy alcohol consumption has detrimental neurologic effects, inducing widespread neuronal loss in both fetuses and adults. One proposed mechanism of ethanol-induced cell loss with sufficient exposure is an elevation in concentrations of bioactive lipids that mediate apoptosis, including the membrane sphingolipid metabolites ceramide and sphingosine. While these naturally-occurring lipids serve as important modulators of normal neuronal development, elevated levels resulting from various extracellular insults have been implicated in pathological apoptosis of neurons and oligodendrocytes in several neuroinflammatory and neurodegenerative disorders. Prior work has shown that acute administration of ethanol to developing mice increases levels of ceramide in multiple brain regions, hypothesized to be a mediator of fetal alcohol-induced neuronal loss. Elevated ceramide levels have also been implicated in ethanol-mediated neurodegeneration in adult animals and humans. Here, we determined the effect of chronic voluntary ethanol consumption on lipid profiles in brain and peripheral tissues from adult alcohol-preferring (P) rats to further examine alterations in lipid composition as a potential contributor to ethanol-induced cellular damage. P rats were exposed for 13 weeks to a 20% ethanol intermittent-access drinking paradigm (45 ethanol sessions total) or were given access only to water (control). Following the final session, tissues were collected for subsequent chromatographic analysis of lipid content and enzymatic gene expression. Contrary to expectations, ethanol-exposed rats displayed substantial reductions in concentrations of ceramides in forebrain and heart relative to non-exposed controls, and modest but significant decreases in liver cholesterol. qRT-PCR analysis showed a reduction in the expression of sphingolipid delta(4)-desaturase (Degs2), an enzyme involved in de novo ceramide synthesis. These findings indicate that ethanol intake levels achieved by

  9. Effects of sigma(1) receptor ligand MS-377 on D(2) antagonists-induced behaviors.

    Science.gov (United States)

    Karasawa, Jun-ichi; Takahashi, Shinji; Takagi, Kaori; Horikomi, Kazutoshi

    2002-10-01

    (R)-(+)-1-(4-Chlorophenyl)-3-[4-(2-methoxyethyl)piperazin-1-yl]methyl-2-pyrrolidinone L-tartrate (MS-377) is a novel antipsychotic agent with selective and high affinity for sigma(1) receptor. The present study was carried out to clarify the interaction of MS-377 with dopamine D(2) receptor antagonists (D(2) antagonists) in concurrent administration, and then the involvement of sigma receptors in the interaction. The effects of MS-377 on haloperidol- or sultopride-induced inhibition of apomorphine-induced climbing behavior and catalepsy were investigated in mice and rats, respectively. In addition, the effects of (+)-SKF-10,047 and SA4503, both of which are sigma receptor agonists, and WAY-100,635, which is a 5-HT(1A) receptor antagonist, on the interaction due to the concurrent use were also investigated. MS-377 potentiated the inhibitory effects of haloperidol or sultopride on apomorphine-induced climbing behavior in a dose-dependent manner. In contrast, MS-377 did not affect the catalepsy induction by these drugs. The potentiation of the inhibitory effects of haloperidol or sultopride on apomorphine-induced climbing behavior by MS-377 was not inhibited by WAY-100,635, but was inhibited by (+)-SKF-10,047 and SA4503. These findings showed that MS-377 potentiates the efficacy of D(2) antagonists, but it does not deteriorate the adverse effect. Moreover, sigma(1) receptors are involved in this potentiation of the efficacy of D(2) antagonists by MS-377.

  10. Uricase alkaline enzymosomes with enhanced stabilities and anti-hyperuricemia effects induced by favorable microenvironmental changes

    Science.gov (United States)

    Zhou, Yunli; Zhang, Mi; He, Dan; Hu, Xueyuan; Xiong, Huarong; Wu, Jianyong; Zhu, Biyue; Zhang, Jingqing

    2016-01-01

    Enzyme therapy is an effective strategy to treat diseases. Three strategies were pursued to provide the favorable microenvironments for uricase (UCU) to eventually improve its features: using the right type of buffer to constitute the liquid media where catalyze reactions take place; entrapping UCU inside the selectively permeable lipid vesicle membranes; and entrapping catalase together with UCU inside the membranes. The nanosized alkaline enzymosomes containing UCU/(UCU and catalase) (ESU/ESUC) in bicine buffer had better thermal, hypothermal, acid-base and proteolytic stabilities, in vitro and in vivo kinetic characteristics, and uric acid lowering effects. The favorable microenvironments were conducive to the establishment of the enzymosomes with superior properties. It was the first time that two therapeutic enzymes were simultaneously entrapped into one enzymosome having the right type of buffer to achieve added treatment efficacy. The development of ESU/ESUC in bicine buffer provides valuable tactics in hypouricemic therapy and enzymosomal application. PMID:26823332

  11. Novel neurokinin-1 antagonists as antiemetics for the treatment of chemotherapy-induced emesis.

    Science.gov (United States)

    Reddy, G Kesava; Gralla, Richard J; Hesketh, Paul J

    2006-04-01

    Despite significant advances in supportive care in oncology, many patients with cancer still experience chemotherapy- induced nausea and vomiting (CINV). Historically, there were only 3 neurotransmitter receptors (dopamine D2, cannabinoid- 1, and 5-hydroxytryptamine-3) that were the known targets for antiemetic therapy. Major advances in the management of chemotherapy-induced emesis were seen with the introduction of 5-hydroxytryptamine-3 receptor antagonists, which include palonosetron, ondansetron, tropisetron, dolasetron, and granisetron. However, recently, selective inhibitors of substance P have shown promising activity in the management of CINV in patients with cancer. Substance P mediates a number of biologic effects by binding to a specific neuroreceptor, neurokinin-1 (NK-1). Among the NK-1 receptor antagonists, aprepitant has been approved for the treatment of CINV. Currently, several other NK-1 receptor antagonists, including casopitant, vestipitant, netupitant, and SCH619734, are undergoing clinical evaluation for the prevention of CINV in patients with a variety of malignancies. The clinical potential of these novel NK-1 receptor antagonists and their respective ongoing clinical trials for the management of chemotherapy-induced emesis are discussed briefly herein.

  12. Attenuation of antagonist-induced impairment of dopamine receptors by L-prolyl-L-leucyl-glycinamide

    International Nuclear Information System (INIS)

    Saleh, M.I.M.

    1988-01-01

    The present study was undertaken in order to determine whether chronic,long-term postnatal challenge of rat pups per se, with specific dopamine D1 and D2 receptor antagonists, would modify the ontogeny of the respective receptor types. Since the neuropeptide L-prolyl-L-leucyl-glycinamide (PLG) attenuates the effect of haloperidol on dopamine D2 receptors in adult rats it was of interest to determine whether PLG would modulate antagonists-induced alterations in the ontogeny of striatal dopamine D1 and D2 receptors. Half of the rats were treated daily for 32 days from birth with SCH-23390, a selective dopamine D1 antagonist; or spiroperidol, a selective dopamine D2 antagonists; or both SCH-23390 and spiroperidol; or saline. The other half of the litters were treated with PLG, in combination with the other treatments. Animals were decapitated at 5, 8, and 12 weeks from birth for neurochemical analysis of the striatum. Chronic SCH-23390 treatment produced a 70-80% decrease in the binding of [ 3 H] SCH-23390 to striatal homogenates. The alteration at 5 weeks was associated with a 78% decrease in the Bmax for [ 3 H] SCH-23390 binding, and no change in the K D . Similarly, at 5, 8, and 12 weeks, chronic spiroperidol treatment reduced the binding of [ 3 H] spiroperidol to striatal homogenates by 70-80%

  13. Nocardia brasiliensis induces an immunosuppressive microenvironment that favors chronic infection in BALB/c mice.

    Science.gov (United States)

    Rosas-Taraco, Adrian G; Perez-Liñan, Amira R; Bocanegra-Ibarias, Paola; Perez-Rivera, Luz I; Salinas-Carmona, Mario C

    2012-07-01

    Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P 1 log) was also observed (P brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection.

  14. Nocardia brasiliensis Induces an Immunosuppressive Microenvironment That Favors Chronic Infection in BALB/c Mice

    Science.gov (United States)

    Rosas-Taraco, Adrian G.; Perez-Liñan, Amira R.; Bocanegra-Ibarias, Paola; Perez-Rivera, Luz I.

    2012-01-01

    Nocardia brasiliensis is an intracellular microorganism and the most common etiologic agent of actinomycetoma in the Americas. Several intracellular pathogens induce an immunosuppressive microenvironment through increases in CD4+ Foxp3+ regulatory T cells (Treg), thus downregulating other T-cell subpopulations and assuring survival in the host. In this study, we determined whether N. brasiliensis modulates T-lymphocyte responses and their related cytokine profiles in a murine experimental model. We also examined the relationship between N. brasiliensis immunomodulation and pathogenesis and bacterial survival. In early infection, Th17/Tc17 cells were increased at day 3 (P 1 log) was also observed (P brasiliensis modulates the immune system to induce an immunosuppressive microenvironment that benefits its survival during the chronic stage of infection. PMID:22547544

  15. Human immunodeficiency virus-induced pathology favored by cellular transmission and activation

    International Nuclear Information System (INIS)

    Lewis, D.E.; Yoffe, B.; Bosworth, C.G.; Hollinger, F.B.; Rich, R.R.

    1988-01-01

    Epidemiological data suggest that transmission of human immunodeficiency virus (HIV) occurs primarily by transference of virally infected cells. However, the efficiency of lytic productive infection induced by HIV after transmission of cell-associated virus vs. free virus is difficult to assess. The present studies compare the extent of depletion of CD4+ (helper/inducer) T cells after mixing uninfected cells with either free HIV or irradiated HIV-infected allogeneic or autologous cells in vitro. Rapid CD4+ cellular depletion occurred only in cultures containing allogeneic infected cells or after addition of a nonspecific T cell activation signal to cultures with autologous infected cells. These in vitro observations strongly support the epidemiological implication that interactions between infected and uninfected cells are the most efficient means of transmission and HIV-induced cytopathology in vivo. They also provide direct support for the concept that immunological stimulation by foreign cells infected with HIV dramatically increases the likelihood of transmission. These in vitro observations suggest a model for the acquisition of HIV in vivo and the role of cellular activation in dissemination of the virus to uninfected cells in an infected individual

  16. MYC-driven epigenetic reprogramming favors the onset of tumorigenesis by inducing a stem cell-like state.

    Science.gov (United States)

    Poli, Vittoria; Fagnocchi, Luca; Fasciani, Alessandra; Cherubini, Alessandro; Mazzoleni, Stefania; Ferrillo, Sara; Miluzio, Annarita; Gaudioso, Gabriella; Vaira, Valentina; Turdo, Alice; Giaggianesi, Miriam; Chinnici, Aurora; Lipari, Elisa; Bicciato, Silvio; Bosari, Silvano; Todaro, Matilde; Zippo, Alessio

    2018-03-09

    Breast cancer consists of highly heterogeneous tumors, whose cell of origin and driver oncogenes are difficult to be uniquely defined. Here we report that MYC acts as tumor reprogramming factor in mammary epithelial cells by inducing an alternative epigenetic program, which triggers loss of cell identity and activation of oncogenic pathways. Overexpression of MYC induces transcriptional repression of lineage-specifying transcription factors, causing decommissioning of luminal-specific enhancers. MYC-driven dedifferentiation supports the onset of a stem cell-like state by inducing the activation of de novo enhancers, which drive the transcriptional activation of oncogenic pathways. Furthermore, we demonstrate that the MYC-driven epigenetic reprogramming favors the formation and maintenance of tumor-initiating cells endowed with metastatic capacity. This study supports the notion that MYC-driven tumor initiation relies on cell reprogramming, which is mediated by the activation of MYC-dependent oncogenic enhancers, thus establishing a therapeutic rational for treating basal-like breast cancers.

  17. Brief treatment with the glucocorticoid receptor antagonist mifeprestone normalizes the corticosterone-induced reduction of adult hippocampal neurogenesis.

    NARCIS (Netherlands)

    Mayer, J.; Klumpers, L.; Maslam, S.; de Kloet, E.R.; Joëls, M.; Lucassen, P.J.

    2006-01-01

    The glucocorticoid receptor antagonist mifepristone has been shown to rapidly and effectively ameliorate symptoms of psychotic major depression. To better understand its mechanism, we investigated mifepristone's cellular effects, and found that it rapidly reversed a chronic corticosterone-induced

  18. Population structure induces a symmetry breaking favoring the emergence of cooperation.

    Directory of Open Access Journals (Sweden)

    Jorge M Pacheco

    2009-12-01

    Full Text Available The evolution of cooperation described in terms of simple two-person interactions has received considerable attention in recent years, where several key results were obtained. Among those, it is now well established that the web of social interaction networks promotes the emergence of cooperation when modeled in terms of symmetric two-person games. Up until now, however, the impacts of the heterogeneity of social interactions into the emergence of cooperation have not been fully explored, as other aspects remain to be investigated. Here we carry out a study employing the simplest example of a prisoner's dilemma game in which the benefits collected by the participants may be proportional to the costs expended. We show that the heterogeneous nature of the social network naturally induces a symmetry breaking of the game, as contributions made by cooperators may become contingent on the social context in which the individual is embedded. A new, numerical, mean-field analysis reveals that prisoner's dilemmas on networks no longer constitute a defector dominance dilemma--instead, individuals engage effectively in a general coordination game. We find that the symmetry breaking induced by population structure profoundly affects the evolutionary dynamics of cooperation, dramatically enhancing the feasibility of cooperators: cooperation blooms when each cooperator contributes the same cost, equally shared among the plethora of games in which she participates. This work provides clear evidence that, while individual rational reasoning may hinder cooperative actions, the intricate nature of social interactions may effectively transform a local dilemma of cooperation into a global coordination problem.

  19. Prostaglandin E2/leukotriene B4 balance induced by Lutzomyia longipalpis saliva favors Leishmania infantum infection.

    Science.gov (United States)

    Araújo-Santos, Théo; Prates, Deboraci Brito; França-Costa, Jaqueline; Luz, Nívea F; Andrade, Bruno B; Miranda, José Carlos; Brodskyn, Claudia I; Barral, Aldina; Bozza, Patrícia T; Borges, Valéria Matos

    2014-12-20

    Eicosanoids and sand fly saliva have a critical role in the Leishmania infection. Here, we evaluated the effect of Lutzomyia longipalpis salivary gland sonicate (SGS) on neutrophil and monocyte recruitment and activation of eicosanoid production in a murine model of inflammation. C57BL/6 mice were inoculated intraperitonealy with Lutzomyia longipalpis SGS or Leishmania infantum or both, followed by analyses of cell recruitment, parasite load and eicosanoid production. Intraperitoneal injection of Lutzomyia longipalpis SGS together with Leishmania infantum induced an early increased parasite viability in monocytes and neutrophils. L. longipalpis SGS increased prostaglandin E2 (PGE2), but reduced leukotriene B4 (LTB4) production ex vivo in peritoneal leukocytes. In addition, the pharmacological inhibition of cyclooxygenase 2 (COX-2) with NS-398 decreased parasite viability inside macrophages during Leishmania infection in the presence of L. longipalpis SGS arguing that PGE2 production is associated with diminished parasite killing. These findings indicate that L. longipalpis SGS is a critical factor driving immune evasion of Leishmania through modulation of PGE2/LTB4 axis, which may represent an important mechanism on establishment of the infection.

  20. Transcriptional Changes in Canine Distemper Virus-Induced Demyelinating Leukoencephalitis Favor a Biphasic Mode of Demyelination

    Science.gov (United States)

    Ulrich, Reiner; Puff, Christina; Wewetzer, Konstantin; Kalkuhl, Arno; Deschl, Ulrich; Baumgärtner, Wolfgang

    2014-01-01

    Canine distemper virus (CDV)-induced demyelinating leukoencephalitis in dogs (Canis familiaris) is suggested to represent a naturally occurring translational model for subacute sclerosing panencephalitis and multiple sclerosis in humans. The aim of this study was a hypothesis-free microarray analysis of the transcriptional changes within cerebellar specimens of five cases of acute, six cases of subacute demyelinating, and three cases of chronic demyelinating and inflammatory CDV leukoencephalitis as compared to twelve non-infected control dogs. Frozen cerebellar specimens were used for analysis of histopathological changes including demyelination, transcriptional changes employing microarrays, and presence of CDV nucleoprotein RNA and protein using microarrays, RT-qPCR and immunohistochemistry. Microarray analysis revealed 780 differentially expressed probe sets. The dominating change was an up-regulation of genes related to the innate and the humoral immune response, and less distinct the cytotoxic T-cell-mediated immune response in all subtypes of CDV leukoencephalitis as compared to controls. Multiple myelin genes including myelin basic protein and proteolipid protein displayed a selective down-regulation in subacute CDV leukoencephalitis, suggestive of an oligodendrocyte dystrophy. In contrast, a marked up-regulation of multiple immunoglobulin-like expressed sequence tags and the delta polypeptide of the CD3 antigen was observed in chronic CDV leukoencephalitis, in agreement with the hypothesis of an immune-mediated demyelination in the late inflammatory phase of the disease. Analysis of pathways intimately linked to demyelination as determined by morphometry employing correlation-based Gene Set Enrichment Analysis highlighted the pathomechanistic importance of up-regulated genes comprised by the gene ontology terms “viral replication” and “humoral immune response” as well as down-regulated genes functionally related to “metabolite and energy

  1. Transcriptional changes in canine distemper virus-induced demyelinating leukoencephalitis favor a biphasic mode of demyelination.

    Directory of Open Access Journals (Sweden)

    Reiner Ulrich

    Full Text Available Canine distemper virus (CDV-induced demyelinating leukoencephalitis in dogs (Canis familiaris is suggested to represent a naturally occurring translational model for subacute sclerosing panencephalitis and multiple sclerosis in humans. The aim of this study was a hypothesis-free microarray analysis of the transcriptional changes within cerebellar specimens of five cases of acute, six cases of subacute demyelinating, and three cases of chronic demyelinating and inflammatory CDV leukoencephalitis as compared to twelve non-infected control dogs. Frozen cerebellar specimens were used for analysis of histopathological changes including demyelination, transcriptional changes employing microarrays, and presence of CDV nucleoprotein RNA and protein using microarrays, RT-qPCR and immunohistochemistry. Microarray analysis revealed 780 differentially expressed probe sets. The dominating change was an up-regulation of genes related to the innate and the humoral immune response, and less distinct the cytotoxic T-cell-mediated immune response in all subtypes of CDV leukoencephalitis as compared to controls. Multiple myelin genes including myelin basic protein and proteolipid protein displayed a selective down-regulation in subacute CDV leukoencephalitis, suggestive of an oligodendrocyte dystrophy. In contrast, a marked up-regulation of multiple immunoglobulin-like expressed sequence tags and the delta polypeptide of the CD3 antigen was observed in chronic CDV leukoencephalitis, in agreement with the hypothesis of an immune-mediated demyelination in the late inflammatory phase of the disease. Analysis of pathways intimately linked to demyelination as determined by morphometry employing correlation-based Gene Set Enrichment Analysis highlighted the pathomechanistic importance of up-regulated genes comprised by the gene ontology terms "viral replication" and "humoral immune response" as well as down-regulated genes functionally related to "metabolite and energy

  2. Pushing the threshold: how NMDAR antagonists induce homeostasis through protein synthesis to remedy depression

    Science.gov (United States)

    Raab-Graham, Kimberly F.; Workman, Emily R.; Namjoshi, Sanjeev; Niere, Farr

    2016-01-01

    Healthy neurons have an optimal operating range, coded globally by the frequency of action potentials or locally by calcium. The maintenance of this range is governed by homeostatic plasticity. Here, we discuss how new approaches to treat depression alter synaptic activity. These approaches induce the neuron to recruit homeostatic mechanisms to relieve depression. Homeostasis generally implies that the direction of activity necessary to restore the neuron’s critical operating range is opposite in direction to its current activity pattern. Unconventional antidepressant therapies deep brain stimulation and NMDAR antagonists alter the neuron’s “depressed” state by pushing the neuron’s current activity in the same direction but to the extreme edge. These therapies rally the intrinsic drive of neurons in the opposite direction, thereby allowing the cell to return to baseline activity, form new synapses, and restore proper communication. In this review, we discuss seminal studies on protein synthesis dependent homeostatic plasticity and their contribution to our understanding of molecular mechanisms underlying the effectiveness of NMDAR antagonists as rapid antidepressants. Rapid antidepressant efficacy is likely to require a cascade of mRNA translational regulation. Emerging evidence suggests that changes in synaptic strength or intrinsic excitability converge on the same protein synthesis pathways, relieving depressive symptoms. Thus, we address the question: Are there multiple homeostatic mechanisms that induce the neuron and neuronal circuits to self-correct to regulate mood in vivo? Targeting alternative ways to induce homeostatic protein synthesis may provide, faster, safer, and longer lasting antidepressants. PMID:27125595

  3. From the Cover: Glutamate antagonists limit tumor growth

    Science.gov (United States)

    Rzeski, Wojciech; Turski, Lechoslaw; Ikonomidou, Chrysanthy

    2001-05-01

    Neuronal progenitors and tumor cells possess propensity to proliferate and to migrate. Glutamate regulates proliferation and migration of neurons during development, but it is not known whether it influences proliferation and migration of tumor cells. We demonstrate that glutamate antagonists inhibit proliferation of human tumor cells. Colon adenocarcinoma, astrocytoma, and breast and lung carcinoma cells were most sensitive to the antiproliferative effect of the N-methyl-D-aspartate antagonist dizocilpine, whereas breast and lung carcinoma, colon adenocarcinoma, and neuroblastoma cells responded most favorably to the -amino-3-hydroxy-5-methyl-4-isoxazole-propionate antagonist GYKI52466. The antiproliferative effect of glutamate antagonists was Ca2+ dependent and resulted from decreased cell division and increased cell death. Morphological alterations induced by glutamate antagonists in tumor cells consisted of reduced membrane ruffling and pseudopodial protrusions. Furthermore, glutamate antagonists decreased motility and invasive growth of tumor cells. These findings suggest anticancer potential of glutamate antagonists.

  4. US -endorphin-(1-27) is a naturally occurring antagonist to etorphine-induced analgesia

    Energy Technology Data Exchange (ETDEWEB)

    Nicolas, P.; Li, C.H.

    1985-05-01

    The potent opioid peptide US -endorphin is found in the brain and pituitary with two related fragments, US -endorphin-(1-27) and US -endorphin-(1-26). The fragments, retain substantial opioid-receptor binding activity but are virtually inactive analgesically. US -Endorphin-(1-27) inhibits US -endorphin-induced and etorphine-induced analgesia when coinjected intracerebroventricularly into mice. Antagonism by competition at the same site(s) is suggested from parallel shifts of the dose-response curves of etorphine or US -endorphin in the presence of US -endorphin-(1-27). Its potency is 4-5 times greater than that of the opiate antagonist naloxone. US -Endorphin-(1-26) does not antagonize the antinociceptive action of etorphine or US -endorphin in doses up to 500 pmol per animal.

  5. Enhanced bradycardia induced by beta-adrenoceptor antagonists in rats pretreated with isoniazid.

    Science.gov (United States)

    Vidrio, H; Sánchez-Salvatori, M A; Medina, M

    1998-12-01

    High doses of isoniazid increase hypotension induced by vasodilators and change the accompanying reflex tachycardia to bradycardia, an interaction attributed to decreased synthesis of brain gamma-aminobutyric acid (GABA). In the present study, the possible enhancement by isoniazid of bradycardia induced by beta-adrenoceptor antagonists was determined in rats anaesthetised with chloralose-urethane. Isoniazid significantly increased bradycardia after propranolol, pindolol, labetalol and atenolol, as well as after clonidine, but not after hexamethonium or carbachol. Enhancement was not observed in rats pretreated with methylatropine or previously vagotomised. These results are compatible with interference by isoniazid with GABAergic inhibition of cardiac parasympathetic tone. Such interference could be exerted centrally, possibly at the nucleus ambiguus, or peripherally at the sinus node.

  6. Elevation of cytosolic calcium level triggers calcium antagonist-induced gingival overgrowth.

    Science.gov (United States)

    Hattori, Toshimi; Wang, Pao-Li

    2008-03-31

    Calcium (Ca2+) antagonists induce gingival overgrowth as a side effect but the pathogenic mechanism is still unknown. The Ca2+-channel activator Bay K 8644 elevates intracellular Ca2+ concentration ([Ca2+]i) and enhances the cell proliferation of gingival fibroblasts in a dose-dependent manner. Verapamil, an L-type Ca2+-channel blocker, also elevates [Ca2+]i in gingival fibroblasts, but it has no effect on other fibroblasts such as those of the lung, skin, and muscle. Moreover, verapamil enhances the proliferation of fibroblasts of the gingiva but has no effect on the proliferation of those of other tissues. These findings confirm that [Ca2+]i elevation induces the proliferation of gingival fibroblasts.

  7. The Dual Orexin Receptor Antagonist Almorexant Induces Sleep and Decreases Orexin-Induced Locomotion by Blocking Orexin 2 Receptors

    Science.gov (United States)

    Mang, Géraldine M.; Dürst, Thomas; Bürki, Hugo; Imobersteg, Stefan; Abramowski, Dorothee; Schuepbach, Edi; Hoyer, Daniel; Fendt, Markus; Gee, Christine E.

    2012-01-01

    Study Objectives: Orexin peptides activate orexin 1 and orexin 2 receptors (OX1R and OX2R), regulate locomotion and sleep-wake. The dual OX1R/OX2R antagonist almorexant reduces activity and promotes sleep in multiple species, including man. The relative contributions of the two receptors in locomotion and sleep/wake regulation were investigated in mice. Design: Mice lacking orexin receptors were used to determine the contribution of OX1R and OX2R to orexin A-induced locomotion and to almorexant-induced sleep. Setting: N/A. Patients or Participants: C57BL/6J mice and OX1R+/+, OX1R-/-, OX2R+/+, OX2R-/- and OX1R-/-/OX2R-/- mice. Interventions: Intracerebroventricular orexin A; oral dosing of almorexant. Measurements and Results: Almorexant attenuated orexin A-induced locomotion. As in other species, almorexant dose-dependently increased rapid eye movement sleep (REM) and nonREM sleep in mice. Almorexant and orexin A were ineffective in OX1R-/-/OX2R-/- mice. Both orexin A-induced locomotion and sleep induction by almorexant were absent in OX2R-/- mice. Interestingly, almorexant did not induce cataplexy in wild-type mice under conditions where cataplexy was seen in mice lacking orexins and in OX1R-/-/OX2R-/- mice. Almorexant dissociates very slowly from OX2R as measured functionally and in radioligand binding. Under non equilibrium conditions in vitro, almorexant was a dual antagonist whereas at equilibrium, almorexant became OX2R selective. Conclusions: In vivo, almorexant specifically inhibits the actions of orexin A. The two known orexin receptors mediate sleep induction by almorexant and orexin A-induced locomotion. However, OX2R activation mediates locomotion induction by orexin A and antagonism of OX2R is sufficient to promote sleep in mice. Citation: Mang GM; Dürst T; Bürki H; Imobersteg S; Abramowski D; Schuepbach E; Hoyer D; Fendt M; Gee CE. The dual orexin receptor antagonist almorexant induces sleep and decreases orexin-induced locomotion by blocking orexin

  8. Effect of the CRF1-receptor antagonist pexacerfont on stress-induced eating and food craving.

    Science.gov (United States)

    Epstein, David H; Kennedy, Ashley P; Furnari, Melody; Heilig, Markus; Shaham, Yavin; Phillips, Karran A; Preston, Kenzie L

    2016-12-01

    In rodents, antagonism of receptors for corticotropin-releasing factor (CRF) blocks stress-induced reinstatement of drug or palatable food seeking. To test anticraving properties of the CRF 1 antagonist pexacerfont in humans. We studied stress-induced eating in people scoring high on dietary restraint (food preoccupation and chronic unsuccessful dieting) with body-mass index (BMI) >22. In a double-blind, between-groups trial, 31 "restrained" eaters were stabilized on either pexacerfont (300 mg/day for 7 days, then 100 mg/day for 21 days) or placebo. On day 15, they underwent a math-test stressor; during three subsequent visits, they heard personalized craving-induction scripts. In each session, stress-induced food consumption and craving were assessed in a bogus taste test and on visual analog scales. We used digital video to monitor daily ingestion of study capsules and nightly rating of food problems/preoccupation on the Yale Food Addiction Scale (YFAS). The study was stopped early due to an administrative interpretation of US federal law, unrelated to safety or outcome. The bogus taste tests suggested some protective effect of pexacerfont against eating after a laboratory stressor (r effect  = 0.30, 95 % CL = -0.12, 0.63, Bayes factor 11.30). Similarly, nightly YFAS ratings were lower with pexacerfont than placebo (r effect  = 0.39, CI 0.03, 0.66), but this effect should be interpreted with caution because it was present from the first night of pill ingestion, despite pexacerfont's slow pharmacokinetics. The findings may support further investigation of the anticraving properties of CRF 1 antagonists, especially for food.

  9. Intra-ventral pallidal glutamate antagonists block expression of morphine-induced place preference.

    Science.gov (United States)

    Dallimore, Jeanine E; Mickiewicz, Amanda L; Napier, T Celeste

    2006-10-01

    The role of ionotropic glutamate receptors within the ventral pallidum (VP) in the expression of conditioned place preference (CPP) and motor adaptations to morphine was evaluated. VP-cannulated rats were subjected to 3 days of conditioning in which saline was paired to one distinct chamber in the morning and morphine (8 mg/kg ip or its vehicle) was paired to an alternate chamber in the afternoon. This induced (a) CPP expression in drug-free rats 1 day later, which was blocked by immediate pretreatments with intra-VP injections of a glutamate antagonist cocktail (DL-2-amino-5- phosphonopentanoic acid lithium salt [AP-5] + 6-cyano-7-nitroquinoxaline-2,3-dione disodium salt [CNQX]), and (b) changes in motor function expressed following an acute morphine challenge 18 days later, which were absent if preceded by a 10-day treatment with the glutamate antagonists injected unilaterally once daily in alternating hemispheres. Thus, VP ionotropic glutamate receptors are critical mediators of the expression of place preference and motor adaptations subsequent to repeated morphine exposure.

  10. Testosterone deficiency induced by progressive stages of diabetes mellitus impairs glucose metabolism and favors glycogenesis in mature rat Sertoli cells.

    Science.gov (United States)

    Rato, Luís; Alves, Marco G; Duarte, Ana I; Santos, Maria S; Moreira, Paula I; Cavaco, José E; Oliveira, Pedro F

    2015-09-01

    The incidence of type 2 diabetes mellitus and its prodromal stage, pre-diabetes, is rapidly increasing among young men, leading to disturbances in testosterone synthesis. However, the impact of testosterone deficiency induced by these progressive stages of diabetes on the metabolic behavior of Sertoli cells remains unknown. We evaluated the effects of testosterone deficiency associated with pre-diabetes and type 2 diabetes on Sertoli cells metabolism, by measuring (1) the expression and/or activities of glycolysis and glycogen metabolism-related proteins and (2) the metabolite secretion/consumption in Sertoli cells obtained from rat models of different development stages of the disease, to unveil the mechanisms by which testosterone deregulation may affect spermatogenesis. Glucose and pyruvate uptake were decreased in cells exposed to the testosterone concentration found in pre-diabetic rats (600nM), whereas the decreased testosterone concentrations found in type 2 diabetic rats (7nM) reversed this profile. Lactate production was not altered, although the expression and/or activity of lactate dehydrogenase and monocarboxylate transporter 4 were affected by progressive testosterone-deficiency. Sertoli cells exposed to type 2 diabetic conditions exhibited intracellular glycogen accumulation. These results illustrate that gradually reduced levels of testosterone, induced by progressive stages of diabetes mellitus, favor a metabolic reprogramming toward glycogen synthesis. Our data highlights a pivotal role for testosterone in the regulation of spermatogenesis metabolic support by Sertoli cells, particularly in individuals suffering from metabolic diseases. Such alterations may be in the basis of male subfertility/infertility associated with the progression of diabetes mellitus. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Induction of the Wnt antagonist Dickkopf-1 is involved in stress-induced hippocampal damage.

    Directory of Open Access Journals (Sweden)

    Francesco Matrisciano

    Full Text Available The identification of mechanisms that mediate stress-induced hippocampal damage may shed new light into the pathophysiology of depressive disorders and provide new targets for therapeutic intervention. We focused on the secreted glycoprotein Dickkopf-1 (Dkk-1, an inhibitor of the canonical Wnt pathway, involved in neurodegeneration. Mice exposed to mild restraint stress showed increased hippocampal levels of Dkk-1 and reduced expression of β-catenin, an intracellular protein positively regulated by the canonical Wnt signalling pathway. In adrenalectomized mice, Dkk-1 was induced by corticosterone injection, but not by exposure to stress. Corticosterone also induced Dkk-1 in mouse organotypic hippocampal cultures and primary cultures of hippocampal neurons and, at least in the latter model, the action of corticosterone was reversed by the type-2 glucocorticoid receptor antagonist mifepristone. To examine whether induction of Dkk-1 was causally related to stress-induced hippocampal damage, we used doubleridge mice, which are characterized by a defective induction of Dkk-1. As compared to control mice, doubleridge mice showed a paradoxical increase in basal hippocampal Dkk-1 levels, but no Dkk-1 induction in response to stress. In contrast, stress reduced Dkk-1 levels in doubleridge mice. In control mice, chronic stress induced a reduction in hippocampal volume associated with neuronal loss and dendritic atrophy in the CA1 region, and a reduced neurogenesis in the dentate gyrus. Doubleridge mice were resistant to the detrimental effect of chronic stress and, instead, responded to stress with increases in dendritic arborisation and neurogenesis. Thus, the outcome of chronic stress was tightly related to changes in Dkk-1 expression in the hippocampus. These data indicate that induction of Dkk-1 is causally related to stress-induced hippocampal damage and provide the first evidence that Dkk-1 expression is regulated by corticosteroids in the central

  12. Inhibition of common cold-induced aggravation of childhood asthma by leukotriene receptor antagonists.

    Science.gov (United States)

    Yoshihara, Shigemi; Fukuda, Hironobu; Abe, Toshio; Nishida, Mitsuhiro; Yamada, Yumi; Kanno, Noriko; Arisaka, Osamu

    2012-09-01

    Virus infection is an important risk factor for aggravation of childhood asthma. The objective of this study was to examine the effect of drugs on aggravation of asthma induced by a common cold. Asthma control was examined in a survey of 1,014 Japanese pediatric patients with bronchial asthma. The occurrence of common cold, asthma control, and drugs used for asthma control were investigated using a modified Childhood Asthma Control Test (C-ACT) for patients aged cold and aggravation of asthma were significantly higher in patients aged cold-induced aggravation was significantly less effective in patients aged cold, asthma control was significantly more effective for those treated with leukotriene receptor antagonists (LTRAs) compared to treatment without LTRAs. Asthma control did not differ between patients who did or did not take inhaled corticosteroids or long-acting β2 stimulants. These findings showed a high prevalence of common cold in younger patients with childhood asthma and indicated that common cold can induce aggravation of asthma. LTRAs are useful for long-term asthma control in very young patients who develop an asthma attack due to a common cold.

  13. NPS 2143, a selective calcium-sensing receptor antagonist inhibits lipopolysaccharide-induced pulmonary inflammation.

    Science.gov (United States)

    Lee, Jae-Won; Park, Hyun Ah; Kwon, Ok-Kyoung; Park, Ji-Won; Lee, Gilhye; Lee, Hee Jae; Lee, Seung Jin; Oh, Sei-Ryang; Ahn, Kyung-Seop

    2017-10-01

    NPS 2143, a novel and selective antagonist of calcium-sensing receptor (CaSR) has been reported to possess anti-inflammatory activity. In the present study, we examined the protective effect of NPS 2143 on lipopolysaccharide (LPS)-induced acute lung injury (ALI). NPS 2143 pretreatment significantly inhibited the influx of inflammatory cells and the expression of monocyte chemoattractant protein-1 (MCP-1) in the lung of mice with LPS-induced ALI. NPS 2143 decreased the levels of neutrophil elastase (NE) and protein concentration in the bronchoalveolar lavage fluid (BALF). NPS 2143 also reduced the production of inflammatory cytokines such as tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in the BALF and serum. In addition, NPS 2143 attenuated the expression of inducible nitric oxide synthase (iNOS) and cyclooxygenase-2 (COX-2), and increased the activation of AMP-activated protein kinase (AMPK) in the lung. NPS 2143 also downregulated the activation of nuclear factor-kappa B (NF-κB) in the lung. In LPS-stimulated H292 airway epithelial cells, NPS 2143 attenuated the releases of IL-6 and MCP-1. Furthermore, NPS 2143 upregulated the activation of AMPK and downregulated the activation of NF-κB. These results suggest that NPS 2143 could be potential agent for the treatment of inflammatory diseases including ALI. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Definition of critical periods for Hedgehog pathway antagonist-induced holoprosencephaly, cleft lip, and cleft palate.

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    Galen W Heyne

    Full Text Available The Hedgehog (Hh signaling pathway mediates multiple spatiotemporally-specific aspects of brain and face development. Genetic and chemical disruptions of the pathway are known to result in an array of structural malformations, including holoprosencephaly (HPE, clefts of the lip with or without cleft palate (CL/P, and clefts of the secondary palate only (CPO. Here, we examined patterns of dysmorphology caused by acute, stage-specific Hh signaling inhibition. Timed-pregnant wildtype C57BL/6J mice were administered a single dose of the potent pathway antagonist vismodegib at discrete time points between gestational day (GD 7.0 and 10.0, an interval approximately corresponding to the 15th to 24th days of human gestation. The resultant pattern of facial and brain dysmorphology was dependent upon stage of exposure. Insult between GD7.0 and GD8.25 resulted in HPE, with peak incidence following exposure at GD7.5. Unilateral clefts of the lip extending into the primary palate were also observed, with peak incidence following exposure at GD8.875. Insult between GD9.0 and GD10.0 resulted in CPO and forelimb abnormalities. We have previously demonstrated that Hh antagonist-induced cleft lip results from deficiency of the medial nasal process and show here that CPO is associated with reduced growth of the maxillary-derived palatal shelves. By defining the critical periods for the induction of HPE, CL/P, and CPO with fine temporal resolution, these results provide a mechanism by which Hh pathway disruption can result in "non-syndromic" orofacial clefting, or HPE with or without co-occurring clefts. This study also establishes a novel and tractable mouse model of human craniofacial malformations using a single dose of a commercially available and pathway-specific drug.

  15. The Histamine H3 Receptor Antagonist DL77 Ameliorates MK801-Induced Memory Deficits in Rats

    Directory of Open Access Journals (Sweden)

    Nermin Eissa

    2018-02-01

    Full Text Available The role of Histamine H3 receptors (H3Rs in memory, and the prospective of H3R antagonists in pharmacological control of neurodegenerative disorders, e.g., Alzheimer disease (AD is well-accepted. For that reason, the procognitive effects of the H3R antagonist DL77 on cognitive impairments induced with MK801 were tested in an inhibitory passive avoidance paradigm (PAP and novel object recognition (NOR task in adult male rats, using donepezil (DOZ as a standard drug. Acute systemic pretreatment with DL77 (2.5, 5, and 10 mg/kg, i.p. significantly ameliorated memory deficits induced with MK801 in PAP (all P < 0.05, n = 7. The ameliorative effect of most promising dose of DL77 (5 mg/kg, i.p. was reversed when rats were co-injected with the H3R agonist R-(α-methylhistamine (RAMH, 10 mg/kg, i.p. (p = 0.701 for MK801-amnesic group vs. MK801+DL77+RAMH group, n = 6. In the NOR paradigm, DL77 (5 mg/kg, i.p. counteracted long-term memory (LTM deficits induced with MK801 (P < 0.05, n = 6–8, and the DL77-provided effect was similar to that of DOZ (p = 0.788, n = 6–8, and was reversed when rats were co-injected with RAMH (10 mg/kg, i.p. (p = 0.877, n = 6, as compared to the (MK801-amnesic group. However, DL77 (5 mg/kg, i.p. did not alter short-term memory (STM impairment in NOR test (p = 0.772, n = 6–8, as compared to (MK801-amnesic group. Moreover, DL77 (5 mg/kg failed to modify anxiety and locomotor behaviors of animals innate to elevated-plus maze (EPM (p = 0.67 for percentage of time spent exploring the open arms, p = 0.52 for number of entries into the open arms, p = 0.76 for percentage of entries into the open arms, and p = 0.73 number of closed arm entries as compared to saline-treated groups, all n = 6, demonstrating that the procognitive effects observed in PAP or NOR tests were unconnected to alterations in emotions or in natural locomotion of tested animals. These results signify the potential involvement of H3Rs in modulating

  16. Interleukin-1 receptor antagonist protects against lipopolysaccharide induced diaphragm weakness in preterm lambs.

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    Kanakeswary Karisnan

    Full Text Available Chorioamnionitis (inflammation of the fetal membranes is strongly associated with preterm birth and in utero exposure to inflammation significantly impairs contractile function in the preterm lamb diaphragm. The fetal inflammatory response to intra-amniotic (IA lipopolysaccharide (LPS is orchestrated via interleukin 1 (IL-1. We aimed to determine if LPS induced contractile dysfunction in the preterm diaphragm is mediated via the IL-1 pathway. Pregnant ewes received IA injections of recombinant human IL-1 receptor antagonist (rhIL-1ra (Anakinra; 100 mg or saline (Sal 3 h prior to second IA injections of LPS (4 mg or Sal at 119d gestational age (GA. Preterm lambs were killed after delivery at 121d GA (term = 150 d. Muscle fibres dissected from the right hemi-diaphragm were mounted in an in vitro muscle test system for assessment of contractile function. The left hemi-diaphragm was snap frozen for molecular and biochemical analyses. Maximum specific force in lambs exposed to IA LPS (Sal/LPS group was 25% lower than in control lambs (Sal/Sal group; p=0.025. LPS-induced diaphragm weakness was associated with higher plasma IL-6 protein, diaphragm IL-1β mRNA and oxidised glutathione levels. Pre-treatment with rhIL-1ra (rhIL-1ra/LPS ameliorated the LPS-induced diaphragm weakness and blocked systemic and local inflammatory responses, but did not prevent the rise in oxidised glutathione. These findings indicate that LPS induced diaphragm dysfunction is mediated via IL-1 and occurs independently of oxidative stress. Therefore, the IL-1 pathway represents a potential therapeutic target in the management of impaired diaphragm function in preterm infants.

  17. Amelioration of cold injury-induced cortical brain edema formation by selective endothelin ETB receptor antagonists in mice.

    Science.gov (United States)

    Michinaga, Shotaro; Nagase, Marina; Matsuyama, Emi; Yamanaka, Daisuke; Seno, Naoki; Fuka, Mayu; Yamamoto, Yui; Koyama, Yutaka

    2014-01-01

    Brain edema is a potentially fatal pathological condition that often occurs in stroke and head trauma. Following brain insults, endothelins (ETs) are increased and promote several pathophysiological responses. This study examined the effects of ETB antagonists on brain edema formation and disruption of the blood-brain barrier in a mouse cold injury model (Five- to six-week-old male ddY mice). Cold injury increased the water content of the injured cerebrum, and promoted extravasation of both Evans blue and endogenous albumin. In the injury area, expression of prepro-ET-1 mRNA and ET-1 peptide increased. Intracerebroventricular (ICV) administration of BQ788 (ETB antagonist), IRL-2500 (ETB antagonist), or FR139317 (ETA antagonist) prior to cold injury significantly attenuated the increase in brain water content. Bolus administration of BQ788, IRL-2500, or FR139317 also inhibited the cold injury-induced extravasation of Evans blue and albumin. Repeated administration of BQ788 and IRL-2500 beginning at 24 h after cold injury attenuated both the increase in brain water content and extravasation of markers. In contrast, FR139317 had no effect on edema formation when administrated after cold injury. Cold injury stimulated induction of glial fibrillary acidic protein-positive reactive astrocytes in the injured cerebrum. Induction of reactive astrocytes after cold injury was attenuated by ICV administration of BQ788 or IRL-2500. These results suggest that ETB receptor antagonists may be an effective approach to ameliorate brain edema formation following brain insults.

  18. Anti-obesity effects of the combined administration of CB1 receptor antagonist rimonabant and melanin-concentrating hormone antagonist SNAP-94847 in diet-induced obese mice.

    Science.gov (United States)

    Verty, A N A; Lockie, S H; Stefanidis, A; Oldfield, B J

    2013-02-01

    Current anti-obesity monotherapies have proven only marginally effective and are often accompanied by adverse side effects. The cannabinoid 1 (CB1) receptor antagonist rimonabant, while effective at producing weight loss, has been discontinued from clinical use owing to increased incidence of depression. This study investigates the interaction between the cannabinoid and melanin-concentrating hormone (MCH) systems in food intake, body weight control, and mood. Lean male C57BL/6 mice were injected i.p. with rimonabant (0.0, 0.03, 0.3 and 3.0 mg kg(-1)) or the MCH1-R antagonist SNAP-94847 (0.0, 1.0, 5.0 and 10.0 mg kg(-1)) to establish dose response parameters for each drug. Diet-induced obese (DIO) mice were given either vehicle, sub-threshold dose of rimonabant and SNAP-94847 alone or in combination. Impact on behavioral outcomes, food intake, body weight, plasma metabolites and expression of key metabolic proteins in the brown adipose tissue (BAT) and white adipose tissue (WAT) were measured. The high doses of rimonabant and SNAP-94847 produced a reduction in food intake after 2 and 24 h. Combining sub-threshold doses of rimonabant and SNAP-94847 produced a significantly greater loss of body weight in DIO mice compared with vehicle and monotherapies. In addition, combining sub effective doses of these drugs led to a shift in markers of thermogenesis in BAT and lipid metabolism in WAT consistent with increased energy expenditure and lipolysis. Furthermore, co-administration of rimonabant and SNAP-94847 produced a transient reduction in food intake, and significantly reduced fat mass and adipocyte size. Importantly, SNAP-94847 significantly attenuated the ability of rimonabant to reduced immobility time in the forced swim test. These results provide proof of principle that combination of rimonabant and a MCH1 receptor antagonist is highly effective in reducing body weight below that achieved by rimonabant and SNAP-94847 monotherapies. In addition, the

  19. Changes in antagonistic activity of lactic acid bacteria induced by their response to technological factors

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    Dovile Jonkuviene

    2015-12-01

    Full Text Available This study examined the changes in antagonistic activity of selected lactic acid bacteria (LAB in response to technological factors used in food production. The antimicrobial activity of 12 selected LAB strains was assessed against the bacterial and fungal strains using the agar well diffusion method. Sodium chloride (NaCl 6.5–8.0%, glucose 20-30% and pH 4.0, pH 8.0 and higher were the most crucial factors in reducing the spectra of the microorganisms antagonized. Heating at 80 °C or 100 °C had a greater negative impact than 63 °C on the antifungal activity of LAB. Freezing at –72 °C eliminated the antifungal activity, or it changed from fungicidal to fungistatic. Although each LAB demonstrated the ability to retain antimicrobial activity induced by various technological factors, Lactococcus lactis 768/5 was superior in retaining high antimicrobial activity against tested indicator strains.

  20. Exercise-induced bronchoconstriction: The effects of montelukast, a leukotriene receptor antagonist

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    James P Kemp

    2009-11-01

    Full Text Available James P KempClinical Professor of Pediatrics, Division of Immunology and Allergy, University of California School of Medicine, San Diego, CA, USAAbstract: Exercise-induced bronchoconstriction (EIB is very common in both patients with asthma and those who are otherwise thought to be normal. The intensity of exercise as well as the type of exercise is important in producing symptoms. This may make some types of exercise such as swimming more suitable and extended running more difficult for patients with this condition. A better understanding of EIB will allow the physician to direct the patient towards a type of exercise and medications that can result in a more active lifestyle without the same concern for resulting symptoms. This is especially important for schoolchildren who are usually enrolled in physical education classes and elite athletes who may desire to participate in competitive sports. Fortunately several medications (short- and long-acting β2-agonists, cromolyn, nedocromil, inhaled corticosteroids, and more recently leukotriene modifiers have been shown to be effective in preventing or attenuating the effects of exercise in many patients. In addition, inhaled β2-agonists have been shown to quickly reverse the airway obstruction that develops in patients and continue to be the reliever medications of choice. Inhaled corticosteroids are increasingly being recommended as regular therapy now that the role of inflammation and airway injury has been identified in EIB. With the discovery that there is a release of mediators such as histamine and leukotrienes from cells in the airway following exercise with resulting airway obstruction in susceptible individuals, interest has turned to attenuating their effects with mediator antagonists especially those that block the effects of leukotrienes. Studies with an oral leukotriene antagonist, montelukast, have shown beneficial effects in adults and children aged as young as 6 years with EIB

  1. Development of a peptidomimetic antagonist of neuropeptide FF receptors for the prevention of opioid-induced hyperalgesia.

    Science.gov (United States)

    Bihel, Frédéric; Humbert, Jean-Paul; Schneider, Séverine; Bertin, Isabelle; Wagner, Patrick; Schmitt, Martine; Laboureyras, Emilie; Petit-Demoulière, Benoît; Schneider, Elodie; Mollereau, Catherine; Simonnet, Guy; Simonin, Frédéric; Bourguignon, Jean-Jacques

    2015-03-18

    Through the development of a new class of unnatural ornithine derivatives as bioisosteres of arginine, we have designed an orally active peptidomimetic antagonist of neuropeptide FF receptors (NPFFR). Systemic low-dose administration of this compound to rats blocked opioid-induced hyperalgesia, without any apparent side-effects. Interestingly, we also observed that this compound potentiated opioid-induced analgesia. This unnatural ornithine derivative provides a novel therapeutic approach for both improving analgesia and reducing hyperalgesia induced by opioids in patients being treated for chronic pain.

  2. Prevention of chemotherapy-induced nausea: the role of neurokinin-1 (NK1) receptor antagonists.

    Science.gov (United States)

    Bošnjak, Snežana M; Gralla, Richard J; Schwartzberg, Lee

    2017-05-01

    Chemotherapy-induced nausea (CIN) has a significant negative impact on the quality of life of cancer patients. The use of 5-hydroxytryptamine-3 (5-HT 3 ) receptor antagonists (RAs) has reduced the risk of vomiting, but (except for palonosetron) their effect on nausea, especially delayed nausea, is limited. This article reviews the role of NK 1 RAs when combined with 5-HT 3 RA-dexamethasone in CIN prophylaxis. Aprepitant has not shown consistent superiority over a two-drug (ondansetron-dexamethasone) combination in nausea control after cisplatin- or anthracycline-cyclophosphamide (AC)-based highly emetogenic chemotherapy (HEC). Recently, dexamethasone and dexamethasone-metoclopramide were demonstrated to be non-inferior to aprepitant and aprepitant-dexamethasone, respectively, for the control of delayed nausea after HEC (AC/cisplatin), and are now recognized in the guidelines. The potential impact of the new NK 1 RAs rolapitant and netupitant (oral fixed combination with palonosetron, as NEPA) in CIN prophylaxis is discussed. While the clinical significance of the effect on nausea of the rolapitant-granisetron-dexamethasone combination after cisplatin is not conclusive, rolapitant addition showed no improvement in nausea prophylaxis after AC or moderately emetogenic chemotherapy (MEC). NEPA was superior to palonosetron in the control of nausea after HEC (AC/cisplatin). Moreover, the efficacy of NEPA in nausea control was maintained over multiple cycles of HEC/MEC. Recently, NK 1 RAs have been challenged by olanzapine, with olanzapine showing superior efficacy in nausea prevention after HEC. Fixed antiemetic combinations (such as NEPA) or new antiemetics with a long half-life that may be given once per chemotherapy cycle (rolapitant or NEPA) may improve patient compliance with antiemetic treatment.

  3. The functional antagonist Met-RANTES: a modified agonist that induces differential CCR5 trafficking.

    Science.gov (United States)

    Kiss, Debra L; Longden, James; Fechner, Gregory A; Avery, Vicky M

    2009-01-01

    CC chemokine receptor 5 (CCR5) is a pro-inflammatory chemokine receptor that is expressed on cells of the immune system, and specializes in cell migration in response to inflammation and tissue damage. Due to its key role in cell communication and migration, this receptor is involved in various inflammatory and autoimmune diseases, in addition to HIV infection. Met-RANTES is a modified CCR5 ligand that has previously been shown to antagonize CCR5 activation and function in response to its natural ligands in vitro. In vivo, Met-RANTES is able to reduce inflammation in models of induced inflammatory and autoimmune diseases. However, due to the fact that Met-RANTES is also capable of partial agonist activity regarding receptor signaling and internalization, it is clear that Met-RANTES does not function as a conventional receptor antagonist. To further elucidate the effect of Met-RANTES on CCR5, receptor trafficking was investigated in a CHO-CCR5-GFP cell line using the Opera confocal plate reader. The internalization response of CCR5 was quantified, and showed that Met-RANTES internalized CCR5 in a slower, less potent manner than the agonists CCL3 and CCL5. Fluorescent organelle labeling and live cell imaging showed CCL3 and CCL5 caused CCR5 to traffic through sorting endosomes, recycling endosomes and the Golgi apparatus. In contrast, Met-RANTES caused CCR5 to traffic through sorting endosomes and the Golgi apparatus in a manner that was independent of recycling endosomes. As receptor trafficking impacts on cell surface expression and the ability of the receptor to respond to more ligand, this information may indicate an alternative regulation of CCR5 by Met-RANTES that allows the modified ligand to reduce inflammation through stimulation of a pro-inflammatory receptor.

  4. Dantrolene: A Selective Ryanodine Receptor Antagonist, Protects Against Pentylenetetrazole-Induced Seizure in Mice

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    Mojtaba Keshavarz

    2016-10-01

    Full Text Available Ryanodine receptor abnormalities has implicated in the generation and maintenance of seizure. Dantrolene, a selective ryanodine receptor antagonist, may be a potential drug for the prevention of seizure. Therefore, we aimed to clarify the protective effects of dantrolene against pentylenetetrazole seizure in mice. Male albino mice were received an intra-peritoneal injection of pentylenetetrazole (80 mg/kg in seven separate groups (n=8. We used dantrolene (10,20 and 40 mg/kg, caffeine (200 mg/kg, dantrolene (40 mg/kg + caffeine (200 mg/kg, diazepam (5 mg/kg as a positive control and vehicle 30 minutes before the injection of pentylenetetrazole. Then, we registered the latency time of the first seizure, the severity of seizures and the incidence of seizure and death. Kruskal-Wallis test followed by Mann-Whitney and Fisher’s exact test were used to analyze the data. Dantrolene (10,20 and 40 mg/kg significantly increased the latency time for the first seizure. Furthermore, dantrolene (20 and 40 mg/kg, but not 10 mg/kg attenuated the severity of seizures in comparison to the vehicle group. Moreover, dantrolene only at the dose of 40 mg/kg prevented from tonic-clonic seizure and death in comparison to the vehicle group. In contrast, the addition of caffeine abolished the protective effects of dantrolene on the tonic-clonic seizure/death and inhibited the beneficial effects of dantrolene on the severity of pentylenetetrazol seizures. The acute dantrolene administration produced an anticonvulsant effect in the pentylenetetrazole-induced seizure. Moreover, caffeine prevented from dantrolene anticonvulsant effects. These results may imply about ryanodine receptors and intracellular calcium roles in the generation and control of pentylenetetrazole seizure.

  5. Effect of the endothelin receptor antagonist tezosentan on alpha-naphthylthiourea-induced lung injury in rats

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    Figen Atalay

    2012-02-01

    Full Text Available Acute lung injury is an inflammatory syndrome that increases the permeability of the blood-gas barrier, resulting in high morbidity and mortality. Despite intensive research, treatment options remain limited. We investigated the protective efficacy of tezosentan, a novel, dual endothelin receptor antagonist, in an experimental model of alpha-naphthylthiourea (ANTU-induced acute lung injury in rats. ANTU was intraperitoneally (i.p. injected into rats at a dose of 10 mg/kg. Tezosentan was injected 30 minutes before ANTU was subcutaneously (s.c. injected at doses of 2, 10, or 30 mg/kg, 60 minutes before ANTU was injected at doses of 2, 10, or 30 mg/kg (i.p., and 90 minutes before ANTU at a dose of 10 mg/kg (i.p.. Four hours later, the lung weight/body weight (LW/BW ratio and pleural effusion (PE were measured. When injected 30 minutes before ANTU at doses of 2, 10, or 30 mg/kg (s.c., tezosentan had no effect on lung pathology. When injected 60 minutes before ANTU at doses of 2, 10, or 30 mg/kg (i.p. or 90 minutes before ANTU (10 mg/kg, i.p., tezosentan significantly decreased the PE/BW ratio and had a prophylactic effect on PE formation at all doses. Therefore, tezosentan may attenuate lung injury. Furthermore, its acute and inhibitory effects on fluid accumulation were more effective in the pleural cavity than in the interstitial compartment in this experimental model.

  6. Efficacy of glutamate receptor antagonists in the management of functional disorders in cytotoxic brain oedema induced by hexachlorophene.

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    Häntzschel, A; Andreas, K

    1998-02-01

    The hexachlorophene-induced cytotoxic brain oedema is an experimental model of brain damage, suitable for testing cerebroprotective substances (Andreas 1993). In order to examine whether glutamate receptors are involved in mediating functional disorders due to neurotoxic brain damage, we have studied the protective effects of several competitive and non-competitive antagonists using adult male Wistar rats in a simple "ladder-test" for assessing coordinative motor behaviour. Hexachlorophene-induced brain damage was verified by histological examination of the cerebellum with vacuolation of white matter, astrocyte hypertrophy and astrocyte proliferation taken as signs of neurotoxic injury. The non-competitive N-methyl-D-aspartate (NMDA) antagonist dizocilpine maleate (MK-801) decreased the motor disturbance on the first and second day of the "ladder-test" when applied in the doses 0.1 mg/kg and 0.2 mg/kg intraperitoneally for 3 weeks during the hexachlorophene treatment. Acute MK-801 administration (0.1 mg/kg intraperitoneally) after 3 weeks hexachlorophene exposure improved the coordinative motor response only on the first day. When testing the competitive NMDA receptor antagonist 2-amino-5-phosphonopentanoic acid (AP-5) in the dose 1.0 mg/kg intraperitoneally the motor disturbance was lowered significantly earlier than in spontaneous remission. Similar effects were observed with 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) in the dose of 0.8 mg/kg intraperitoneally, an antagonist interacting both with the strychnine-insensitive binding site for glycine within the NMDA receptor complex and with the kainate(+/-)-alpha-amino-3-hydroxy-5-methylisoxazole-4-propionic acid (AMPA) receptor complex. Concurrent MK-801 administration decreased the vacuolation of white matter. The results suggest that NMDA receptors and non-NMDA receptors are involved in development of functional disorders induced by hexachlorophene.

  7. Ultra-low dose cannabinoid antagonist AM251 enhances cannabinoid anticonvulsant effects in the pentylenetetrazole-induced seizure in mice.

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    Gholizadeh, Shervin; Shafaroodi, Hamed; Ghasemi, Mehdi; Bahremand, Arash; Sharifzadeh, Mohammad; Dehpour, Ahmad Reza

    2007-11-01

    Several lines of evidence suggest that cannabinoid compounds are anticonvulsant since they have inhibitory effects at micromolar doses, which are mediated by activated receptors coupling to Gi/o proteins. Surprisingly, both the analgesic and anticonvulsant effects of opioids are enhanced by ultra-low doses (nanomolar to picomolar) of the opioid antagonist naltrexone and as opioid and cannabinoid systems interact, it has been shown that ultra-low dose naltrexone also enhances cannabinoid-induced antinociception. However, regarding the seizure modulating properties of both classes of receptors this study investigated whether ultra-low dose cannabinoid antagonist AM251 influences cannabinoid anticonvulsant effects. The clonic seizure threshold (CST) was tested in separate groups of male NMRI mice following injection of vehicle, the cannabinoid selective agonist arachidonyl-2-chloroethylamide (ACEA) and ultra-low doses of the cannabinoid CB1 antagonist AM251 and a combination of ACEA and AM251 doses in a model of clonic seizure induced by pentylenetetrazole (PTZ). Systemic administration of ultra-low doses of AM251 (10 fg/kg-100 ng/kg) significantly potentiated the anticonvulsant effect of ACEA at 0.5 and 1 mg/kg. Moreover, inhibition of cannabinoid induced excitatory signaling by AM251 (100 pg/kg) unmasked a strong anticonvulsant effect for very low doses of ACEA (100 ng/kg-100 microg/kg), suggesting that a presumed inhibitory component of cannabinoid receptor signaling can exert strong seizure-protective effects even at very low levels of cannabinoid receptor activation. A similar potentiation by AM251 (100 pg/kg and 1 ng/kg) of anticonvulsant effects of non-effective dose of ACEA (0.5 and 1 mg/kg) was also observed in the generalized tonic-clonic model of seizure. The present data suggest that ultra-low doses of cannabinoid receptor antagonists may provide a potent strategy to modulate seizure susceptibility, especially in conjunction with very low doses of

  8. Casopitant: a novel NK1-receptor antagonist in the prevention of chemotherapy-induced nausea and vomiting

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    Christina Ruhlmann

    2009-05-01

    Full Text Available Christina Ruhlmann, Jørn HerrstedtOdense University Hospital, Department of Oncology, Odense, DenmarkAbstract: Chemotherapy-induced nausea and vomiting (CINV are among the most feared and distressing symptoms experienced by patients with cancer. The knowledge of the pathogenesis and neuropharmacology of CINV has expanded enormously over the last decades, the most significant discoveries being the role of 5-hydroxytryptamine (5-HT3- and neurokinin (NK1 receptors in the emetic reflex arch. This has led to the development of two new classes of antiemetics acting as highly selective antagonists at one of these receptors. These drugs have had a huge impact in the protection from chemotherapy-induced vomiting, whereas the effect on nausea seems to be limited. The first NK1 receptor antagonist, aprepitant, became clinically available in 2003, and casopitant, the second in this class of antiemetics, has now completed phase III trials. This review delineates the properties and clinical use of casopitant in the prevention of CINV.Keywords: casopitant, GW679769, NK1 receptor antagonist, chemotherapy, emesis

  9. Muscarinic cholinergic receptor antagonists in the VTA and RMTg have opposite effects on morphine-induced locomotion in mice.

    Science.gov (United States)

    Steidl, Stephan; Dhillon, Ekamjeet S; Sharma, Natasha; Ludwig, Jessica

    2017-04-14

    The ventral tegmental area (VTA) and the rostromedial tegmental nucleus (RMTg) each contribute to opiate reward and each receive inputs from the laterodorsal tegmental and pedunculopontine tegmental nuclei, the two principle brainstem cholinergic cell groups. We compared the contributions of VTA or RMTg muscarinic cholinergic receptors to locomotion induced by morphine infusions into the same sites. VTA co-infusion of atropine completely blocked VTA morphine-induced locomotion providing additional support for the important role of VTA muscarinic cholinergic receptors in the stimulant effects of opiates. By contrast, RMTg co-infusion of atropine increased RMTg morphine-induced locomotion. Furthermore, RMTg co-infusion of the M3-selective antagonist 4-DAMP, but not the M4-selective antagonist Tropicamide, strongly increased RMTg morphine-induced locomotion. RMTg infusions of 4-DAMP, but not of Tropicamide, by themselves strongly increased drug-free locomotion. Muscarinic cholinergic receptors in the RMTg thus also contribute to the stimulant effects of morphine, but in a way opposite to those in VTA. We suggest that the net effect of endogenous cholinergic input to the RMTg on drug-free and on RMTg morphine-induced locomotion is inhibitory. Copyright © 2017 Elsevier B.V. All rights reserved.

  10. Bacterial antagonists of fungal pathogens also control root-knot nematodes by induced systemic resistance of tomato plants.

    Science.gov (United States)

    Adam, Mohamed; Heuer, Holger; Hallmann, Johannes

    2014-01-01

    The potential of bacterial antagonists of fungal pathogens to control the root-knot nematode Meloidogyne incognita was investigated under greenhouse conditions. Treatment of tomato seeds with several strains significantly reduced the numbers of galls and egg masses compared with the untreated control. Best performed Bacillus subtilis isolates Sb4-23, Mc5-Re2, and Mc2-Re2, which were further studied for their mode of action with regard to direct effects by bacterial metabolites or repellents, and plant mediated effects. Drenching of soil with culture supernatants significantly reduced the number of egg masses produced by M. incognita on tomato by up to 62% compared to the control without culture supernatant. Repellence of juveniles by the antagonists was shown in a linked twin-pot set-up, where a majority of juveniles penetrated roots on the side without inoculated antagonists. All tested biocontrol strains induced systemic resistance against M. incognita in tomato, as revealed in a split-root system where the bacteria and the nematodes were inoculated at spatially separated roots of the same plant. This reduced the production of egg masses by up to 51%, while inoculation of bacteria and nematodes in the same pot had only a minor additive effect on suppression of M. incognita compared to induced systemic resistance alone. Therefore, the plant mediated effect was the major reason for antagonism rather than direct mechanisms. In conclusion, the bacteria known for their antagonistic potential against fungal pathogens also suppressed M. incognita. Such "multi-purpose" bacteria might provide new options for control strategies, especially with respect to nematode-fungus disease complexes that cause synergistic yield losses.

  11. A Meta-Analysis of Adenosine A2A Receptor Antagonists on Levodopa-Induced Dyskinesia In Vivo

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    Wen-Wen Wang

    2017-12-01

    Full Text Available BackgroundLong-term use of levodopa (l-dopa is inevitably complicated with highly disabling fluctuations and drug-induced dyskinesias, which pose major challenges to the existing drug therapy of Parkinson’s disease.MethodsIn this study, we conducted a systematic review and meta-analysis to assess the efficacy of A2A receptor antagonists on reducing l-dopa-induced dyskinesias (LID.ResultsNine studies with a total of 152 animals were included in this meta-analysis. Total abnormal involuntary movements (AIM score, locomotor activity, and motor disability were reported as outcome measures in 5, 5, and 3 studies, respectively. Combined standardized mean difference (SMD estimates were calculated using a random-effects model. We pooled the whole data and found that, when compared to l-dopa alone, A2A receptor antagonists plus l-dopa treatment showed no effect on locomotor activity (SMD −0.00, 95% confidence interval (CI: −2.52 to 2.52, p = 1.0, superiority in improvement of motor disability (SMD −5.06, 95% CI: −9.25 to −0.87, p = 0.02 and more effective in control of AIM (SMD −1.82, 95% CI: −3.38 to −0.25, p = 0.02.ConclusionTo sum up, these results demonstrated that A2A receptor antagonists appear to have efficacy in animal models of LID. However, large randomized clinical trials testing the effects of A2A receptor antagonists in LID patients are always warranted.

  12. Modulation of bleomycin-induced lung fibrosis by pegylated hyaluronidase and dopamine receptor antagonist in mice.

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    Evgenii Germanovich Skurikhin

    Full Text Available Hyaluronidases are groups of enzymes that degrade hyaluronic acid (HA. To stop enzymatic hydrolysis we modified testicular hyaluronidase (HYAL by activated polyethylene oxide with the help of electron-beam synthesis. As a result we received pegylated hyaluronidase (pegHYAL. Spiperone is a selective D2 dopamine receptor antagonist. It was demonstrated on the model of a single bleomycin damage of alveolar epithelium that during the inflammatory phase monotherapy by pegHYAL or spiperone reduced the populations of hematopoietic stem /progenitor cells in the lung parenchyma. PegHYAL also reduced the levels of transforming growth factor (TGF-β, interleukin (IL-1β, tumor necrosis factor (TNF-α in the serum and lungs, while spiperone reduced the level of the serum IL-1β. Polytherapy by spiperone and pegHYAL caused the increase of the quantity of hematopoietic stem/ progenitor cells in the lungs. Such an influx of blood cell precursors was observed on the background of considerable fall level of TGF-β and the increase level of TNF-α in the serum and lungs. These results show pegHYAL reduced the bleomycin-induced fibrosis reaction (production and accumulation of collagen in the lung parenchyma. This effect was observed at a single and repetitive bleomycin damage of alveolar epithelium, the antifibrotic activity of pegHYAL surpassing the activity of testicular HYAL. The antifibrotic effect of pegHYAL is enhanced by an additional instillation of spiperone. Therapy by pegHYAL causes the flow of CD31‒ CD34‒ CD45‒ CD44+ CD73+ CD90+ CD106+-cells into the fibrous lungs. These cells are incapable of differentiating into fibroblast cells. Spiperone instillation separately or together with pegHYAL reduced the MSC-like cells considerably. These data enable us to assume, that pegHYAL is a new and promising instrument both for preventive and therapy of toxic pneumofibrosis. The blockage of D2 dopamine receptors with the following change of hyaluronan

  13. βCCT, AN ANTAGONIST SELECTIVE FOR α1 GABAA RECEPTORS, REVERSES DIAZEPAM WITHDRAWAL-INDUCED ANXIETY IN RATS

    Science.gov (United States)

    Divljaković, Jovana; Milić, Marija; Namjoshi, Ojas A.; Tiruveedhula, Veera V.; Timić, Tamara; Cook, James M.; Savić, Miroslav M.

    2012-01-01

    The abrupt discontinuation of prolonged benzodiazepine treatment elicits a withdrawal syndrome with increased anxiety as a major symptom. The neural mechanisms underlying benzodiazepine physical dependence are still insufficiently understood. Flumazenil, the non-selective antagonist of the benzodiazepine binding site of GABAA receptors was capable of preventing and reversing the increased anxiety during benzodiazepine withdrawal in animals and humans in some, but not all studies. On the other hand, a number of data suggest that GABAA receptors containing α1 subunits are critically involved in processes developing during prolonged use of benzodiazepines, such are tolerance to sedative effects, liability to physical dependence and addiction. Hence, we investigated in the elevated plus maze the level of anxiety 24 h following 21 days of diazepam treatment and the influence of flumazenil or a preferential α1-subunit selective antagonist βCCt on diazepam withdrawal syndrome in rats. Abrupt cessation of protracted once-daily intraperitoneal administration of 2 mg/kg diazepam induced a withdrawal syndrome, measured by increased anxiety-like behavior in the elevated plus maze 24 h after treatment cessation. Acute challenge with either flumazenil (10 mg/kg) or βCCt (1.25, 5 and 20 mg/kg) alleviated the diazepam withdrawal-induced anxiety. Moreover, both antagonists induced an anxiolytic-like response close, though not identical, to that seen with acute administration of diazepam. These findings imply that the mechanism by which antagonism at GABAA receptors may reverse the withdrawal-induced anxiety involves the α1 subunit and prompt further studies aimed at linking the changes in behavior with possible adaptive changes in subunit expression and function of GABAA receptors. PMID:23149168

  14. PAR1 antagonists inhibit thrombin-induced platelet activation whilst leaving the PAR4-mediated response intact.

    Science.gov (United States)

    Judge, Heather M; Jennings, Lisa K; Moliterno, David J; Hord, Edward; Ecob, Rosemary; Tricoci, Pierluigi; Rorick, Tyrus; Kotha, Jayaprakash; Storey, Robert F

    2015-01-01

    Thrombin-induced platelet activation is initiated by PAR1 and PAR4 receptors. Vorapaxar, a PAR1 antagonist, has been assessed in patients with acute coronary syndromes (ACS) and stable atherosclerotic disease in addition to standard-of-care treatment. In clinical trials, vorapaxar has been observed to reduce the frequency of ischaemic events in some subgroups though in others has increased the frequency of bleeding events. Among patients undergoing CABG surgery, which is associated with excess thrombin generation, bleeding was not increased. The aim of these studies was to investigate the effects of selective PAR1 antagonism on thrombin-induced platelet activation in patients receiving vorapaxar or placebo in the TRACER trial and to explore the roles of PAR1 and PAR4 in thrombin-induced platelet activation in healthy volunteers. ACS patients receiving vorapaxar or placebo in the TRACER trial were studied at baseline and 4 hours, 1 and 4 months during drug administration. Thrombin-induced calcium mobilisation in platelet-rich plasma was assessed by flow cytometry. In vitro studies were performed in healthy volunteers using the PAR1 antagonist SCH79797 or PAR4 receptor desensitisation. Vorapaxar treatment significantly inhibited thrombin-induced calcium mobilisation, leaving a residual, delayed response. These findings were consistent with calcium mobilisation mediated via the PAR4 receptor and were reproduced in vitro using SCH79797. PAR4 receptor desensitization, in combination with SCH79797, completely inhibited thrombin-induced calcium mobilisation confirming that the residual calcium mobilisation was mediated via PAR4. In conclusion vorapaxar selectively antagonises the PAR1-mediated component of thrombin-induced platelet activation, leaving the PAR4-mediated response intact, which may explain why vorapaxar is well tolerated in patients undergoing CABG surgery since higher thrombin levels in this setting may override the effects of PAR1 antagonism through PAR4

  15. Stress-induced visceral hypersensitivity in maternally separated rats can be reversed by peripherally restricted histamine-1-receptor antagonists.

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    Oana I Stanisor

    Full Text Available BACKGROUND: The histamine-1 receptor (H1R antagonist ketotifen increased the threshold of discomfort in hypersensitive IBS patients. The use of peripherally restricted and more selective H1R antagonists may further improve treatment possibilities. We examined the use of fexofenadine and ebastine to reverse post-stress visceral hypersensitivity in maternally separated rats. METHODS: The visceromotor response to colonic distension was assessed in adult maternally separated and nonhandled rats pre- and 24 hours post water avoidance. Subsequently rats were treated with vehicle alone or different dosages of fexofenadine (1.8 and 18 mg/kg or ebastine (0.1 and 1.0 mg/kg and re-evaluated. Colonic tissue was collected to assess relative RMCP-2 and occludin expression levels by Western blot and histamine-1 receptor by RT-qPCR. β-hexosaminidase release by RBL-2H3 cells was used to establish possible mast cell stabilizing properties of the antagonists. KEY RESULTS: Water avoidance only induced enhanced response to distension in maternally separated rats. This response was reversed by 1.8 and 18 mg/kg fexofenadine. Reversal was also obtained by 1.0 but not 0.1 mg/kg ebastine. RMCP-2 expression levels were comparable in these two ebastine treatment groups but occludin was significantly higher in 1.0 mg/kg treated rats. There were no differences in histamine-1 receptor expression between nonhandled and maternally separated rats. Fexofenadine but not ebastine showed mast cell stabilizing quality. CONCLUSIONS: Our results indicate that the peripherally restricted 2(nd generation H1-receptor antagonists fexofenadine and ebastine are capable of reversing post stress visceral hypersensitivity in rat. These data justify future IBS patient trials with these well tolerated compounds.

  16. A selective, non-peptide CRF receptor 1 antagonist prevents sodium lactate-induced acute panic-like responses.

    Science.gov (United States)

    Shekhar, Anantha; Johnson, Philip L; Fitz, Stephanie D; Nakazato, Atsuro; Chaki, Shigeyuki; Steckler, Thomas; Schmidt, Mark

    2011-04-01

    Corticotropin releasing factor (CRF) is implicated in a variety of stress-related disorders such as depression and anxiety, and blocking CRF receptors is a putative strategy for treating such disorders. Using a well-studied animal model of panic, we tested the efficacy of JNJ19567470/CRA5626, a selective, non-peptidergic CRF type 1 receptor (CRF1) antagonist (3, 10 and 40 mg/kg intraperitoneal injection), in preventing the sodium lactate (NaLac)-induced panic-like behavioural and cardiovascular responses. Adult male rats with chronic reduction of GABA levels (by inhibition of GABA synthesis with l-allyglycine, a glutamic acid decarboxylase inhibitor) in the dorsomedial/perifornical hypothalamus are highly anxious and exhibit physiological and behavioural responses to intravenous NaLac infusions similar to patients with panic disorder. These 'panic-prone' rats pre-treated with vehicle injections displayed NaLac-induced increases in autonomic responses (i.e. tachycardia and hypertensive responses), anxiety-like behaviour in the social interaction test, and flight-like increases in locomotor activity. However, systemically injecting such panic-prone rats with the highest dose of CRF1 receptor antagonist prior to NaLac infusions blocked all NaLac-induced behaviour and cardiovascular responses. These data suggest that selective CRF1 receptor antagonists could be a novel target for developing anti-panic drugs that are as effective as benzodiazepines in acute treatment of a panic attack without the deleterious side-effects (e.g. sedation and cognitive impairment) associated with benzodiazepines.

  17. Neuroendocrine and sympathetic responses to an orexin receptor antagonist, SB-649868, and alprazolam following insulin-induced hypoglycemia in humans.

    Science.gov (United States)

    Patel, Ameera X; Miller, Sam R; Nathan, Pradeep J; Kanakaraj, Ponmani; Napolitano, Antonella; Lawrence, Philip; Koch, Annelize; Bullmore, Edward T

    2014-10-01

    The orexin-hypocretin system is important for translating peripheral metabolic signals and central neuronal inputs to a diverse range of behaviors, from feeding, motivation and arousal, to sleep and wakefulness. Orexin signaling is thus an exciting potential therapeutic target for disorders of sleep, feeding, addiction, and stress. Here, we investigated the low dose pharmacology of orexin receptor antagonist, SB-649868, on neuroendocrine, sympathetic nervous system, and behavioral responses to insulin-induced hypoglycemic stress, in 24 healthy male subjects (aged 18-45 years; BMI 19.0-25.9 kg/m(2)), using a randomized, double-blind, placebo-controlled, within-subject crossover design. Alprazolam, a licensed benzodiazepine anxiolytic, was used as a positive comparator, as it has previously been validated using the insulin tolerance test (ITT) model in humans. Of the primary endpoints, ITT induced defined increases in pulse rate, plasma cortisol, and adrenocorticotropic hormone in the placebo condition, but these responses were not significantly impacted by alprazolam or SB-649868 pre-treatment. Of the secondary endpoints, ITT induced a defined increase in plasma concentrations of adrenaline, noradrenaline, growth hormone (GH), and prolactin in the placebo condition. Alprazolam pre-treatment significantly reduced the GH response to ITT (p neuroendocrine or sympathetic nervous systems, but could not be validated for studying low dose orexin antagonist activity.

  18. "Interaction of different doses of Aspartame with Morphine-induced antinociception in the presence of MK-801, a NMDA antagonist "

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    Abdollahi M

    2002-07-01

    Full Text Available This study was designed to investigate the relative role of sweetness and comparative effects of different taste sensation of the non - caloric sweetener , aspartame on pain and its interaction with MK - 80] as a non - selective MMDA antagonist by formalin - test in mice. The formalin - test was chosen because it measures the response to a long - lasting nociceptive stimulus and closely resembles to the clinical pain. Morphine induced a dose dependent antinociception in the early and late phases of formalin test. Twelve days pretreatment of animals by aspartame ( 0.08% , 0.16% , 0.32% significantly potentiated morphine - induced (1.5-9 mg/kg analgesia in the early phase but significantly antagonized its analgesic effect in the late phase, dose dependently. Aspartame (0.16% alone showed a reduction in pain response . Naloxone (0.4 mg/kg significantly antagonized the antinociceptive effect of morphine in the presence of aspartame (0-0.32% in the early phase. Increasing the dose of aspartame decreased effects of naloxone. MK-801 (0.1 mg/kg as an N- Methyl - D - Aspartate (NMDA antagonist significantly potentiated the effect of aspartame on morphine - induced antinociception in the early phase. In the late phase, naloxone (0.4 mg/kg increased pain response but MK- 801 (0.1 mg/kg induced anti-inflammatory effect significantly. Treatment of animals with MK- 801 alone, significantly induced analgesia in both phases of formalin - test. This effect was potentiated with aspartame dose - dependently. Possible interaction of aspartame with NMDA receptors and its role to facilitate endogenous opioid system are proposed mechanisms of aspartame in modulating morphine - induced antinociception. Furthermore, the resulting association between morphine and aspartame chronic consumption may be explained as an interactive action rather than simple dose combination of both drugs.

  19. Netupitant, a Potent and Highly Selective NK1 Receptor Antagonist, Alleviates Acetic Acid-Induced Bladder Overactivity in Anesthetized Guinea-Pigs

    OpenAIRE

    Palea, Stefano; Guilloteau, V?ronique; Rekik, Mo?z; Lovati, Emanuela; Guerard, Marc; Guardia, Maria-Alba; Lluel, Philippe; Pietra, Claudio; Yoshiyama, Mitsuharu

    2016-01-01

    Introduction. Tachykinins potently contract the isolated urinary bladder from a number of animal species and play an important role in the regulation of the micturition reflex. On the guinea-pig isolated urinary bladder we examined the effects of a new potent and selective NK1 receptor antagonist (netupitant) on the contractions induced by a selective NK1 receptor agonist, SP-methylester (SP-OMe). Moreover, the effects of netupitant and another selective NK1 antagonist (L-733,060) were studie...

  20. CGRP receptors mediating CGRP-, adrenomedullin- and amylin-induced relaxation in porcine coronary arteries. Characterization with 'Compound 1' (WO98/11128), a non-peptide antagonist

    DEFF Research Database (Denmark)

    Hasbak, P; Sams, A; Schifter, S

    2001-01-01

    . The partial porcine mRNA sequences shared 82 - 92% nucleotide identity with human sequences. 3. The human peptides alphaCGRP, betaCGRP, AM and amylin induced relaxation with pEC(50) values of 8.1, 8.1, 6.7 and 6.1 M respectively. 4. The antagonistic properties of a novel non-peptide CGRP antagonist 'Compound...

  1. Rimonabant, a selective cannabinoid1 receptor antagonist, protects against light-induced retinal degeneration in vitro and in vivo.

    Science.gov (United States)

    Imamura, Tomoyo; Tsuruma, Kazuhiro; Inoue, Yuki; Otsuka, Tomohiro; Ohno, Yuta; Ogami, Shiho; Yamane, Shinsaku; Shimazawa, Masamitsu; Hara, Hideaki

    2017-05-15

    The endocannabinoid system is involved in some neurodegenerative diseases such as Alzheimer's disease. An endogenous constellation of proteins related to cannabinoid 1 receptor signaling, including free fatty acids, diacylglycerol lipase, and N-acylethanolamine-hydrolyzing acid amidase, are localized in the murine retina. Moreover, the expression levels of endogenous agonists of cannabinoid receptors are changed in the vitreous fluid. However, the role of the endocannabinoid system in the retina, particularly in the light-induced photoreceptor degeneration, remains unknown. Therefore, we investigated involvement of the cannabinoid 1 receptor in light-induced retinal degeneration using in vitro and in vivo models. To evaluate the effect of cannabinoid 1 receptors in light irradiation-induced cell death, the mouse retinal cone-cell line (661W) was treated with a cannabinoid 1 receptor antagonist, rimonabant. Time-dependent changes of expression and localization of retinal cannabinoid 1 receptors were measured using Western blot and immunostaining. Retinal damage was induced in mice by exposure to light, followed by intravitreal injection of rimonabant. Electroretinograms and histologic analyses were performed. Rimonabant suppressed light-induced photoreceptor cell death. Cannabinoid 1 receptor expression was upregulated by light exposure. Treatment with rimonabant improved both a- and b-wave amplitudes and the thickness of the outer nuclear layer. These results suggest that the cannabinoid 1 receptor is involved in light-induced retinal degeneration and it may represent a therapeutic target in the light-induced photoreceptor degeneration related diseases. Copyright © 2017 Elsevier B.V. All rights reserved.

  2. Effects of oral cetirizine, a selective H1 antagonist, on allergen- and exercise-induced bronchoconstriction in subjects with asthma.

    LENUS (Irish Health Repository)

    Gong, H

    1990-03-01

    The protective efficacy of oral cetirizine, a selective and potent H1-receptor antagonist, against the immediate bronchoconstrictive response to allergen inhalation and exercise challenge was evaluated in 16 subjects with stable, predominantly mild asthma. The subjects underwent double-blind, crossover pretreatments in randomized order in two separate protocols with (1) three daily oral doses of 20 mg of cetirizine and placebo, followed by allergen inhalation, and (2) single oral doses of cetirizine (5, 10, and 20 mg), albuterol (4 mg), and placebo, followed by exercise with cold-air inhalation. Cetirizine failed to decrease bronchial sensitivity to inhaled allergen in eight of 10 subjects. Neither cetirizine nor albuterol uniformly inhibited exercise-induced bronchoconstriction. Serum concentrations of cetirizine were consistent with systemic H1-blocking activity. Modest bronchodilation occurred after administration of cetirizine and albuterol before exercise but not after the third dose of cetirizine in the allergen protocol. One subject developed moderate drowsiness during multiple dosing with cetirizine. Thus, cetirizine, in the doses studied, is not uniformly effective in preventing allergen- or exercise-induced bronchoconstriction. Histamine is one of many mediators participating in immediate asthmatic responses, and selective H1 antagonists do not completely block these airway events. However, cetirizine may still clinically benefit some patients with asthma, such as patients with allergic rhinitis or urticaria.

  3. The 5-HT3Receptor Antagonist Ondansetron Attenuates Pancreatic Injury in Cerulein-Induced Acute Pancreatitis Model.

    Science.gov (United States)

    Tsukamoto, Atsushi; Sugimoto, Takuto; Onuki, Yuta; Shinoda, Hajime; Mihara, Taiki; Hori, Masatoshi; Inomata, Tomo

    2017-08-01

    The 5-hydroxytryptamine-3 receptor (5-HT 3 R) antagonist ondansetron has been clinically approved as an anti-emetic agent. Recent findings indicate that ondansetron has anti-inflammatory properties. The aim of the present study was to assess the therapeutic action of ondansetron in cerulein-induced acute pancreatitis model. Male-BALB/c mice were used in the present study. Acute pancreatitis was induced by an hourly injection of cerulein. Ondansetron was administered subcutaneously at a dose of 3 mg/kg. The messenger RNA (mRNA) expression of 5-HT 3 R in pancreatic tissue was assessed with RT-PCR. Plasma amylase, lipase, and interleukin (IL)-6 levels were evaluated. Pancreatic injury was histopathologically graded, and myeloperoxidase (MPO)-positive cells were counted. 5-HT 3 R mRNA was expressed in the pancreas. In acute pancreatitis model mice, amylase, lipase, and IL-6 levels were significantly increased in the blood. With ondansetron treatment, these levels were significantly decreased. Histopathological evaluation revealed that ondansetron attenuated the inflammatory damage in acute pancreatitis. The number of infiltrated neutrophils stained by MPO was decreased by ondansetron treatment. In summary, the 5-HT 3 R antagonist ondansetron attenuated pancreatic injury through its anti-inflammatory action. These findings suggest that ondansetron may potentially be of use for therapy of acute pancreatitis.

  4. The effect of montelukast (MK-0476), a cysteinyl leukotriene receptor antagonist, on allergen-induced airway responses and sputum cell counts in asthma

    NARCIS (Netherlands)

    Diamant, Z.; Grootendorst, D. C.; Veselic-Charvat, M.; Timmers, M. C.; de Smet, M.; Leff, J. A.; Seidenberg, B. C.; Zwinderman, A. H.; Peszek, I.; Sterk, P. J.

    1999-01-01

    Cysteinyl leukotrienes are capable of inducing chemotaxis of eosinophils in vitro and within the airways of animals and humans in vivo. We hypothesized that montelukast (MK-0476), a potent cysLT1 receptor antagonist, would protect against allergen-induced early (EAR) and late (LAR) asthmatic

  5. Intracerebroventricular infusion of the (Pro)renin receptor antagonist PRO20 attenuates deoxycorticosterone acetate-salt-induced hypertension.

    Science.gov (United States)

    Li, Wencheng; Sullivan, Michelle N; Zhang, Sheng; Worker, Caleb J; Xiong, Zhenggang; Speth, Robert C; Feng, Yumei

    2015-02-01

    We previously reported that binding of prorenin to the (pro)renin receptor (PRR) plays a major role in brain angiotensin II formation and the development of deoxycorticosterone acetate (DOCA)-salt hypertension. Here, we designed and developed an antagonistic peptide, PRO20, to block prorenin binding to the PRR. Fluorescently labeled PRO20 bound to both mouse and human brain tissues with dissociation constants of 4.4 and 1.8 nmol/L, respectively. This binding was blocked by coincubation with prorenin and was diminished in brains of neuron-specific PRR-knockout mice, indicating specificity of PRO20 for PRR. In cultured human neuroblastoma cells, PRO20 blocked prorenin-induced calcium influx in a concentration- and AT(1) receptor-dependent manner. Intracerebroventricular infusion of PRO20 dose-dependently inhibited prorenin-induced hypertension in C57Bl6/J mice. Furthermore, acute intracerebroventricular infusion of PRO20 reduced blood pressure in both DOCA-salt and genetically hypertensive mice. Chronic intracerebroventricular infusion of PRO20 attenuated the development of hypertension and the increase in brain hypothalamic angiotensin II levels induced by DOCA-salt. In addition, chronic intracerebroventricular infusion of PRO20 improved autonomic function and spontaneous baroreflex sensitivity in mice treated with DOCA-salt. In summary, PRO20 binds to both mouse and human PRRs and decreases angiotensin II formation and hypertension induced by either prorenin or DOCA-salt. Our findings highlight the value of the novel PRR antagonist, PRO20, as a lead compound for a novel class of antihypertensive agents and as a research tool to establish the validity of brain PRR antagonism as a strategy for treating hypertension. © 2014 American Heart Association, Inc.

  6. Intracerebroventricular Infusion of the (Pro)renin Receptor Antagonist PRO20 Attenuates Deoxycorticosterone Acetate-Salt–Induced Hypertension

    Science.gov (United States)

    Li, Wencheng; Sullivan, Michelle N.; Zhang, Sheng; Worker, Caleb J.; Xiong, Zhenggang; Speth, Robert C.; Feng, Yumei

    2016-01-01

    We previously reported that binding of prorenin to the (pro)renin receptor (PRR) plays a major role in brain angiotensin II formation and the development of deoxycorticosterone acetate (DOCA)-salt hypertension. Here, we designed and developed an antagonistic peptide, PRO20, to block prorenin binding to the PRR. Fluorescently labeled PRO20 bound to both mouse and human brain tissues with dissociation constants of 4.4 and 1.8 nmol/L, respectively. This binding was blocked by coincubation with prorenin and was diminished in brains of neuron-specific PRR-knockout mice, indicating specificity of PRO20 for PRR. In cultured human neuroblastoma cells, PRO20 blocked prorenin-induced calcium influx in a concentration- and AT1 receptor–dependent manner. Intracerebroventricular infusion of PRO20 dose-dependently inhibited prorenin-induced hypertension in C57Bl6/J mice. Furthermore, acute intracerebroventricular infusion of PRO20 reduced blood pressure in both DOCA-salt and genetically hypertensive mice. Chronic intracerebroventricular infusion of PRO20 attenuated the development of hypertension and the increase in brain hypothalamic angiotensin II levels induced by DOCA-salt. In addition, chronic intracerebroventricular infusion of PRO20 improved autonomic function and spontaneous baroreflex sensitivity in mice treated with DOCA-salt. In summary, PRO20 binds to both mouse and human PRRs and decreases angiotensin II formation and hypertension induced by either prorenin or DOCA-salt. Our findings highlight the value of the novel PRR antagonist, PRO20, as a lead compound for a novel class of antihypertensive agents and as a research tool to establish the validity of brain PRR antagonism as a strategy for treating hypertension. PMID:25421983

  7. The role of endothelin-1 and endothelin receptor antagonists in allergic rhinitis inflammation: ovalbumin-induced rat model.

    Science.gov (United States)

    Tatar, A; Yayla, M; Kose, D; Halici, Z; Yoruk, O; Polat, E

    2016-09-01

    Desloratadine is a biologically active metabolite of loratadine which is indicated for the treatment of allergic rhinitis. Bosentan is a dual endothelin receptor antagonist used to treatment of pulmonary artery hypertension (PAH). In this study, we aimed to determine the role of endothelins in allergic rhinitis (AR) and the effects of endothelin receptor antagonists in AR rat models through comparison with desloratadine. In total, 20 adult Sprague-Dawley rats were used in this study. An ovalbumin-induced allergic rhinitis model was formed in three study groups except for the control group. Bosentan (100 mg/kg/day) was given to the bosentan-treated group for 7 days and desloratadine (10 mg/kg/day) was administered to the antihistaminic-treated group for 7 days. Nasal symptom scorings and histopathological examinations of the nasal tissues were carried out. Serum IgE levels and ET-1 and TNF-alpha mRNA expression levels were analysed. Between group comparisons for nasal symptoms, histopathological analysis, and molecular analyses were performed with a one-way ANOVA and Duncans multiple comparison tests. Significance was accepted at p smaller than 0.05. Bosentan inhibited nasal symptom more significantly than desloratadine. The IgE level, ET-1 and TNF-alpha mRNA expression levels statistically increased in the allergic rhinitis group when compared to other groups. Conversely, the bosentan-treatment group showed a significant recovery from the same parameters. The deterioration in histopathological parameters reached the highest levels in the allergic rhinitis group. The histopathological findings were close to those of the control group in the bosentan and antihistaminic-treated group. ET-1 is one of the mediators that impact AR development and ET-1 antagonists can be useful for symptom control and for decreasing allergic inflammation in AR patients.

  8. Cannabinoid receptor 1 antagonist treatment induces glucagon release and shows an additive therapeutic effect with GLP-1 agonist in diet-induced obese mice.

    Science.gov (United States)

    Patel, Kartikkumar Navinchandra; Joharapurkar, Amit Arvind; Patel, Vishal; Kshirsagar, Samadhan Govind; Bahekar, Rajesh; Srivastava, Brijesh Kumar; Jain, Mukul R

    2014-12-01

    Cannabinoid 1 (CB1) receptor antagonists reduce body weight and improve insulin sensitivity. Preclinical data indicates that an acute dose of CB1 antagonist rimonabant causes an increase in blood glucose. A stable analog of glucagon-like peptide 1 (GLP-1), exendin-4 improves glucose-stimulated insulin secretion in pancreas, and reduces appetite through activation of GLP-1 receptors in the central nervous system and liver. We hypothesized that the insulin secretagogue effect of GLP-1 agonist exendin-4 may synergize with the insulin-sensitizing action of rimonabant. Intraperitoneal as well as intracerebroventricular administration of rimonabant increased serum glucose upon glucose challenge in overnight fasted, diet-induced obese C57 mice, with concomitant rise in serum glucagon levels. Exendin-4 reversed the acute hyperglycemia induced by rimonabant. The combination of exendin-4 and rimonabant showed an additive effect in the food intake, and sustained body weight reduction upon repeated dosing. The acute efficacy of both the compounds was additive for inducing nausea-like symptoms in conditioned aversion test in mice, whereas exendin-4 treatment antagonized the effect of rimonabant on forced swim test upon chronic dosing. Thus, the addition of exendin-4 to rimonabant produces greater reduction in food intake owing to increased aversion, but reduces the other central nervous system side effects of rimonabant. The hyperglucagonemia induced by rimonabant is partially responsible for enhancing the antiobesity effect of exendin-4.

  9. Radiation-induced glomerular thrombus formation and nephropathy are not prevented by the ADP receptor antagonist clopidogrel

    International Nuclear Information System (INIS)

    Poele, Johannes A.M. te; Kleef, Ellen M. van; Wal, Anja F. van der; Dewit, Luc G.H.; Stewart, Fiona A.

    2001-01-01

    Purpose: To assess the effects of kidney irradiation on glomerular adenosine diphosphatase (ADPase) activity and intraglomerular microthrombus formation, and their correlation to the development of renal functional impairment. Methods and Materials: C3H/HenAf-nu + mice were given single-dose or fractionated kidney irradiations. Glomerular ADPase activity was measured using a cerium-based histochemical method. Microthrombus formation within the glomeruli was assessed by a semiquantitative immunohistochemical analysis of fibrinogen/fibrin deposits. Renal function was assessed by the [ 51 Cr]EDTA retention assay. Results: The ADPase activity was significantly reduced, to approximately 50% of pretreatment value, 4-40 weeks after 10-16 Gy single-dose irradiation and at 44 weeks after 20x2 Gy. No dose-effect relationship was found. An approximately fourfold increase in glomerular fibrinogen/fibrin staining was observed at 1 year after irradiation. This increase was not influenced by treating the mice with daily, oral clopidogrel, a platelet ADP receptor antagonist, which reduced platelet aggregation by more than 75%. Radiation-induced impairment of glomerular filtration was also not affected by the clopidogrel treatment. Conclusion: These data indicate that irradiation significantly reduced glomerular ADPase activity, which correlated with an increased glomerular fibrinogen/fibrin deposition. We were not able to reduce these prothrombotic changes, nor to protect against radiation nephropathy, by pharmacological intervention with an ADP-receptor antagonist

  10. Effect of dopamine D3 antagonists on PPI in DBA/2J mice or PPI deficit induced by neonatal ventral hippocampal lesions in rats.

    Science.gov (United States)

    Zhang, Min; Ballard, Michael E; Kohlhaas, Kathy L; Browman, Kaitlin E; Jongen-Rêlo, Ana-Lucia; Unger, Liliane V; Fox, Gerard B; Gross, Gerhard; Decker, Michael W; Drescher, Karla U; Rueter, Lynne E

    2006-07-01

    Schizophrenic patients typically exhibit impairment of sensorimotor gating, which can be modeled in animal models such as the test of prepulse inhibition of startle response (PPI) in rodents. It has been found that antipsychotics enhanced PPI in DBA mice and reversed the PPI deficit induced by neonatal ventral hippocampal (NVH) lesions in rats. However, the relative involvement of D(3) and D(2) receptors in these effects is unknown since all antipsychotics are D(2)/D(3) antagonists with limited binding preference at D(2) receptors. Therefore, in the current study, we investigated the influence of several dopamine antagonists with higher selectivity at D(3) vs D(2) receptors on PPI in DBA/2J mice and in NVH-lesioned rats. The PPI in DBA/2J mice was enhanced by the nonselective D(2)/D(3) antagonists, haloperidol at 0.3-3 mg/kg, or risperidone at 0.3-1 mg/kg, while PPI-enhancing effects were observed after the administration of higher doses of the preferential D(3)/D(2) antagonist, BP 897 at 8 mg/kg, and the selective D(3) antagonists, SB 277011 at 30 mg/kg and A-437203 at 30 mg/kg. No effect was observed following the treatment with the selective D(3) antagonist, AVE 5997 up to 30 mg/kg. The PPI deficits induced by NVH lesions were reversed by haloperidol but not by the more selective D(3) antagonists, A-437203 and AVE 5997. BP 897 enhanced PPI nonselectivity, that is, in both lesioned and nonlesioned rats. In summary, the present study indicates that PPI-enhancing effects induced by antipsychotics in DBA/2J mice and in NVH-lesioned rats are unlikely to be mediated by D(3) receptors.

  11. Characterization of subtle brain abnormalities in a mouse model of Hedgehog pathway antagonist-induced cleft lip and palate.

    Science.gov (United States)

    Lipinski, Robert J; Holloway, Hunter T; O'Leary-Moore, Shonagh K; Ament, Jacob J; Pecevich, Stephen J; Cofer, Gary P; Budin, Francois; Everson, Joshua L; Johnson, G Allan; Sulik, Kathleen K

    2014-01-01

    Subtle behavioral and cognitive deficits have been documented in patient cohorts with orofacial clefts (OFCs). Recent neuroimaging studies argue that these traits are associated with structural brain abnormalities but have been limited to adolescent and adult populations where brain plasticity during infancy and childhood may be a confounding factor. Here, we employed high resolution magnetic resonance microscopy to examine primary brain morphology in a mouse model of OFCs. Transient in utero exposure to the Hedgehog (Hh) signaling pathway antagonist cyclopamine resulted in a spectrum of facial dysmorphology, including unilateral and bilateral cleft lip and palate, cleft of the secondary palate only, and a non-cleft phenotype marked by midfacial hypoplasia. Relative to controls, cyclopamine-exposed fetuses exhibited volumetric differences in several brain regions, including hypoplasia of the pituitary gland and olfactory bulbs, hyperplasia of the forebrain septal region, and expansion of the third ventricle. However, in affected fetuses the corpus callosum was intact and normal division of the forebrain was observed. This argues that temporally-specific Hh signaling perturbation can result in typical appearing OFCs in the absence of holoprosencephaly--a condition classically associated with Hh pathway inhibition and frequently co-occurring with OFCs. Supporting the premise that some forms of OFCs co-occur with subtle brain malformations, these results provide a possible ontological basis for traits identified in clinical populations. They also argue in favor of future investigations into genetic and/or environmental modulation of the Hh pathway in the etiopathogenesis of orofacial clefting.

  12. Fasitibant chloride, a kinin B2 receptor antagonist, and dexamethasone interact to inhibit carrageenan-induced inflammatory arthritis in rats

    Science.gov (United States)

    Valenti, Claudio; Giuliani, Sandro; Cialdai, Cecilia; Tramontana, Manuela; Maggi, Carlo Alberto

    2012-01-01

    BACKGROUND AND PURPOSE Bradykinin, through the kinin B2 receptor, is involved in inflammatory processes related to arthropathies. B2 receptor antagonists inhibited carrageenan-induced arthritis in rats in synergy with anti-inflammatory steroids. The mechanism(s) underlying this drug interaction was investigated. EXPERIMENTAL APPROACH Drugs inhibiting inflammatory mediators released by carrageenan were injected, alone or in combination, into the knee joint of pentobarbital anaesthetized rats 30 min before intra-articular administration of carrageenan. Their effects on the carrageenan-induced inflammatory responses (joint pain, oedema and neutrophil recruitment) and release of inflammatory mediators (prostaglandins, IL-1β, IL-6 and the chemokine GRO/CINC-1), were assessed after 6 h. KEY RESULTS The combination of fasitibant chloride (MEN16132) and dexamethasone was more effective than each drug administered alone in inhibiting knee joint inflammation and release of inflammatory mediators. Fasitibant chloride, MK571, atenolol, des-Arg9-[Leu8]-bradykinin (B2 receptor, leukotriene, catecholamine and B1 receptor antagonists, respectively) and dexketoprofen (COX inhibitor), reduced joint pain and, except for the latter, also diminished joint oedema. A combination of drugs inhibiting joint pain (fasitibant chloride, des-Arg9-[Leu8]-bradykinin, dexketoprofen, MK571 and atenolol) and oedema (fasitibant chloride, des-Arg9-[Leu8]-bradykinin, MK571 and atenolol) abolished the respective inflammatory response, producing inhibition comparable with that achieved with the combination of fasitibant chloride and dexamethasone. MK571 alone was able to block neutrophil recruitment. CONCLUSIONS AND IMPLICATIONS Bradykinin-mediated inflammatory responses to intra-articular carrageenan were not controlled by steroids, which were not capable of preventing bradykinin effects either by direct activation of the B2 receptor, or through the indirect effects mediated by release of eicosanoids

  13. Endothelin receptor antagonist prevents parathyroid cell proliferation of low calcium diet-induced hyperparathyroidism in rats.

    Science.gov (United States)

    Kanesaka, Y; Tokunaga, H; Iwashita, K; Fujimura, S; Naomi, S; Tomita, K

    2001-01-01

    Secondary hyperparathyroidism, one of the most frequently encountered disorders of the calcium homeostasis, is characterized by an increase in parathyroid epithelial (PT) cell number, which is crucial from a functional viewpoint. However, it is still unknown what factors are involved in PT cell proliferation. Endothelin-1 (ET-1), a vasoconstrictive peptide, has been shown to act as a mitogen in a variety of cell types. Rat PT cells are reported to synthesize ET-1 and possess its receptors. To test the hypothesis that ET-1 plays a role in PT cell proliferation, we used rat test subjects fed a low calcium diet for 8 weeks (low Ca rats). The number of the proliferating PT cells, measured by proliferating cell nuclear antigen immunostaining, was significantly increased, with striking immunoreactivity of ET-1 in the low Ca rats. An endothelin receptor antagonist, bosentan (100 mg/kg.day), prevented any increase in the proliferation of PT cells in the low Ca rats (14.3 +/- 2.7/1000 PT cells with no bosentan; 2.1 +/- 1.3 with bosentan; P hyperparathyroidism.

  14. N-acetyl-L-tryptophan, a substance-P receptor antagonist attenuates aluminum-induced spatial memory deficit in rats.

    Science.gov (United States)

    Fernandes, Joylee; Mudgal, Jayesh; Rao, Chamallamudi Mallikarjuna; Arora, Devinder; Basu Mallik, Sanchari; Pai, K S R; Nampoothiri, Madhavan

    2018-06-01

    Neuroinflammation plays an important role in the pathophysiology of Alzheimer's disease. Neurokinin substance P is a key mediator which modulates neuroinflammation through neurokinin receptor. Involvement of substance P in Alzheimer's disease is still plausible and various controversies exist in this hypothesis. Preventing the deleterious effects of substance P using N-acetyl-L-tryptophan, a substance P antagonist could be a promising therapeutic strategy. This study was aimed to evaluate the effect of N-acetyl-L-tryptophan on aluminum induced spatial memory alterations in rats. Memory impairment was induced using aluminum chloride (AlCl 3 ) at a dose of 10 mg/kg for 42 d. After induction of dementia, rats were exposed to 30 and 50 mg/kg of N-acetyl-L-tryptophan for 28 d. Spatial memory alterations were measured using Morris water maze. Acetylcholinesterase activity and antioxidant enzyme glutathione level were assessed in hippocampus, frontal cortex and striatum. The higher dose of N-acetyl-L-tryptophan (50 mg/kg) significantly improved the aluminum induced memory alterations. N-acetyl-L-tryptophan exposure resulted in significant increase in acetylcholinesterase activity and glutathione level in hippocampus. The neuroprotective effect of N-acetyl-L-tryptophan could be due to its ability to block substance P mediated neuroinflammation, reduction in oxidative stress and anti-apoptotic properties. To conclude, N-acetyl-L-tryptophan may be considered as a novel neuroprotective therapy in Alzheimer's disease.

  15. LFA-1 and ICAM-1 expression induced during melanoma-endothelial cell co-culture favors the transendothelial migration of melanoma cell lines in vitro

    International Nuclear Information System (INIS)

    Ghislin, Stephanie; Obino, Dorian; Middendorp, Sandrine; Boggetto, Nicole; Alcaide-Loridan, Catherine; Deshayes, Frederique

    2012-01-01

    Patients with metastatic melanoma have a poor median rate of survival. It is therefore necessary to increase our knowledge about melanoma cell dissemination which includes extravasation, where cancer cells cross the endothelial barrier. Extravasation is well understood during travelling of white blood cells, and involves integrins such as LFA-1 (composed of two chains, CD11a and CD18) expressed by T cells, while ICAM-1 is induced during inflammation by endothelial cells. Although melanoma cell lines cross endothelial cell barriers, they do not express LFA-1. We therefore hypothesized that melanoma-endothelial cell co-culture might induce the LFA-1/ICAM ligand/receptor couple during melanoma transmigration. A transwell approach has been used as well as blocking antibodies against CD11a, CD18 and ICAM-1. Data were analyzed with an epifluorescence microscope. Fluorescence intensity was quantified with the ImageJ software. We show here that HUVEC-conditioned medium induce cell-surface expression of LFA-1 on melanoma cell lines. Similarly melanoma-conditioned medium activates ICAM-1 expression in endothelial cells. Accordingly blocking antibodies of ICAM-1, CD11a or CD18 strongly decrease melanoma transmigration. We therefore demonstrate that melanoma cells can cross endothelial monolayers in vitro due to the induction of ICAM-1 and LFA-1 occurring during the co-culture of melanoma and endothelial cells. Our data further suggest a role of LFA-1 and ICAM-1 in the formation of melanoma cell clumps enhancing tumor cell transmigration. Melanoma-endothelial cell co-culture induces LFA-1 and ICAM-1 expression, thereby favoring in vitro melanoma trans-migration

  16. LFA-1 and ICAM-1 expression induced during melanoma-endothelial cell co-culture favors the transendothelial migration of melanoma cell lines in vitro

    Directory of Open Access Journals (Sweden)

    Ghislin Stephanie

    2012-10-01

    Full Text Available Abstract Background Patients with metastatic melanoma have a poor median rate of survival. It is therefore necessary to increase our knowledge about melanoma cell dissemination which includes extravasation, where cancer cells cross the endothelial barrier. Extravasation is well understood during travelling of white blood cells, and involves integrins such as LFA-1 (composed of two chains, CD11a and CD18 expressed by T cells, while ICAM-1 is induced during inflammation by endothelial cells. Although melanoma cell lines cross endothelial cell barriers, they do not express LFA-1. We therefore hypothesized that melanoma-endothelial cell co-culture might induce the LFA-1/ICAM ligand/receptor couple during melanoma transmigration. Methods A transwell approach has been used as well as blocking antibodies against CD11a, CD18 and ICAM-1. Data were analyzed with an epifluorescence microscope. Fluorescence intensity was quantified with the ImageJ software. Results We show here that HUVEC-conditioned medium induce cell-surface expression of LFA-1 on melanoma cell lines. Similarly melanoma-conditioned medium activates ICAM-1 expression in endothelial cells. Accordingly blocking antibodies of ICAM-1, CD11a or CD18 strongly decrease melanoma transmigration. We therefore demonstrate that melanoma cells can cross endothelial monolayers in vitro due to the induction of ICAM-1 and LFA-1 occurring during the co-culture of melanoma and endothelial cells. Our data further suggest a role of LFA-1 and ICAM-1 in the formation of melanoma cell clumps enhancing tumor cell transmigration. Conclusion Melanoma-endothelial cell co-culture induces LFA-1 and ICAM-1 expression, thereby favoring in vitro melanoma trans-migration.

  17. Effect of the AT1-receptor antagonists losartan, irbesartan, and telmisartan on angiotensin II-induced facilitation of sympathetic neurotransmission in the rat mesenteric artery

    NARCIS (Netherlands)

    Balt, J. C.; Mathy, M. J.; Nap, A.; Pfaffendorf, M.; van Zwieten, P. A.

    2001-01-01

    SUMMARY: The effect of the AT1-receptor antagonists losartan, irbesartan, and telmisartan on angiotensin II (Ang II)-induced facilitation of noradrenergic neurotransmission was investigated in the isolated rat mesenteric artery under isometric conditions. Electrical field stimulation (2, 4, and 8

  18. Neuroprotection Against NMDA Induced Cell Death in Rat Nucleus Basalis by Ca2+ Antagonist Nimodipine, Influence of Aging and Developmental Drug Treatment

    NARCIS (Netherlands)

    Luiten, P.G.M.; Douma, B.R.K.; Zee, E.A. van der; Nyakas, C.

    In the current study the neuroprotective effect of the L-type calcium channel antagonist nimodipine in rat brain was investigated in N-methyl-D-aspartate-induced neuronal degeneration in vivo. In the present model NMDA was unilaterally injected in the magnocellular nucleus basalis and the neurotoxic

  19. Vitamin K-antagonists accelerate atherosclerotic calcification and induce a vulnerable plaque phenotype.

    Directory of Open Access Journals (Sweden)

    Leon J Schurgers

    Full Text Available Vitamin K-antagonists (VKA are treatment of choice and standard care for patients with venous thrombosis and thromboembolic risk. In experimental animal models as well as humans, VKA have been shown to promote medial elastocalcinosis. As vascular calcification is considered an independent risk factor for plaque instability, we here investigated the effect of VKA on coronary calcification in patients and on calcification of atherosclerotic plaques in the ApoE(-/- model of atherosclerosis.A total of 266 patients (133 VKA users and 133 gender and Framingham Risk Score matched non-VKA users underwent 64-slice MDCT to assess the degree of coronary artery disease (CAD. VKA-users developed significantly more calcified coronary plaques as compared to non-VKA users. ApoE(-/- mice (10 weeks received a Western type diet (WTD for 12 weeks, after which mice were fed a WTD supplemented with vitamin K(1 (VK(1, 1.5 mg/g or vitamin K(1 and warfarin (VK(1&W; 1.5 mg/g & 3.0 mg/g for 1 or 4 weeks, after which mice were sacrificed. Warfarin significantly increased frequency and extent of vascular calcification. Also, plaque calcification comprised microcalcification of the intimal layer. Furthermore, warfarin treatment decreased plaque expression of calcification regulatory protein carboxylated matrix Gla-protein, increased apoptosis and, surprisingly outward plaque remodeling, without affecting overall plaque burden.VKA use is associated with coronary artery plaque calcification in patients with suspected CAD and causes changes in plaque morphology with features of plaque vulnerability in ApoE(-/- mice. Our findings underscore the need for alternative anticoagulants that do not interfere with the vitamin K cycle.

  20. Quinidine, but not eicosanoid antagonists or dexamethasone, protect the gut from platelet activating factor-induced vasoconstriction, edema and paralysis.

    Science.gov (United States)

    Lautenschläger, Ingmar; Frerichs, Inéz; Dombrowsky, Heike; Sarau, Jürgen; Goldmann, Torsten; Zitta, Karina; Albrecht, Martin; Weiler, Norbert; Uhlig, Stefan

    2015-01-01

    Intestinal circulatory disturbances, atony, edema and swelling are of great clinical relevance, but the related mechanisms and possible therapeutic options are poorly characterized, in part because of the difficulties to comprehensively analyze these conditions. To overcome these limitations we have developed a model of the isolated perfused rat small intestine where all of these symptoms can be studied simultaneously. Here we used this model to study the role of eicosanoids, steroids and quinidine in platelet-activating factor (PAF)-induced intestinal disorders. A vascular bolus of PAF (0.5 nmol) triggered release of thromboxane and peptidoleukotrienes into the vascular bed (peak concentration 35 nM and 0.8 nM) and reproduced all symptoms of intestinal failure: mesenteric vasoconstriction, translocation of fluid and macromolecules from the vasculature to the lumen and lymphatics, intestinal edema formation, loss of intestinal peristalsis and decreased galactose uptake. All effects of PAF were abolished by the PAF-receptor antagonist ABT491 (2.5 μM). The COX and LOX inhibitors ASA and AA861 (500 μM, 10 μM) did not exhibit barrier-protective effects and the eicosanoid antagonists SQ29548 and MK571 (10 μM, each) only moderately attenuated the loss of vascular fluid, the redistribution to the lumen and the transfer of FITC dextran to the lumen. The steroid dexamethasone (10 μM) showed no barrier-protective properties and failed to prevent edema formation. Quinidine (100 μM) inhibited the increase in arterial pressure, stabilized all the intestinal barriers, and reduced lymph production and the transfer of FITC dextran to the lymph. While quinidine by itself reduced peristalsis, it also obviated paralysis, preserved intestinal functions and prevented edema formation. We conclude that quinidine exerts multiple protective effects against vasoconstriction, edema formation and paralysis in the intestine. The therapeutic use of quinidine for intestinal ailments

  1. Impact of a CXCL12/CXCR4 Antagonist in Bleomycin (BLM Induced Pulmonary Fibrosis and Carbon Tetrachloride (CCl4 Induced Hepatic Fibrosis in Mice.

    Directory of Open Access Journals (Sweden)

    Leola N Chow

    Full Text Available Modulation of chemokine CXCL12 and its receptor CXCR4 has been implicated in attenuation of bleomycin (BLM-induced pulmonary fibrosis and carbon tetrachloride (CCl4-induced hepatic injury. In pulmonary fibrosis, published reports suggest that collagen production in the injured lung is derived from fibrocytes recruited from the circulation in response to release of pulmonary CXCL12. Conversely, in hepatic fibrosis, resident hepatic stellate cells (HSC, the key cell type in progression of fibrosis, upregulate CXCR4 expression in response to activation. Further, CXCL12 induces HSC proliferation and subsequent production of collagen I. In the current study, we evaluated AMD070, an orally bioavailable inhibitor of CXCL12/CXCR4 in alleviating BLM-induced pulmonary and CCl4-induced hepatic fibrosis in mice. Similar to other CXCR4 antagonists, treatment with AMD070 significantly increased leukocyte mobilization. However, in these two models of fibrosis, AMD070 had a negligible impact on extracellular matrix deposition. Interestingly, our results indicated that CXCL12/CXCR4 signaling has a role in improving mortality associated with BLM induced pulmonary injury, likely through dampening an early inflammatory response and/or vascular leakage. Together, these findings indicate that the CXCL12-CXCR4 signaling axis is not an effective target for reducing fibrosis.

  2. Antagonist Effects of Veratric Acid against UVB-Induced Cell Damages

    Directory of Open Access Journals (Sweden)

    Deokhoon Park

    2013-05-01

    Full Text Available Ultraviolet (UV radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, 3,4-dimethoxybenzoic acid is one of the major benzoic acid derivatives from vegetables and fruits and it also occurs naturally in medicinal mushrooms which have been reported to have anti-inflammatory and anti-oxidant activities. However, it has rarely been applied in skin care. This study, therefore, aimed to explore the possible roles of veratric acid in protection against UVB-induced damage in HaCaT cells. Results showed that veratric acid can attenuate cyclobutane pyrimidine dimers (CPDs formation, glutathione (GSH depletion and apoptosis induced by UVB. Furthermore, veratric acid had inhibitory effects on the UVB-induced release of the inflammatory mediators such as IL-6 and prostaglandin-E2. We also confirmed the safety and clinical efficacy of veratric acid on human skin. Overall, results demonstrated significant benefits of veratric acid on the protection of keratinocyte against UVB-induced injuries and suggested its potential use in skin photoprotection.

  3. Antagonist effects of veratric acid against UVB-induced cell damages.

    Science.gov (United States)

    Shin, Seoung Woo; Jung, Eunsun; Kim, Seungbeom; Lee, Kyung-Eun; Youm, Jong-Kyung; Park, Deokhoon

    2013-05-10

    Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, 3,4-dimethoxybenzoic acid) is one of the major benzoic acid derivatives from vegetables and fruits and it also occurs naturally in medicinal mushrooms which have been reported to have anti-inflammatory and anti-oxidant activities. However, it has rarely been applied in skin care. This study, therefore, aimed to explore the possible roles of veratric acid in protection against UVB-induced damage in HaCaT cells. Results showed that veratric acid can attenuate cyclobutane pyrimidine dimers (CPDs) formation, glutathione (GSH) depletion and apoptosis induced by UVB. Furthermore, veratric acid had inhibitory effects on the UVB-induced release of the inflammatory mediators such as IL-6 and prostaglandin-E2. We also confirmed the safety and clinical efficacy of veratric acid on human skin. Overall, results demonstrated significant benefits of veratric acid on the protection of keratinocyte against UVB-induced injuries and suggested its potential use in skin photoprotection.

  4. 5-Methoxy-N,N-dimethyltryptamine-induced analgesia is blocked by alpha-adrenoceptor antagonists in rats.

    Science.gov (United States)

    Archer, T.; Danysz, W.; Jonsson, G.; Minor, B. G.; Post, C.

    1986-01-01

    The effects of the alpha-adrenoceptor antagonists prazosin, phentolamine and yohimbine upon 5-methoxy-N,N-dimethyltryptamine (5-MeODMT)-induced analgesia were tested in the hot-plate, tail-flick and shock-titration tests of nociception with rats. Intrathecally injected yohimbine and phentolamine blocked or attenuated the analgesia produced by systemic administration of 5-MeODMT in all three nociceptive tests. Intrathecally administered prazosin attenuated the analgesic effects of 5-MeODMT in the hot-plate and tail-flick tests, but not in the shock titration test. Intrathecal yohimbine showed a dose-related lowering of pain thresholds in saline and 5-MeODMT-treated animals. Phentolamine and prazosin produced normal dose-related curves in the hot-plate test and biphasic effects in the shock titration and tail-flick tests. These results demonstrate a functional interaction between alpha 2-adrenoceptors and 5-HT agonist-induced analgesia at a spinal level in rats. PMID:2877697

  5. The selective orexin receptor 1 antagonist ACT-335827 in a rat model of diet-induced obesity associated with metabolic syndrome

    OpenAIRE

    Steiner, Michel A.; Sciarretta, Carla; Pasquali, Anne; Jenck, Francois

    2013-01-01

    The orexin system regulates feeding, nutrient metabolism and energy homeostasis. Acute pharmacological blockade of orexin receptor 1 (OXR-1) in rodents induces satiety and reduces normal and palatable food intake. Genetic OXR-1 deletion in mice improves hyperglycemia under high-fat (HF) diet conditions. Here we investigated the effects of chronic treatment with the novel selective OXR-1 antagonist ACT-335827 in a rat model of diet-induced obesity (DIO) associated with metabolic syndrome (MetS...

  6. Effects of the histamine H₃ receptor antagonist ABT-239 on cognition and nicotine-induced memory enhancement in mice.

    Science.gov (United States)

    Kruk, Marta; Miszkiel, Joanna; McCreary, Andrew C; Przegaliński, Edmund; Filip, Małgorzata; Biała, Grażyna

    2012-01-01

    The strong correlation between central histaminergic and cholinergic pathways on cognitive processes has been reported extensively. However, the role of histamine H(3) receptor mechanisms interacting with nicotinic mechanisms has not previously been extensively investigated. The current study was conducted to determine the interactions of nicotinic and histamine H(3) receptor systems with regard to learning and memory function using a modified elevated plus-maze test in mice. In this test, the latency for mice to move from the open arm to the enclosed arm (i.e., transfer latency) was used as an index of memory. We tested whether ABT-239 (4-(2-{2-[(2R)-2-methylpyrrolidinyl]ethyl}-benzofuran-5-yl), an H(3) receptor antagonist/inverse agonist, had influence on two different stages of memory, i.e., memory acquisition and consolidation (administered prior to or immediately after the first trial, respectively) and whether ABT-239 influenced nicotine-induced memory enhancement. Our results revealed that the acute administration of nicotine (0.035 and 0.175 mg/kg), but not of ABT-239 (0.1-3 mg/kg) reduced transfer latency in the acquisition and consolidation phases. In combination studies, concomitant administration of either ABT-239 (1 and 3 mg/kg) and nicotine (0.035 mg/kg), or ABT-239 (0.1 mg/kg) and nicotine (0.0175 mg/kg) further increased nicotine-induced improvement in both memory acquisition and consolidation. The present data confirm an important role for H(3) receptors in regulating nicotine-induced mnemonic effects since inhibition of H(3) receptors augmented nicotine-induced memory enhancement in mice.

  7. Inhibition of Common Cold-Induced Aggravation of Childhood Asthma by Leukotriene Receptor Antagonists

    Directory of Open Access Journals (Sweden)

    Shigemi Yoshihara

    2012-01-01

    Conclusions: : These findings showed a high prevalence of common cold in younger patients with childhood asthma and indicated that common cold can induce aggravation of asthma. LTRAs are useful for long-term asthma control in very young patients who develop an asthma attack due to a common cold.

  8. Role of Leukotriene Receptor Antagonists in the Treatment of Exercise-Induced Bronchoconstriction: A Review

    Directory of Open Access Journals (Sweden)

    Philteos George S

    2005-06-01

    Full Text Available Abstract Asthma is a very common disorder that still causes significant morbidity and mortality. A high percentage of individuals with asthma also experience exercise-induced bronchoconstriction (EIB. This article reviews the current literature and updates the reader on the safety, efficacy, and clinical applications of leukotriene modifiers in the treatment of EIB.

  9. Antagonist Effects of Veratric Acid against UVB-Induced Cell Damages

    OpenAIRE

    Shin, Seoung; Jung, Eunsun; Kim, Seungbeom; Lee, Kyung-Eun; Youm, Jong-Kyung; Park, Deokhoon

    2013-01-01

    Ultraviolet (UV) radiation induces DNA damage, oxidative stress, and inflammatory processes in human epidermis, resulting in inflammation, photoaging, and photocarcinogenesis. Adequate protection of skin against the harmful effect of UV irradiation is essential. In recent years naturally occurring herbal compounds such as phenolic acids, flavonoids, and high molecular weight polyphenols have gained considerable attention as beneficial protective agents. The simple phenolic veratric acid (VA, ...

  10. Inhibition of Common Cold-Induced Aggravation of Childhood Asthma by Leukotriene Receptor Antagonists

    OpenAIRE

    Shigemi Yoshihara; Hironobu Fukuda; Toshio Abe; Mitsuhiro Nishida; Yumi Yamada; Noriko Kanno; Osamu Arisaka

    2012-01-01

    Background: : Virus infection is an important risk factor for aggravation of childhood asthma. The objective of this study was to examine the effect of drugs on aggravation of asthma induced by a common cold. Methods: : Asthma control was examined in a survey of 1,014 Japanese pediatric patients with bronchial asthma. The occurrence of common cold, asthma control, and drugs used for asthma control were investigated using a modified Childhood Asthma Control Test (C-ACT) for patients aged

  11. Exon level transcriptomic profiling of HIV-1-infected CD4(+ T cells reveals virus-induced genes and host environment favorable for viral replication.

    Directory of Open Access Journals (Sweden)

    Michaël Imbeault

    Full Text Available HIV-1 is extremely specialized since, even amongst CD4(+ T lymphocytes (its major natural reservoir in peripheral blood, the virus productively infects only a small proportion of cells under an activated state. As the percentage of HIV-1-infected cells is very low, most studies have so far failed to capture the precise transcriptomic profile at the whole-genome scale of cells highly susceptible to virus infection. Using Affymetrix Exon array technology and a reporter virus allowing the magnetic isolation of HIV-1-infected cells, we describe the host cell factors most favorable for virus establishment and replication along with an overview of virus-induced changes in host gene expression occurring exclusively in target cells productively infected with HIV-1. We also establish that within a population of activated CD4(+ T cells, HIV-1 has no detectable effect on the transcriptome of uninfected bystander cells at early time points following infection. The data gathered in this study provides unique insights into the biology of HIV-1-infected CD4(+ T cells and identifies genes thought to play a determinant role in the interplay between the virus and its host. Furthermore, it provides the first catalogue of alternative splicing events found in primary human CD4(+ T cells productively infected with HIV-1.

  12. KPR-2579, a novel TRPM8 antagonist, inhibits acetic acid-induced bladder afferent hyperactivity in rats.

    Science.gov (United States)

    Aizawa, Naoki; Fujimori, Yoshikazu; Kobayashi, Jun-Ichi; Nakanishi, Osamu; Hirasawa, Hideaki; Kume, Haruki; Homma, Yukio; Igawa, Yasuhiko

    2018-02-21

    Transient receptor potential melastatin 8 (TRPM8) is proposed to be a promising therapeutic target for hypersensitive bladder disorders. We examined the effects of KPR-2579, a novel selective TRPM8 antagonist, on body temperature and on mechanosensitive bladder single-unit afferent activities (SAAs) provoked by intravesical acetic acid (AA) instillation in rats. Female Sprague-Dawley rats were used. Effects of cumulative intravenous (i.v.) administrations of KPR-2579 (0.03-1 mg/kg) on deep body temperature were investigated (N = 18). In separate animals, effects of bolus administration of KPR-2579 (0.03 or 0.3 mg/kg, i.v.) on bladder hyperactivity induced by intravesical instillation of 0.1% AA were investigated using cystometry (N = 57) in a conscious free-moving condition or urethane-anesthetized condition, and SAA measurements (N = 41) were performed in a urethane-anesthetized condition. KPR-2579 at any doses tested did not affect body temperature. In cystometry measurements, a high dose (0.3 mg/kg) of KPR-2579 counteracted the shortened intercontraction interval provoked by AA instillation. In SAA measurements, 48 single afferent fibers (n = 24 in each fiber) were isolated. AA instillations significantly increased the SAAs of C fibers, but not of Aδ fibers, in the presence of KPR-2579's vehicle and a low dose (0.03 mg/kg) of KPR-2579. Pretreatment with a high dose (0.3 mg/kg) of KPR-2579 significantly inhibited the AA-induced activation of C-fiber SAAs. The present results suggest that TRPM8 channels play a role in the AA-induced pathological activation of mechanosensitive bladder C fibers in rats. KRP-2579 may be a promising drug for hypersensitive bladder disorders. © 2018 Wiley Periodicals, Inc.

  13. Stress-induced visceral hypersensitivity in maternally separated rats can be reversed by peripherally restricted histamine-1-receptor antagonists

    NARCIS (Netherlands)

    Stanisor, Oana I.; van Diest, Sophie A.; Yu, Zhumei; Welting, Olaf; Bekkali, Noor; Shi, Jing; de Jonge, Wouter J.; Boeckxstaens, Guy E.; van den Wijngaard, Rene M.

    2013-01-01

    The histamine-1 receptor (H1R) antagonist ketotifen increased the threshold of discomfort in hypersensitive IBS patients. The use of peripherally restricted and more selective H1R antagonists may further improve treatment possibilities. We examined the use of fexofenadine and ebastine to reverse

  14. The IL-6 receptor super-antagonist Sant7 enhances antiproliferative and apoptotic effects induced by dexamethasone and zoledronic acid on multiple myeloma cells.

    Science.gov (United States)

    Tassone, Pierfrancesco; Galea, Eulalia; Forciniti, Samantha; Tagliaferri, Pierosandro; Venuta, Salvatore

    2002-10-01

    Interleukin-6 (IL-6) is the major growth and survival factor for multiple myeloma (MM), and has been shown to protect MM cells from apoptosis induced by a variety of agents. IL-6 receptor antagonists, which prevent the assembly of functional IL-6 receptor complexes, inhibit cell proliferation and induce apoptosis in MM cells. We have investigated whether the IL-6 receptor super-antagonist Sant7 might enhance the antiproliferative and apoptotic effects induced by the combination of dexamethasone (Dex) and zoledronic acid (Zln) on human MM cell lines and primary cells from MM patients. Here we show that each of these compounds individually induced detectable antiproliferative effects on MM cells. Sant7 significantly enhanced growth inhibition and apoptosis induced by Dex and Zln on both MM cell lines and primary MM cells. These results indicate that overcoming IL-6 mediated cell resistance by Sant7 potentiates the effect of glucocorticoides and bisphosphonates on MM cell growth and survival, providing a rationale for therapies including IL-6 antagonists in MM.

  15. A RNA antagonist of hypoxia-inducible factor-1alpha, EZN-2968, inhibits tumor cell growth

    DEFF Research Database (Denmark)

    Greenberger, Lee M; Horak, Ivan D; Filpula, David

    2008-01-01

    Hypoxia-inducible factor-1 (HIF-1) is a transcription factor that plays a critical role in angiogenesis, survival, metastasis, drug resistance, and glucose metabolism. Elevated expression of the alpha-subunit of HIF-1 (HIF-1alpha), which occurs in response to hypoxia or activation of growth factor...... the expression of HIF-1alpha mRNA. In vitro, in human prostate (15PC3, PC3, and DU145) and glioblastoma (U373) cells, EZN-2968 induced a potent, selective, and durable antagonism of HIF-1 mRNA and protein expression (IC(50), 1-5 nmol/L) under normoxic and hypoxic conditions associated with inhibition of tumor......-regulation of endogenous HIF-1alpha and vascular endothelial growth factor in the liver. The effect can last for days after administration of single dose of EZN-2968 and is associated with long residence time of locked nucleic acid in certain tissues. In efficacy studies, tumor reduction was found in nude mice implanted...

  16. Reversal of TMS-induced motor twitch by training is associated with a reduction in excitability of the antagonist muscle

    Directory of Open Access Journals (Sweden)

    Fregni Felipe

    2011-08-01

    Full Text Available Abstract Background A single session of isolated repetitive movements of the thumb can alter the response to transcranial magnetic stimulation (TMS, such that the related muscle twitch measured post-training occurs in the trained direction. This response is attributed to transient excitability changes in primary motor cortex (M1 that form the early part of learning. We investigated; (1 whether this phenomenon might occur for movements at the wrist, and (2 how specific TMS activation patterns of opposing muscles underlie the practice-induced change in direction. Methods We used single-pulse suprathreshold TMS over the M1 forearm area, to evoke wrist movements in 20 healthy subjects. We measured the preferential direction of the TMS-induced twitch in both the sagittal and coronal plane using an optical goniometer fixed to the dorsum of the wrist, and recorded electromyographic (EMG activity from the flexor carpi radialis (FCR and extensor carpi radialis (ECR muscles. Subjects performed gentle voluntary movements, in the direction opposite to the initial twitch for 5 minutes at 0.2 Hz. We collected motor evoked potentials (MEPs elicited by TMS at baseline and for 10 minutes after training. Results Repetitive motor training was sufficient for TMS to evoke movements in the practiced direction opposite to the original twitch. For most subjects the effect of the newly-acquired direction was retained for at least 10 minutes before reverting to the original. Importantly, the direction change of the movement was associated with a significant decrease in MEP amplitude of the antagonist to the trained muscle, rather than an increase in MEP amplitude of the trained muscle. Conclusions These results demonstrate for the first time that a TMS-twitch direction change following a simple practice paradigm may result from reduced corticospinal drive to muscles antagonizing the trained direction. Such findings may have implications for training paradigms in

  17. Non-analgesic effects of opioids: management of opioid-induced constipation by peripheral opioid receptor antagonists: prevention or withdrawal?

    Science.gov (United States)

    Holzer, Peter

    2012-01-01

    The therapeutic action of opioid analgesics is compromised by peripheral adverse effects among which opioid-induced constipation (OIC) is the most disabling, with a prevalence reported to vary between 15 and 90 %. Although OIC is usually treated with laxatives, there is insufficient clinical evidence that laxatives are efficacious in this indication. In contrast, there is ample evidence from double- blind, randomized and placebo-controlled trials that peripheral opioid receptor antagonists (PORAs) counteract OIC. This specific treatment modality is currently based on subcutaneous methylnaltrexone for the interruption of OIC in patients with advanced illness, and a fixed combination of oral prolonged-release naloxone with prolonged-release oxycodone for the prevention of OIC in the treatment of non-cancer and cancer pain. Both drugs counteract OIC while the analgesic effect of opioids remains unabated. The clinical studies show that more than 50 % of the patients with constipation under opioid therapy may benefit from the use of PORAs, while PORA-resistant patients are likely to suffer from non-opioid-induced constipation, the prevalence of which increases with age. While the addition of naloxone to oxycodone seems to act by preventing OIC, the intermittent dosing of methylnaltrexone every other day seems to stimulate defaecation by provoking an intestinal withdrawal response. The availability of PORAs provides a novel opportunity to specifically control OIC and other peripheral adverse effects of opioid analgesics (e.g., urinary retention and pruritus). The continuous dosing of a PORA has the advantage of few adverse effects, while intermittent dosing of a PORA can be associated with abdominal cramp-like pain.

  18. Stereoselective inhibition of thromboxane-induced coronary vasoconstriction by 1,4-dihydropyridine calcium channel antagonists

    International Nuclear Information System (INIS)

    Eltze, M.; Boer, R.; Sanders, K.H.; Boss, H.; Ulrich, W.R.; Flockerzi, D.

    1990-01-01

    The biological activity of the (+)-S- and (-)-R-enantiomers of niguldipine, of the (-)-S- and (+)-R-enantiomers of felodipine and nitrendipine, and of rac-nisoldipine and rac-nimodipine was investigated in vitro and in vivo. Inhibition of coronary vasoconstriction due to the thromboxane A2 (TxA2)-mimetic U-46619 in guinea pig Langendorff hearts, displacement of (+)-[ 3 H]isradipine from calcium channel binding sites of guinea pig skeletal muscle T-tubule membranes, and blood pressure reduction in spontaneously hypertensive rats were determined. The enantiomers were obtained by stereoselective synthesis. Cross-contamination was less than 0.5% for both S- and R-enantiomers of niguldipine and nitrendipine and less than 1% for those of felodipine. From the doses necessary for a 50% inhibition of coronary vasoconstriction, stereoselectivity ratios for (+)-(S)-/(-)-(R)-niguldipine, (-)-(S)-/(+)-(R)-felodipine, and (-)-(S)-/(+)-(R)-nitrendipine of 28, 13, and 7, respectively, were calculated. The potency ratio rac-nisoldipine/rac-nimodipine was 3.5. Ratios obtained from binding experiments and antihypertensive activity were (+)-(S)-/(-)-(R)-niguldipine = 45 and 35, (-)-(S)-/(+)-(R)-felodipine = 12 and 13, (-)-(S)-/(+)-(R)-nitrendipine = 8 and 8, and rac-nisoldipine/rac-nimodipine = 8 and 7, respectively. Highly significant correlations were found between the in vitro potency of the substances to prevent U-46619-induced coronary vasoconstriction and their affinity for calcium channel binding sites as well as their antihypertensive activity

  19. Peritoneal milky spots serve as a hypoxic niche and favor gastric cancer stem/progenitor cell peritoneal dissemination through hypoxia-inducible factor 1α.

    Science.gov (United States)

    Miao, Zhi-Feng; Wang, Zhen-Ning; Zhao, Ting-Ting; Xu, Ying-Ying; Gao, Jian; Miao, Feng; Xu, Hui-Mian

    2014-12-01

    Peritoneal dissemination is the most common cause of death in gastric cancer patients. The hypoxic microenvironment plays a major role in controlling the tumor stem cell phenotype and is associated with patients' prognosis through hypoxia-inducible factor-1α (HIF-1α), a key transcriptional factor that responds to hypoxic stimuli. During the peritoneal dissemination process, gastric cancer stem/progenitor cells (GCSPCs) are thought to enter into and maintained in peritoneal milky spots (PMSs), which have hypoxic microenvironments. However, the mechanism through which the hypoxic environment of PMSs regulated GCSPC maintenance is still poorly understood. Here, we investigated whether hypoxic PMSs were an ideal cancer stem cell niche suitable for GCSPC engraftment. We also evaluated the mechanisms through which the HIF-1α-mediated hypoxic microenvironment regulated GCSPC fate. We observed a positive correlation between HIF-1α expression and gastric cancer peritoneal dissemination (GCPD) in gastric cancer patients. Furthermore, the GCSPC population expanded in primary gastric cancer cells under hypoxic condition in vitro, and hypoxic GCSPCs showed enhanced self-renewal ability, but reduced differentiation capacity, mediated by HIF-1α. In an animal model, GCSPCs preferentially resided in the hypoxic zone of PMSs; moreover, when the hypoxic microenvironment in PMSs was destroyed, GCPD was significantly alleviated. In conclusion, our results demonstrated that PMSs served as a hypoxic niche and favored GCSPCs peritoneal dissemination through HIF-1α both in vitro and in vivo. These results provided new insights into the GCPD process and may lead to advancements in the clinical treatment of gastric cancer. © 2014 The Authors. STEM CELLS Published by Wiley Periodicals, Inc. on behalf of AlphaMed Press.

  20. NMDA receptor activation antagonizes the NMDA antagonist-induced antianxiety effect in the elevated plus-maze test in mice.

    Science.gov (United States)

    Poleszak, Ewa; Serefko, Anna; Szopa, Aleksandra; Wośko, Sylwia; Dudka, Jarosław; Wróbel, Andrzej; Oniszczuk, Tomasz; Wlaź, Piotr

    2013-01-01

    The purpose of this study was to determine how the activation of different regulatory domains of the NMDA complex affects the antianxiety effect of antagonists acting at its distinct binding sites. The anxiolytic-like activity was assessed by the elevated plus-maze test in mice. The anxiolytic activity of CGP 37849 (a competitive NMDA receptor antagonist) and L-701,324 (an antagonist at glycine site) was confirmed, but effects of both were significantly reduced by N-methyl-D-aspartic acid (NMDA) or by D-serine agonists at glutamate and glycine site of the NMDA receptor complex, respectively. The obtained data suggest that stimulation of the glutamate or glycine recognition site of the NMDA receptor complex significantly decreases the antianxiety properties of antagonists of either site.

  1. Closed headpiece of integrin [alpah]IIb[beta]3 and its complex with an [alpha]IIb[beta]3-specific antagonist that does not induce opening

    Energy Technology Data Exchange (ETDEWEB)

    Zhu, Jieqing; Zhu, Jianghai; Negri, Ana; Provasi, Davide; Filizola, Marta; Coller, Barry S.; Springer, Timothy A. (Sinai); (Rockefeller); (CH-Boston)

    2011-08-24

    The platelet integrin {alpha}{sub IIb}{beta}{sub 3} is essential for hemostasis and thrombosis through its binding of adhesive plasma proteins. We have determined crystal structures of the {alpha}{sub IIb}{beta}{sub 3} headpiece in the absence of ligand and after soaking in RUC-1, a novel small molecule antagonist. In the absence of ligand, the {alpha}{sub IIb}{beta}{sub 3} headpiece is in a closed conformation, distinct from the open conformation visualized in presence of Arg-Gly-Asp (RGD) antagonists. In contrast to RGD antagonists, RUC-1 binds only to the {alpha}{sub IIb} subunit. Molecular dynamics revealed nearly identical binding. Two species-specific residues, {alpha}{sub IIb} Y190 and {alpha}{sub aIIb} D232, in the RUC-1 binding site were confirmed as important by mutagenesis. In sharp contrast to RGD-based antagonists, RUC-1 did not induce {alpha}{sub IIb}{beta}{sub 3} to adopt an open conformation, as determined by gel filtration and dynamic light scattering. These studies provide insights into the factors that regulate integrin headpiece opening, and demonstrate the molecular basis for a novel mechanism of integrin antagonism.

  2. Chronic escitalopram treatment caused dissociative adaptation in serotonin (5-HT) 2C receptor antagonist-induced effects in REM sleep, wake and theta wave activity.

    Science.gov (United States)

    Kostyalik, Diána; Kátai, Zita; Vas, Szilvia; Pap, Dorottya; Petschner, Péter; Molnár, Eszter; Gyertyán, István; Kalmár, Lajos; Tóthfalusi, László; Bagdy, Gyorgy

    2014-03-01

    Several multi-target drugs used in treating psychiatric disorders, such as antidepressants (e.g. agomelatine, trazodone, nefazodone, amitriptyline, mirtazapine, mianserin, fluoxetine) or most atypical antipsychotics, have 5-hydroxytryptamine 2C (5-HT2C) receptor-blocking property. Adaptive changes in 5-HT2C receptor-mediated functions are suggested to contribute to therapeutic effects of selective serotonin reuptake inhibitor (SSRI) antidepressants after weeks of treatment, at least in part. Beyond the mediation of anxiety and other functions, 5-HT2C receptors are involved in sleep regulation. Anxiety-related adaptive changes caused by antidepressants have been studied extensively, although sleep- and electroencephalography (EEG)-related functional studies are still lacking. The aim of this study was to investigate the effects of chronic SSRI treatment on 5-HT2C receptor antagonist-induced functions in different vigilance stages and on quantitative EEG (Q-EEG) spectra. Rats were treated with a single dose of the selective 5-HT2C receptor antagonist SB-242084 (1 mg/kg, i.p.) or vehicle at the beginning of passive phase following a 20-day-long SSRI (escitalopram; 10 mg/kg/day, osmotic minipump) or VEHICLE pretreatment. Fronto-parietal electroencephalogram, electromyogram and motility were recorded during the first 3 h of passive phase. We found that the chronic escitalopram pretreatment attenuated the SB-242084-caused suppression in rapid eye movement sleep (REMS). On the contrary, the 5-HT2C receptor antagonist-induced elevations in passive wake and theta (5-9 Hz) power density during active wake and REMS were not affected by the SSRI. In conclusion, attenuation in certain, but not all vigilance- and Q-EEG-related functions induced by the 5-HT2C receptor antagonist, suggests dissociation in 5-HT2C receptor adaptation.

  3. A randomised trial evaluating the effects of the TRPV1 antagonist SB705498 on pruritus induced by histamine, and cowhage challenge in healthy volunteers.

    Directory of Open Access Journals (Sweden)

    Rachel A Gibson

    Full Text Available Transient receptor potential vanilloid type 1 (TRPV1 is a non-selective cation channel widely expressed in skin tissues, and peripheral sensory nerve fibres. Activation of TRPV1 releases neuropeptides; the resulting neurogenic inflammation is believed to contribute to the development of pruritus. A TRPV1 antagonist has the potential to perform as an anti-pruritic agent. SB705498 is a TRPV1 antagonist that has demonstrated in vitro activity against cloned TRPV1 human receptors and when orally administered has demonstrated pharmacodynamic activity in animal models and clinical studies.To select a topical dose of SB705498 using the TRPV1 agonist capsaicin; to confirm engagement of the TRPV1 antagonistic action of SB705498 and assess whether the dose selected has an effect on itch induced by two challenge agents.A clinical study was conducted in 16 healthy volunteers to assess the effects of 3 doses of SB705498 on skin flare induced by capsaicin. Subjects with a robust capsaicin response were chosen to determine if the selected topical formulation of SB705498 had an effect on challenge agent induced itch.Following capsaicin challenge the greatest average reduction in area of flare was seen for the 3% formulation. This dose was selected for further investigation. Itch intensity induced by two challenge agents (cowhage and histamine was assessed on the Computerised Visual Analogue Scale. The difference in average itch intensity (Weighted Mean Over 15 Mins between the 3% dose of SB705498 and placebo for the cowhage challenge was -0.64, whilst the histamine challenge showed on average a -4.65 point change.The 3% topical formulation of SB705498 cream was clinically well tolerated and had target specific pharmacodynamic activity. However there were no clinically significant differences on pruritus induced by either challenge agent in comparison to placebo. SB705498 is unlikely to be of symptomatic benefit for histaminergic or non-histaminergic induced

  4. The ability of H1 or H2 receptor antagonists or their combination in counteracting the glucocorticoid-induced alveolar bone loss in rats.

    Science.gov (United States)

    Ezzat, Bassant A; Abbass, Marwa M S

    2014-02-01

    The aim of the present study was to compare between three possible osteoporotic treatments in prevention of glucocorticoid-induced alveolar bone loss. Fifty adult female Wistar rats with an average weight 150-200 g were randomized into five groups: group I (control) was intraperitoneally injected with saline. The other experimental groups (II & III, IV & V) were intraperitoneally injected with 200 µg/100 g body weight dexamethasone. The experimental groups III, IV and V received intraperitoneal injection of 10 mg/kg/day pheniramine maleate (H1 receptor antagonist), ranitidine hydrochloride (H2 receptor antagonist) and concomitant doses of both H1 & H2 receptor antagonists respectively. After 30 days, the rats have been sacrificed. The mandibles were examined histologically, histochemically and histomorphometrically. The bone mineral density was measured using dual-energy X-ray absorptiometry (DEXA). Histopathologically the glucocorticoid group showed wide medullary cavities with wide osteocytic lacunae. These marrow cavities were reduced in the prophylactic groups (III, IV) but increased in group V. Bone histomorphometric analysis revealed improvement in static bone parameters in groups III and IV and deterioration in group V in comparison to group II. The DEXA revealed significant reduction in the bone mineral density in all experimental groups compared to the control group. In a rat model, the administration of H1 or H2 receptor antagonists separately could minimize the alveolar bone loss caused by the administration of glucocorticoids while concomitant administration of both H1 and H2 receptor antagonists deteriorated the bone condition. © 2013 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  5. Necrose cutânea induzida por antagonistas da vitamina K Skin necrosis induced by vitamin K antagonists

    Directory of Open Access Journals (Sweden)

    Jose Manoel da Silva Silvestre

    2009-12-01

    Full Text Available Os anticoagulantes orais que atuam através do antagonismo à vitamina K são utilizados na prática clínica há muito tempo, porém ainda há dificuldades no seu manejo e na condução das complicações. Entre as complicações, as mais conhecidas são os transtornos hemorrágicos, mas outras também devem ser reconhecidas, tais como a necrose induzida por varfarina. Esta é uma grave, porém rara complicação, cuja fisiopatologia é ainda obscura e cujas causas são indefinidas. Dentre as possíveis causas, as mais prováveis são a deficiência de proteína C e de proteína S, reações de hipersensibilidade e deficiência de fator VII. Há maior incidência desta complicação entre mulheres de meia-idade, acometendo preferencialmente mamas e glúteos. As medidas mais importantes para o tratamento são: suspensão imediata da droga, uso de heparina não fracionada ou de baixo peso molecular em doses terapêuticas, emprego da vitamina K e, eventualmente, infusão de plasma fresco congelado ou de proteína C ativada recombinante.Oral anticoagulants acting via vitamin K antagonists have long been employed in the clinical practice. However, difficulties related to the management of treatment regimens and complications still persist. Among the complications, bleeding disorders are widely known, but others should also be taken into consideration, such as warfarin-induced skin necrosis. The pathophysiology of this rare but severe complication is still obscure, and its causes remain to be defined. Among possible causes, protein C and protein S deficiency, hypersensitivity reactions and VII factor deficiency are the most probable ones. There is an increased incidence of warfarin-induced skin necrosis among middle-aged women, usually affecting breasts and buttocks. The most important treatment measures are immediate discontinuation of the drug, use of unfractionated or low-molecular-weight heparin at therapeutic doses, use of vitamin K and

  6. Effect of glycine site/NMDA receptor antagonist MRZ2/576 on the conditioned place preference and locomotor activity induced by morphine in mice*

    OpenAIRE

    Zhu, Yong-ping; Long, Zai-hao; Zheng, Ming-lan; Binsack, Ralf

    2006-01-01

    Objective: To study the effect of glycine site/NMDA (N-methyl-D-aspartate) receptor antagonist MRZ2/576 on the conditioned place preference (CPP) and locomotor activity induced by morphine in mice. Methods: Different doses (1.25, 2.5 and 5 mg/kg, i.p.) of MRZ2/576 were used to evaluate the effect of MRZ2/576 on the acquisition and expression of CPP induced by morphine (5 mg/kg) in mice. In addition, we examined the locomotor activity of mice in conditioning and testing phase of CPP paradigm. ...

  7. Peripherally Administered Y2-Receptor Antagonist BIIE0246 Prevents Diet-Induced Obesity in Mice With Excess Neuropeptide Y, but Enhances Obesity in Control Mice.

    Science.gov (United States)

    Ailanen, Liisa; Vähätalo, Laura H; Salomäki-Myftari, Henriikka; Mäkelä, Satu; Orpana, Wendy; Ruohonen, Suvi T; Savontaus, Eriika

    2018-01-01

    Neuropeptide Y (NPY) plays an important role in the regulation of energy homeostasis in the level of central and sympathetic nervous systems (SNSs). Genetic silencing of peripheral Y 2 -receptors have anti-obesity effects, but it is not known whether pharmacological blocking of peripheral Y 2 -receptors would similarly benefit energy homeostasis. The effects of a peripherally administered Y 2 -receptor antagonist were studied in healthy and energy-rich conditions with or without excess NPY. Genetically obese mice overexpressing NPY in brain noradrenergic nerves and SNS (OE-NPY DβH ) represented the situation of elevated NPY levels, while wildtype (WT) mice represented the normal NPY levels. Specific Y 2 -receptor antagonist, BIIE0246, was administered (1.3 mg/kg/day, i.p.) for 2 or 4.5 weeks to OE-NPY DβH and WT mice feeding on chow or Western diet. Treatment with Y 2 -receptor antagonist increased body weight gain in both genotypes on chow diet and caused metabolic disturbances (e.g., hyperinsulinemia and hypercholesterolemia), especially in WT mice. During energy surplus (i.e., on Western diet), blocking of Y 2 -receptors induced obesity in WT mice, whereas OE-NPY DβH mice showed reduced fat mass gain, hepatic glycogen and serum cholesterol levels relative to body adiposity. Thus, it can be concluded that with normal NPY levels, peripheral Y 2 -receptor antagonist has no potential for treating obesity, but oppositely may even induce metabolic disorders. However, when energy-rich diet is combined with elevated NPY levels, e.g., stress combined with an unhealthy diet, Y 2 -receptor antagonism has beneficial effects on metabolic status.

  8. RF313, an orally bioavailable neuropeptide FF receptor antagonist, opposes effects of RF-amide-related peptide-3 and opioid-induced hyperalgesia in rodents.

    Science.gov (United States)

    Elhabazi, Khadija; Humbert, Jean-Paul; Bertin, Isabelle; Quillet, Raphaelle; Utard, Valérie; Schneider, Séverine; Schmitt, Martine; Bourguignon, Jean-Jacques; Laboureyras, Emilie; Ben Boujema, Meric; Simonnet, Guy; Ancel, Caroline; Simonneaux, Valérie; Beltramo, Massimiliano; Bucher, Bernard; Sorg, Tania; Meziane, Hamid; Schneider, Elodie; Petit-Demoulière, Benoit; Ilien, Brigitte; Bihel, Frédéric; Simonin, Frédéric

    2017-05-15

    Although opiates represent the most effective analgesics, their use in chronic treatments is associated with numerous side effects including the development of pain hypersensitivity and analgesic tolerance. We recently identified a novel orally active neuropeptide FF (NPFF) receptor antagonist, RF313, which efficiently prevents the development of fentanyl-induced hyperalgesia in rats. In this study, we investigated the properties of this compound into more details. We show that RF313 exhibited a pronounced selectivity for NPFF receptors, antagonist activity at NPFF1 receptor (NPFF1R) subtype both in vitro and in vivo and no major side effects when administered in mice up to 30 mg/kg. When co-administered with opiates in rats and mice, it improved their analgesic efficacy and prevented the development of long lasting opioid-induced hyperalgesia. Moreover, and in marked contrast with the dipeptidic NPFF receptor antagonist RF9, RF313 displayed negligible affinity and no agonist activity (up to 100 μM) toward the kisspeptin receptor. Finally, in male hamster, RF313 had no effect when administered alone but fully blocked the increase in LH induced by RFRP-3, while RF9 per se induced a significant increase in LH levels which is consistent with its ability to activate kisspeptin receptors. Altogether, our data indicate that RF313 represents an interesting compound for the development of therapeutic tools aiming at improving analgesic action of opiates and reducing adverse side effects associated with their chronic administration. Moreover, its lack of agonist activity at the kisspeptin receptor indicates that RF313 might be considered a better pharmacological tool, when compared to RF9, to examine the regulatory roles of RF-amide-related peptides and NPFF1R in reproduction. Copyright © 2017 Elsevier Ltd. All rights reserved.

  9. Pharmacological properties of S1RA, a new sigma-1 receptor antagonist that inhibits neuropathic pain and activity-induced spinal sensitization.

    Science.gov (United States)

    Romero, L; Zamanillo, D; Nadal, X; Sánchez-Arroyos, R; Rivera-Arconada, I; Dordal, A; Montero, A; Muro, A; Bura, A; Segalés, C; Laloya, M; Hernández, E; Portillo-Salido, E; Escriche, M; Codony, X; Encina, G; Burgueño, J; Merlos, M; Baeyens, J M; Giraldo, J; López-García, J A; Maldonado, R; Plata-Salamán, C R; Vela, J M

    2012-08-01

    The sigma-1 (σ(1) ) receptor is a ligand-regulated molecular chaperone that has been involved in pain, but there is limited understanding of the actions associated with its pharmacological modulation. Indeed, the selectivity and pharmacological properties of σ(1) receptor ligands used as pharmacological tools are unclear and the demonstration that σ(1) receptor antagonists have efficacy in reversing central sensitization-related pain sensitivity is still missing. The pharmacological properties of a novel σ(1) receptor antagonist (S1RA) were first characterized. S1RA was then used to investigate the effect of pharmacological antagonism of σ(1) receptors on in vivo nociception in sensitizing conditions and on in vitro spinal cord sensitization in mice. Drug levels and autoradiographic, ex vivo binding for σ(1) receptor occupancy were measured to substantiate behavioural data. Formalin-induced nociception (both phases), capsaicin-induced mechanical hypersensitivity and sciatic nerve injury-induced mechanical and thermal hypersensitivity were dose-dependently inhibited by systemic administration of S1RA. Occupancy of σ(1) receptors in the CNS was significantly correlated with the antinociceptive effects. No pharmacodynamic tolerance to the antiallodynic and antihyperalgesic effect developed following repeated administration of S1RA to nerve-injured mice. As a mechanistic correlate, electrophysiological recordings demonstrated that pharmacological antagonism of σ(1) receptors attenuated the wind-up responses in spinal cords sensitized by repetitive nociceptive stimulation. These findings contribute to evidence identifying the σ(1) receptor as a modulator of activity-induced spinal sensitization and pain hypersensitivity, and suggest σ(1) receptor antagonists as potential novel treatments for neuropathic pain. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  10. The cholecystokinin-B receptor antagonist CI-988 failed to affect CCK-4 induced symptoms in panic disorder patients

    NARCIS (Netherlands)

    vanMegen, HJGM; Westenberg, HGM; denBoer, JA; Slaap, B; vanEsRadhakishun, F; Pande, AC

    The effects of the cholecystokinin-B (CCK-B) receptor antagonist CI-988 on symptoms elicited by the cholecystokinin tetrapeptide (CCK4) were studied in DSM-IIIR patients with panic disorder. The study employed a double-blind, two-period incomplete block design. Patients (n = 14) received two

  11. Caffeine and a selective adenosine A2A receptor antagonist induce sensitization and cross-sensitization behavior associated with increased striatal dopamine in mice

    Directory of Open Access Journals (Sweden)

    Hsu Chih W

    2010-01-01

    Full Text Available Abstract Background Caffeine, a nonselective adenosine A1 and A2A receptor antagonist, is the most widely used psychoactive substance in the world. Evidence demonstrates that caffeine and selective adenosine A2A antagonists interact with the neuronal systems involved in drug reinforcement, locomotor sensitization, and therapeutic effect in Parkinson's disease (PD. Evidence also indicates that low doses of caffeine and a selective adenosine A2A antagonist SCH58261 elicit locomotor stimulation whereas high doses of these drugs exert locomotor inhibition. Since these behavioral and therapeutic effects are mediated by the mesolimbic and nigrostriatal dopaminergic pathways which project to the striatum, we hypothesize that low doses of caffeine and SCH58261 may modulate the functions of dopaminergic neurons in the striatum. Methods In this study, we evaluated the neuroadaptations in the striatum by using reverse-phase high performance liquid chromatography (HPLC to quantitate the concentrations of striatal dopamine and its metabolites, dihydroxylphenylacetic acid (DOPAC and homovanilic acid (HVA, and using immunoblotting to measure the level of phosphorylation of tyrosine hydroxylase (TH at Ser31, following chronic caffeine and SCH58261 sensitization in mice. Moreover, to validate further that the behavior sensitization of caffeine is through antagonism at the adenosine A2A receptor, we also evaluate whether chronic pretreatment with a selective adenosine A2A antagonist SCH58261 or a selective adenosine A1 antagonist DPCPX can sensitize the locomotor stimulating effects of caffeine. Results Chronic treatments with low dose caffeine (10 mg/kg or SCH58261 (2 mg/kg increased the concentrations of dopamine, DOPAC and HVA, concomitant with increased TH phosphorylation at Ser31 and consequently enhanced TH activity in the striatal tissues in both caffeine- and SCH58261-sensitized mice. In addition, chronic caffeine or SCH58261 administration induced

  12. The Histamine H3 Receptor Antagonist E159 Reverses Memory Deficits Induced by Dizocilpine in Passive Avoidance and Novel Object Recognition Paradigm in Rats

    Directory of Open Access Journals (Sweden)

    Alaa Alachkar

    2017-10-01

    Full Text Available The involvement of histamine H3 receptors (H3Rs in memory is well known, and the potential of H3R antagonists in therapeutic management of neuropsychiatric diseases, e.g., Alzheimer disease (AD is well established. Therefore, the effects of histamine H3 receptor (H3R antagonist E159 (2.5–10 mg/kg, i.p. in adult male rats on dizocilpine (DIZ-induced memory deficits were studied in passive avoidance paradigm (PAP and in novel object recognition (NOR using pitolisant (PIT and donepezil (DOZ as standard drugs. Upon acute systemic pretreatment of E159 at three different doses, namely 2.5, 5, and 10 mg/kg, i.p., 2.5 and 5 but not 10 mg/kg of E159 counteracted the DIZ (0.1 mg-induced memory deficits, and this E159 (2.5 mg-elicited memory-improving effects in DIZ-induced amnesic model were moderately abrogated after acute systemic administration of scopolamine (SCO, H2R antagonist zolantidine (ZOL, but not with H1R antagonist pyrilamine to the animals. Moreover, the observed memory-enhancing effects of E159 (2.5 mg/kg, i.p. were strongly abrogated when animals were administered with a combination of SCO and ZOL. Furthermore, the E159 (2.5 mg-provided significant memory-improving effect of in DIZ-induced short-term memory (STM impairment in NOR was comparable to the DOZ-provided memory-enhancing effect, and was abolished when animals were injected with the CNS-penetrant histamine H3R agonist R-(α-methylhistamine (RAMH. However, E159 at a dose of 2.5 mg/kg failed to exhibit procognitive effect on DIZ-induced long-term memory (LTM in NOR. Furthermore, the results observed revealed that E159 (2.5 mg/kg did not alter anxiety levels and locomotor activity of animals naive to elevated-plus maze (EPM, demonstrating that improved performances with E159 (2.5 mg/kg in PAP or NOR are unrelated to changes in emotional responding or in spontaneous locomotor activity. These results provide evidence for the potential of drugs targeting H3Rs for the treatment of

  13. 2,8-Diazaspiro[4.5]decan-8-yl)pyrimidin-4-amine potent CCR4 antagonists capable of inducing receptor endocytosis.

    Science.gov (United States)

    Shukla, Lena; Ajram, Laura A; Begg, Malcolm; Evans, Brian; Graves, Rebecca H; Hodgson, Simon T; Lynn, Sean M; Miah, Afjal H; Percy, Jonathan M; Procopiou, Panayiotis A; Richards, Stephen A; Slack, Robert J

    2016-06-10

    A number of potent 2,8-diazaspiro[4.5]decan-8-yl)pyrimidin-4-amine CCR4 antagonists binding to the extracellular allosteric site were synthesised. (R)-N-(2,4-Dichlorobenzyl)-2-(2-(pyrrolidin-2-ylmethyl)-2,8-diazaspiro[4.5]decan-8-yl)pyrimidin-4-amine (R)-(18a) has high affinity in both the [(125)I]-TARC binding assay with a pKi of 8.8, and the [(35)S]-GTPγS functional assay with a pIC50 of 8.1, and high activity in the human whole blood actin polymerisation assay (pA2 = 6.7). The most potent antagonists were also investigated for their ability to induce endocytosis of CCR4 and were found to internalise about 60% of the cell surface receptors, a property which is not commonly shared by small molecule antagonists of chemokine receptors. Copyright © 2016 Elsevier Masson SAS. All rights reserved.

  14. GABAB antagonists

    DEFF Research Database (Denmark)

    Frydenvang, Karla Andrea; Hansen, J J; Krogsgaard-Larsen, P

    1994-01-01

    chromatographic techniques. The absolute stereochemistry of (-)-(R)-phaclofen was established by X-ray crystallographic analysis. (-)-(R)-Phaclofen was shown to inhibit the binding of [3H]-(R)-baclofen to GABAB receptor sites on rat cerebellar membranes (IC50 = 76 +/- 13 microM), whereas (+)-(S......)-baclofen and the antagonist (-)-(R)-phaclofen suggests that these ligands interact with the GABAB receptor sites in a similar manner. Thus, it may be concluded that the different pharmacological effects of these compounds essentially result from the different spatial and proteolytic properties of their acid groups....

  15. Novel Peripherally Restricted Cannabinoid 1 Receptor Selective Antagonist TXX-522 with Prominent Weight-Loss Efficacy in Diet Induced Obese Mice

    Directory of Open Access Journals (Sweden)

    Wei Chen

    2017-10-01

    Full Text Available The clinical development of the first generation of globally active cannabinoid 1 receptor (CB1R antagonists was suspended because of their adverse neuropsychiatric effects. Selective blockade of peripheral CB1Rs has the potential to provide a viable strategy for the treatment of severe obesity while avoiding these central nervous system side effects. In the current study, a novel compound (TXX-522 was rationally designed based on the parent nucleus of a classical CB1R-selective antagonist/inverse agonist, rimonabant (SR141716A. Docking assays indicate that TXX-522 was bound with the CB1R in a mode similar to that of SR141716A. TXX-522 showed good binding, CB1R-selectivity (over the CB2R, and functional antagonist activities in a range of in vitro molecular and cellular assays. In vivo analysis of the steady state distribution of TXX-522 in the rat brain and blood tissues and the assay of its functional effects on CB1R activity collectively showed that TXX-522 showed minimal brain penetration. Moreover, the in vivo pharmacodynamic study further revealed that TXX-522 had good oral bioavailability and a potent anti-obesity effect, and ameliorated insulin resistance in high-fat diet-induced obese mice. No impact on food intake was observed in this model, confirming the limited brain penetration of this compound. Thus, the current study indicates that TXX-522 is a novel and potent peripherally acting selective CB1R antagonist with the potential to control obesity and related metabolic disorders.

  16. Characterization of cutaneous vascular permeability induced by platelet-activating factor in guinea pigs and rats and its inhibition by a platelet-activating factor receptor antagonist

    Energy Technology Data Exchange (ETDEWEB)

    Hwang, S.B.; Li, C.L.; Lam, M.H.; Shen, T.Y.

    1985-06-01

    Mechanisms of platelet-activating factor (PAF)-induced increases of cutaneous vascular permeability in guinea pigs and in rats were further explored. PAF so far is the most potent vasoactive mediator, being more than 1000-fold more potent than histamine and bradykinin in both species. In guinea pigs, there is a time delay of 5 to 10 minutes before PAF action, whereas, in the rat, the increased vasopermeability occurs immediately following the intradermal PAF injection. Relative vasoactive potencies of PAF and several structure-related analogues in both species correlate very well with their relative inhibition of the binding of /sup 3/H-PAF to specific receptor sites on isolated rabbit platelet plasma membranes and their aggregatory abilities of rabbit platelets. Furthermore, the PAF-induced cutaneous vascular permeability is inhibitable by a competitive specific PAF receptor antagonist, kadsurenone, suggesting that binding of PAF to its specific receptor site is the first step to initiate its action of increased cutaneous vascular permeability. Several pure cyclooxygenase inhibitors, including indomethacin, diflunisal, and flurbiprofen, and the dual cyclooxygenase/lipoxygenase inhibitor, BW755C, but not the histamine antagonists, inhibit the PAF-induced vasopermeability in guinea pigs. The inhibition by indomethacin or BW755C can be fully reversed by coinjection intradermally with PAF and prostaglandin E1 but not leukotriene B4. Also, prostaglandin E1 but not leukotriene B4 enhances the guinea pig in vivo response to PAF in this model. However, in rats, none of the cyclooxygenase inhibitors, histamine antagonists, or BW755C inhibit the PAF effect of cutaneous phenomena.

  17. Characterization of cutaneous vascular permeability induced by platelet-activating factor in guinea pigs and rats and its inhibition by a platelet-activating factor receptor antagonist

    International Nuclear Information System (INIS)

    Hwang, S.B.; Li, C.L.; Lam, M.H.; Shen, T.Y.

    1985-01-01

    Mechanisms of platelet-activating factor (PAF)-induced increases of cutaneous vascular permeability in guinea pigs and in rats were further explored. PAF so far is the most potent vasoactive mediator, being more than 1000-fold more potent than histamine and bradykinin in both species. In guinea pigs, there is a time delay of 5 to 10 minutes before PAF action, whereas, in the rat, the increased vasopermeability occurs immediately following the intradermal PAF injection. Relative vasoactive potencies of PAF and several structure-related analogues in both species correlate very well with their relative inhibition of the binding of 3 H-PAF to specific receptor sites on isolated rabbit platelet plasma membranes and their aggregatory abilities of rabbit platelets. Furthermore, the PAF-induced cutaneous vascular permeability is inhibitable by a competitive specific PAF receptor antagonist, kadsurenone, suggesting that binding of PAF to its specific receptor site is the first step to initiate its action of increased cutaneous vascular permeability. Several pure cyclooxygenase inhibitors, including indomethacin, diflunisal, and flurbiprofen, and the dual cyclooxygenase/lipoxygenase inhibitor, BW755C, but not the histamine antagonists, inhibit the PAF-induced vasopermeability in guinea pigs. The inhibition by indomethacin or BW755C can be fully reversed by coinjection intradermally with PAF and prostaglandin E1 but not leukotriene B4. Also, prostaglandin E1 but not leukotriene B4 enhances the guinea pig in vivo response to PAF in this model. However, in rats, none of the cyclooxygenase inhibitors, histamine antagonists, or BW755C inhibit the PAF effect of cutaneous phenomena

  18. Pre-treatment with Toll-like receptor 4 antagonist inhibits lipopolysaccharide-induced preterm uterine contractility, cytokines, and prostaglandins in rhesus monkeys

    Science.gov (United States)

    Adams Waldorf, Kristina M.; Persing, David; Novy, Miles J.; Sadowsky, Drew W.; Gravett, Michael G.

    2009-01-01

    Intra-uterine infection, which occurs in the majority of early preterm births, triggers an immune response culminating in preterm labor. We hypothesized that blockade of lipopolysaccharide (LPS)-induced immune responses by a Toll-like receptor 4 antagonist (TLR4A) would prevent elevations in amniotic fluid (AF) cytokines, prostaglandins, and uterine contractility. Chronically catheterized rhesus monkeys at 128-147 days gestation received intra-amniotic infusions of either: 1) saline (n=6), 2) LPS (0.15-10μg; n=4), or 3) TLR4A pre-treatment with LPS (10 μg) one hour later (n=4). AF cytokines, prostaglandins, and uterine contractility were compared using oneway ANOVA with Bonferroni-adjusted pairwise comparisons. Compared to saline controls, LPS induced significant elevations in AF IL-8, TNF-α, PGE2, PGF2α, and uterine contractility (p<0.05). In contrast, TLR4A pre-treatment inhibited LPS-induced uterine activity and was associated with significantly lower AF IL-8, TNF-α, PGE2, and PGF2α versus LPS alone (p<0.05). Toll-like receptor antagonists, together with antibiotics, may delay or prevent infection-associated preterm birth. PMID:18187405

  19. Calcium antagonist induced vasodilation in peripheral, coronary and cerebral vasculature as important factors in the treatment of elderly hypertensives

    OpenAIRE

    Erne, P.; Conen, D.; Kiowski, W.; Bolli, P.; Müller, F. B.; Bühler, F. R.

    2017-01-01

    Increased arteriolar tone is the pathophysiological hallmark of essential hypertension and is determined by the intracellular free calcium concentration in the vascular smooth muscle cell. Calcium influx is an important determinant of vasoconstriction and excess calcium influx-dependent vasoconstriction has been shown by plethysmographical studies in patients with essential hypertension. Calcium antagonists acutely lower BP by reducing calcium influx, calcium concentration and peripheral resi...

  20. Systemic administration of an mGluR5 antagonist, but not unilateral subthalamic lesion, counteracts l-DOPA-induced dyskinesias in a rodent model of Parkinson's disease.

    Science.gov (United States)

    Levandis, Giovanna; Bazzini, Eleonora; Armentero, Marie-Thérèse; Nappi, Giuseppe; Blandini, Fabio

    2008-01-01

    Altered glutamatergic neurotransmission is central to the expression of Parkinson's disease (PD) symptoms and may underlie l-DOPA-induced dyskinesias. Drugs acting on glutamate metabotropic receptors (mGluR) of group I can modulate subthalamic nucleus (STN) overactivity, which plays a pivotal role in these phenomena, and may counteract dyskinesias. To address these issues, we investigated the effects of a 3-week treatment with mGluR5 antagonist 2-methyl-6-(phenylethynyl)-pyridine (MPEP), or of a subthalamic lesion, on abnormal involuntary movements (AIMs) and associated striatal expression of transcription factor FosB/Delta FosB caused by chronic l-DOPA administration, in rats with a nigrostriatal lesion. MPEP virtually abolished AIMs and reduced, dramatically, striatal expression of FosB/Delta FosB. Reduced FosB/Delta FosB expression, coupled with nonsignificant reduction of AIMs, was also observed in STN-lesioned rats. Our data confirm the role of glutamatergic neurotransmission in the pathogenesis of dyskinesias and the potential of mGluR5 antagonists in the treatment of l-DOPA-induced dyskinesias.

  1. Influenza A virus does not encode a tetherin antagonist with Vpu-like activity and induces IFN-dependent tetherin expression in infected cells.

    Directory of Open Access Journals (Sweden)

    Michael Winkler

    Full Text Available The interferon-induced host cell factor tetherin inhibits release of human immunodeficiency virus (HIV from the plasma membrane of infected cells and is counteracted by the HIV-1 protein Vpu. Influenza A virus (FLUAV also buds from the plasma membrane and is not inhibited by tetherin. Here, we investigated if FLUAV encodes a functional equivalent of Vpu for tetherin antagonism. We found that expression of the FLUAV protein NS1, which antagonizes the interferon (IFN response, did not block the tetherin-mediated restriction of HIV release, which was rescued by Vpu. Similarly, tetherin-mediated inhibition of HIV release was not rescued by FLUAV infection. In contrast, FLUAV infection induced tetherin expression on target cells in an IFN-dependent manner. These results suggest that FLUAV escapes the antiviral effects of tetherin without encoding a tetherin antagonist with Vpu-like activity.

  2. The Effects of the Adenosine Receptor Antagonists on the Reverse of Cardiovascular Toxic Effects Induced by Citalopram In-Vivo Rat Model of Poisoning

    Directory of Open Access Journals (Sweden)

    Müjgan Büyükdeligöz

    2015-09-01

    Full Text Available Background: Citalopram is a selective serotonin reuptake inhibitor that requires routine cardiac monitoring to prevent a toxic dose. Prolongation of the QT interval has been observed in acute citalopram poisoning. Our previous experimental study showed that citalopram may be lead to QT prolongation by stimulating adenosine A1 receptors without affecting the release of adenosine. Aims: We examined the effects of adenosine receptor antagonists in reversing the cardiovascular toxic effects induced by citalopram in rats. Study Design: Animal experimentation. Methods: Rats were divided into three groups randomly (n=7 for each group. Sodium cromoglycate (20 mg/kg was administered to all rats to inhibit adenosine A3 receptor mast cell activation. Citalopram toxicity was achieved by citalopram infusion (4 mg/kg/min for 20 minutes. After citalopram infusion, in the control group (Group 1, rats were given an infusion of dextrose solution for 60 minutes. In treatment groups, the selective adenosine A1 antagonist DPCPX (Group 2, 8-cyclopentyl-1,3-dipropylxanthine, 20 μg/kg/min or the selective A2a antagonist CSC (Group 3, 8-(3-chlorostyrylcaffeine, 24 μg/kg/min was infused for 60 minutes. Mean arterial pressure (MAP, heart rate (HR, QRS duration and QT interval measurements were followed during the experiment period. Statistical analysis was performed by ANOVA followed by Tukey’s multiple comparison tests. Results: Citalopram infusion reduced MAP and HR and prolonged the QT interval. It did not cause any significant difference in QRS duration in any group. When compared to the control group, DPCPX after citalopram infusion shortened the prolongation of the QT interval after 40, 50 and 60 minutes (p<0.01. DPCPX infusion shortened the prolongation of the QT interval at 60 minutes compared with the CSC group (p<0.05. CSC infusion shortened the prolongation of the QT at 60 minutes compared with the control group (p<0.05. Conclusion: DPCPX improved QT

  3. Stress-Induced In Vivo Recruitment of Human Cytotoxic Natural Killer Cells Favors Subsets with Distinct Receptor Profiles and Associates with Increased Epinephrine Levels.

    Directory of Open Access Journals (Sweden)

    Marc B Bigler

    Full Text Available Acute stress drives a 'high-alert' response in the immune system. Psychoactive drugs induce distinct stress hormone profiles, offering a sought-after opportunity to dissect the in vivo immunological effects of acute stress in humans.3,4-methylenedioxymethamphetamine (MDMA, methylphenidate (MPH, or both, were administered to healthy volunteers in a randomized, double-blind, placebo-controlled crossover-study. Lymphocyte subset frequencies, natural killer (NK cell immune-phenotypes, and changes in effector function were assessed, and linked to stress hormone levels and expression of CD62L, CX3CR1, CD18, and stress hormone receptors on NK cells.MDMA/MPH > MDMA > MPH robustly induced an epinephrine-dominant stress response. Immunologically, rapid redistribution of peripheral blood lymphocyte-subsets towards phenotypically mature NK cells occurred. NK cytotoxicity was unaltered, but they expressed slightly reduced levels of the activating receptor NKG2D. Preferential circulation of mature NK cells was associated with high epinephrine receptor expression among this subset, as well as expression of integrin ligands previously linked to epinephrine-induced endothelial detachment.The acute epinephrine-induced stress response was characterized by rapid accumulation of mature and functional NK cells in the peripheral circulation. This is in line with studies using other acute stressors and supports the role of the acute stress response in rapidly mobilizing the innate immune system to counteract incoming threats.

  4. Intrauterine Zn Deficiency Favors Thyrotropin-Releasing Hormone-Increasing Effects on Thyrotropin Serum Levels and Induces Subclinical Hypothyroidism in Weaned Rats

    Directory of Open Access Journals (Sweden)

    Viridiana Alcántara-Alonso

    2017-10-01

    Full Text Available Individuals who consume a diet deficient in zinc (Zn-deficient develop alterations in hypothalamic-pituitary-thyroid axis function, i.e., a low metabolic rate and cold insensitivity. Although those disturbances are related to primary hypothyroidism, intrauterine or postnatal Zn-deficient adults have an increased thyrotropin (TSH concentration, but unchanged thyroid hormone (TH levels and decreased body weight. This does not support the view that the hypothyroidism develops due to a low Zn intake. In addition, intrauterine or postnatal Zn-deficiency in weaned and adult rats reduces the activity of pyroglutamyl aminopeptidase II (PPII in the medial-basal hypothalamus (MBH. PPII is an enzyme that degrades thyrotropin-releasing hormone (TRH. This hypothalamic peptide stimulates its receptor in adenohypophysis, thereby increasing TSH release. We analyzed whether earlier low TH is responsible for the high TSH levels reported in adults, or if TRH release is enhanced by Zn deficiency at weaning. Dams were fed a 2 ppm Zn-deficient diet in the period from one week prior to gestation and up to three weeks after delivery. We found a high release of hypothalamic TRH, which along with reduced MBH PPII activity, increased TSH levels in Zn-deficient pups independently of changes in TH concentration. We found that primary hypothyroidism did not develop in intrauterine Zn-deficient weaned rats and we confirmed that metal deficiency enhances TSH levels since early-life, favoring subclinical hypothyroidism development which remains into adulthood.

  5. Novel 5-HT5A receptor antagonists ameliorate scopolamine-induced working memory deficit in mice and reference memory impairment in aged rats

    Directory of Open Access Journals (Sweden)

    Mayako Yamazaki

    2015-03-01

    Full Text Available Despite the human 5-HT5A receptor being cloned in 1994, the biological function of this receptor has not been extensively characterized due to a lack of specific ligands. We recently reported that the selective 5-HT5A receptor antagonist ASP5736 ameliorated cognitive impairment in several animal models of schizophrenia. Given that areas of the brain with high levels of 5-HT5A receptor expression, such as the hippocampus and cerebral cortex, have important functions in cognition and memory, we evaluated the chemically diverse, potent and brain-penetrating 5-HT5A receptor antagonists ASP5736, AS2030680, and AS2674723 in rodent models of cognitive dysfunction associated with dementia. Each of these compounds exhibited a high affinity for recombinant 5-HT5A receptors that was comparable to that of the non-selective ligand of this receptor, lysergic acid diethylamide (LSD. Although each compound had a low affinity for other receptors, 5-HT5A was the only receptor for which all three compounds had a high affinity. Each of the three compounds ameliorated scopolamine-induced working memory deficit in mice and improved reference memory impairment in aged rats at similar doses. Further, ASP5736 decreased the binding of LSD to 5-HT5A receptors in the olfactory bulb of rats in a dose-dependent manner and occupied 15%–50% of brain 5-HT5A receptors at behaviorally effective doses. These results indicate that the 5-HT5A receptor is involved in learning and memory and that treatment with 5-HT5A receptor antagonists might be broadly effective for cognitive impairment associated with not only schizophrenia but also dementia.

  6. Novel 5-HT5A receptor antagonists ameliorate scopolamine-induced working memory deficit in mice and reference memory impairment in aged rats.

    Science.gov (United States)

    Yamazaki, Mayako; Okabe, Mayuko; Yamamoto, Noriyuki; Yarimizu, Junko; Harada, Katsuya

    2015-03-01

    Despite the human 5-HT5A receptor being cloned in 1994, the biological function of this receptor has not been extensively characterized due to a lack of specific ligands. We recently reported that the selective 5-HT5A receptor antagonist ASP5736 ameliorated cognitive impairment in several animal models of schizophrenia. Given that areas of the brain with high levels of 5-HT5A receptor expression, such as the hippocampus and cerebral cortex, have important functions in cognition and memory, we evaluated the chemically diverse, potent and brain-penetrating 5-HT5A receptor antagonists ASP5736, AS2030680, and AS2674723 in rodent models of cognitive dysfunction associated with dementia. Each of these compounds exhibited a high affinity for recombinant 5-HT5A receptors that was comparable to that of the non-selective ligand of this receptor, lysergic acid diethylamide (LSD). Although each compound had a low affinity for other receptors, 5-HT5A was the only receptor for which all three compounds had a high affinity. Each of the three compounds ameliorated scopolamine-induced working memory deficit in mice and improved reference memory impairment in aged rats at similar doses. Further, ASP5736 decreased the binding of LSD to 5-HT5A receptors in the olfactory bulb of rats in a dose-dependent manner and occupied 15%-50% of brain 5-HT5A receptors at behaviorally effective doses. These results indicate that the 5-HT5A receptor is involved in learning and memory and that treatment with 5-HT5A receptor antagonists might be broadly effective for cognitive impairment associated with not only schizophrenia but also dementia. Copyright © 2015 The Authors. Production and hosting by Elsevier B.V. All rights reserved.

  7. Kindling-induced potentiation of excitatory and inhibitory inputs to hippocampal dentate granule cells. II. Effects of the NMDA antagonist MK-801.

    LENUS (Irish Health Repository)

    Robinson, G B

    1991-10-18

    The effect of the non-competitive N-methyl-D-aspartate antagonist MK-801 on the early development of kindling-induced potentiation was examined in the rabbit hippocampal dentate gyrus. MK-801 (0.5 mg\\/kg) was administered 2 h before each daily kindling stimulation was applied to the perforant path. This treatment continued for the first 10 days of kindling. MK-801 depressed the growth of the afterdischarge duration and suppressed development of behavioral seizures. MK-801 did not block kindling-induced potentiation of either the perforant path-dentate granule cell population spike or excitatory postsynaptic potential. Random impulse train stimulation and non-linear systems analytic techniques were used to examine kindling-induced potentiation of presumed GABAergic recurrent inhibitory circuits. Both the magnitude and duration of kindling-induced response inhibition, to the second of each pair of impulses within the train, were reduced in rabbits pretreated with MK-801. These results suggest that MK-801 differentially affects kindling-induced potentiation of excitatory and inhibitory circuits within the rabbit hippocampal dentate gyrus.

  8. Selective A2A receptor antagonist prevents microglia-mediated neuroinflammation and protects retinal ganglion cells from high intraocular pressure-induced transient ischemic injury.

    Science.gov (United States)

    Madeira, Maria H; Boia, Raquel; Elvas, Filipe; Martins, Tiago; Cunha, Rodrigo A; Ambrósio, António Francisco; Santiago, Ana Raquel

    2016-03-01

    Glaucoma is a leading cause of vision loss and blindness worldwide, characterized by chronic and progressive neuronal loss. Reactive microglial cells have been recognized as a neuropathologic feature, contributing to local inflammation and retinal neurodegeneration. In a recent in vitro work (organotypic cultures), we demonstrated that blockade of adenosine A2A receptor (A2AR) prevents the neuroinflammatory response and affords protection to retinal ganglion cells (RGCs) against exposure to elevated hydrostatic pressure (EHP), to mimic elevated intraocular pressure (IOP), the main risk factor for glaucoma development. Herein, we investigated whether a selective A2AR antagonist (SCH 58261) could modulate retinal microglia reactivity and their inflammatory response. Furthermore, we took advantage of the high IOP-induced transient ischemia (ischemia-reperfusion, I-R) animal model to evaluate the protective role of A2AR blockade in the control of retinal neuroinflammation and neurodegeneration. Primary microglial cell cultures were challenged either with lipopolysaccharide or with EHP, in the presence or absence of A2AR antagonist SCH 58261 (50 nM). In addition, I-R injury was induced in adult Wistar rats after intravitreal administration of SCH 58261 (100 nM, 5 μL). Our results showed that SCH 58261 attenuated microglia reactivity and the increased expression and release of proinflammatory cytokines. Moreover, intravitreal administration of SCH 58261 prevented I-R-induced cell death and RGC loss, by controlling microglial-mediated neuroinflammatory response. These results prompt the proposal that A2AR blockade may have great potential in the management of retinal neurodegenerative diseases characterized by microglia reactivity and RGC death, such as glaucoma and ischemic diseases. Copyright © 2016 Elsevier Inc. All rights reserved.

  9. Effects of L-type Ca2+ channel antagonists on in vitro excystment of Paragonimus ohirai metacercariae induced by sodium cholate.

    Science.gov (United States)

    Ikeda, Teruaki

    2006-09-01

    The inhibitory effects of L-type Ca2+ channel antagonists on Na cholate-induced in vitro excystment (CIIE) of Paragonimus ohirai metacercariae were studied. At concentrations of 10 microM, nicardipine and nimodipine inhibited CIIE completely and by approximately 92%, respectively. Nitrendipine and (+/-)-verapamil inhibited CIIE by about one half and one third, respectively. Nifedipine and diltiazem did not inhibit CIIE significantly. At higher concentrations, nitrendipine at 20 microM completely inhibited CIIE, and (+/-)-verapamil at 40 microM inhibited CIIE by 93%. Nifedipine and diltiazem inhibited CIIE only slightly and little, respectively, even at 40 microM. Complete inhibition by nicardipine at 10 microM required preincubation of metacercariae with the antagonist for 15 min. The inhibitory effects of nicardipine and nimodipine were reversible, and most of the nimodipine-treated metacercariae could excyst within 1 h after being washed, but the nicardipine-treated ones started to excyst 1 h after washing. Nicardipine suppressed the active movement of encysted juveniles evoked by Na cholate, whereas nimodipine did not suppress this significantly. These results suggested that L-type Ca2+ channels appeared to be involved in CIIE of P. ohirai metacercariae and that the inhibitory effect of the channels was due primarily to factors other than the inhibition of muscular activity, probably involving the secretion and release of enzymes lytic against the metacercarial cyst wall.

  10. The N-Methyl-d-Aspartate Receptor Antagonist MK-801 Prevents Thallium-Induced Behavioral and Biochemical Alterations in the Rat Brain.

    Science.gov (United States)

    Osorio-Rico, Laura; Villeda-Hernández, Juana; Santamaría, Abel; Königsberg, Mina; Galván-Arzate, Sonia

    2015-01-01

    Thallium (Tl(+)) is a toxic heavy metal capable of increasing oxidative damage and disrupting antioxidant defense systems. Thallium invades the brain cells through potassium channels, increasing neuronal excitability, although until now the possible role of glutamatergic transmission in this event has not been investigated. Here, we explored the possible involvement of a glutamatergic component in the Tl(+)-induced toxicity through the N-methyl-d-aspartate (NMDA) receptor antagonist dizocilpine (MK-801) in rats. The effects of MK-801 (1 mg/kg, intraperitoneally [ip]) on early (24 hours) motor alterations, lipid peroxidation, reduced glutathione (GSH) levels, and GSH peroxidase activity induced by Tl(+) acetate (32 mg/kg, ip) were evaluated in adult rats. MK-801 attenuated the Tl(+)-induced hyperactivity and lipid peroxidation in the rat striatum, hippocampus and midbrain, and produced mild effects on other end points. Our findings suggest that glutamatergic transmission via NMDA receptors might be involved in the Tl(+)-induced altered regional brain redox activity and motor performance in rats. © The Author(s) 2015.

  11. The CRF₁ receptor antagonist SSR125543 prevents stress-induced long-lasting sleep disturbances in a mouse model of PTSD: comparison with paroxetine and d-cycloserine.

    Science.gov (United States)

    Philbert, Julie; Beeské, Sandra; Belzung, Catherine; Griebel, Guy

    2015-02-15

    The selective CRF₁ (corticotropin releasing factor type 1) receptor antagonist SSR125543 has been previously shown to attenuate the long-term behavioral and electrophysiological effects produced by traumatic stress exposure in mice. Sleep disturbances are one of the most commonly reported symptoms by people with post-traumatic stress disorder (PTSD). The present study aims at investigating whether SSR125543 (10 mg/kg/day/i.p. for 2 weeks) is able to attenuate sleep/wakefulness impairment induced by traumatic stress exposure in a model of PTSD in mice using electroencephalographic (EEG) analysis. Effects of SSR125543 were compared to those of the 5-HT reuptake inhibitor, paroxetine (10 mg/kg/day/i.p.), and the partial N-methyl-d-aspartate (NMDA) receptor agonist, d-cycloserine (10 mg/kg/day/i.p.), two compounds which have demonstrated clinical efficacy against PTSD. Baseline EEG recording was performed in the home cage for 6h prior to the application of two electric foot-shocks of 1.5 mA. Drugs were administered from day 1 post-stress to the day preceding the second EEG recording session, performed 14 days later. Results showed that at day 14 post-stress, shocked mice displayed sleep fragmentation as shown by an increase in the occurrence of both non-rapid eye movement (NREM) sleep and wakefulness bouts. The duration of wakefulness, NREM and REM sleep were not significantly affected. The stress-induced effects were prevented by repeated administration of SSR125543, paroxetine and D-cycloserine. These findings confirm further that the CRF₁ receptor antagonist SSR125543 is able to attenuate the deleterious effects of traumatic stress exposure. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Influence of the novel histamine H₃ receptor antagonist ST1283 on voluntary alcohol consumption and ethanol-induced place preference in mice.

    Science.gov (United States)

    Bahi, Amine; Sadek, Bassem; Schwed, Stephan J; Walter, Miriam; Stark, Holger

    2013-07-01

    Growing evidence supports a role for the central histaminergic system to have a modulatory influence on drug addiction in general and alcohol-use disorders in particular through histamine H3 receptors (H3R). In the present study, the effects of systemic injection of the newly synthesized H3R antagonist ST1283 on ethanol (EtOH) voluntary intake and EtOH-conditioned reward in mice have been investigated. Oral EtOH, saccharin, and quinine intake was assessed in a two-bottle choice paradigm using escalating concentrations of alcohol or tastant solutions. EtOH-induced place preference (CPP), EtOH-induced locomotor activity, and blood ethanol concentration (BEC) were also measured. Following administration of the H3R antagonist (2.5, 5, and 10 mg/kg, i.p.), there was a significant dose-dependent decrease in alcohol consumption and preference. Importantly, vehicle- and ST1283 (5 mg/kg)-treated mice showed similar consumption and preference to increasing concentration of both sweet and bitter tastes. More interestingly, systemic administration of ST1283 inhibited EtOH-CPP and EtOH-enhanced locomotion. This inhibition was blocked when mice were pretreated with the selective H3R agonist R-(alpha)-methyl-histamine (10 mg/kg). Finally, vehicle- and ST1283-treated mice had similar BECs. Our results show that ST1283 may decrease voluntary EtOH consumption and EtOH-CPP by altering its reinforcing effects, suggesting a novel role for histamine signaling in regulation of alcoholism. Lastly, the results add to the growing literature on H3R modulation in the pharmacotherapy of EtOH addiction.

  13. Tryptophan deprivation induces inhibitory receptors ILT3 and ILT4 on dendritic cells favoring the induction of human CD4+CD25+ Foxp3+ T regulatory cells.

    Science.gov (United States)

    Brenk, Manuela; Scheler, Marina; Koch, Susanne; Neumann, Jürgen; Takikawa, Osamu; Häcker, Georg; Bieber, Thomas; von Bubnoff, Dagmar

    2009-07-01

    Tryptophan catabolism through IDO activity can cause nonresponsiveness and tolerance acting on T cells. Given the crucial importance of dendritic cells (DCs) in the initiation of a T cell response, surprisingly little is known about the impact of IDO activity and tryptophan deprivation on DCs themselves. In the present study, we show that human DCs differentiated under low-tryptophan conditions acquire strong tolerogenic capacity. This effect is associated with a markedly decreased Ag uptake as well as the down-regulation of costimulatory molecules (CD40, CD80). In contrast, the inhibitory receptors ILT3 and ILT4 are significantly increased. Functionally, tryptophan-deprived DCs show a reduced capacity to stimulate T cells, which can be restored by blockade of ILT3. Moreover, ILT3(high)ILT4(high) DCs lead to the induction of CD4(+)CD25(+) Foxp3(+) T regulatory cells with suppressive activity from CD4(+)CD25(-) T cells. The generation of ILT3(high)ILT4(high) DCs with tolerogenic properties by tryptophan deprivation is linked to a stress response pathway mediated by the GCN2 kinase. These results demonstrate that tryptophan degradation establishes a regulatory microenvironment for DCs, enabling these cells to induce T regulatory cells. The impact of IDO thus extends beyond local immune suppression to a systemic control of the immune response.

  14. 5-HT3 receptor antagonist MDL 72222 attenuates cocaine- and mazindol-, but not methylphenidate-induced neurochemical and behavioral effects in the rat.

    Science.gov (United States)

    Kankaanpää, Aino; Meririnne, Esa; Seppälä, Timo

    2002-02-01

    It has previously been demonstrated that the 5-HT(3) receptors located in the mesolimbic brain areas are able to modulate the dopaminergic effects of various abused drugs, including cocaine (COC). The present experiments investigated the role of 5-HT(3) receptors in the actions of selected monoamine uptake inhibitors. The ability of the 5-HT(3) receptor antagonist MDL 72222 (MDL; 0.1 and 1.0 mg/kg) to modify the neurochemical and behavioral changes induced by COC (20 mg/kg), mazindol (MAZ; 10 mg/kg), and methylphenidate (MP; 5.0 or 10, and 20 mg/kg) was assessed with an in vivo microdialysis technique, a conditioned place preference method, and motor activity measurements. MDL robustly attenuated the elevation of extracellular dopamine levels in the nucleus accumbens, acquisition of place preference, and motor activity induced by COC and MAZ, but not those induced by MP, the only drug with no significant effect on 5-HT. In contrast, expression of COC-induced place preference was not attenuated by MDL. These results show that COC- and MAZ-induced reward-related neurochemical and behavioral effects, preferentially those implicated in development of conditioned reward, are modified by the 5-HT(3) blockade. In contrast to COC and MAZ, the changes induced by MP, which has less effect on the serotonergic system, remain unchanged. Thus it appears that involvement of a serotonergic component in the mechanism of action of a drug could be a prerequisite for effective antagonism by 5-HT(3) receptor blockers.

  15. Histologic and inflammatory lamellar changes in horses with oligofructose-induced laminitis treated with a CXCR1/2 antagonist

    Directory of Open Access Journals (Sweden)

    Leonardo R. de Lima

    2016-01-01

    Full Text Available Abstract: With the hypothesis that blocking chemokine signaling can ameliorate acute laminitis, the aim was to evaluate the therapeutic effect of intravenous DF1681B, a selective antagonist for CXCR1 and CXCR2 (chemokine receptors, in an oligofructose equine laminitis model. To twelve mixed breed clinically healthy hoses with no previous history of hoof-related lameness was administered oligofructose (10g/kg given by nasogastric tube and divided into two groups: treated (intravenous DF1681B at 30mg/kg 6, 12, 18, and 24h after oligofructose and non-treated groups. Laminar biopsies were performed before and 12, 36, and 72h after administering oligofructose. Samples were stained with periodic acid-Schiff (PAS and scored from 0 to 6 according to epidermal cell and basal membrane changes. The IL-1β, IL-6, and CXCL1 RNA expressions were determined by RT-PCR. Parametric and non-parametric tests were used to compare times within each group (P<0.05. The PAS grades and IL-1β and IL-6 RNA expression increased in the non-treated group, but remained constant in the treated horses. In conclusion, DF1681B therapy reduced laminar inflammation and epidermal deterioration in treated horses. CXCR1/2 blockage should be considered therapeutically for equine acute laminitis.

  16. Pigment epithelium-derived factor up-regulation induced by memantine, an N-methyl-D-aspartate receptor antagonist, is involved in increased proliferation of hippocampal progenitor cells.

    Science.gov (United States)

    Namba, T; Yabe, T; Gonda, Y; Ichikawa, N; Sanagi, T; Arikawa-Hirasawa, E; Mochizuki, H; Kohsaka, S; Uchino, S

    2010-05-05

    Memantine is classified as an NMDA receptor antagonist. We recently reported that memantine promoted the proliferation of neural progenitor cells and the production of mature granule neurons in the adult hippocampus. However, the molecular mechanism responsible for the memantine-induced promotion of cellular proliferation remains unknown. In this study we searched for a factor that mediates memantine-induced cellular proliferation, and found that pigment epithelium-derived factor (PEDF), a broad-acting neurotrophic factor, is up-regulated in the dentate gyrus of adult mice after the injection of memantine. PEDF mRNA expression increased significantly by 3.5-fold at 1 day after the injection of memantine. In addition, the expression level of PEDF protein also increased by 1.8-fold at 2 days after the injection of memantine. Immunohistochemical study using anti-PEDF antibody showed that the majority of the PEDF-expressing cells were protoplasmic and perivascular astrocytes. Using a neurosphere assay, we confirmed that PEDF enhanced cellular proliferation under the presence of fibroblast growth factor-2 (FGF-2) and epidermal growth factor (EGF) but was not involved in the multilineage potency of hippocampal progenitor cells. Over expression of PEDF by adeno-associated virus, however, did not stimulate cellular proliferation, suggesting PEDF per se does not promote cellular proliferation in vivo. These findings suggest that the memantine induced PEDF up-regulation is involved in increased proliferation of hippocampal progenitor cells. (c) 2010 IBRO. Published by Elsevier Ltd. All rights reserved.

  17. Effects of Preoperative Serotonin-Receptor-Antagonist Administration in Spinal Anesthesia-Induced Hypotension: A Randomized, Double-blind Comparison Study of Ramosetron and Ondansetron.

    Science.gov (United States)

    Shin, Hyun-Jung; Choi, Eun-Su; Lee, Gwan-Woo; Do, Sang-Hwan

    2015-01-01

    The adverse effects of spinal anesthesia (SA) include arterial hypotension and bradycardia. The aim of this study was to compare the effects of 2 type 3 serotonin receptor antagonists in SA-induced adverse effects. Specifically, we assessed whether ramosetron was more effective than ondansetron in reducing SA-induced decreases in blood pressure (BP) and heart rate (HR). A total of 117 patients undergoing orthopedic surgery and receiving SA were intravenously administered 0.3 mg of ramosetron (n = 39, group R), 4 mg of ondansetron (n = 39, group O4), or 8 mg of ondansetron (n = 39, group O8). Systolic BP (SBP), diastolic BP (DBP), mean BP (MBP), HR, and the lowest SBP, DBP, MBP, and HR values were measured preoperatively (baseline) and intraoperatively. The incidence of postoperative nausea and vomiting, the need for rescue antiemetics, the amount of patient-controlled analgesia consumption, and pain score in the first 48 hours after surgery were determined. Baseline values did not significantly differ among the 3 groups. After SA, SBP, DBP, MBP, and HR were lower than their baseline values in all 3 groups. The differences between the baseline and the lowest values were significantly less in group R than in groups O4 and O8 with respect to SBP (P controlled analgesia consumption, or pain score. The administration of ramosetron (0.3 mg) significantly attenuated the SA-induced decrease in BP compared with 4 or 8 mg of ondansetron and HR compared with 4 mg of ondansetron.

  18. Transcriptome Profiling of the Virus-Induced Innate Immune Response in Pteropus vampyrus and Its Attenuation by Nipah Virus Interferon Antagonist Functions.

    Science.gov (United States)

    Glennon, Nicole B; Jabado, Omar; Lo, Michael K; Shaw, Megan L

    2015-08-01

    Bats are important reservoirs for several viruses, many of which cause lethal infections in humans but have reduced pathogenicity in bats. As the innate immune response is critical for controlling viruses, the nature of this response in bats and how it may differ from that in other mammals are of great interest. Using next-generation transcriptome sequencing (mRNA-seq), we profiled the transcriptional response of Pteropus vampyrus bat kidney (PVK) cells to Newcastle disease virus (NDV), an avian paramyxovirus known to elicit a strong innate immune response in mammalian cells. The Pteropus genus is a known reservoir of Nipah virus (NiV) and Hendra virus (HeV). Analysis of the 200 to 300 regulated genes showed that genes for interferon (IFN) and antiviral pathways are highly upregulated in NDV-infected PVK cells, including genes for beta IFN, RIG-I, MDA5, ISG15, and IRF1. NDV-infected cells also upregulated several genes not previously characterized to be antiviral, such as RND1, SERTAD1, CHAC1, and MORC3. In fact, we show that MORC3 is induced by both IFN and NDV infection in PVK cells but is not induced by either stimulus in human A549 cells. In contrast to NDV infection, HeV and NiV infection of PVK cells failed to induce these innate immune response genes. Likewise, an attenuated response was observed in PVK cells infected with recombinant NDVs expressing the NiV IFN antagonist proteins V and W. This study provides the first global profile of a robust virus-induced innate immune response in bats and indicates that henipavirus IFN antagonist mechanisms are likely active in bat cells. Bats are the reservoir host for many highly pathogenic human viruses, including henipaviruses, lyssaviruses, severe acute respiratory syndrome coronavirus, and filoviruses, and many other viruses have also been isolated from bats. Viral infections are reportedly asymptomatic or heavily attenuated in bat populations. Despite their ecological importance to viral maintenance, research

  19. Drp1 is dispensable for apoptotic cytochrome c release in primed MCF10A and fibroblast cells but affects Bcl-2 antagonist-induced respiratory changes.

    Science.gov (United States)

    Clerc, P; Ge, S X; Hwang, H; Waddell, J; Roelofs, B A; Karbowski, M; Sesaki, H; Polster, B M

    2014-04-01

    Dynamin-related protein 1 (Drp1) mediates mitochondrial fission and is thought to promote Bax/Bak-induced cytochrome c release during apoptosis. Conformationally active Bax, Bak and Bax/Bak-activating BH3-only proteins, such as Bim, are restrained by anti-apoptotic Bcl-2 proteins in cells that are 'primed for death'. Inhibition of Bcl-2/Bcl-xL/Bcl-w by the antagonist ABT-737 causes rapid apoptosis of primed cells. Hence, we determined whether Drp1 is required for cytochrome c release, respiratory alterations and apoptosis of cells that are already primed for death. We tested the Drp1 inhibitor mdivi-1 for inhibition of cytochrome c release in MCF10A cells primed by Bcl-2 overexpression. We measured ATP synthesis-dependent, -independent and cytochrome c-limited maximal oxygen consumption rates (OCRs) and cell death of immortalized wild-type (WT) and Drp1 knockout (KO) mouse embryonic fibroblasts (MEFs) treated with ABT-737. Mdivi-1 failed to attenuate ABT-737-induced cytochrome c release. ABT-737 decreased maximal OCR measured in the presence of uncoupler in both WT and Drp1 KO MEF, consistent with respiratory impairment due to release of cytochrome c. However, Drp1 KO MEF were slightly less sensitive to this ABT-737-induced respiratory inhibition compared with WT, and were resistant to an initial ABT-737-induced increase in ATP synthesis-independent O2 consumption. Nevertheless, caspase-dependent cell death was not reduced. Pro-apoptotic Bax was unaltered, whereas Bak was up-regulated in Drp1 KO MEF. The findings indicate that once fibroblast cells are primed for death, Drp1 is not required for apoptosis. However, Drp1 may contribute to ABT-737-induced respiratory changes and the kinetics of cytochrome c release. © 2013 The British Pharmacological Society.

  20. Randomised trial of the effect of a gastrin/CCK2receptor antagonist on esomeprazole-induced hypergastrinaemia: evidence against rebound hyperacidity.

    Science.gov (United States)

    Boyce, Malcolm; van den Berg, Frans; Mitchell, Toni; Darwin, Kate; Warrington, Steve

    2017-02-01

    Hypergastrinaemia induced by proton pump inhibitor (PPI) therapy may cause ECL-cell and parietal-cell hyperplasia and rebound hyperacidity and dyspepsia after PPI withdrawal. The aim of the study was to assess the effect of different dosage-regimens of netazepide, a gastrin/CCK 2 receptor antagonist, on PPI-induced hypergastrinaemia and elevated chromogranin A (CgA). Six groups of eight healthy subjects participated in a randomised, double-blind study of esomeprazole 40 mg daily for 28 days, in combination with netazepide 1, 5 or 25 mg or placebo, daily, during the last 14 days of esomeprazole or during 14 days after treatment withdrawal. Fasting serum gastrin and plasma CgA were measured during treatment and after withdrawal, as biomarkers of acid suppression and ECL-cell activity, respectively. Dyspepsia was monitored throughout the study. Esomeprazole increased gastrin and CgA. Netazepide increased gastrin, but not CgA, and inhibited dose dependently the CgA response to esomeprazole. Gastrin and CgA returned to baseline within 2-3 days of esomeprazole withdrawal; netazepide did not shorten that time. There was no rebound dyspepsia after esomeprazole withdrawal. Esomeprazole and netazepide each increase gastrin, consistent with a secondary effect of gastric acid suppression, but by different mechanisms. Esomeprazole-induced hypergastrinaemia stimulates ECL cells and thereby increases CgA. Netazepide-induced hypergastrinaemia does not increase CgA, because netazepide blocks gastrin/CCK 2 receptors on ECL cells. Co-administration of netazepide 5 mg abolishes the effect of esomeprazole-induced hypergastrinaemia on ECL cells. The quick return to baseline of gastrin and CgA and absence of dyspepsia after esomeprazole withdrawal do not support the concept of rebound hyperacidity.

  1. Evaluating the function of calcium antagonist on the Cd-induced stress in sperm of Russian sturgeon, Acipenser gueldenstaedtii

    Energy Technology Data Exchange (ETDEWEB)

    Li Zhihua, E-mail: zhihuali06@yahoo.com [University of South Bohemia in Ceske Budejovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zatisi 728/II, 389 25 Vodnany (Czech Republic); Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Jingzhou 434000 (China); Li Ping [University of South Bohemia in Ceske Budejovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zatisi 728/II, 389 25 Vodnany (Czech Republic); Yangtze River Fisheries Research Institute, Chinese Academy of Fishery Sciences, Jingzhou 434000 (China); Rodina, Marek; Randak, Tomas [University of South Bohemia in Ceske Budejovice, Faculty of Fisheries and Protection of Waters, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Zatisi 728/II, 389 25 Vodnany (Czech Republic)

    2010-11-15

    In the current study, the sperm of Russian sturgeon (Acipenser gueldenstaedtii) was used to evaluate the roles of Verapamil (VRP), a calcium channel blocker, against cadmium (Cd)-induced stress. Sturgeon sperm were exposed for 2 h at 50 {mu}g/L VRP, 5.0 {mu}g/L Cd, the mixture of 50 {mu}g/L VRP + 5.0 {mu}g/L Cd, 50 {mu}g/L Cd and the mixture of 50 {mu}g/L VRP + 50 {mu}g/L Cd. After exposure, the sperm motility parameters (motility and velocity), oxidative stress levels (lipid peroxidation [LPO] and carbonyl protein [CP]) and antioxidant enzyme activities (superoxide dismutase [SOD], glutathione reductase [GR], glutathione peroxidase [GPx]) were measured in sturgeon sperm. Compared to the control, Cd-induced stress was apparent as reflected by depressed motility parameters, induced oxidative stress and inhibited antioxidant enzyme activities at both Cd concentrations. In the presence of VRP, Cd-induced stress was reduced in sturgeon sperm, especially all the measured parameters in the sperm exposed at 5.0 {mu}g/L Cd returned to control levels, expect for the sperm motility. The present results indicate that VRP can reduce the Cd-induced stress in sturgeon sperm and suggest that using of sperm in vitro assays may provide a novel and efficient means for evaluating the effects of residual metals in the aquatic environment of sturgeon.

  2. Effect of the Toll-Like Receptor 4 Antagonist Eritoran on Retinochoroidal Inflammatory Damage in a Rat Model of Endotoxin-Induced Inflammation

    Directory of Open Access Journals (Sweden)

    Feyzahan Ekici

    2014-01-01

    Full Text Available Purpose. We investigated the effect of eritoran, a Toll-like receptor 4 antagonist, on retinochoroidal inflammatory damage in an endotoxin-induced inflammatory rat model. Methods. Endotoxin-induced inflammatory model was obtained by intraperitoneal injection of 1.5 mg/kg lipopolysaccharide (LPS. Group 1 had control rats; in groups 2-3 LPS and 0.5 mg/kg sterile saline were injected; and in groups 4-5 LPS and 0.5 mg/kg eritoran were injected. Blood samples were taken and eyes were enucleated after 12 hours (h (groups 2 and 4 or 24 hours (Groups 3 and 5. Tumor necrosis factor-α (TNF-α and malondialdehyde (MDA levels in the serum and retinochoroidal tissue and nuclear factor kappa-B (NFκB levels in retinochoroidal tissue were determined. Histopathological examination was performed and retinochoroidal changes were scored. Results. Eritoran treatment resulted in lower levels of TNF-α, MDA, and NFκB after 12 h which became significant after 24 h. Serum TNF-α and retinochoroidal tissue NFκB levels were similar to control animals at the 24th h of the study. Eritoran significantly reversed histopathological damage after 24 h. Conclusions. Eritoran treatment resulted in less inflammatory damage in terms of serum and retinochoroidal tissue parameters.

  3. Role of neurokinin 1 receptors in dextran sulfate-induced colitis: studies with gene-deleted mice and the selective receptor antagonist netupitant.

    Science.gov (United States)

    Szitter, István; Pintér, Erika; Perkecz, Anikó; Kemény, Agnes; Kun, József; Kereskai, László; Pietra, Claudio; Quinn, John P; Zimmer, Andreas; Berger, Alexandra; Paige, Christopher J; Helyes, Zsuzsanna

    2014-05-01

    The function of the neurokinin 1 (NK1) receptor was investigated in the DSS-induced mouse colitis model using NK1 receptor-deficient mice and the selective antagonist netupitant. Colitis was induced by oral administration of 20 mg/ml DSS solution for 7 days in C57BL/6 and Tacr1 KO animals (n = 5-7). During the induction, one-half of the C57BL/6 and Tacr1 KO group received one daily dose of 6 mg/kg netupitant, administered intraperitoneally, the other half of the group received saline, respectively. Disease activity index (DAI), on the basis of stool consistency, blood and weight loss, was determined over 7 days. Histological evaluation, myeloperoxidase (MPO) measurement, cytokine concentrations and receptor expression analysis were performed on the colon samples. NK1 receptors are up-regulated in the colon in response to DSS treatment. DSS increased DAI, histopathological scores, BLC, sICAM-1, IFN-γ, IL-16 and JE in wildtype mice, which were significantly reduced in NK1 receptor-deficient ones. NK1 receptor antagonism with netupitant significantly diminished DAI, inflammatory histopathological alterations, BLC, IFN-γ, IL-13 and IL-16 in wildtype mice, but not in the NK1-deficient ones. MPO was similarly elevated and netupitant significantly decreased its activity in both groups. NK1 receptor antagonism could be beneficial for colitis via inhibiting different inflammatory mechanisms.

  4. NMDA antagonist, but not nNOS inhibitor, requires AMPA receptors in the ventromedial prefrontal cortex (vmPFC) to induce antidepressant-like effects

    DEFF Research Database (Denmark)

    Pereira, V. S.; Wegener, Gregers; Joca, S. R.

    2013-01-01

    Depressed individuals and stressed animals show enhanced levels of glutamate and neuronal nitric oxide synthase (nNOS) activity in limbic structures, including the vmPFC. Systemic administration of glutamatergic NMDA receptor antagonists or inhibitors of nitric oxide (NO) synthesis induces...... of the glutamatergic and nitrergic systems of the vmPFC on the behavioral consequences induced by forced swimming (FS), an animal model of depression. Male Wistar rats (230-260g) with guide cannulas aimed at the prelimbic (PL) region of vmPFC were submitted to a 15min session of FS and, 24h later, they were submitted...... administration into vmPFC-PL reduced the IT (Mean(plus or minus)SEM: vehicle: 116.3(plus or minus)21.17; LY 1nmol: 164.4(plus or minus)18.92; LY 3nmol: 28.71(plus or minus)10.21null; LY 10nmol: 39.43(plus or minus)7.99null; nullp...

  5. The glucocorticoid antagonist mifepristone attenuates sound-induced long-term deficits in auditory nerve response and central auditory processing in female rats.

    Science.gov (United States)

    Singer, Wibke; Kasini, Kamyar; Manthey, Marie; Eckert, Philipp; Armbruster, Philipp; Vogt, Miriam Annika; Jaumann, Mirko; Dotta, Michela; Yamahara, Kohei; Harasztosi, Csaba; Zimmermann, Ulrike; Knipper, Marlies; Rüttiger, Lukas

    2018-01-12

    Systemic corticosteroids have been the mainstay of treatment for various hearing disorders for more than 30 yr. Accordingly, numerous studies have described glucocorticoids (GCs) and stressors to be protective in the auditory organ against damage associated with a variety of health conditions, including noise exposure. Conversely, stressors are also predictive risk factors for hearing disorders. How both of these contrasting stress actions are linked has remained elusive. Here, we demonstrate that higher corticosterone levels during acoustic trauma in female rats is highly correlated with a decline of auditory fiber responses in high-frequency cochlear regions, and that hearing thresholds and the outer hair cell functions (distortion products of otoacoustic emissions) are left unaffected. Moreover, when GC receptor (GR) or mineralocorticoid receptor (MR) activation was antagonized by mifepristone or spironolactone, respectively, GR, but not MR, inhibition significantly and permanently attenuated trauma-induced effects on auditory fiber responses, including inner hair cell ribbon loss and related reductions of early and late auditory brainstem responses. These findings strongly imply that higher corticosterone stress levels profoundly impair auditory nerve processing, which may influence central auditory acuity. These changes are likely GR mediated as they are prevented by mifepristone.-Singer, W., Kasini, K., Manthey, M., Eckert, P., Armbruster, P., Vogt, M. A., Jaumann, M., Dotta, M., Yamahara, K., Harasztosi, C., Zimmermann, U., Knipper, M., Rüttiger, L. The glucocorticoid antagonist mifepristone attenuates sound-induced long-term deficits in auditory nerve response and central auditory processing in female rats.

  6. Controlled Release of Interleukin-1 Receptor Antagonist from Hyaluronic Acid-Chitosan Microspheres Attenuates Interleukin-1β-Induced Inflammation and Apoptosis in Chondrocytes

    Directory of Open Access Journals (Sweden)

    Bo Qiu

    2016-01-01

    Full Text Available This paper investigates the protective effect of interleukin-1 receptor antagonist (IL-1Ra released from hyaluronic acid chitosan (HA-CS microspheres in a controlled manner on IL-1β-induced inflammation and apoptosis in chondrocytes. The IL-1Ra release kinetics was characterized by an initial burst release, which was reduced to a linear release over eight days. Chondrocytes were stimulated with 10 ng/ml IL-1β and subsequently incubated with HA-CS-IL-1Ra microspheres. The cell viability was decreased by IL-1β, which was attenuated by HA-CS-IL-1Ra microspheres as indicated by an MTT assay. ELISA showed that HA-CS-IL-1Ra microspheres inhibited IL-1β-induced inflammation by attenuating increases in NO2- and prostaglandin E2 levels as well as increase in glycosaminoglycan release. A terminal deoxyribonucleotide transferase deoxyuridine triphosphate nick-end labeling assay revealed that the IL-1β-induced chondrocyte apoptosis was decreased by HA-CS-IL-1Ra microspheres. Moreover, HA-CS-IL-1Ra microspheres blocked IL-1β-induced chondrocyte apoptosis by increasing B-cell lymphoma 2 (Bcl-2 and decreasing Bcl-2-associated X protein and caspase-3 expressions at mRNA and protein levels, as indicated by reverse-transcription quantitative polymerase chain reaction and western blot analysis, respectively. The results of the present study indicated that HA-CS-IL-1Ra microspheres as a controlled release system of IL-1Ra possess potential anti-inflammatory and antiapoptotic properties in rat chondrocytes due to their ability to regulate inflammatory factors and apoptosis associated genes.

  7. Orexin receptor antagonist-induced sleep does not impair the ability to wake in response to emotionally salient acoustic stimuli in dogs

    Directory of Open Access Journals (Sweden)

    Pamela L. Tannenbaum

    2014-05-01

    Full Text Available The ability to awaken from sleep in response to important stimuli is a critical feature of normal sleep, as is maintaining sleep continuity in the presence of irrelevant background noise. Dual orexin receptor antagonists (DORAs effectively promote sleep across species by targeting the evolutionarily conserved wake-promoting orexin signaling pathway. This study in dogs investigated whether DORA-induced sleep preserved the ability to awaken appropriately to salient acoustic stimuli but remain asleep when exposed to irrelevant stimuli. Sleep and wake in response to DORAs, vehicle, GABA-A receptor modulators (diazepam, eszopiclone and zolpidem and antihistamine (diphenhydramine administration were evaluated in telemetry-implanted adult dogs with continuous electrocorticogram, electromyogram, electrooculogram, and activity recordings. DORAs induced sleep, but GABA-A modulators and antihistamine induced paradoxical hyperarousal. Thus, salience gating studies were conducted during DORA-22 (0.3, 1, and 5 mg/kg; day and night and vehicle nighttime sleep. The acoustic stimuli were either classically conditioned using food reward and positive attention (salient stimulus or presented randomly (neutral stimulus. Once conditioned, the tones were presented at sleep times corresponding to maximal DORA-22 exposure. In response to the salient stimuli, dogs woke completely from vehicle and orexin-antagonized sleep across all sleep stages but rarely awoke to neutral stimuli. Notably, acute pharmacological antagonism of orexin receptors paired with emotionally salient anticipation produced wake, not cataplexy, in a species where genetic (chronic loss of orexin receptor signaling leads to narcolepsy/cataplexy. DORA-induced sleep in this species thereby retains the desired capacity to awaken to emotionally salient acoustic stimuli while preserving uninterrupted sleep in response to irrelevant stimuli.

  8. The anti-inflammatory effect of montelukast, a cysteinyl leukotriene receptor-1 antagonist, against estradiol-induced nonbacterial inflammation in the rat prostate.

    Science.gov (United States)

    Said, Mahmoud M; Bosland, Maarten C

    2017-02-01

    There is no standard treatment of chronic nonbacterial prostatitis in humans. The current study was aimed to investigate the effect of montelukast, an antagonist of cysteinyl leukotriene receptor-1, against estrogen-induced, nonbacterial lateral lobe-specific prostate inflammation in rats. Male Wistar rats were randomized into five groups of six rats, including sham controls (group 1) and castrated rats (group 2), whereas nonbacterial prostatitis (NBP) was induced in groups 3-5 by castration followed by a daily subcutaneous injection of estradiol (0.25 mg/kg body weight) for 30 days. The rats were left otherwise untreated (group 3) or received a daily oral administration of montelukast (1 and 10 mg/kg body weight for groups 4 and 5, respectively) from the 17th day after castration for two consecutive weeks. Compared with sham controls, induction of NBP led to a significant increase in serum leukotriene B 4 (LTB4), tumor necrosis factor alpha (TNF-α), and interleukin 6 (IL-6) levels, along with a significant upregulation in the transcript level of proinflammatory molecules (nuclear factor kappa beta [NF-κβ] and inducible nitric oxide synthase [iNOS]), chemokines (monocyte chemoattractant protein-1 [MCP-1] and eotaxin), and E-selectin in the lateral prostate. Histological examination revealed intense inflammation in the prostate with leukocyte infiltration and acinar degeneration following estradiol treatment of castrated rats. Montelukast significantly suppressed the increase in serum and prostate proinflammatory mediators/chemokines expression and abolished the histologically inflammatory changes in the lateral prostate. These findings indicate that montelukast inhibits estradiol-induced NBP in a rat model through anti-inflammatory mechanisms, suggesting its future beneficial effect for the treatment of clinical chronic NBP.

  9. Antinociceptive synergistic effect of spinal mGluR2/3 antagonist and glial cells inhibitor on peripheral inflammation-induced mechanical hypersensitivity.

    Science.gov (United States)

    Zhang, Ting; Zhang, Jing; Shi, Juan; Feng, Yupeng; Sun, Zhong Sheng; Li, Huili

    2009-05-29

    Metabotropic glutamate receptor (mGluR) 2/3 is distributed in neurons and glial cells in many regions of the nervous system, but its role in nociceptive processing is unclear. In this study, we examined the mRNA expressions of mGluR2 and mGluR3, by real-time RT-PCR, in the spinal cord. We further investigated the possible involvement of mGluR2/3 and mechanisms underlying peripheral inflammatory pain induced by subcutaneous complete Freund's adjuvant (CFA) injection. We demonstrate that compared to the controls, the mRNA expression levels of mGluR2 and mGluR3 were significantly higher 4h after CFA injection. Functionally, blocking mGluR2/3 by their antagonist (2S)-2-amino-2-[(1S, 2S)-2-carboxycycloprop-1-yl]-3-(xanth-9-yl) propanoic acid (LY341495) alleviated the CFA-induced mechanical allodynia and the inhibitory effects were reversed by mGluR2/3 agonist (2R, 4R)-4-aminopyrrolidine-2,4-dicarboxylate ((2R, 4R)-APDC). In addition, a glial metabolism inhibitor dl-fluorocitric acid barium salt (fluorocitric acid) also inhibited the CFA-induced mechanical allodynia in a dose-dependent manner. Remarkably, simultaneous inhibition of mGluR2/3 and glial metabolism had synergistic effects. The co-administration of LY341495 and fluorocitric acid with minimal dosages produced significant more inhibition than the additive effects by the individual inhibitor alone. In summary, our data suggest that spinal mGluR2/3 contributes to the generation of mechanical allodynia induced by peripheral inflammation. We also suggest that involvement of mGluR2/3 in the communication between glial cells and neurons takes part in the processing of nociceptive information.

  10. Effect of histamine H1 receptor antagonists on TARC/CCL17 and MDC/CCL22 production from CD14+ cells induced by antigenic stimulation in vitro.

    Science.gov (United States)

    Shoji, Naruo; Asano, Kazuhito; Furuta, Atsuko; Hirano, Kojiro; Suzaki, Harumi

    2011-01-01

    Thymus- and activation-regulated chemokine (TARC) and macrophage-derived chemokine (MDC) are accepted to be important molecules in the development and maintenance of allergic diseases. Although several types of histamine H(1) receptor antagonist (antihistamine) have been developed and used for the treatment of allergic diseases, the influence of antihistamines on TARC and MDC production is not well understood. The present study was undertaken to examine the influence of antihistamines on TARC and MDC production from CD14+ cells after antigenic stimulation in vitro. CD14+ cells prepared from patients with pollinosis to Japanese cedar pollen were stimulated with specific allergen extracted from Japanese cedar pollen (Cry j 1) in the presence of azelastine (AZE), ketotifen (KET), fexofenadine (FEX) and oxatomide (OXA) for 6 days. TARC and MDC levels in culture supernatants were examined by ELISA. We also examined the influence of FEX on TARC and MDC mRNA expression, phosphorylation of mitogen-activated protein kinases (MAPKs) and transcription factor activation in CD14+ cells after Cry j 1 stimulation. FEX at 250 ng/ml, which is almost equal to therapeutic blood levels, caused a significant inhibition of TARC and MDC production.However, AZE, OXA and KET required higher concentrations than their therapeutic blood levels to suppress production of these factors. FEX at 250 ng/ml also suppressed NF-κB activation, phosphorylation of p38 MAPK and extracellular signal-regulated kinases 1 and 2 and expression of mRNA for TARC and MDC. These results suggest that antihistamines, especially FEX, suppress CC chemokine production from CD14+ cells through interference with antigen-mediated signaling and result in favorable modification of allergic disease states or conditions. Copyright © 2010 S. Karger AG, Basel.

  11. The kappa-opioid receptor antagonist nor-BNI inhibits cocaine and amphetamine, but not cannabinoid (WIN 52212-2), abstinence-induced withdrawal in planarians: an instance of 'pharmacologic congruence'.

    Science.gov (United States)

    Raffa, Robert B; Stagliano, Gregory W; Ross, Geoffrey; Powell, Jenay A; Phillips, Austin G; Ding, Zhe; Rawls, Scott M

    2008-02-08

    The broad applicability of receptor theory to diverse species, from invertebrates to mammals, provides evidence for the evolution in complexity of pharmacologic receptor diversification and of receptor-effector signal transduction mechanisms. However, pre-mammalian species have less receptor subtype differentiation, and thus, might share signal transduction pathways to a greater extent than do mammals, a phenomenon that we term 'pharmacologic congruence'. We have demonstrated previously that the lowest species considered to have a centralized nervous system, planarians, display both abstinence-induced and antagonist-precipitated withdrawal signs, indicative of the development of physical dependence. We report here: (1) amphetamine abstinence-induced withdrawal, and (2) the attenuation of cocaine and amphetamine, but not cannabinoid agonist (WIN 52212-2), abstinence-induced withdrawal by the opioid receptor antagonist naloxone and by the selective kappa-opioid receptor subtype antagonist nor-BNI (nor-Binaltorphimine), but not by the selective mu-opioid or the delta-opioid receptor subtype antagonists CTAP (D-Phe-Cys-Tyr-D-Trp-Arg-Thr-Pen-Thr-NH(2)) and naltrindole. These results provide evidence that the withdrawal from cocaine and amphetamine, but not cannabinoids, in planarians is mediated through a common nor-BNI-sensitive (kappa-opioid receptor-like) pathway.

  12. Prophylaxis of Radiation-Induced Nausea and Vomiting Using 5-Hydroxytryptamine-3 Serotonin Receptor Antagonists: A Systematic Review of Randomized Trials

    Energy Technology Data Exchange (ETDEWEB)

    Salvo, Nadia; Doble, Brett [Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario (Canada); Khan, Luluel [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Amirthevasar, Gayathri [Department of Clinical Epidemiology and Biostatistics, McMaster University, Hamilton, Ontario (Canada); Dennis, Kristopher [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Pasetka, Mark; DeAngelis, Carlo [Department of Oncology Pharmacy, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Tsao, May [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada); Chow, Edward, E-mail: Edward.Chow@sunnybrook.ca [Department of Radiation Oncology, Odette Cancer Centre, Sunnybrook Health Sciences Centre, University of Toronto, Toronto, Ontario (Canada)

    2012-01-01

    Purpose: To systematically review the effectiveness and safety of 5-hydroxytryptamine-3 receptor antagonists (5-HT3 RAs) compared with other antiemetic medication or placebo for prophylaxis of radiation-induced nausea and vomiting. Methods and Materials: We searched the following electronic databases: MEDLINE, Embase, the Cochrane Central Register of Controlled Clinical Trials, and Web of Science. We also hand-searched reference lists of included studies. Randomized, controlled trials that compared a 5-HT3 RA with another antiemetic medication or placebo for preventing radiation-induced nausea and vomiting were included. We excluded studies recruiting patients receiving concomitant chemotherapy. When appropriate, meta-analysis was conducted using Review Manager (v5) software. Relative risks were calculated using inverse variance as the statistical method under a random-effects model. We assessed the quality of evidence by outcome using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results: Eligibility screening of 47 articles resulted in 9 included in the review. The overall methodologic quality was moderate. Meta-analysis of 5-HT3 RAs vs. placebo showed significant benefit for 5-HT3 RAs (relative risk [RR] 0.70; 95% confidence interval [CI] 0.57-0.86 for emesis; RR 0.84, 95% CI 0.73-0.96 for nausea). Meta-analysis comparing 5-HT3 RAs vs. metoclopramide showed a significant benefit of the 5-HT3 RAs for emetic control (RR 0.27, 95% CI 0.15-0.47). Conclusion: 5-Hydroxytryptamine-3 RAs are superior to placebo and other antiemetics for prevention of emesis, but little benefit was identified for nausea prevention. 5-Hydroxytryptamine-3 RAs are suggested for prevention of emesis. Limited evidence was found regarding delayed emesis, adverse events, quality of life, or need for rescue medication. Future randomized, controlled trials should evaluate different 5-HT3 antiemetics and new agents with novel mechanisms of action such at the NK

  13. Prophylaxis of Radiation-Induced Nausea and Vomiting Using 5-Hydroxytryptamine-3 Serotonin Receptor Antagonists: A Systematic Review of Randomized Trials

    International Nuclear Information System (INIS)

    Salvo, Nadia; Doble, Brett; Khan, Luluel; Amirthevasar, Gayathri; Dennis, Kristopher; Pasetka, Mark; DeAngelis, Carlo; Tsao, May; Chow, Edward

    2012-01-01

    Purpose: To systematically review the effectiveness and safety of 5-hydroxytryptamine-3 receptor antagonists (5-HT3 RAs) compared with other antiemetic medication or placebo for prophylaxis of radiation-induced nausea and vomiting. Methods and Materials: We searched the following electronic databases: MEDLINE, Embase, the Cochrane Central Register of Controlled Clinical Trials, and Web of Science. We also hand-searched reference lists of included studies. Randomized, controlled trials that compared a 5-HT3 RA with another antiemetic medication or placebo for preventing radiation-induced nausea and vomiting were included. We excluded studies recruiting patients receiving concomitant chemotherapy. When appropriate, meta-analysis was conducted using Review Manager (v5) software. Relative risks were calculated using inverse variance as the statistical method under a random-effects model. We assessed the quality of evidence by outcome using the Grading of Recommendations Assessment, Development, and Evaluation approach. Results: Eligibility screening of 47 articles resulted in 9 included in the review. The overall methodologic quality was moderate. Meta-analysis of 5-HT3 RAs vs. placebo showed significant benefit for 5-HT3 RAs (relative risk [RR] 0.70; 95% confidence interval [CI] 0.57–0.86 for emesis; RR 0.84, 95% CI 0.73–0.96 for nausea). Meta-analysis comparing 5-HT3 RAs vs. metoclopramide showed a significant benefit of the 5-HT3 RAs for emetic control (RR 0.27, 95% CI 0.15–0.47). Conclusion: 5-Hydroxytryptamine-3 RAs are superior to placebo and other antiemetics for prevention of emesis, but little benefit was identified for nausea prevention. 5-Hydroxytryptamine-3 RAs are suggested for prevention of emesis. Limited evidence was found regarding delayed emesis, adverse events, quality of life, or need for rescue medication. Future randomized, controlled trials should evaluate different 5-HT3 antiemetics and new agents with novel mechanisms of action such at

  14. NETUPITANT, A POTENT AND HIGHLY SELECTIVE NK1 RECEPTOR ANTAGONIST, ALLEVIATES ACETIC ACID-INDUCED BLADDER OVERACTIVITY IN ANESTHETIZED GUINEA-PIGS

    Directory of Open Access Journals (Sweden)

    Stefano Palea

    2016-08-01

    Full Text Available Introduction. Tachykinins potently contract the isolated urinary bladder from a number of animal species and play an important role in the regulation of the micturition reflex. On the guinea-pig isolated urinary bladder we examined the effects of a new potent and selective NK1 receptor antagonist (netupitant on the contractions induced by a selective NK1 receptor agonist, SP-methylester (SP-OMe. Moreover, the effects of netupitant and another selective NK1 antagonist (L-733,060 were studied in anesthetized guinea-pigs using two experimental models, the isovolumetric bladder contractions and a model of bladder overactivity induced by intravesical administration of acetic acid (AA. Methods and Results. Detrusor muscle strips were mounted in 5 mL organ baths and isometric contractions to cumulative concentrations of SP-OME were recorded before and after incubation with increasing concentrations of netupitant. In anesthetized female guinea-pigs, reflex bladder activity was examined under isovolumetric conditions with the bladder distended with saline or during cystometry using intravesical infusion of acetic acid (AA. After a 30 min stabilization period, netupitant (0.1-3 mg/kg, i.v. or L-733,060 (3-10 mg/kg, i.v. were administered. In the detrusor muscle, netupitant produced a concentration-dependent inhibition (mean pKB = 9.24 of the responses to SP-OMe. Under isovolumetric conditions, netupitant or L-733,060 reduced bladder contraction frequency in a dose-dependent manner, but neither drug changed bladder contraction amplitude. In the AA model, netupitant dose-dependently increased intercontraction interval (ICI but had no effect on the amplitude of micturition (AM. L-733,060 dose-dependently increased ICI also but this effect was paralleled by a significant reduction of AM. Conclusion. Netupitant decreases the frequency of reflex bladder contractions without altering their amplitude, suggesting that this drug targets the afferent limb of the

  15. Netupitant, a Potent and Highly Selective NK1 Receptor Antagonist, Alleviates Acetic Acid-Induced Bladder Overactivity in Anesthetized Guinea-Pigs.

    Science.gov (United States)

    Palea, Stefano; Guilloteau, Véronique; Rekik, Moéz; Lovati, Emanuela; Guerard, Marc; Guardia, Maria-Alba; Lluel, Philippe; Pietra, Claudio; Yoshiyama, Mitsuharu

    2016-01-01

    Introduction. Tachykinins potently contract the isolated urinary bladder from a number of animal species and play an important role in the regulation of the micturition reflex. On the guinea-pig isolated urinary bladder we examined the effects of a new potent and selective NK1 receptor antagonist (netupitant) on the contractions induced by a selective NK1 receptor agonist, SP-methylester (SP-OMe). Moreover, the effects of netupitant and another selective NK1 antagonist (L-733,060) were studied in anesthetized guinea-pigs using two experimental models, the isovolumetric bladder contractions and a model of bladder overactivity induced by intravesical administration of acetic acid (AA). Methods and Results. Detrusor muscle strips were mounted in 5 mL organ baths and isometric contractions to cumulative concentrations of SP-OME were recorded before and after incubation with increasing concentrations of netupitant. In anesthetized female guinea-pigs, reflex bladder activity was examined under isovolumetric conditions with the bladder distended with saline or during cystometry using intravesical infusion of AA. After a 30 min stabilization period, netupitant (0.1-3 mg/kg, i.v.) or L-733,060 (3-10 mg/kg, i.v.) were administered. In the detrusor muscle, netupitant produced a concentration-dependent inhibition (mean pKB = 9.24) of the responses to SP-OMe. Under isovolumetric conditions, netupitant or L-733,060 reduced bladder contraction frequency in a dose-dependent manner, but neither drug changed bladder contraction amplitude. In the AA model, netupitant dose-dependently increased intercontraction interval (ICI) but had no effect on the amplitude of micturition (AM). L-733,060 dose-dependently increased ICI also but this effect was paralleled by a significant reduction of AM. Conclusion. Netupitant decreases the frequency of reflex bladder contractions without altering their amplitude, suggesting that this drug targets the afferent limb of the micturition reflex circuit

  16. Swertisin, a C-glucosylflavone, ameliorates scopolamine-induced memory impairment in mice with its adenosine A1 receptor antagonistic property.

    Science.gov (United States)

    Lee, Hyung Eun; Jeon, Se Jin; Ryu, Byeol; Park, Se Jin; Ko, Sang Yoon; Lee, Younghwan; Kim, Eunji; Lee, Sunhee; Kim, Haneul; Jang, Dae Sik; Ryu, Jong Hoon

    2016-06-01

    Swertisin, a C-glucosylflavone isolated from Swertia japonica, has been known to have anti-inflammatory or antidiabetic activities. Until yet, however, its cognitive function is not investigated. In the present study, we endeavored to elucidate the effects of swertisin on cholinergic blockade-induced memory impairment. Swertisin (5 or 10mg/kg, p.o.) significantly ameliorated scopolamine-induced cognitive impairment in the several behavioral tasks. Also, single administration of swertisin (10mg/kg, p.o.) in normal naïve mice enhanced the latency time in the passive avoidance task. In addition, the ameliorating effect of swertisin on scopolamine-induced memory impairment was significantly antagonized by a sub-effective dose of N6-cyclopentyladenosine (CPA, 0.1mg/kg, i.p). The adenosine A1 receptor antagonistic property of swertisin was confirmed by receptor binding assay. Furthermore, the administration of swertisin significantly increased the phosphorylation levels of hippocampal or cortical protein kinase A (PKA, 5 or 10mg/kg) and CREB (10mg/kg), and co-administration of CPA (0.1mg/kg, i.p) blocked the increased phosphorylated levels of PKA and CREB in the both cortex and hippocampus. Taken together, these results indicate that the memory-ameliorating effects of swertisin may be, in part, mediated through the adenosinergic neurotransmitter system, and that swertisin may be useful for the treatment of cognitive dysfunction observed in several diseases such as Alzheimer's disease. Copyright © 2016 Elsevier B.V. All rights reserved.

  17. The selective dopamine D3 receptor antagonist, SR 21502, reduces cue-induced reinstatement of heroin seeking and heroin conditioned place preference in rats.

    Science.gov (United States)

    Galaj, Ewa; Manuszak, Monica; Babic, Sandra; Ananthan, Subramaniam; Ranaldi, Robert

    2015-11-01

    Because the role of dopamine (DA) D3 receptors has been investigated primarily in relation to cocaine-related behaviors little is known of the role of these receptors in heroin seeking. To investigate the effect of the selective DA D3 receptor antagonist, SR 21502, on cue-induced reinstatement of heroin seeking and heroin conditioned place preference (CPP). In experiment 1, rats were trained to self-administer intravenous heroin for 15 days followed by extinction. Following extinction animals were treated with one of several SR 21502 doses (0, 7.5, 10 or 15mg/kg) and a cue-induced reinstatement test was conducted. In experiment 2, animals were conditioned to experience heroin in one compartment of a CPP apparatus and saline in the other. On the test day animals were treated with 0, 3.75, 7.5, 10 or 15mg/kg of SR 21502 and tested for their CPP. The results from experiment 1 showed a significant dose-related reduction in cue-induced reinstatement of active lever pressing in the 7.5 and 10mg groups and an absence of the reinstatement effect in the 15mg group. In experiment 2, animals treated with vehicle or 3.75mg of SR 21502 showed significant heroin place preferences but those treated with the higher doses showed no CPP. Our findings suggest that DA D3 receptors play a significant role in heroin approach behaviors driven by conditioned stimuli. As such, we propose that SR 21502 holds potential as an effective pharmacotherapeutic agent for relapse prevention and should be studied further. Copyright © 2015 Elsevier Ireland Ltd. All rights reserved.

  18. Acid-induced sweetness of neoculin is ascribed to its pH-dependent agonistic-antagonistic interaction with human sweet taste receptor.

    Science.gov (United States)

    Nakajima, Ken-ichiro; Morita, Yuji; Koizumi, Ayako; Asakura, Tomiko; Terada, Tohru; Ito, Keisuke; Shimizu-Ibuka, Akiko; Maruyama, Jun-ichi; Kitamoto, Katsuhiko; Misaka, Takumi; Abe, Keiko

    2008-07-01

    Neoculin (NCL) is a sweet protein that also has taste-modifying activity to convert sourness to sweetness. However, it has been unclear how NCL induces this unique sensation. Here we quantitatively evaluated the pH-dependent acid-induced sweetness of NCL using a cell-based assay system. The human sweet taste receptor, hT1R2-hT1R3, was functionally expressed in HEK293T cells together with G alpha protein. When NCL was applied to the cells under different pH conditions, it activated hT1R2-hT1R3 in a pH-dependent manner as the condition changed from pH 8 to 5. The pH-response sigmoidal curve resembled the imidazole titration curve, suggesting that His residues were involved in the taste-modifying activity. We then constructed an NCL variant in which all His residues were replaced with Ala and found that the variant elicited strong sweetness at neutral pH as well as at acidic pH. Since NCL and the variant elicited weak and strong sweetness at the same neutral pH, respectively, we applied different proportions of NCL-variant mixtures to the cells at this pH. As a result, NCL competitively inhibits the variant-induced receptor activation. All these data suggest that NCL acts as an hT1R2-hT1R3 agonist at acidic pH but functionally changes into its antagonist at neutral pH.

  19. The EP4 receptor antagonist, L-161,982, blocks prostaglandin E2-induced signal transduction and cell proliferation in HCA-7 colon cancer cells

    International Nuclear Information System (INIS)

    Cherukuri, Durga Prasad; Chen, Xiao B.O.; Goulet, Anne-Christine; Young, Robert N.; Han, Yongxin; Heimark, Ronald L.; Regan, John W.; Meuillet, Emmanuelle; Nelson, Mark A.

    2007-01-01

    Accumulating evidence indicates that elevated levels of prostaglandin E 2 (PGE 2 ) can increase intestinal epithelial cell proliferation, and thus play a role in colorectal tumorigenesis. PGE 2 exerts its effects through four G-protein-coupled PGE receptor (EP) subtypes, named the EP1, EP2, EP3, and EP4. Increased phosphorylation of extracellular regulated kinases (ERK1/2) is required for PGE 2 to stimulate cell proliferation of human colon cancer cells. However, the EP receptor(s) that are involved in this process remain unknown. We provide evidence that L-161,982, a selective EP4 receptor antagonist, completely blocks PGE 2 -induced ERK phosphorylation and cell proliferation of HCA-7 cells. In order to identify downstream target genes of ERK1/2 signaling, we found that PGE 2 induces expression of early growth response gene-1 (EGR-1) downstream of ERK1/2 and regulates its expression at the level of transcription. PGE 2 treatment induces phosphorylation of cyclic AMP response element binding protein (CREB) at Ser133 residue and CRE-mediated luciferase activity in HCA-7 cells. Studies with dominant-negative CREB mutant (ACREB) provide clear evidence for the involvement of CREB in PGE 2 driven egr-1 transcription in HCA-7 cells. In conclusion, this study reveals that egr-1 is a target gene of PGE 2 in HCA-7 cells and is regulated via the newly identified EP4/ERK/CREB pathway. Finally our results support the notion that antagonizing EP4 receptors may provide a novel therapeutic approach to the treatment of colon cancer

  20. The AT1 Receptor Antagonist, L-158,809, Prevents or Ameliorates Fractionated Whole-Brain Irradiation-Induced Cognitive Impairment

    International Nuclear Information System (INIS)

    Robbins, Mike E.; Payne, Valerie B.S.; Tommasi, Ellen B.S.; Diz, Debra I.; Hsu, Fang-Chi; Brown, William R.; Wheeler, Kenneth T.; Olson, John; Zhao Weiling

    2009-01-01

    Purpose: We hypothesized that administration of the angiotensin type 1 (AT1) receptor antagonist, L-158,809, to young adult male rats would prevent or ameliorate fractionated whole-brain irradiation (WBI)-induced cognitive impairment. Materials and Methods: Groups of 80 young adult male Fischer 344 x Brown Norway (F344xBN) rats, 12-14 weeks old, received either: (1) fractionated WBI; 40 Gy of γ rays in 4 weeks, 2 fractions/week, (2) sham-irradiation; (3) WBI plus L-158,809 (20 mg/L drinking water) starting 3 days prior, during, and for 14, 28, or 54 weeks postirradiation; and (4) sham-irradiation plus L-158,809 for 14, 28, or 54 weeks postirradiation. An additional group of rats (n = 20) received L-158,809 before, during, and for 5 weeks postirradiation, after which they received normal drinking water up to 28 weeks postirradiation. Results: Administration of L-158,809 before, during, and for 28 or 54 weeks after fractionated WBI prevented or ameliorated the radiation-induced cognitive impairment observed 26 and 52 weeks postirradiation. Moreover, giving L-158,809 before, during, and for only 5 weeks postirradiation ameliorated the significant cognitive impairment observed 26 weeks postirradiation. These radiation-induced cognitive impairments occurred without any changes in brain metabolites or gross histologic changes assessed at 28 and 54 weeks postirradiation, respectively. Conclusions: Administering L-158,809 before, during, and after fractionated WBI can prevent or ameliorate the chronic, progressive, cognitive impairment observed in rats at 26 and 52 weeks postirradiation. These findings offer the promise of improving the quality of life for brain tumor patients

  1. Comparison and Analysis of Delirium Induced by Histamine H2 Receptor Antagonists and Proton Pump Inhibitors in Cancer Patients

    Directory of Open Access Journals (Sweden)

    Shiro Fujii

    2012-07-01

    Full Text Available Objective: H2 blockers have been reported to be responsible for drug-induced delirium. We compared the incidence of delirium between two groups of patients who were treated with H2 blockers (H2 group or proton pump inhibitors (PPI group for anastomotic ulcer prevention following surgical treatment of esophageal cancer. Method: The incidence and severity of delirium were retrospectively compared in patients of the H2 group (30 cases; age, 65.2 ± 8.1 years and the PPI group (30 cases; 65.2 ± 6.5 years. The diagnosis of delirium was based on the Diagnostic and Statistical Manual of Mental Disorders-IV-Text Revision. Delirium severity was rated on the Delirium Rating Scale (DRS. Results: The incidence of delirium was significantly lower in the PPI group than in the H2 group (p = 0.047. In the 11 patients from the H2 group who developed delirium, discontinuation of H2 blockers resulted in a significant reduction in the DRS score (p = 0.009. In three patients for whom H2 blockers were discontinued, DRS scores decreased by 50% or more three days after discontinuation compared to the prediscontinuation score. Conclusions: These results suggested that switching antiulcer drugs from H2 blockers to PPIs reduced delirium and thus provided an appropriate coping method for drug-induced delirium from antiulcer drugs.

  2. Anticonvulsant and neuroprotective effects of the novel calcium antagonist NP04634 on kainic acid-induced seizures in rats.

    Science.gov (United States)

    Morales-Garcia, Jose A; Luna-Medina, Rosario; Martinez, Ana; Santos, Angel; Perez-Castillo, Ana

    2009-12-01

    Kainic acid (KA)-induced status epilepticus (SE) is a well-characterized model of excitotoxic neuronal injury. Excitotoxicity results from activation of specific glutamate receptors, with resultant elevation of intracellular Ca(2+). The CA1 and CA3 subregions of the hippocampus are especially vulnerable to KA, and this pattern of neuronal injury resembles that occurring in patients with temporal lobe epilepsy. Calcium plays an essential role in excitotoxicity, and accordingly calcium channel inhibitors have been shown to have protective effects in various experimental models of epilepsy and brain injury. Moreover, they also potentiate the antiseizure efficacy of conventional antiepileptic drugs. This study was undertaken to determine whether NP04634, a novel compound, reported as a non-L-type voltage-sensitive calcium channel (VSCC) inhibitor, could prevent the entrance in SE and the neuronal loss evoked by intraperitoneal injection of KA. Our results show that intragastrical administration of NP04634 reduced the percentage of rats that entered SE after KA injection, increased the latency of SE entry, and significantly reduced the mortality of rats that entered SE. Also, NP04634 prevented the loss of hippocampal CA1 and CA3 pyramidal neurons and reduced the gliosis induced by KA. These results point to a potential anticonvulsant and neuroprotective role for NP04634. Copyright 2009 Wiley-Liss, Inc.

  3. Antagonist of peroxisome proliferator-activated receptor γ induces cerebellar amyloid-β levels and motor dysfunction in APP/PS1 transgenic mice

    International Nuclear Information System (INIS)

    Du, Jing; Sun, Bing; Chen, Kui; Fan, Li; Wang, Zhao

    2009-01-01

    Recent evidences show that peroxisome proliferator-activated receptor γ (PPARγ) is involved in the modulation of the amyloid-β (Aβ) cascade causing Alzheimer's disease (AD) and treatment with PPARγ agonists protects against AD pathology. However, the function of PPARγ steady-state activity in Aβ cascade and AD pathology remains unclear. In this study, an antagonist of PPARγ, GW9662, was injected into the fourth ventricle of APP/PS1 transgenic mice to inhibit PPARγ activity in cerebellum. The results show that inhibition of PPARγ significantly induced Aβ levels in cerebellum and caused cerebellar motor dysfunction in APP/PS1 transgenic mice. Moreover, GW9662 treatment markedly decreased the cerebellar levels of insulin-degrading enzyme (IDE), which is responsible for the cellular degradation of Aβ. Since cerebellum is spared from significant Aβ accumulation and neurotoxicity in AD patients and animal models, these findings suggest a crucial role of PPARγ steady-state activity in protection of cerebellum against AD pathology.

  4. Mechanisms and latest clinical studies of new NK1 receptor antagonists for chemotherapy-induced nausea and vomiting: Rolapitant and NEPA (netupitant/palonosetron).

    Science.gov (United States)

    Rojas, Camilo; Slusher, Barbara S

    2015-12-01

    Many patients undergoing moderately or highly emetogenic chemotherapy experience chemotherapy-induced nausea/vomiting (CINV) and report reduced daily functioning, despite prophylaxis with antiemetic drugs. While modern antiemetics have largely alleviated acute emesis, management of nausea and delayed emesis remains particularly challenging. We briefly review the pathophysiologic mechanisms of CINV and the clinical impact of current antiemetics, i.e., the serotonin subtype 3 (5-HT3) receptor antagonists (RAs) and neurokinin-1 (NK1)RAs, before summarizing recent data from clinical trials of new agents. The new antiemetics reviewed include the two most recently approved drugs, the NK1RA rolapitant and the fixed-dose combination product, NEPA, which is composed of the NK1RA netupitant and the 5-HT3RA palonosetron. Phase 3 studies demonstrate improved control of CINV in the delayed and overall phases when rolapitant is added to a standard 5-HT3RA regimen. Phase 2 and phase 3 clinical trials with NEPA demonstrate improved control of CINV in the acute, delayed, and overall phases vs. 5-HT3RA regimens. These data suggest that delayed emesis can be substantially reduced via combined 5-HT3 and NK1 receptor neurotransmitter pathway inhibition. Copyright © 2015 Elsevier Ltd. All rights reserved.

  5. Prolonged Survival in a Case of Chemotherapy-Sensitive Gastric Cancer That Produced Alpha-Fetoprotein and Protein Induced by Vitamin K Antagonist-II

    Directory of Open Access Journals (Sweden)

    Naotaka Ogasawara

    2015-04-01

    Full Text Available The number of reported cases of alpha-fetoprotein (AFP-producing gastric cancer has gradually increased, with a reported prevalence of 1.3-1.5% of all gastric cancer cases. However, reports of gastric cancer accompanied by elevated serum levels of both AFP and protein induced by vitamin K antagonist-II (PIVKA-II are rare. The prognosis of AFP- and PIVKA-II-producing gastric cancer has been reported to be very poor because the tumor cells were considered to have a high malignant potential and the cancer progressed rapidly. We described a case of gastric cancer producing AFP and PIVKA-II in which chemotherapy was effective and resulted in prolonged survival, and these two tumor markers were useful for monitoring the treatment response. Routine health screening using upper abdominal ultrasonography revealed hepatic tumors in an apparently healthy 65-year-old man. Whole-body computed tomography (CT revealed multiple hepatic tumors, and an esophagogastroduodenoscopy (EGD revealed a Bormann type 3 tumor in the lower stomach. A biopsy specimen confirmed that the tumor was immunohistochemically positive for AFP, PIVKA-II, and human epidermal growth factor receptor 2. After chemotherapy, the gastric tumor appeared as a small elevated lesion on EGD, and CT revealed a remarkable reduction in the size of the metastatic liver tumors. The patient is still alive, 35 months after the initial chemotherapy.

  6. The selective orexin receptor 1 antagonist ACT-335827 in a rat model of diet-induced obesity associated with metabolic syndrome

    Directory of Open Access Journals (Sweden)

    Michel Alexander Steiner

    2013-12-01

    Full Text Available The orexin system regulates feeding, nutrient metabolism and energy homeostasis. Acute pharmacological blockade of orexin receptor 1 (OXR-1 in rodents induces satiety and reduces normal and palatable food intake. Genetic OXR-1 deletion in mice improves hyperglycemia under high-fat (HF diet conditions. Here we investigated the effects of chronic treatment with the novel selective OXR-1 antagonist ACT-335827 in a rat model of diet-induced obesity (DIO associated with metabolic syndrome (MetS. Rats were fed either standard chow (SC or a cafeteria (CAF diet comprised of intermittent human snacks and a constant free choice between a HF/sweet (HF/S diet and SC for 13 weeks. Thereafter the SC group was treated with vehicle (for 4 weeks and the CAF group was divided into a vehicle and an ACT-335827 treatment group. Energy and water intake, food preference, and indicators of MetS (abdominal obesity, glucose homeostasis, plasma lipids, and blood pressure were monitored. Hippocampus-dependent memory, which can be impaired by DIO, was assessed. CAF diet fed rats treated with ACT-335827 consumed less of the HF/S diet and more of the SC, but did not change their snack or total kcal intake compared to vehicle-treated rats. ACT-335827 increased water intake and the high-density lipoprotein associated cholesterol proportion of total circulating cholesterol. ACT-335827 slightly increased body weight gain (4% versus controls and feed efficiency in the absence of hyperphagia. These effects were not associated with significant changes in the elevated fasting glucose and triglyceride (TG plasma levels, glucose intolerance, elevated blood pressure, and adiposity due to CAF diet consumption. Neither CAF diet consumption alone nor ACT-335827 affected memory. In conclusion, the main metabolic characteristics associated with DIO and MetS in rats remained unaffected by chronic ACT-335827 treatment, suggesting that pharmacological OXR-1 blockade has minimal impact in this

  7. Peripheral CB1 Receptor Neutral Antagonist, AM6545, Ameliorates Hypometabolic Obesity and Improves Adipokine Secretion in Monosodium Glutamate Induced Obese Mice

    Directory of Open Access Journals (Sweden)

    Haiming Ma

    2018-03-01

    Full Text Available Effect of peripheral cannabinoid receptor 1 (CB1R blockade by AM6545 in the monosodium glutamate (MSG-induced hypometabolic and hypothalamic obesity was observed, and the impact on intraperitoneal adipose tissue and adipokines was investigated. The MSG mice is characterized by excessive abdominal obesity, and combined with dyslipidemia and insulin resistance. 3-Week AM6545 treatment dose-dependently decreased the body weight, intraperitoneal fat mass, and rectified the accompanied dyslipidemia include elevated serum triglyceride, total cholesterol, free fatty acids, and lowered LDLc level. Glucose intolerance and hyperinsulinemia were also alleviated. But AM6545 didn’t affect the food-intake consistently through the experiment. In line with the reduction on fat mass, the size of adipocyte was reduced markedly. Most interestingly, AM6545 showed significant improvement on levels of circulating adipokines including lowering leptin, asprosin and TNFα, and increasing HMW adiponectin. Correspondingly, dysregulated gene expression of lipogenesis, lipolysis, and adipokines in the adipose tissue were nearly recovered to normal level after AM6545 treatment. Additionally, western blot analysis revealed that AM6545 corrected the elevated CB1R and PPARγ protein expression, while increased the key energy uncoupling protein UCP1 expression in adipose tissue. Taken together, the current study indicates that AM6545 induced a comprehensive metabolic improvement in the MSG mice including counteracting the hypometabolic and hypothalamic obesity, and improving the accompanied dyslipidemia and insulin resistance. One key underlying mechanism is related to ameliorate on the metabolic deregulation of adipose tissue, the synthesis and secretion of adipokines were thus rectified, and finally the catabolism was increased and the anabolism was reduced in intraperitoneal adipose tissue. Findings from this study will provide the valuable information about peripheral CB1R

  8. Protein induced by vitamin K absence or antagonist-II (PIVKA-II) specifically increased in Italian hepatocellular carcinoma patients.

    Science.gov (United States)

    Viggiani, Valentina; Palombi, Sara; Gennarini, Giuseppina; D'Ettorre, Gabriella; De Vito, Corrado; Angeloni, Antonio; Frati, Luigi; Anastasi, Emanuela

    2016-10-01

    As a marker for Hepatocellular Carcinoma (HCC), Protein Induced by Vitamin K Absence II (PIVKA-II) seems to be superior to alpha fetoprotein (AFP). To better characterize the role of PIVKA-II, both AFP and PIVKA-II have been measured in Italian patients with diagnosis of HCC compared with patients affected by non-oncological liver pathologies. Sixty serum samples from patients with HCC, 60 samples from patients with benign liver disease and 60 samples obtained from healthy blood donors were included in the study. PIVKA-II and AFP were measured by LUMIPULSE(®) G1200 (Fujirebio-Europe, Belgium). We considered as PIVKA-II cutoff 70 mAU/ml (mean +3SD) of the values observed in healthy subjects. The evaluation of PIVKA-II showed a positivity of 70% in patients with HCC and 5% in patients with benign diseases (p < 0.0001) whereas high levels of AFP were observed in 55% of HCC patients and in 47% of patients with benign diseases. The combined Receiver Operating Characteristic (ROC) analysis of the two analytes revealed a higher sensitivity (75%) compared to those observed for the individual biomarkers. In conclusion, we demonstrate that as a marker for HCC, PIVKA-II is more specific for HCC and less prone to elevation during chronic liver diseases. The combination of the two biomarkers, evaluated by the ROC analysis, improved the specificity compared to a single marker. These data suggest that the combined analysis of the two markers could be a useful tool in clinical practice.

  9. Effects of the cannabinoid CB1 receptor agonist CP55,940 and antagonist SR141716A on d-amphetamine-induced behaviours in Cebus monkeys

    DEFF Research Database (Denmark)

    Madsen, Morten V; Peacock, Linda; Werge, Thomas

    2006-01-01

    Several clinical studies have shown that alterations in the cannabinoid system in the brain may be associated with schizophrenia. Although evidence points towards an antipsychotic potential for cannabinoid antagonists, experimental studies have shown inconsistent behavioural effects of cannabinoid...

  10. Inhibition of tumor cell-induced platelet aggregation and lung metastasis by the oral GpIIb/IIIa antagonist XV454.

    Science.gov (United States)

    Amirkhosravi, Ali; Mousa, Shaker A; Amaya, Mildred; Blaydes, Susan; Desai, Hina; Meyer, Todd; Francis, John L

    2003-09-01

    Platelets are known to play a role in blood borne metastasis. Previous experimental studies have suggested that platelet GpIIb/IIIa may be a therapeutic target. However, the need for intravenous administration limits the potential application of current GpIIb/IIIa inhibitors to cancer therapy. The aim of the present study was to assess the efficacy of a novel, non-peptide oral GpIIb/IIIa antagonist (XV454) on tumor cell-induced platelet aggregation in vivo and on experimental metastasis. A Lewis lung carcinoma (LL2) mouse model of experimental metastasis was used in this study. XV454 (100 micro g) was administered intravenously (via tail vein) or orally (gavages) to 20 g mice. To determine the effect of XV454 on platelet aggregation, blood samples were collected by cardiac puncture 10 minutes after intravenous and 1-24 hrs after oral XV454, and platelet function was assessed by aggregometry, thrombelastography and the Platelet Function Analyzer (PFA100). The effect of XV454 on tumor cell-induced thrombocytopenia was determined 10 minutes after intravenous and 3 hrs after oral XV454 administration. Tumor cells (2 x 10(6)) were injected intravenously and 15 minutes after cell injection, platelet count was measured and compared to baseline (pre-injection) counts. To assess the effect on metastasis, XV454 was administered intravenous or orally 10 minutes and 3 hrs before tumor cell injection, respectively. Eighteen days later, surface lung tumor nodules were counted and the total lung tumor burden assessed. In a fourth group, in addition to the initial oral dose (before tumor cell injection), oral XV454 was given daily for the first week and three times in the second week. Administration of XV454 (5 mg/kg) completely inhibited platelet aggregation and this effect persisted for at least 24 hrs after oral delivery. Both intravenous and oral XV454 significantly inhibited tumor cell-induced thrombocytopenia (P < 0.01), the number of surface lung tumor nodules (80-85%; P

  11. Combined treatment with a β3 -adrenergic receptor agonist and a muscarinic receptor antagonist inhibits detrusor overactivity induced by cold stress in spontaneously hypertensive rats.

    Science.gov (United States)

    Imamura, Tetsuya; Ogawa, Teruyuki; Minagawa, Tomonori; Nagai, Takashi; Suzuki, Toshiro; Saito, Tetsuichi; Yokoyama, Hitoshi; Nakazawa, Masaki; Ishizuka, Osamu

    2017-04-01

    This study determined if combined treatment with the muscarinic receptor (MR) antagonist solifenacin and the β 3 -adrenergic receptor (AR) agonist mirabegron could inhibit detrusor overactivity induced by cold stress in spontaneously hypertensive rats (SHRs). Thirty-two female 10-week-old SHRs were fed an 8% NaCl-supplemented diet for 4 weeks. Cystometric measurements of the unanesthetized, unrestricted rats were performed at room temperature (RT, 27 ± 2°C) for 20 min. The rats were then intravenously administered vehicle, 0.1 mg/kg solifenacin alone, 0.1 mg/kg mirabegron alone, or the combination of 0.1 mg/kg mirabegron and 0.1 mg/kg solifenacin (n = 8 each group). Five minutes later, the treated rats were exposed to low temperature (LT, 4 ± 2°C) for 40 min. Finally, the rats were returned to RT. After the cystometric investigations, the β 3 -ARs and M 3 -MRs expressed within the urinary bladders were analyzed. Just after transfer from RT to LT, vehicle-, solifenacin-, and mirabegron-treated SHRs exhibited detrusor overactivity that significantly decreased voiding interval and bladder capacity. However, treatment with the combination of solifenacin and mirabegron partially inhibited the cold stress-induced detrusor overactivity patterns. The decreases of voiding interval and bladder capacity in the combination-treated rats were significantly inhibited compared to other groups. Within the urinary bladders, there were no differences between expression levels of M 3 -MR and β 3 -AR mRNA. The tissue distribution of M 3 -MRs was similar to that of the β 3 -ARs. This study suggested that the combination of solifenacin and mirabegron act synergistically to inhibit the cold stress-induced detrusor overactivity in SHRs. Neurourol. Urodynam. 36:1026-1033, 2017. © 2016 The Authors. Neurourology and Urodynamics Published by Wiley Periodicals, Inc. © 2016 The Authors. Neurourology and Urodynamics Published by Wiley Periodicals, Inc.

  12. Effect of the selective NMDA NR2B antagonist, ifenprodil, on acute tolerance to ethanol-induced motor impairment in adolescent and adult rats.

    Science.gov (United States)

    Ramirez, Ruby Liane; Varlinskaya, Elena I; Spear, Linda P

    2011-06-01

    Adolescent rats have been observed to be less sensitive than adults to a number of acute ethanol effects, including ethanol-induced motor impairment. These adolescent insensitivities may be related in part to the more rapid emergence of within session (acute) tolerance in adolescents than adults. Adolescent-related alterations in neural systems that serve as ethanol target sites, including changes in NMDA receptor subunit expression, may influence the responsiveness of adolescents to acute ethanol effects. This study explored the role of NMDA NR2B receptors in the development of acute tolerance to ethanol-induced motor impairment in male adolescent [postnatal day (P)28-30] and adult (P68-70) Sprague-Dawley rats. Motor-impairing effects of ethanol on the stationary inclined plane and blood ethanol concentrations (BECs) were examined following challenge at each age with a functionally equivalent ethanol dose (adolescents: 2.25 g/kg; adults: 1.5 g/kg). Data were collected at two postinjection intervals (10 or 60 minutes) to compare rate of recovery from ethanol intoxication with BEC declines using the Radlow approach (Radlow, 1994) and changes in motor impairment/BEC ratios over time for assessing acute tolerance. Both vehicle-treated adolescent and adult animals showed similar acute tolerance development to the motor-impairing effects of ethanol at these functionally equivalent doses on the stationary inclined plane, as indexed by an increasing time-dependent dissociation between BECs and ethanol-induced motor impairment, with motor impairment declining faster than BECs, as well as by significant declines in motor impairment/BEC ratios over time. Acute tolerance development was reliably blocked by administration of the NR2B antagonist, ifenprodil, (5.0 mg/kg), in adult rats, whereas adolescents were affected by a higher dose (10.0 mg/kg). These data support the suggestion that alterations in NMDA receptor systems occurring during adolescence may contribute to

  13. Investigating racial disparities in use of NK1 receptor antagonists to prevent chemotherapy-induced nausea and vomiting among women with breast cancer.

    Science.gov (United States)

    Check, Devon K; Reeder-Hayes, Katherine E; Basch, Ethan M; Zullig, Leah L; Weinberger, Morris; Dusetzina, Stacie B

    2016-04-01

    Chemotherapy-induced nausea and vomiting (CINV) is a major concern for cancer patients and, if uncontrolled, can seriously compromise quality of life (QOL) and other treatment outcomes. Because of the expense of antiemetic medications used to prevent CINV (particularly oral medications filled through Medicare Part D), disparities in their use may exist. We used 2006-2012 SEER-Medicare data to evaluate the use of neurokinin-1 receptor antagonists (NK1s), a potent class of antiemetics, among black and white women initiating highly emetogenic chemotherapy for the treatment of early-stage breast cancer. We used modified Poisson regression to assess the relationship between race and (1) any NK1 use, (2) oral NK1 (aprepitant) use, and (3) intravenous NK1 (fosaprepitant) use. We report adjusted risk ratios (aRR) and 95 % confidence intervals (CI). The study included 1130 women. We observed racial disparities in use of any NK1 (aRR: 0.68, 95 % CI 0.51-0.91) and in use of oral aprepitant specifically (aRR: 0.54, 95 % CI 0.35-0.83). We did not observe disparities in intravenous fosaprepitant use. After controlling for variables related to socioeconomic status, disparities in NK1 and aprepitant use were reduced but not eliminated. We found racial disparities in women's use of oral NK1s for the prevention of CINV. These disparities may be partly explained by racial differences in socioeconomic status, which may translate into differential ability to afford the medication.

  14. Prevention of drug priming- and cue-induced reinstatement of MDMA-seeking behaviors by the CB1 cannabinoid receptor antagonist AM251.

    Science.gov (United States)

    Nawata, Yoko; Kitaichi, Kiyoyuki; Yamamoto, Tsuneyuki

    2016-03-01

    3,4-Methylenedioxymethamphetamine (MDMA), a methamphetamine (METH) derivative, exhibits METH-like actions at monoamine transporters and positive reinforcing effects in rodents and primates. The purposes of the present study were to determine whether cross-reinstatement would be observed between MDMA and METH and if the cannabinoid receptor, a receptor known to play critical roles in the brain reward system, could modulate MDMA craving. Rats were trained to press a lever for intravenous MDMA (0.3mg/infusion) or METH (0.02mg/infusion) infusions under a fixed ratio 1 schedule paired with drug-associated cues (light and tone). Following drug self-administration acquisition training, rats underwent extinction training (an infusion of saline). Reinstatement tests were performed once the extinction criteria were achieved. In MDMA-trained rats, the MDMA-priming injection (3.2mg/kg, i.p.) or re-exposure to MDMA-associated cues reinstated MDMA-seeking behavior. Additionally, a priming injection of METH (1.0mg/kg, i.p.) also reinstated MDMA-seeking behavior. In contrast, none of the MDMA doses reinstated METH-seeking behavior in the METH-trained rats. The CB1 cannabinoid receptor antagonist AM251 markedly attenuated the MDMA-seeking behaviors induced by MDMA-priming injection or re-exposure to MDMA-associated cues in a dose-dependent manner. These findings show that MDMA has obvious addictive potential for reinstating drug-seeking behavior and that METH can be an effective stimulus for reinstating MDMA-seeking behaviors. Furthermore, based on the attenuating effect of AM251 in the reinstatement of MDMA-seeking behaviors, drugs that suppress CB1 receptors may be used in treatment of MDMA dependence. Copyright © 2016. Published by Elsevier Ireland Ltd.

  15. β(3)-Adrenoceptor Antagonist SR59230A Attenuates the Imbalance of Systemic and Myocardial Oxygen Transport Induced by Dopamine in Newborn Lambs.

    Science.gov (United States)

    Gill, Richdeep S; Cheung, Po-Yin; Yu, Xiaoyang; Aklabi, Mohammed Al; Nagendran, Jeevan; Quinonez, Luis G; Li, Ying Qian; Miller, John; Ross, David B; Rebeyka, Ivan M; Li, Jia

    2012-01-01

    In neonates, the increase in O(2)-delivery (DO(2)) by dopamine is offset by a greater increase in O(2)-consumption (VO(2)). This has been attributed to β(3)-adrenergic receptors in neonatal brown fat tissue. β(3) receptors in the heart have negative inotropic properties. We evaluated the effects of SR59230A, a β(3)-antagonist, on the balance of systemic and myocardial O(2)-transport in newborn lambs treated with dopamine. Lambs (2-5 days old, n = 12) were anesthetized and mechanically ventilated. Heart rate (HR) and rectal temperature were monitored. VO(2) was measured by respiratory mass spectrometry and cardiac output (CO) by a pulmonary artery transonic flowmeter. Arterial, jugular bulb venous and coronary sinus blood gases and lactate were measured to calculate DO(2), O(2) extraction ratio (ERO(2)), myocardial O(2) and lactate extraction ratios (mERO(2), mERlac). After baseline measurements, lambs were randomized to receive SR59230A at 5 mg/kg iv (SRG) or placebo. Both groups received incremental doses of a dopamine infusion (0-5-10-15-20 mcg/kg/min) every 15 min. Measurements were repeated at the end of each dose. After SR59230A infusion, CO and HR trended to decrease (P = 0.06), but no significant changes occurred in other parameters. Over the incremental doses of dopamine, temperature increased in both groups (P 0.1). DO(2) trended to a small increase (P = 0.08). VO(2) increased in both groups (P transport induced by dopamine at higher doses. Studies are warranted to examine the effect of SR59230A in cases of cardiac dysfunction and increased VO(2), observed after cardiac surgery.

  16. Alopecia induced by tumour necrosis factor-alpha antagonists: description of 52 cases and disproportionality analysis in a nationwide pharmacovigilance database.

    Science.gov (United States)

    Béné, Johana; Moulis, Guillaume; Auffret, Marine; Lefevre, Guillaume; Coquerelle, Pascal; Coupe, Patrick; Péré, Patrice; Gautier, Sophie

    2014-08-01

    The aim of this research was to describe the cases of TNF-α antagonist-related alopecia reported in the French Pharmacovigilance Database (FPVD) and to investigate the association between exposure to TNF-α antagonists and occurrence of alopecia. All spontaneous reports of TNF-α antagonist-related alopecia recorded in the FPVD between January 2000 and April 2012 were colligated and described. We conducted disproportionality analyses (case/non-case method) to assess the link between the occurrence of alopecia and exposure to TNF-α antagonists. Cases were all reports of alopecia and non-cases were all other reports recorded during the study period. Exposure to TNF-α antagonists was sought in cases and in non-cases. Reporting odds ratios (RORs) were calculated to assess the association. Docetaxel was used as positive control and acetaminophen as negative control. We performed sensitivity analyses excluding cases of androgenic alopecia and those occurring in psoriatic patients. Among 282 590 spontaneous reports of adverse drug reactions (ADRs) collated in the FPVD, 1068 cases (alopecia reports) were identified. Of these cases, 52 (4.9%) occurred during exposure to TNF-α antagonists (18 involved infliximab, 17 adalimumab, 15 etanercept and 2 certolizumab). Exposure to TNF-α antagonists was more frequent among alopecia reports than among other ADR reports for all TNF-α antagonists pooled (ROR 3.0, 95% CI 2.3, 4.0) as well as for each antagonist separately, with similar values. Sensitivity analyses yielded similar results. The RORs were 29.9 (95% CI 25.3, 35.5) with docetaxel and 0.3 (95% CI 0.2, 0.4) with acetaminophen. The present study confirms a strong link between TNF-α antagonist exposure (class effect) and the occurrence of alopecia. © The Author 2014. Published by Oxford University Press on behalf of the British Society for Rheumatology. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  17. Thrombin-receptor antagonist vorapaxar in acute coronary syndromes

    DEFF Research Database (Denmark)

    Tricoci, Pierluigi; Huang, Zhen; Held, Claes

    2012-01-01

    Vorapaxar is a new oral protease-activated-receptor 1 (PAR-1) antagonist that inhibits thrombin-induced platelet activation.......Vorapaxar is a new oral protease-activated-receptor 1 (PAR-1) antagonist that inhibits thrombin-induced platelet activation....

  18. PXR antagonists and implication in drug metabolism

    Science.gov (United States)

    Mani, Sridhar; Dou, Wei; Redinbo, Matthew R.

    2013-01-01

    Adopted orphan nuclear receptor (NR), pregnane X receptor (PXR), plays a central role in the regulation of xeno- and endobiotic metabolism. Since the discovery of the functional role of PXR in 1998, there is evolving evidence for the role of PXR agonists in abrogating metabolic pathophysiology (e.g., cholestasis, hypercholesterolemia, and inflammation). However, more recently, it is clear that PXR is also an important mediator of adverse xeno- (e.g., enhances acetaminophen toxicity) and endobiotic (e.g., hepatic steatosis) metabolic phenotypes. Moreover, in cancer therapeutics, PXR activation can induce drug resistance, and there is growing evidence for tissue-specific enhancement of the malignant phenotype. Thus, in these instances, there may be a role for PXR antagonists. However, as opposed to the discovery efforts for PXR agonists, there are only a few antagonists described. The mode of action of these antagonists (e.g., sulforaphane) remains less clear. Our laboratory efforts have focused on this question. Since the original discovery of azoles analogs as PXR antagonists, we have preliminarily defined an important PXR antagonist pharmacophore and developed less-toxic PXR antagonists. In this review, we describe our published and unpublished findings on recent structure-function studies involving the azole chemical scaffold. Further work in the future is needed to fully define potent, more-selective PXR antagonists that may be useful in clinical application. PMID:23330542

  19. Effects of the calcium channel antagonist mibefradil on haemodynamic and morphological parameters in myocardial infarction-induced cardiac failure in rats

    NARCIS (Netherlands)

    Sandmann, S.; Spitznagel, H.; Chung, O.; Xia, Q. G.; Illner, S.; Jänichen, G.; Rossius, B.; Daemen, M. J.; Unger, T.

    1998-01-01

    Calcium channel antagonists (CCA) have been proposed for the prevention of cardiac events after myocardial infarction (MI). Mibefradil is a CCA featuring a selective blockade of T-type Ca2(+)-channels. The aim of the study was to characterize the effects of mibefradil on haemodynamic and

  20. A peptide antagonist of ErbB receptors, Inherbin3, induces neurite outgrowth from rat cerebellar granule neurons through ErbB1 inhibition

    DEFF Research Database (Denmark)

    Xu, Ruodan; Pankratova, Stanislava; Christiansen, Søren Hofman

    2013-01-01

    ErbB receptors not only function in cancer, but are also key developmental regulators in the nervous system. We previously identified an ErbB1 peptide antagonist, Inherbin3, that is capable of inhibiting tumor growth in vitro and in vivo. In this study, we found that inhibition of ErbB1 kinase...

  1. Smac mimetics as IAP antagonists.

    Science.gov (United States)

    Fulda, Simone

    2015-03-01

    As the Inhibitor of Apoptosis (IAP) proteins are expressed at high levels in human cancers, they represent promising targets for therapeutic intervention. Small-molecule inhibitors of IAP proteins mimicking the endogenous IAP antagonist Smac, called Smac mimetics, neutralize IAP proteins and thereby promote the induction of cell death. Smac mimetics have been shown in preclinical models of human cancer to directly trigger cancer cell death or to sensitize for cancer cell death induced by a variety of cytotoxic stimuli. Smac mimetics are currently undergoing clinical evaluation in phase I/II trials, demonstrating that therapeutic targeting of IAP proteins has reached the clinical stage. Copyright © 2015 Elsevier Ltd. All rights reserved.

  2. The angiotensin II AT1 receptor antagonist irbesartan prevents thromboxane A2-induced vasoconstriction in the rat hind-limb vascular bed in vivo.

    Science.gov (United States)

    Fukuhara, M; Neves, L A; Li, P; Diz, D I; Ferrario, C M; Brosnihan, K B

    2001-03-01

    We studied the vasoconstrictor effects of the thromboxane A2 (TxA2) analogue U46619 in the perfused hind limb of rats under constant flow before and after intravenous injection of irbesartan, an angiotensin II AT1 receptor antagonist, to test whether irbesartan interacts in vivo with the thromboxane A2/prostaglandin endoperoxidase H2 (TxA2/PGH2) receptor. Male Sprague-Dawley rats (n = 15, body weight 350-420 g) were anesthetized with thiobutabarbital sodium (Inactin, 100 mg/kg intraperitoneally). Regional vascular responses to U46619 (0.5 and 1.0 microg) were investigated in the rat hind quarter under conditions of controlled flow before and after administration of irbesartan (10 mg/kg, intravenously). In addition, to test the specificity of the effect of irbesartan on U46619, phenylephrine (0.5, 1.0 microg) and another AT1 receptor antagonist, candesartan CV11974 (0.3 mg/kg, intravenously) were used. The dose-dependent increases in hind-limb perfusion pressure produced by U46619 were significantly attenuated by prior injection of irbesartan, at a dose that blocked the angiotensin II (Ang II) pressor responses. The specificity for the response was shown with the demonstrations that the increase in vascular resistance produced by phenylephrine was unchanged by irbesartan and, furthermore, that the increase in vascular resistance produced by U46619 was unchanged by another AT1 receptor antagonist, candesartan. This study demonstrates that irbesartan interacts at the TxA2/PGH2 receptor in the rat's hind limb in vivo, to modify changes in local regional vascular resistance. The dual antagonistic actions of irbesartan, acting at both AT1 and TxA2 receptors in blood vessels, may overall enhance its therapeutic profile in the treatment of hypertension.

  3. Abiotic conditions affect floral antagonists and mutualists of Impatiens capensis (Balsaminaceae).

    Science.gov (United States)

    Soper Gorden, Nicole L; Adler, Lynn S

    2013-04-01

    While the effect of abiotic factors on leaf herbivory is well known, the relative importance of abiotic conditions influencing both mutualists and antagonists is less well understood. Species interactions could enhance or reduce the direct effects of abiotic factors, depending on how mutualists and antagonists respond to abiotic conditions. We manipulated soil nutrients and shade in a factorial design and measured soil moisture in the annual Impatiens capensis. We then measured interactions with mutualists (two pollinating species) and antagonists (herbivores, florivores, nectar thieves, and flower bud gallers), as well as plant growth, floral rewards, and plant reproduction. Fertilizer increased plant growth, floral attractiveness, mutualist and antagonist interactions, and plant reproduction. Shade had no effects, and soil moisture was negatively associated with plant growth and reproduction. All effects were additive. Mutualist and antagonist floral interactions both increased on fertilized plants, but antagonists increased at a greater rate, leading to a larger ratio of antagonist to mutualist interactions on fertilized plants. Despite having more antagonists, fertilized plants still had significantly higher reproduction, suggesting higher tolerance to antagonists. Abiotic effects can have consistent effects on antagonists and mutualists, and on both floral and leaf antagonists. However, tolerance to antagonisms increased in favorable conditions. Thus, the direct positive effects of favorable abiotic conditions on plants outweighed negative indirect effects via increased antagonisms, which may lead to selection to grow in high-nutrient microsites in spite of increased herbivory.

  4. Effects of kinin B(1) and B(2) receptor antagonists on overactive urinary bladder syndrome induced by spinal cord injury in rats.

    Science.gov (United States)

    Forner, Stefânia; Andrade, Edinéia L; Martini, Alessandra C; Bento, Allisson F; Medeiros, Rodrigo; Koepp, Janice; Calixto, João B

    2012-12-01

    Kinin B(1) and B(2) receptors have been implicated in physiological and pathological conditions of the urinary bladder. However, their role in overactive urinary bladder (OAB) syndrome following spinal cord injury (SCI) remains elusive. We investigated the role of kinin B(1) and B(2) receptors in OAB after SCI in rats. SCI was associated with a marked inflammatory response and functional changes in the urinary bladder. SCI resulted in an up-regulation of B(1) receptor mRNA in the urinary bladder, dorsal root ganglion and spinal cord, as well as in B(1) protein in the urinary bladder and B(1) and B(2) receptor protein in spinal cord. Interestingly, both B(1) and B(2) protein expression were similarly distributed in detrusor muscle and urothelium of animals with SCI. In vitro stimulation of urinary bladder with the selective B(1) or B(2) agonist elicited a higher concentration-response curve in the SCI urinary bladder than in naive or sham urinary bladders. Cystometry revealed that treatment of SCI animals with the B(2) selective antagonist icatibant reduced the amplitude and number of non-voiding contractions (NVCs). The B(1) antagonist des-Arg(9) -[Leu(8) ]-bradykinin reduced the number of NVCs while the non-peptide B(1) antagonist SSR240612 reduced the number of NVCs, the urinary bladder capacity and increased the voiding efficiency and voided volume. Taken together, these data show the important roles of B(1) and B(2) receptors in OAB following SCI in rats and suggest that blockade of these receptors could be a potential therapeutic target for controlling OAB. © 2012 The Authors. British Journal of Pharmacology © 2012 The British Pharmacological Society.

  5. Effects of kinin B1 and B2 receptor antagonists on overactive urinary bladder syndrome induced by spinal cord injury in rats

    Science.gov (United States)

    Forner, Stefânia; Andrade, Edinéia L; Martini, Alessandra C; Bento, Allisson F; Medeiros, Rodrigo; Koepp, Janice; Calixto, João B

    2012-01-01

    Background and Purpose Kinin B1 and B2 receptors have been implicated in physiological and pathological conditions of the urinary bladder. However, their role in overactive urinary bladder (OAB) syndrome following spinal cord injury (SCI) remains elusive. Experimental Approach We investigated the role of kinin B1 and B2 receptors in OAB after SCI in rats. Key Results SCI was associated with a marked inflammatory response and functional changes in the urinary bladder. SCI resulted in an up-regulation of B1 receptor mRNA in the urinary bladder, dorsal root ganglion and spinal cord, as well as in B1 protein in the urinary bladder and B1 and B2 receptor protein in spinal cord. Interestingly, both B1 and B2 protein expression were similarly distributed in detrusor muscle and urothelium of animals with SCI. In vitro stimulation of urinary bladder with the selective B1 or B2 agonist elicited a higher concentration-response curve in the SCI urinary bladder than in naive or sham urinary bladders. Cystometry revealed that treatment of SCI animals with the B2 selective antagonist icatibant reduced the amplitude and number of non-voiding contractions (NVCs). The B1 antagonist des-Arg9-[Leu8]-bradykinin reduced the number of NVCs while the non-peptide B1 antagonist SSR240612 reduced the number of NVCs, the urinary bladder capacity and increased the voiding efficiency and voided volume. Conclusions and Implications Taken together, these data show the important roles of B1 and B2 receptors in OAB following SCI in rats and suggest that blockade of these receptors could be a potential therapeutic target for controlling OAB. PMID:22862305

  6. Prevention of Spinal Anesthesia-Induced Hypotension During Cesarean Delivery by 5-Hydroxytryptamine-3 Receptor Antagonists: A Systematic Review and Meta-analysis and Meta-regression.

    Science.gov (United States)

    Heesen, Michael; Klimek, Markus; Hoeks, Sanne E; Rossaint, Rolf

    2016-10-01

    Hypotension remains a frequent complication of spinal anesthesia, increasing the risk of nausea and vomiting, altered mental status, and aspiration. The aim of this systematic review and meta-analysis was to determine whether 5-hydroxytryptamine3 (5-HT3) receptor antagonists, administered before the initiation of spinal anesthesia, mitigate hypotension. After a systematic literature search in various databases, randomized placebo-controlled double-blind trials studying the preventive effect of 5-HT3 receptor antagonists were included. A random-effects model was applied, risk ratio (RR, binary variables) or weighted mean difference (continuous variables) with 95% confidence intervals (CIs) were calculated. The primary outcome was the incidence of hypotension. Seventeen trials (8 obstetric, 9 non-obstetric) reporting on 1604 patients were identified. Ondansetron in doses from 2 to 12 mg was studied in 12 trials. Prophylactic 5-HT3 administration significantly reduced the risk of hypotension in the combined analysis of 17 trials, RR 0.54 (95% CI 0.36-0.81, I = 79%). In obstetric trials, the RR was 0.52, 95% CI 0.30-0.88, I = 87% (number needed to treat 4). In non-obstetric studies, the 95% CIs were wide and included a clinically relevant reduction in the risk of hypotension (RR 0.50, 95% CI 0.22-1.16; I = 66%). Contour-enhanced funnel plots confirmed publication bias. Meta-regression showed a significant ondansetron dose response in non-obstetric patients (β = -0.355, P = .04). In the combined and in the obstetric-only analysis, the risk of bradycardia was significantly reduced as was the use of phenylephrine equivalents. 5-HT3 antagonists are effective in reducing the incidence of hypotension and bradycardia; the effects are moderate and are only significant in the subgroup of patients undergoing cesarean delivery. The effects in the non-obstetric population are not significant.

  7. FAVORING PARTIES BY GENERAL LINEAR DIVISOR METHOD

    Directory of Open Access Journals (Sweden)

    Ion BOLUN

    2016-03-01

    Full Text Available Aspects of General Linear Divisor (GLDmethod favoring of parties, when distributing seats, are investigated. They are identified predisposing conditions of a particular party to favor parties and also the fact that predisposition of favoring smaller parties is increasing, and of favoring of larger parties is decreasing with the increase of constant c value. The condition of Hamilton equilibrium between two parties is defined and special cases of Hamilton equilibriumand quasi-equilibrium are described. Are identified areas of GLD method favoring of larger and of smaller parties depending on the number of parties and on values of constant c and ΔM. Onaverage, GLD method favors large parties at c 2 and did not favor any party at c = 2.

  8. Coronary dilation with nitrocompounds and calcium antagonists.

    Science.gov (United States)

    Jost, S; Rafflenbeul, W; Lichtlen, P R

    1990-01-01

    The vasodilatory effects of nitrocompounds and calcium antagonists on epicardial coronary arteries represent substantial antianginal mechanisms in the presence of coronary vasospasm or eccentric coronary stenoses. With high doses of nitrocompounds, angiographically normal coronary segments can be dilated by an average of approx. 30%, some coronary stenoses even by up to 100%, usually without severe reduction of blood pressure. With calcium antagonists, a similar extent of dilation of normal coronary arteries and eccentric stenoses can be obtained. Our own group demonstrated an average dilation of normal coronary arteries of about 20% after intravenous administration of dihydropyridine calcium antagonists; however, the average systolic blood pressure dropped below 100 mmHg after these compounds. Hence, although in isolated human coronary arteries high concentrations of calcium antagonists were shown to induce a considerably greater vasodilation than nitrocompounds, the early drop in blood pressure prohibits a higher dosage of calcium antagonists in vivo. In the presence of coronary artery disease, particularly when associated with coronary vasospasm, a combination of the two groups of compounds might be recommendable, since an addition of the effects of coronary vasomotor tone is likely. Furthermore, the antianginal effects of a reduction of preload and afterload are complementary.

  9. Gastric myoelectric activity during cisplatin-induced acute and delayed emesis reveals a temporal impairment of slow waves in ferrets: effects not reversed by the GLP-1 receptor antagonist, exendin (9-39).

    Science.gov (United States)

    Lu, Zengbing; Ngan, Man P; Lin, Ge; Yew, David T W; Fan, Xiaodan; Andrews, Paul L R; Rudd, John A

    2017-11-17

    Preclinical studies show that the glucagon-like peptide-1 (GLP-1) receptor antagonist, exendin (9-39), can reduce acute emesis induced by cisplatin. In the present study, we investigate the effect of exendin (9-39) (100 nmol/24 h, i.c.v), on cisplatin (5 mg/kg, i.p.)-induced acute and delayed emesis and changes indicative of 'nausea' in ferrets. Cisplatin induced 37.2 ± 2.3 and 59.0 ± 7.7 retches + vomits during the 0-24 (acute) and 24-72 h (delayed) periods, respectively. Cisplatin also increased ( P Advanced multifractal detrended fluctuation analysis revealed that the slow wave signal shape became more simplistic during delayed emesis. Cisplatin did not affect blood pressure (BP), but transiently increased heart rate, and decreased heart rate variability (HRV) during acute emesis; HRV spectral analysis indicated a shift to 'sympathetic dominance'. A hyperthermic response was seen during acute emesis, but hypothermia occurred during delayed emesis and there was also a decrease in HR. Exendin (9-39) did not improve feeding and drinking but reduced cisplatin-induced acute emesis by ~59 % ( P waves may represent a novel approach to treat the side effects of chemotherapy.

  10. Non-Selective Cannabinoid Receptor Antagonists, Hinokiresinols Reduce Infiltration of Microglia/Macrophages into Ischemic Brain Lesions in Rat via Modulating 2-Arachidonolyglycerol-Induced Migration and Mitochondrial Activity.

    Directory of Open Access Journals (Sweden)

    Angela M A Anthony Jalin

    Full Text Available Growing evidence suggests that therapeutic strategies to modulate the post-ischemic inflammatory responses are promising approaches to improve stroke outcome. Although the endocannabinoid system has been emerged as an endogenous therapeutic target to regulate inflammation after stroke insult, the downstream mechanisms and their potentials for therapeutic intervention remain controversial. Here we identified trans- and cis-hinokiresinols as novel non-selective antagonists for two G-protein-coupled cannabinoid receptors, cannabinoid receptor type 1 and type 2. The Electric Cell-substrate Impedance Sensing and Boyden chamber migration assays using primary microglial cultures revealed that both hinokiresinols significantly inhibited an endocannabinoid, 2-arachidonoylglycerol-induced migration. Hinokiresinols modulated 2-arachidonoylglycerol-induced mitochondrial bioenergetics in microglia as evidenced by inhibition of ATP turnover and reduction in respiratory capacity, thereby resulting in impaired migration activity. In rats subjected to transient middle cerebral artery occlusion (1.5-h followed by 24-h reperfusion, post-ischemic treatment with hinokiresinols (2 and 7-h after the onset of ischemia, 10 mg/kg significantly reduced cerebral infarct and infiltration of ED1-positive microglial/macrophage cells into cerebral ischemic lesions in vivo. Co-administration of exogenous 2-AG (1 mg/kg, i.v., single dose at 2 h after starting MCAO abolished the protective effect of trans-hinokiresionol. These results suggest that hinokiresinols may serve as stroke treatment by targeting the endocannabinoid system. Alteration of mitochondrial bioenergetics and consequent inhibition of inflammatory cells migration may be a novel mechanism underlying anti-ischemic effects conferred by cannabinoid receptor antagonists.

  11. A novel 5HT3 antagonist 4i (N-(3-chloro-2-methylphenyl)quinoxalin-2-carboxamide) prevents diabetes-induced depressive phenotypes in mice: Modulation of serotonergic system.

    Science.gov (United States)

    Gupta, Deepali; Thangaraj, Devadoss; Radhakrishnan, Mahesh

    2016-01-15

    Despite the presence of a multitudinous pharmacotherapy, diabetes-induced depressive disorder remains undertreated. Evidence suggests that brain serotonergic deficits are associated with depressive-like behavior in diabetes and that 5HT3 receptor (5HT3R) antagonists have serotonergic facilitatory effects. This study examined the effects of a novel 5HT3R antagonist, 4i (N-(3-chloro-2-methylphenyl)quinoxalin-2-carboxamide), in diabetes-induced depressive phenotypes. Experimentally, (1) to evaluate the effects of 4i, mice with 8-weeks of diabetes (induced by streptozotocin, 200mg/kg, i.p.) were treated with vehicle, 4i (0.5 and 1mg/kg/day, i.p.), fluoxetine (10mg/kg/day, i.p.) for 4-weeks and subjected to neurobehavioral assays, followed by biochemical estimation of serotonin levels in midbrain, prefrontal-cortex and cerebellum. (2) To evaluate the role of 5HT3R in the postulated effect of 4i, diabetic mice were given 4i (1mg/kg/day, i.p.) after 1h of 1-(m-chlorophenyl)-biguanide (mCPBG, a 5HT3R agonist, 10mg/kg/day, i.p.) treatment and subjected to the same protocol. The results showed that diabetic mice exhibited a significant behavioral deficit, including depression-like behavior in forced swim test, anxiety-like in open field test and sociability deficits in social interaction test, along with a significant decrease in serotonin level in these brain regions. 4i (1mg/kg), similar to fluoxetine, prevented these behavioral abnormalities and normalized brain serotonin levels. 4i (0.5mg/kg) ameliorated only diabetes-induced depressive-like behavior and serotonin deficits, but not anxiety-like effects. mCPBG blunted 4i-mediated behavioral response and increase in brain serotonin levels. Altogether, this study suggests that 4i prevents diabetes-induced depressive phenotypes in mice, which may involve antagonism of 5HT3Rs and increase in serotonin levels in discrete brain regions. Copyright © 2015 Elsevier B.V. All rights reserved.

  12. T-type calcium channel antagonists, mibefradil and NNC-55-0396 inhibit cell proliferation and induce cell apoptosis in leukemia cell lines.

    Science.gov (United States)

    Huang, Weifeng; Lu, Chunjing; Wu, Yong; Ouyang, Shou; Chen, Yuanzhong

    2015-05-21

    T-type Ca(2+) channels are often aberrantly expressed in different human cancers and participate in the regulation of cell cycle progression, proliferation and death. RT-PCR, Q-PCR, western blotting and whole-cell patch-clamp recording were employed to assess the expression of T-type Ca(2+) channels in leukemia cell lines. The function of T-type Ca(2+) channels in leukemia cell growth and the possible mechanism of the effect of T-type Ca(2+) channel antagonists on cell proliferation and apoptosis were examined in T-lymphoma cell lines. We show that leukemia cell lines exhibited reduced cell growth when treated with T-type Ca(2+) channel inhibitors, mibefradil and NNC-55-0396 in a concentration-dependent manner. Mechanistically, these inhibitors played a dual role on cell viability: (i) blunting proliferation, through a halt in the progression to the G1-S phase; and (ii) promoting cell apoptosis, partially dependent on the endoplasmic reticulum Ca(2+) release. In addition, we observed a reduced phosphorylation of ERK1/2 in MOLT-4 cells in response to mibefradil and NNC-55-0396 treatment. These results indicate that mibefradil and NNC-55-0396 regulate proliferation and apoptosis in T-type Ca(2+) channel expressing leukemia cell lines and suggest a potential therapeutic target for leukemia.

  13. Memantine, an antagonist of the NMDA glutamate receptor, affects cell proliferation, differentiation and the intracellular cycle and induces apoptosis in Trypanosoma cruzi.

    Directory of Open Access Journals (Sweden)

    Flávia Silva Damasceno

    2014-02-01

    Full Text Available Chagas' disease is caused by the protozoan parasite Trypanosoma cruzi and affects approximately 10 million people in endemic areas of Mexico and Central and South America. Currently available chemotherapies are limited to two compounds: Nifurtimox and Benznidazole. Both drugs reduce the symptoms of the disease and mortality among infected individuals when used during the acute phase, but their efficacy during the chronic phase (during which the majority of cases are diagnosed remains controversial. Moreover, these drugs have several side effects. The aim of this study was to evaluate the effect of Memantine, an antagonist of the glutamate receptor in the CNS of mammals, on the life cycle of T. cruzi. Memantine exhibited a trypanocidal effect, inhibiting the proliferation of epimastigotes (IC50 172.6 µM. Furthermore, this compound interfered with metacyclogenesis (approximately 30% reduction and affected the energy metabolism of the parasite. In addition, Memantine triggered mechanisms that led to the apoptosis-like cell death of epimastigotes, with extracellular exposure of phosphatidylserine, increased production of reactive oxygen species, decreased ATP levels, increased intracellular Ca(2+ and morphological changes. Moreover, Memantine interfered with the intracellular cycle of the parasite, specifically the amastigote stage (IC50 31 µM. Interestingly, the stages of the parasite life cycle that require more energy (epimastigote and amastigote were more affected as were the processes of differentiation and cell invasion.

  14. Antagonistic parent-offspring co-adaptation.

    Directory of Open Access Journals (Sweden)

    Mathias Kölliker

    2010-01-01

    Full Text Available In species across taxa, offspring have means to influence parental investment (PI. PI thus evolves as an interacting phenotype and indirect genetic effects may strongly affect the co-evolutionary dynamics of offspring and parental behaviors. Evolutionary theory focused on explaining how exaggerated offspring solicitation can be understood as resolution of parent-offspring conflict, but the evolutionary origin and diversification of different forms of family interactions remains unclear.In contrast to previous theory that largely uses a static approach to predict how "offspring individuals" and "parental individuals" should interact given conflict over PI, we present a dynamic theoretical framework of antagonistic selection on the PI individuals obtain/take as offspring and the PI they provide as parents to maximize individual lifetime reproductive success; we analyze a deterministic and a stochastic version of this dynamic framework. We show that a zone for equivalent co-adaptation outcomes exists in which stable levels of PI can evolve and be maintained despite fast strategy transitions and ongoing co-evolutionary dynamics. Under antagonistic co-adaptation, cost-free solicitation can evolve as an adaptation to emerging preferences in parents.We show that antagonistic selection across the offspring and parental life-stage of individuals favors co-adapted offspring and parental behavior within a zone of equivalent outcomes. This antagonistic parent-offspring co-adaptation does not require solicitation to be costly, allows for rapid divergence and evolutionary novelty and potentially explains the origin and diversification of the observed provisioning forms in family life.

  15. Postmating sexual selection favors males that sire offspring with low fitness

    DEFF Research Database (Denmark)

    Bilde, T.; Foged, Anne; Schilling, Nadia

    2009-01-01

    Despite the costs of mating, females of most taxa mate with multiple males. Polyandrous females are hypothesized to gain genetic benefits for their offspring, but this assumes paternity bias favoring male genotypes that enhance offspring viability. We determined net male genetic effects on female...... results imply that sexually antagonistic adaptations have a major and unappreciated influence on male postmating fertilization success. Such genetic variation renders indirect genetic benefits an unlikely driver of the evolution of polyandry....

  16. Administration of the GABAA receptor antagonist picrotoxin into rat supramammillary nucleus induces c-Fos in reward-related brain structures. Supramammillary picrotoxin and c-Fos expression

    Directory of Open Access Journals (Sweden)

    Shin Rick

    2010-08-01

    Full Text Available Abstract Background Picrotoxin blocks GABAA receptors, whose activation typically inhibits neuronal firing activity. We recently found that rats learn to selectively self-administer picrotoxin or bicuculline, another GABAA receptor antagonist, into the supramammillary nucleus (SuM, a posterior hypothalamic structure localized anterior to the ventral tegmental area. Other drugs such as nicotine or the excitatory amino acid AMPA are also self-administered into the SuM. The SuM appears to be functionally linked with the mesolimbic dopamine system and is closely connected with other brain structures that are implicated in motivational processes, including the prefrontal cortex, septal area, preoptic area, lateral hypothalamic area and dorsal raphe nucleus. Here, we hypothesized that these brain structures are activated by picrotoxin injections into the SuM. Results Picrotoxin administration into the SuM markedly facilitated locomotion and rearing. Further, it increased c-Fos expression in this region, suggesting blockade of tonic inhibition and thus the disinhibition of local neurons. This manipulation also increased c-Fos expression in structures including the ventral tegmental area, medial shell of the nucleus accumbens, medial prefrontal cortex, septal area, preoptic area, lateral hypothalamic area and dorsal raphe nucleus. Conclusions Picrotoxin administration into the SuM appears to disinhibit local neurons and recruits activation of brain structures associated with motivational processes, including the mesolimbic dopamine system, prefrontal cortex, septal area, preoptic area, lateral hypothalamic area and dorsal raphe nucleus. These regions may be involved in mediating positive motivational effects triggered by intra-SuM picrotoxin.

  17. Sleep Deprivation-Induced Blood-Brain Barrier Breakdown and Brain Dysfunction are Exacerbated by Size-Related Exposure to Ag and Cu Nanoparticles. Neuroprotective Effects of a 5-HT3 Receptor Antagonist Ondansetron.

    Science.gov (United States)

    Sharma, Aruna; Muresanu, Dafin F; Lafuente, José V; Patnaik, Ranjana; Tian, Z Ryan; Buzoianu, Anca D; Sharma, Hari S

    2015-10-01

    Military personnel are often subjected to sleep deprivation (SD) during combat operations. Since SD is a severe stress and alters neurochemical metabolism in the brain, a possibility exists that acute or long-term SD will influence blood-brain barrier (BBB) function and brain pathology. This hypothesis was examined in young adult rats (age 12 to 14 weeks) using an inverted flowerpot model. Rats were placed over an inverted flowerpot platform (6.5 cm diameter) in a water pool where the water levels are just 3 cm below the surface. In this model, animals can go to sleep for brief periods but cannot achieve deep sleep as they would fall into water and thus experience sleep interruption. These animals showed leakage of Evans blue in the cerebellum, hippocampus, caudate nucleus, parietal, temporal, occipital, cingulate cerebral cortices, and brain stem. The ventricular walls of the lateral and fourth ventricles were also stained blue, indicating disruption of the BBB and the blood-cerebrospinal fluid barrier (BCSFB). Breakdown of the BBB or the BCSFB fluid barrier was progressive in nature from 12 to 48 h but no apparent differences in BBB leakage were seen between 48 and 72 h of SD. Interestingly, rats treated with metal nanoparticles, e.g., Cu or Ag, showed profound exacerbation of BBB disruption by 1.5- to 4-fold, depending on the duration of SD. Measurement of plasma and brain serotonin showed a close correlation between BBB disruption and the amine level. Repeated treatment with the serotonin 5-HT3 receptor antagonist ondansetron (1 mg/kg, s.c.) 4 and 8 h after SD markedly reduced BBB disruption and brain pathology after 12 to 24 h SD but not following 48 or 72 h after SD. However, TiO2-nanowired ondansetron (1 mg/kg, s.c) in an identical manner induced neuroprotection in rats following 48 or 72 h SD. However, plasma and serotonin levels were not affected by ondansetron treatment. Taken together, our observations are the first to show that (i) SD could induce BBB

  18. The tachykinins substance P and hemokinin-1 favor the generation of human memory Th17 cells by inducing IL-1β, IL-23, and TNF-like 1A expression by monocytes.

    Science.gov (United States)

    Cunin, Pierre; Caillon, Antoine; Corvaisier, Murielle; Garo, Erwan; Scotet, Mari; Blanchard, Simon; Delneste, Yves; Jeannin, Pascale

    2011-04-01

    The nervous system influences immune responses through the release of neural factors such as neuropeptides. Among them, the tachykinin substance P (SP) signals via the neurokinin 1 receptor (NK-1R), which is expressed by various immune cells. We thereby analyzed in this paper whether tachykinins may participate in human CD4(+) Th cell polarization. We report that SP and hemokinin-1 (HK-1) upregulate IL-17A and IFN-γ production by human memory CD4(+) T cells without affecting IL-4 and IL-10 production. SP and HK-1 switch non-Th17-committed CD4(+) memory T cells into bona fide Th17 cells and Th1/Th17 cells. In contrast, SP and HK-1 do not modulate the polarization of naive CD4(+) T cells. SP- and HK-1-induced Th17 cell generation is mediated through NK-1R and requires the presence of monocytes. SP and HK-1 trigger IL-1β, IL-6, and TNF-α production, upregulate IL-23 production, and enhance TNF-like 1A expression on monocyte surface. Neutralization experiments demonstrated that IL-1β, IL-23, and TNF-like 1A are involved in the SP- and HK-1-induced Th17 cell. The other members of the tachykinin family, neurokinins A and B, have no effect on the differentiation of naive and memory T cells. These results thereby show that SP and HK-1 are novel Th17 cell-inducing factors that may act locally on memory T cells to amplify inflammatory responses.

  19. Oxytocin antagonist disrupts hypotension-evoked renin secretion and other responses in conscious rats

    DEFF Research Database (Denmark)

    Huang, W.; Sjöquist, M.; Skøtt, O.

    2001-01-01

    antagonist did not alter the hypotension induced by hydralazine or diazoxide, but it did markedly blunt the induced increase in PRA. The OT receptor antagonist also blunted the hypotension-evoked increase in heart rate and plasma vasopressin levels, suggesting that the antagonist may have generally disrupted...... afferent signaling of hypotension. Thus hypotension-evoked OT secretion may contribute to cardiovascular homeostasis by enhancing baroreceptor signals that stimulate increases in renin secretion, vasopressin secretion, and heart rate during arterial hypotension in rats....

  20. Naloxone : actions of an antagonist

    NARCIS (Netherlands)

    Dorp, Eveline Louise Arianna van

    2009-01-01

    The opioid antagonist naloxone has a special place in pharmacology – it has no intrinsic action of its own, but it is able to save lives in the case of life threatening side-effects caused by other drugs. Naloxone is an antagonist for all opioid receptors, but most specifically for the μ-opioid

  1. Viral Inhibition of the IFN-Induced JAK/STAT Signalling Pathway: Development of Live Attenuated Vaccines by Mutation of Viral-Encoded IFN-Antagonists

    Directory of Open Access Journals (Sweden)

    Stephen B. Fleming

    2016-06-01

    Full Text Available The interferon (IFN induced anti-viral response is amongst the earliest and most potent of the innate responses to fight viral infection. The induction of the Janus kinase/signal transducer and activation of transcription (JAK/STAT signalling pathway by IFNs leads to the upregulation of hundreds of interferon stimulated genes (ISGs for which, many have the ability to rapidly kill viruses within infected cells. During the long course of evolution, viruses have evolved an extraordinary range of strategies to counteract the host immune responses in particular by targeting the JAK/STAT signalling pathway. Understanding how the IFN system is inhibited has provided critical insights into viral virulence and pathogenesis. Moreover, identification of factors encoded by viruses that modulate the JAK/STAT pathway has opened up opportunities to create new anti-viral drugs and rationally attenuated new generation vaccines, particularly for RNA viruses, by reverse genetics.

  2. The improvement effects of edible bird’s nest on proliferation and activation of B lymphocyte and its antagonistic effects on immunosuppression induced by cyclophosphamide

    Directory of Open Access Journals (Sweden)

    Zhao R

    2016-01-01

    Full Text Available Ran Zhao,1,* Geng Li,1,* Xiu-juan Kong,1 Xiu-yan Huang,2 Wei Li,1 Yao-ying Zeng,2 Xiao-ping Lai31Traditional Chinese Medicinal College, Guangzhou University of Chinese Medicine, 2Life Science College, Jinan University, Guangzhou, 3Dongguan Mathematical Engineering Academy of Chinese Medicine, Guangzhou University of Chinese Medicine, Dongguan, People’s Republic of China*These authors contributed equally to this workAbstract: Edible bird’s nest (EBN is regarded as an immune-enhancing food in the People’s Republic of China. The aim of this study is to demonstrate the efficiency of EBN in improving the immunity of mouse both in vivo and in vitro. We observed the effects of EBN on spleen lymphocytes proliferation and activation, as well as immunoglobulin isotypes as indicators. In addition, we evaluated the content of total sIgA in the intestinal juice to assess mucosal immunity. The results showed that EBN could promote the proliferation and activation of B-cells and increase IgE, IgA, IgM, and IgG3 levels. We also found that EBN extract can promote the secretion of sIgA in the small intestine. Using cyclophosphamide (CY, we established an immunosuppressed mouse model in which we identified a reversal influence on the ratio of CD3+/CD19+ cells, which indicates that EBN also protects B-cells from the damage induced by CY. We also applied polymyxin B to exclude the interference of lipopolysaccharide throughout the experiment. In conclusion, we found that EBN can reduce the intestinal immune injury induced by CY by accelerating the proliferation and activation of B-cells and enhancing antibody secretion of B-cells.Keywords: chemotherapy, immunological enhancement, intestinal mucosal immune, EBN

  3. Early Illustrations of Geste Antagoniste in Cervical and Generalized Dystonia

    Directory of Open Access Journals (Sweden)

    Emmanuel Broussolle

    2015-09-01

    Full Text Available Background: Geste antagoniste, or sensory trick, is a voluntary maneuver that temporarily reduces the severity of dystonic postures or movements. We present a historical review of early reports and illustrations of geste antagoniste.Results: In 1894, Brissaud described this phenomenon in Paris in patients with torticollis. He noted that a violent muscular contraction could be reversed by a minor voluntary action. He considered the improvement obtained by what he called “simple mannerisms, childish behaviour or fake pathological movements” was proof of the psychogenic origin of what he named mental torticollis. This concept was supported by photographical illustrations of the patients. The term geste antagoniste was used by Brissaud’s pupils, Meige and Feindel, in their 1902 monograph on movement disorders. Other reports and illustrations of this sign were published in Europe between 1894 and 1906. Although not mentioned explicitly, geste antagoniste was also illustrated in a case report of generalized dystonia in Oppenheim’s 1911 seminal description of dystonia musculorum deformans in Berlin.Discussion: Brissaud-Meige’s misinterpretation of the geste antagoniste unfortunately anchored the psychogenic origin of dystonia for decades. In New York, Herz brought dystonia back into the realm of organic neurology in 1944. Thereafter, it was given prominence by other authors, notably Fahn and Marsden in the 1970–1980s. Nowadays, neurologists routinely investigate for geste antagoniste when a dystonic syndrome is suspected, because it provides a further argument in favor of dystonia. The term alleviating maneuver was proposed in 2014 to replace sensory trick or geste antagoniste. This major sign is now part of the motor phenomenology of the 2013 Movement Disorder Society’s classification of dystonia.

  4. Cannabinoid receptor antagonists: pharmacological opportunities, clinical experience, and translational prognosis.

    Science.gov (United States)

    Janero, David R; Makriyannis, Alexandros

    2009-03-01

    The endogenous cannabinoid (CB) (endocannabinoid) signaling system is involved in a variety of (patho)physiological processes, primarily by virtue of natural, arachidonic acid-derived lipids (endocannabinoids) that activate G protein-coupled CB1 and CB2 receptors. A hyperactive endocannabinoid system appears to contribute to the etiology of several disease states that constitute significant global threats to human health. Consequently, mounting interest surrounds the design and profiling of receptor-targeted CB antagonists as pharmacotherapeutics that attenuate endocannabinoid transmission for salutary gain. Experimental and clinical evidence supports the therapeutic potential of CB1 receptor antagonists to treat overweight/obesity, obesity-related cardiometabolic disorders, and substance abuse. Laboratory data suggest that CB2 receptor antagonists might be effective immunomodulatory and, perhaps, anti-inflammatory drugs. One CB1 receptor antagonist/inverse agonist, rimonabant, has emerged as the first-in-class drug approved outside the United States for weight control. Select follow-on agents (taranabant, otenabant, surinabant, rosonabant, SLV-319, AVE1625, V24343) have also been studied in the clinic. However, rimonabant's market withdrawal in the European Union and suspension of rimonabant's, taranabant's, and otenabant's ongoing development programs have highlighted some adverse clinical side effects (especially nausea and psychiatric disturbances) of CB1 receptor antagonists/inverse agonists. Novel CB1 receptor ligands that are peripherally directed and/or exhibit neutral antagonism (the latter not affecting constitutive CB1 receptor signaling) may optimize the benefits of CB1 receptor antagonists while minimizing any risk. Indeed, CB1 receptor-neutral antagonists appear from preclinical data to offer efficacy comparable to or better than that of prototype CB1 receptor antagonists/inverse agonists, with less propensity to induce nausea. Continued

  5. Olanzapine-Based Triple Regimens Versus Neurokinin-1 Receptor Antagonist-Based Triple Regimens in Preventing Chemotherapy-Induced Nausea and Vomiting Associated with Highly Emetogenic Chemotherapy: A Network Meta-Analysis.

    Science.gov (United States)

    Zhang, Zhonghan; Zhang, Yaxiong; Chen, Gang; Hong, Shaodong; Yang, Yunpeng; Fang, Wenfeng; Luo, Fan; Chen, Xi; Ma, Yuxiang; Zhao, Yuanyuan; Zhan, Jianhua; Xue, Cong; Hou, Xue; Zhou, Ting; Ma, Shuxiang; Gao, Fangfang; Huang, Yan; Chen, Likun; Zhou, Ningning; Zhao, Hongyun; Zhang, Li

    2018-01-12

    The current antiemetic prophylaxis for patients treated with highly emetogenic chemotherapy (HEC) included the olanzapine-based triplet and neurokinin-1 receptor antagonists (NK-1RAs)-based triplet. However, which one shows better antiemetic effect remained unclear. We systematically reviewed 43 trials, involving 16,609 patients with HEC, which compared the following antiemetics at therapeutic dose range for the treatment of chemotherapy-induced nausea and vomiting: olanzapine, aprepitant, casopitant, fosaprepitant, netupitant, and rolapitant. The main outcomes were the proportion of patients who achieved no nausea, complete response (CR), and drug-related adverse events. A Bayesian network meta-analysis was performed. Olanzapine-based triple regimens showed significantly better no-nausea rate in overall phase and delayed phase than aprepitant-based triplet (odds ratios 3.18, 3.00, respectively), casopitant-based triplet (3.78, 4.12, respectively), fosaprepitant-based triplet (3.08, 4.10, respectively), rolapitant-based triplet (3.45, 3.20, respectively), and conventional duplex regimens (4.66, 4.38, respectively). CRs of olanzapine-based triplet were roughly equal to different NK-1RAs-based triplet but better than the conventional duplet. Moreover, no significant drug-related adverse events were observed in olanzapine-based triple regimens when compared with NK-1RAs-based triple regimens and duplex regimens. Additionally, the costs of olanzapine-based regimens were obviously much lower than the NK-1RA-based regimens. Olanzapine-based triplet stood out in terms of nausea control and drug price but represented no significant difference of CRs in comparison with NK-1RAs-based triplet. Olanzapine-based triple regimens should be an optional antiemetic choice for patients with HEC, especially those suffering from delayed phase nausea. According to the results of this study, olanzapine-based triple antiemetic regimens were superior in both overall and delayed

  6. When and why are reliable organizations favored?

    DEFF Research Database (Denmark)

    Ethiraj, Sendil; Yi, Sangyoon

    of the ensuing work examined only corollary implications of this observation. We treat the observation as a research question and ask: when and why are reliable organizations favored by evolutionary forces? Using a simple theoretical model, we direct attention at a minimal set of variables that are implicated...... a representation of reality. Thus, our attempt is best characterized as shining a spotlight on a small part of the larger canvas that constitutes the literature on organizational change....

  7. Effect of H4R antagonist N-(2-aminoethyl)-5-chloro-1H-indol-2-carboxamides and 5-chloro-2-(piperazin-1-ylmethyl)-1H-benzimidazole on histamine and 4-methylhistamine-induced mast cell response.

    Science.gov (United States)

    Nagarajan, Gomathi; Mariappanadar, Vairamani; Tamizh, Muthu; Kaliappan, Ilango; Elden, Berla Thangam

    2017-06-01

    The histamine plays a decisive role in acute and chronic inflammatory responses and is regulated through its four types of distinct receptors designated from H1 to H4. Recently histamine 4 receptor (H4R) antagonists have been reported to possess various pharmacological effects against various allergic diseases. To investigate the inhibitory effect of N-(2-aminoethyl)-5-chloro-1H-indol-2-carboxamide (Compound A) and 5-chloro-2-(piperazin-1-ylmethyl)-1H-benzimidazole (Compound L) on H4R-mediated calcium mobilization, cytokine IL-13 production, ERK1/2, Akt and NF-κB activation in human mastocytoma cells-1 (HMC-1). Compounds A and L were synthesized chemically and their inhibitory effect on intracellular calcium release was analyzed by Fluo-4 calcium assay, cytokine measurement through ELISA and activation of signaling molecules by western blot. Pre-treatment with compounds A and L significantly reduced the H4R-mediated intracellular calcium release. Histamine and 4-methylhistamine (4-MH) induced Th2 cytokine IL-13 production in HMC-1 cells, was inhibited by compound A (77.61%, 74.25% at 1 μM concentration) and compound L (79.63%, 81.70% at 1 μM concentration). Furthermore, histamine induced the phosphorylation of ERK1/2, Akt and NF-κB was suppressed by compounds A and L at varying levels, ERK1/2 (88%, 86%), Akt (88%, 89%) and NF-κB (89%, 87%) in HMC-1 cells. Taken together these data demonstrate that compound A and compound L may block H4R-mediated downstream signaling events.

  8. A role for b-cell-depleting agents in treating psoriatic skin lesions induced by tumor necrosis factor-alpha antagonists: A case report and literature review

    Directory of Open Access Journals (Sweden)

    Ancuta Codrina Mihaela

    2014-01-01

    Full Text Available Despite recent advances in understanding the pathological pathways, clinical pattern and management opportunities for new-onset psoriasis as a paradoxical adverse event in patients receiving TNF inhibitors for their immune-mediated disorder, there is a subset of patients who are either partial responders or non-responders, whatever the therapeutic scenario. We present the case of new-onset psoriasis and severe alopecia development in a case study of long-standing rheumatoid arthritis (RA treated with adalimumab (ADA and leflunomide. Since skin lesions and alopecia are resistant to the classic protocol (topical treatment, ADA discontinuation and RA becomes highly active, rituximab (RTX was started. Dramatic improvement in joint disease, total remission of alopecia and partial remission of pustular psoriasis were described after the first RTX cycle. Although B-cell-depleting agents result in controversial effects on psoriatic skin lesions, this is the first case of ADA-induced psoriasis and alopecia that improved under RTX, suggesting a possible role in treating such a patient population.

  9. Efficacy of a Novel Sigma-1 Receptor Antagonist for Oxaliplatin-Induced Neuropathy: A Randomized, Double-Blind, Placebo-Controlled Phase IIa Clinical Trial.

    Science.gov (United States)

    Bruna, Jordi; Videla, Sebastián; Argyriou, Andreas A; Velasco, Roser; Villoria, Jesús; Santos, Cristina; Nadal, Cristina; Cavaletti, Guido; Alberti, Paola; Briani, Chiara; Kalofonos, Haralabos P; Cortinovis, Diego; Sust, Mariano; Vaqué, Anna; Klein, Thomas; Plata-Salamán, Carlos

    2018-01-01

    This trial assessed the efficacy of MR309 (a novel selective sigma-1 receptor ligand previously developed as E-52862) in ameliorating oxaliplatin-induced peripheral neuropathy (oxaipn). A discontinuous regimen of MR309 (400 mg/day, 5 days per cycle) was tested in patients with colorectal cancer receiving FOLFOX in a phase II, randomized, double-blind, placebo-controlled, multicenter clinical trial. Outcome measures included changes in 24-week quantitative measures of thermal sensitivity and total neuropathy score. In total, 124 patients were randomized (1:1) to MR309 or placebo. Sixty-three (50.8%) patients withdrew prematurely before completing 12 planned oxaliplatin cycles. Premature withdrawal because of cancer progression was less frequent in the MR309 group (7.4% vs 25.0% with placebo; p = 0.054). MR309 significantly reduced cold pain threshold temperature [mean treatment effect difference (SE) vs placebo: 5.29 (1.60)°C; p = 0.001] and suprathreshold cold stimulus-evoked pain intensity [mean treatment effect difference: 1.24 (0.57) points; p = 0.032]. Total neuropathy score, health-related quality-of-life measures, and nerve-conduction parameters changed similarly in both arms, whereas the proportion of patients with severe chronic neuropathy (National Cancer Institute Common Terminology Criteria for Adverse Events ≥ 3) was significantly lower in the MR309 group (3.0% vs 18.2% with placebo; p = 0.046). The total amount of oxaliplatin delivered was greater in the active arm (1618.9 mg vs 1453.8 mg with placebo; p = 0.049). Overall, 19.0% of patients experienced at least 1 treatment-related adverse event (25.8% and 11.9% with MR309 and placebo, respectively). Intermittent treatment with MR309 was associated with reduced acute oxaipn and higher oxaliplatin exposure, and showed a potential neuroprotective role for chronic cumulative oxaipn. Furthermore, MR309 showed an acceptable safety profile.

  10. Studies on antagonistic marine streptomycetes

    Digital Repository Service at National Institute of Oceanography (India)

    Chandramohan, D.; Nair, S.

    Sixty nine strains of Streptomyces sp. isolated from the sediments of Andaman and Nicobar islands (Bay of Bengal) were screened for their antagonistic property against a number of test cultures (Vibrio sp., Klebsiella sp., Escherichia coli, Shigella...

  11. Catalytically favorable surface patterns in Pt-Au nanoclusters

    KAUST Repository

    Mokkath, Junais Habeeb

    2013-01-01

    Motivated by recent experimental demonstrations of novel PtAu nanoparticles with highly enhanced catalytic properties, we present a systematic theoretical study that explores principal catalytic indicators as a function of the particle size and composition. We find that Pt electronic states in the vicinity of the Fermi level combined with a modified electron distribution in the nanoparticle due to Pt-to-Au charge transfer are the origin of the outstanding catalytic properties. From our model we deduce the catalytically favorable surface patterns that induce ensemble and ligand effects. © The Royal Society of Chemistry 2013.

  12. Differential and additive suppressive effects of 5-HT3 (palonosetron)- and NK1 (netupitant)-receptor antagonists on cisplatin-induced vomiting and ERK1/2, PKA and PKC activation.

    Science.gov (United States)

    Darmani, Nissar A; Zhong, Weixia; Chebolu, Seetha; Mercadante, Frank

    2015-04-01

    To better understand the anti-emetic profile of the 5-HT3 (palonosetron)- and the tachykinin NK1 (netupitant) -receptor antagonists, either alone or in combination, we evaluated the effects of palonosetron and/or netupitant pretreatment on cisplatin-evoked vomiting and changes in the phosphorylation of brainstem kinases such as the extracellular signal-regulated protein kinases 1 and 2 (ERK1/2), protein kinase C alpha/beta (PKCα/β), and protein kinase A (PKA) in the least shrew. Our results demonstrate that cisplatin (10mg/kg, i.p.) causes emesis in the least shrew over 40h with respective peak early- and delayed-phases occurring at 1 - 2 and 32 - 34h post-injection. During the early phase (0 - 16h post cisplatin), palonosetron (0.1mg/kg, s.c.) significantly protected shrews from vomiting with a near complete suppression of vomit frequency. Palonosetron also significantly protected shrews from vomiting during the delayed phase (27 - 40h post cisplatin), but the reduction in mean vomit frequency failed to achieve significance. On the other hand, netupitant (5mg/kg, i.p.) totally abolished vomiting during the delayed phase, and tended to suppress the mean vomit frequency during the acute phase. The combined treatment protected shrews almost completely from vomiting during both phases. Brainstem pERK1/2 levels were significantly elevated at all time-points except at 40h post-cisplatin administration. PKA phosphorylation tended to be elevated throughout the delayed phase, but a significant increase only occurred at 33h. Brainstem pPKCα/β levels were enhanced during acute-phase with a significant elevation at 2h. Palonosetron, netupitant or their combination had no effect on elevated pERK1/2 levels during acute phase, but the combination reversed ERK1/2 phosphorylation at 33h post-cisplatin treatment. In addition, only the combined regimen prevented the cisplatin-induced PKCα/β phosphorylation observed at the acute phase. On the other hand, palonosetron and

  13. Respiratory Syncytial Virus Fusion Protein-Induced Toll-Like Receptor 4 (TLR4) Signaling Is Inhibited by the TLR4 Antagonists Rhodobacter sphaeroides Lipopolysaccharide and Eritoran (E5564) and Requires Direct Interaction with MD-2

    Science.gov (United States)

    Rallabhandi, Prasad; Phillips, Rachel L.; Boukhvalova, Marina S.; Pletneva, Lioubov M.; Shirey, Kari Ann; Gioannini, Theresa L.; Weiss, Jerrold P.; Chow, Jesse C.; Hawkins, Lynn D.; Vogel, Stefanie N.; Blanco, Jorge C. G.

    2012-01-01

    ABSTRACT Respiratory syncytial virus (RSV) is a leading cause of infant mortality worldwide. Toll-like receptor 4 (TLR4), a signaling receptor for structurally diverse microbe-associated molecular patterns, is activated by the RSV fusion (F) protein and by bacterial lipopolysaccharide (LPS) in a CD14-dependent manner. TLR4 signaling by LPS also requires the presence of an additional protein, MD-2. Thus, it is possible that F protein-mediated TLR4 activation relies on MD-2 as well, although this hypothesis has not been formally tested. LPS-free RSV F protein was found to activate NF-κB in HEK293T transfectants that express wild-type (WT) TLR4 and CD14, but only when MD-2 was coexpressed. These findings were confirmed by measuring F-protein-induced interleukin 1β (IL-1β) mRNA in WT versus MD-2−/− macrophages, where MD-2−/− macrophages failed to show IL-1β expression upon F-protein treatment, in contrast to the WT. Both Rhodobacter sphaeroides LPS and synthetic E5564 (eritoran), LPS antagonists that inhibit TLR4 signaling by binding a hydrophobic pocket in MD-2, significantly reduced RSV F-protein-mediated TLR4 activity in HEK293T-TLR4–CD14–MD-2 transfectants in a dose-dependent manner, while TLR4-independent NF-κB activation by tumor necrosis factor alpha (TNF-α) was unaffected. In vitro coimmunoprecipitation studies confirmed a physical interaction between native RSV F protein and MD-2. Further, we demonstrated that the N-terminal domain of the F1 segment of RSV F protein interacts with MD-2. These data provide new insights into the importance of MD-2 in RSV F-protein-mediated TLR4 activation. Thus, targeting the interaction between MD-2 and RSV F protein may potentially lead to novel therapeutic approaches to help control RSV-induced inflammation and pathology. PMID:22872782

  14. Attenuation of cold stress-induced exacerbation of cardiac and adipose tissue pathology and metabolic disorders in a rat model of metabolic syndrome by the glucocorticoid receptor antagonist RU486.

    Science.gov (United States)

    Nagasawa, K; Matsuura, N; Takeshita, Y; Ito, S; Sano, Y; Yamada, Y; Uchinaka, A; Murohara, T; Nagata, K

    2016-04-25

    Chronic stress affects the central nervous system as well as endocrine, metabolic and immune systems. However, the effects of cold stress on cardiovascular and metabolic disorders in metabolic syndrome (MetS) have remained unclear. We recently characterized DahlS.Z-Lepr(fa)/Lepr(fa) (DS/obese) rats, derived from a cross between Dahl salt-sensitive and Zucker rats, as a new animal model of MetS. We have now investigated the effects of chronic cold stress and glucocorticoid receptor (GR) blockade on cardiac and adipose tissue pathology as well as on metabolic parameters in this model. DS/obese rats were exposed to cold stress (immersion in ice-cold water to a depth of 1-2 cm for 2 h per day) with or without subcutaneous injection of the GR antagonist RU486 (2 mg kg(-1)day(-1)) for 4 weeks beginning at 9 weeks of age. Age-matched homozygous lean (DahlS.Z-Lepr(+)/Lepr(+)) littermates served as a control. Chronic cold stress exacerbated hypertension as well as left ventricular (LV) hypertrophy, fibrosis and diastolic dysfunction in DS/obese rats in a manner sensitive to RU486 treatment. Cold stress with or without RU486 did not affect body weight or fat mass. In contrast, cold stress further increased cardiac oxidative stress as well as macrophage infiltration and proinflammatory gene expression in LV and visceral fat tissue, with all of these effects being attenuated by RU486. Cold stress also further increased GR and 11β-hydroxysteroid dehydrogenase type 1 mRNA and protein abundance in LV and visceral adipose tissue, and these effects were again inhibited by RU486. In addition, RU486 ameliorated the stress-induced aggravation of dyslipidemia, glucose intolerance and insulin resistance in DS/obese rats. Our results implicate GR signaling in cold stress-induced exacerbation of cardiac and adipose tissue pathology as well as of abnormal glucose and lipid metabolism in a rat model of MetS.

  15. Effects of ionotropic glutamate receptor antagonists on rat dural artery diameter in an intravital microscopy model

    DEFF Research Database (Denmark)

    Chan, K Y; Gupta, S; de Vries, R

    2010-01-01

    studies have shown that glutamate receptor antagonists affect the pathophysiology of migraine. This study investigated whether antagonists of NMDA (ketamine and MK801), AMPA (GYKI52466) and kainate (LY466195) glutamate receptors affected dural vasodilatation induced by alpha-CGRP, capsaicin...

  16. Bronchoprotection with a leukotriene receptor antagonist in asthmatic preschool children

    DEFF Research Database (Denmark)

    Bisgaard, H; Nielsen, K G

    2000-01-01

    We hypothesized that a leukotriene receptor antagonist (LTRA) could provide bronchoprotection against the cold, dry air-induced response in asthmatic preschool children. In a randomized, double-blind, placebo-controlled crossover study, we examined the effect of the specific LTRA montelukast at 5...

  17. Sympatho-inhibitory properties of various AT1 receptor antagonists

    NARCIS (Netherlands)

    Balt, Jippe C.; Mathy, Marie-Jeanne; Pfaffendorf, Martin; van Zwieten, Peter A.

    2002-01-01

    It is well known that angiotensin II (Ang II) can facilitate the effects of sympathetic neurotransmission. In the present study, using various experimental models, we investigated the inhibitory effects of several Ang II subtype 1 receptor (AT1) antagonists on this Ang II-induced facilitation. We

  18. Contrasting effects of intralocus sexual conflict on sexually antagonistic coevolution

    NARCIS (Netherlands)

    Pennell, Tanya M; de Haas, Freek J H; Morrow, Edward H; van Doorn, G Sander

    2016-01-01

    Evolutionary conflict between the sexes can induce arms races in which males evolve traits that are detrimental to the fitness of their female partners, and vice versa. This interlocus sexual conflict (IRSC) has been proposed as a cause of perpetual intersexual antagonistic coevolution with

  19. The Effect of Sympathetic Antagonists on the Antidepressant Action ...

    African Journals Online (AJOL)

    Alprazolam is an anti-anxiety drug shown to be effective in the treatment of depression. In this study, the effect of sympathetic receptor antagonists on alprazolam–induced antidepressant action was studied using a mouse model of forced swimming behavioral despair. The interaction of three sympathetic receptor ...

  20. The Attractiveness of Opposites: Agonists and Antagonists.

    LENUS (Irish Health Repository)

    O'Brien, Tony

    2015-02-02

    ABSTRACT Opioid-induced bowel dysfunction, of which constipation is the most common aspect, is a major limiting factor in the use of opioids for pain management. The availability of an oral, long-acting formulation of oxycodone and naloxone represents a highly significant development in pain management. The combination of an opioid analgesic with an opioid antagonist offers reliable pain control with a significant reduction in the burden of opioid-induced constipation. This report is adapted from paineurope 2014; Issue 3, ©Haymarket Medical Publications Ltd, and is presented with permission. paineurope is provided as a service to pain management by Mundipharma International, LTD and is distributed free of charge to healthcare professionals in Europe. Archival issues can be accessed via the website: http:\\/\\/www.paineurope.com at which European health professionals can register online to receive copies of the quarterly publication.

  1. Appeals court reverses verdict favoring drug companies.

    Science.gov (United States)

    1995-06-02

    An appeals court reversed a verdict favoring drug companies after the widow of a hemophiliac, whose death was linked to HIV-tainted blood products, sued four pharmaceutical companies to pay damages. The four companies, Alpha Therapeutic Corp., Miles Laboratories Inc., Armour Pharmaceutical Co., and Baxter Travenol Laboratories Inc., provided Factor VIII, a clotting concentrate, to [name removed] [name removed], the plaintiff's husband, from 1972 until his death in 1987. [Name removed]'s wife sued the companies, alleging that the defendants negligently solicited blood plasma from paid donors who had a high risk of having HIV, failed to determine whether any lots of Factor VIII contained plasma from an at-risk donor, failed to warn consumers of possible risks, and failed to heat-treat HIV and other viruses in Factor VIII, despite industry-wide knowledge of the risk of infection. The three-judge panel said the trial judge's decision to avoid ruling on the antigenic stimulation theory, based on insufficient evidence, was improper. In addition, the appeals court said a retrial is necessary because of improper remarks made by Alpha's attorney.

  2. Children's need for favorable acoustics in schools

    Science.gov (United States)

    Nelson, Peggy B.

    2003-10-01

    Children continue to improve their understanding of speech in noise and reverberation throughout childhood and adolescence. They do not typically achieve adult performance levels until their late teenage years. As a result, schools that are designed to be acoustically adequate for adult understanding may be insufficient for full understanding by young children. In addition, children with hearing loss, those with attention problems, and those learning in a non-native language require even more favorable signal-to-noise ratios. This tutorial will review the literature gathered by the ANSl/ASA working group on classroom acoustics that shaped the recommendations of the working group. Special topics will include speech perception data from typically developing infants and children, from children with hearing loss, and from adults and children listening in a non-native language. In addition, the tutorial will overview recommendations contained within ANSI standard 12.60-2002: Acoustical Performance Criteria, Design Requirements, and Guidelines for Schools. The discussion will also include issues related to designing quiet classrooms and working with local schools and professionals.

  3. Interleukin-1-receptor antagonist in type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Larsen, Claus M; Faulenbach, Mirjam; Vaag, Allan

    2007-01-01

    BACKGROUND: The expression of interleukin-1-receptor antagonist is reduced in pancreatic islets of patients with type 2 diabetes mellitus, and high glucose concentrations induce the production of interleukin-1beta in human pancreatic beta cells, leading to impaired insulin secretion, decreased cell...... proliferation, and apoptosis. METHODS: In this double-blind, parallel-group trial involving 70 patients with type 2 diabetes, we randomly assigned 34 patients to receive 100 mg of anakinra (a recombinant human interleukin-1-receptor antagonist) subcutaneously once daily for 13 weeks and 36 patients to receive...

  4. Excitatory amino acid receptor antagonists

    DEFF Research Database (Denmark)

    Johansen, T N; Frydenvang, Karla Andrea; Ebert, B

    1997-01-01

    We have previously shown that (RS)-2-amino-2-(5-tert-butyl-3-hydroxyisoxazol-4-yl)acetic acid (ATAA) is an antagonist at N-methyl-D-aspartic acid (NMDA) and (RS)-2-amino-3-(3-hydroxy-5-methylisoxazol-4-yl)propionic acid (AMPA) receptors. We have now resolved ATAA via diastereomeric salt formation...

  5. ANTAGONISTIC POTENTIAL OF FLUORESCENT Pseudomonas ...

    African Journals Online (AJOL)

    Prof. Adipala Ekwamu

    This study focused on the antagonistic potential of fluorescent Pseudomonas in vitro, and its inoculation effect on growth performance of Lycopersicon esculentum in Fusarium oxysporum and Rhizoctonia solani infested soil. Biochemical characteristics of fluorescent Pseudomonas showed that all ten isolates were positive ...

  6. Great Basin geologic framework and uranium favorability

    International Nuclear Information System (INIS)

    Larson, L.T.; Beal, L.H.

    1978-01-01

    Work on this report has been done by a team of seven investigators assisted over the project span by twenty-three undergraduate and graduate students from May 18, 1976 to August 19, 1977. The report is presented in one volume of text, one volume or Folio of Maps, and two volumes of bibliography. The bibliography contains approximately 5300 references on geologic subjects pertinent to the search for uranium in the Great Basin. Volume I of the bibliography lists articles by author alphabetically and Volume II cross-indexes these articles by location and key word. Chapters I through IV of the Text volume and accompanying Folio Map Sets 1, 2, 3, 4, and 5, discuss the relationship of uranium to rock and structural environments which dominate the Great Basin. Chapter 5 and Map Sets 6 and 7 provide a geochemical association/metallogenic grouping of mineral occurrences in the Great Basin along with information on rock types hosting uranium. Chapter VI summarizes the results of a court house claim record search for 'new' claiming areas for uranium, and Chapter VII along with Folio Map Set 8 gives all published geochronological data available through April 1, 1977 on rocks of the Great Basin. Chapter VIII provides an introduction to a computer analysis of characteristics of certain major uranium deposits in crystalline rocks (worldwide) and is offered as a suggestion of what might be done with uranium in all geologic environments. We believe such analysis will assist materially in constructing exploration models. Chapter IX summarizes criteria used and conclusions reached as to the favorability of uranium environments which we believe to exist in the Great Basin and concludes with recommendations for both exploration and future research. A general summary conclusion is that there are several geologic environments within the Great Basin which have considerable potential and that few, if any, have been sufficiently tested

  7. Antiallergic effects of H1-receptor antagonists.

    Science.gov (United States)

    Baroody, F M; Naclerio, R M

    2000-01-01

    The primary mechanism of antihistamine action in the treatment of allergic diseases is believed to be competitive antagonism of histamine binding to cellular receptors (specifically, the H1-receptors), which are present on nerve endings, smooth muscles, and glandular cells. This notion is supported by the fact that structurally unrelated drugs antagonize the H1-receptor and provide clinical benefit. However, H1-receptor antagonism may not be their sole mechanism of action in treating allergic rhinitis. On the basis of in vitro and animal experiments, drugs classified as H1-receptor antagonists have long been recognized to have additional pharmacological properties. Most first-generation H1-antihistamines have anticholinergic, sedative, local anaesthetic, and anti-5-HT effects, which might favourably affect the symptoms of the allergic response but also contribute to side-effects. These additional properties are not uniformly distributed among drugs classified as H1-receptor antagonists. Azatadine, for example, inhibits in vitro IgE-mediated histamine and leukotriene (LT) release from mast cells and basophils. In human challenge models, terfenadine, azatadine, and loratadine reduce IgE-mediated histamine release. Cetirizine reduces eosinophilic infiltration at the site of antigen challenge in the skin, but not the nose. In a nasal antigen challenge model, cetirizine pretreatment did not affect the levels of histamine and prostaglandin D2 recovered in postchallenge lavages, whereas the levels of albumin, N-tosyl-L-arginine methyl ester (TAME) esterase activity, and LTs were reduced. Terfenadine, cetirizine, and loratadine blocked allergen-induced hyperresponsiveness to methacholine. In view of the complexity of the pathophysiology of allergy, a number of H1 antagonists with additional properties are currently under development for allergic diseases. Mizolastine, a new H1-receptor antagonist, has been shown to have additional actions that should help reduce the

  8. Histamine-2 receptor antagonists as immunomodulators: new therapeutic views?

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen

    1996-01-01

    of proliferation and angiogenesis. Specific histamine receptors have been identified on the surface of bone marrow cells, immune competent cells, endothelial cells, fibroblasts, and also on malignant cells. This has prompted research in regulation by specific histamine receptor agonists and antagonists. Results...... from such studies are currently accumulating and suggest that the histamine-2 receptor antagonists have potential beneficial effects in the treatment of certain malignant, autoimmune and skin diseases, either alone or in combination with other drugs. The beneficial effect of histamine-2 receptor...... antagonists as adjuvant single drugs to reduce trauma-, blood transfusion- and sepsis-induced immunosuppression has led to research in combined treatment regimens in major surgery, particularly, of patients operated on for malignant diseases....

  9. Cyclic benzamidines as orally efficacious NR2B-selective NMDA receptor antagonists.

    Science.gov (United States)

    Nguyen, Kevin T; Claiborne, Christopher F; McCauley, John A; Libby, Brian E; Claremon, David A; Bednar, Rodney A; Mosser, Scott D; Gaul, Stanley L; Connolly, Thomas M; Condra, Cindra L; Bednar, Bohumil; Stump, Gary L; Lynch, Joseph J; Koblan, Kenneth S; Liverton, Nigel J

    2007-07-15

    A novel series of cyclic benzamidines was synthesized and shown to exhibit NR2B-subtype selective NMDA antagonist activity. Compound 29 is orally active in a carrageenan-induced rat hyperalgesia model of pain.

  10. Effects of the benzodiazepine receptor antagonist flumazenil in hepatic encephalopathy in humans.

    Science.gov (United States)

    Bansky, G; Meier, P J; Riederer, E; Walser, H; Ziegler, W H; Schmid, M

    1989-09-01

    If increased gamma-aminobutyric acid (GABA)-mediated neurotransmission contributes to the mediation of hepatic encephalopathy, it may be possible to induce ameliorations of the syndrome by pharmacologically antagonizing a component of the GABA/benzodiazepine receptor complex. To test this possibility we administered the benzodiazepine receptor antagonist flumazenil by intravenous injection to 14 patients with hepatic encephalopathy complicating cirrhosis. Flumazenil administration induced variable and transient, but distinct, improvements of the mental status in 71% of the patients. The degree of encephalopathy improved from stage IV to stage II in 4 patients and from stage IV to stage III in 2 patients. The mental status of all patients with less advanced encephalopathy (3 with stage III, 1 with stage II) also improved, but these responses were clinically less impressive. The arousal effect occurred within minutes after the injection and lasted for 1 to 2 h. Furthermore, it was associated with a significant increase of the mean electroencephalographic frequency from 4.2 to 5.2 cycle/s. Of the 8 patients who were ultimately discharged from the hospital, 7 had responded to flumazenil. No patient who died within 48 h of receiving flumazenil had shown any arousal effect. These findings strongly favor a prominent pathogenetic role of increased GABAergic tone in hepatic encephalopathy in humans and suggest that a positive response to flumazenil might be of prognostic value in predicting short-term survival in encephalopathic patients with liver disease.

  11. Reduced solar activity favors twin maternities.

    Science.gov (United States)

    Melnikov, Vladimir N

    2012-02-01

    Mechanisms underlying effects of physical factors on twin births are unclear. The present work studied an association between monthly and yearly multiple birth rates (MBRs) in the Novosibirsk region, south-west Siberia, in relation to solar activity (sunspot numbers) and geomagnetic activity (Ap index) from 1957 to 2008. The difference was verified by comparing the yearly MBR observed in 3-year peaks (M = 7.36, SD = 0.33 per 1,000 births) and 3-year troughs (M = 8.10, SD = 0.31 per 1,000 births, p twin maternities. The results show that elevated solar activity within the 11-year cycle coinciding with the time of conception inhibits multiple births in a manner depending on geomagnetic activity. It is hypothesized that the likely mechanism underlying the association is early fetal loss induced by solar radiation/flux and its terrestrial mediators.

  12. Calcium antagonists and the diabetic hypertensive patient

    DEFF Research Database (Denmark)

    Parving, H H; Rossing, P

    1993-01-01

    reduces albuminuria, delays the progression of nephropathy, and postpones renal insufficiency in diabetic nephropathy. Calcium antagonists and angiotensin converting enzyme inhibitors induce an acute increase in the glomerular filtration rate, renal plasma flow, and renal sodium excretion......Roughly 40% of all diabetic patients, whether insulin dependent or not, develop persistent albuminuria (over 300 mg/24 hr), a decrease in the glomerular filtration rate, and elevated blood pressure, ie, diabetic nephropathy. Diabetic nephropathy is the single most important cause of end stage renal...... disease in the Western world, and accounts for over a quarter of all end stage renal disease. It also is a major cause of the increased morbidity and mortality seen in diabetic patients; for example, the cost of end stage renal care in the United States currently exceeds +1.8 billion per year for diabetic...

  13. 12 CFR 560.110 - Most favored lender usury preemption.

    Science.gov (United States)

    2010-01-01

    ... 12 Banks and Banking 5 2010-01-01 2010-01-01 false Most favored lender usury preemption. 560.110... INVESTMENT Lending and Investment Provisions Applicable to all Savings Associations § 560.110 Most favored... permits its most favored lender to charge late fees, then a savings association located in that state may...

  14. Clinical Development of Histamine H4Receptor Antagonists.

    Science.gov (United States)

    Thurmond, Robin L; Venable, Jennifer; Savall, Brad; La, David; Snook, Sandra; Dunford, Paul J; Edwards, James P

    2017-01-01

    The discovery of the histamine H 4 receptor (H 4 R) provided a new avenue for the exploration of the physiological role of histamine, as well as providing a new drug target for the development of novel antihistamines. The first step in this process was the identification of selective antagonists to help unravel the pharmacology of the H 4 R relative to other histamine receptors. The discovery of the selective H 4 R antagonist JNJ 7777120 was vital for showing a role for the H 4 R in inflammation and pruritus. While this compound has been very successful as a tool for understanding the function of the receptor, it has drawbacks, including a short in vivo half-life and hypoadrenocorticism toxicity in rats and dogs, that prevented advancing it into clinical studies. Further research let to the discovery of JNJ 39758979, which, similar to JNJ 7777120, was a potent and selective H 4 R antagonist and showed anti-inflammatory and anti-pruritic activity preclinically. JNJ 39758979 advanced into human clinical studies and showed efficacy in reducing experimental pruritus and in patients with atopic dermatitis. However, development of this compound was terminated due to the occurrence of drug-induced agranulocytosis. This was overcome by developing another H 4 R antagonist with a different chemical structure, toreforant, that does not appear to have this side effect. Toreforant has been tested in clinical studies in patients with rheumatoid arthritis, asthma, or psoriasis. In conclusions there have been many H 4 R antagonists reported in the literature, but only a few have been studied in humans underscoring the difficulty in finding ligands with all of the properties necessary for testing in the clinic. Nevertheless, the clinical data to date suggests that H 4 R antagonists can be beneficial in treating atopic dermatitis and pruritus.

  15. The Role of α1-Adrenoceptor Antagonists in the Treatment of Prostate and Other Cancers

    Directory of Open Access Journals (Sweden)

    Mallory Batty

    2016-08-01

    Full Text Available This review evaluates the role of α-adrenoceptor antagonists as a potential treatment of prostate cancer (PCa. Cochrane, Google Scholar and Pubmed were accessed to retrieve sixty-two articles for analysis. In vitro studies demonstrate that doxazosin, prazosin and terazosin (quinazoline α-antagonists induce apoptosis, decrease cell growth, and proliferation in PC-3, LNCaP and DU-145 cell lines. Similarly, the piperazine based naftopidil induced cell cycle arrest and death in LNCaP-E9 cell lines. In contrast, sulphonamide based tamsulosin did not exhibit these effects. In vivo data was consistent with in vitro findings as the quinazoline based α-antagonists prevented angiogenesis and decreased tumour mass in mice models of PCa. Mechanistically the cytotoxic and antitumor effects of the α-antagonists appear largely independent of α 1-blockade. The proposed targets include: VEGF, EGFR, HER2/Neu, caspase 8/3, topoisomerase 1 and other mitochondrial apoptotic inducing factors. These cytotoxic effects could not be evaluated in human studies as prospective trial data is lacking. However, retrospective studies show a decreased incidence of PCa in males exposed to α-antagonists. As human data evaluating the use of α-antagonists as treatments are lacking; well designed, prospective clinical trials are needed to conclusively demonstrate the anticancer properties of quinazoline based α-antagonists in PCa and other cancers.

  16. Synthesis and testing of tetrodotoxin and batrachotoxin antagonists. Annual report, 1 February 1987-31 January 1988

    Energy Technology Data Exchange (ETDEWEB)

    Toll, L.

    1988-06-06

    Compounds have been designed and synthesized as potential antagonists to the neurotoxin batrachotoxin. The compounds synthesized to date have moderate to low affinity for the batrachotoxin binding site. Their potential as antagonists of batrachotoxin or veratridine-induced Na-flux in neuroblastoma cells is currently under investigation. The synthesis of analogs which should have increased affinity for the batrachotoxin binding site is continuing. We have also begun the synthesis of potential antagonists to the neurotoxin tetrodotoxin.

  17. A Natural CCR2 Antagonist Relieves Tumor-associated Macrophage-mediated Immunosuppression to Produce a Therapeutic Effect for Liver Cancer

    Directory of Open Access Journals (Sweden)

    Wenbo Yao

    2017-08-01

    Full Text Available Hepatocellular carcinoma (HCC is a common malignant tumor in the digestive tract with limited therapeutic choices. Although sorafenib, an orally administered multikinase inhibitor, has produced survival benefits for patients with advanced HCC, favorable clinical outcomes are limited due to individual differences and resistance. The application of immunotherapy, a promising approach for HCC is urgently needed. Macrophage infiltration, mediated by the CCL2/CCR2 axis, is a potential immunotherapeutic target. Here, we report that a natural product from Abies georgei, named 747 and related in structure to kaempferol, exhibits sensitivity and selectivity as a CCR2 antagonist. The specificity of 747 on CCR2 was demonstrated via calcium flux, the binding domain of CCR2 was identified in an extracellular loop by chimera binding assay, and in vivo antagonistic activity of 747 was confirmed through a thioglycollate-induced peritonitis model. In animals, 747 elevated the number of CD8+ T cells in tumors via blocking tumor-infiltrating macrophage-mediated immunosuppression and inhibited orthotopic and subcutaneous tumor growth in a CD8+ T cell-dependent manner. Further, 747 enhanced the therapeutic efficacy of low-dose sorafenib without obvious toxicity, through elevating the numbers of intra-tumoral CD8+ T cells and increasing death of tumor cells. Thus, we have discovered a natural CCR2 antagonist and have provided a new perspective on development of this antagonist for treatment of HCC. In mouse models of HCC, 747 enhanced the tumor immunosuppressive microenvironment and potentiated the therapeutic effect of sorafenib, indicating that the combination of an immunomodulator with a chemotherapeutic drug could be a new approach for treating HCC.

  18. Histamine-2 receptor antagonists as immunomodulators: new therapeutic views?

    DEFF Research Database (Denmark)

    Nielsen, Hans Jørgen

    1996-01-01

    Considerable evidence has emerged to suggest that histamine participates in the regulation of the inflammatory response, immune reaction, coagulation cascade, and cardiovascular function. Furthermore, histamine may play a major role in the growth of normal and malignant tissue as a regulator...... antagonists as adjuvant single drugs to reduce trauma-, blood transfusion- and sepsis-induced immunosuppression has led to research in combined treatment regimens in major surgery, particularly, of patients operated on for malignant diseases....

  19. Chitinolytic Enterobacter agglomerans Antagonistic to Fungal Plant Pathogens

    OpenAIRE

    Chernin, L.; Ismailov, Z.; Haran, S.; Chet, I.

    1995-01-01

    Three Enterobacter agglomerans strains which produce and excrete proteins with chitinolytic activity were found while screening soil-borne bacteria antagonistic to fungal plant pathogens. The chitinolytic activity was induced when the strains were grown in the presence of colloidal chitin as the sole carbon source. It was quantitated by using assays with chromogenic p-nitrophenyl analogs of disaccharide, trisaccharide, and tetrasaccharide derivatives of N-acetylglucosamine. A set of three flu...

  20. EndophyticTrichoderma gamsiiYIM PH30019: a promising biocontrol agent with hyperosmolar, mycoparasitism, and antagonistic activities of induced volatile organic compounds on root-rot pathogenic fungi ofPanax notoginseng.

    Science.gov (United States)

    Chen, Jin-Lian; Sun, Shi-Zhong; Miao, Cui-Ping; Wu, Kai; Chen, You-Wei; Xu, Li-Hua; Guan, Hui-Lin; Zhao, Li-Xing

    2016-10-01

    Biocontrol agents are regarded as promising and environmental friendly approaches as agrochemicals for phytodiseases that cause serious environmental and health problems. Trichoderma species have been widely used in suppression of soil-borne pathogens. In this study, an endophytic fungus, Trichoderma gamsii YIM PH30019, from healthy Panax notoginseng root was investigated for its biocontrol potential. In vitro detached healthy roots, and pot and field experiments were used to investigate the pathogenicity and biocontrol efficacy of T. gamsii YIM PH30019 to the host plant. The antagonistic mechanisms against test phytopathogens were analyzed using dual culture, scanning electron microscopy, and volatile organic compounds (VOCs). Tolerance to chemical fertilizers was also tested in a series of concentrations. The results indicated that T. gamsii YIM PH30019 was nonpathogenic to the host, presented appreciable biocontrol efficacy, and could tolerate chemical fertilizer concentrations of up to 20%. T. gamsii YIM PH30019 displayed antagonistic activities against the pathogenic fungi of P . notoginseng via production of VOCs. On the basis of gas chromatography-mass spectrometry, VOCs were identified as dimethyl disulfide, dibenzofuran, methanethiol, ketones, etc., which are effective ingredients for antagonistic activity. T. gamsii YIM PH30019 was able to improve the seedlings' emergence and protect P. notoginseng plants from soil-borne disease in the continuous cropping field tests. The results suggest that the endophytic fungus T. gamsii YIM PH30019 may have a good potential as a biological control agent against notoginseng phytodiseases and can provide a clue to further illuminate the interactions between Trichoderma and phytopathogens.

  1. Characterization of a novel non-steroidal glucocorticoid receptor antagonist

    International Nuclear Information System (INIS)

    Li, Qun-Yi; Zhang, Meng; Hallis, Tina M.; DeRosier, Therese A.; Yue, Jian-Min; Ye, Yang; Mais, Dale E.; Wang, Ming-Wei

    2010-01-01

    Selective antagonists of the glucocorticoid receptor (GR) are desirable for the treatment of hypercortisolemia associated with Cushing's syndrome, psychic depression, obesity, diabetes, neurodegenerative diseases, and glaucoma. NC3327, a non-steroidal small molecule with potent binding affinity to GR (K i = 13.2 nM), was identified in a high-throughput screening effort. As a full GR antagonist, NC3327 greatly inhibits the dexamethasone (Dex) induction of marker genes involved in hepatic gluconeogenesis, but has a minimal effect on matrix metalloproteinase 9 (MMP-9), a GR responsive pro-inflammatory gene. Interestingly, the compound recruits neither coactivators nor corepressors to the GR complex but competes with glucocorticoids for the interaction between GR and a coactivator peptide. Moreover, NC3327 does not trigger GR nuclear translocation, but significantly blocks Dex-induced GR transportation to the nucleus, and thus appears to be a 'competitive' GR antagonist. Therefore, the non-steroidal compound, NC3327, may represent a new class of GR antagonists as potential therapeutics for a variety of cortisol-related endocrine disorders.

  2. Characterization of a novel non-steroidal glucocorticoid receptor antagonist

    Energy Technology Data Exchange (ETDEWEB)

    Li, Qun-Yi; Zhang, Meng [The National Center for Drug Screening, Shanghai (China); State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (China); Hallis, Tina M.; DeRosier, Therese A. [Cell Systems Division, Invitrogen, Madison, WI (United States); Yue, Jian-Min; Ye, Yang [State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (China); Mais, Dale E. [The National Center for Drug Screening, Shanghai (China); MPI Research, Mattawan, MI (United States); Wang, Ming-Wei, E-mail: wangmw@mail.shcnc.ac.cn [The National Center for Drug Screening, Shanghai (China); State Key Laboratory of Drug Research, Shanghai Institute of Materia Medica, Chinese Academy of Sciences, Shanghai (China)

    2010-01-15

    Selective antagonists of the glucocorticoid receptor (GR) are desirable for the treatment of hypercortisolemia associated with Cushing's syndrome, psychic depression, obesity, diabetes, neurodegenerative diseases, and glaucoma. NC3327, a non-steroidal small molecule with potent binding affinity to GR (K{sub i} = 13.2 nM), was identified in a high-throughput screening effort. As a full GR antagonist, NC3327 greatly inhibits the dexamethasone (Dex) induction of marker genes involved in hepatic gluconeogenesis, but has a minimal effect on matrix metalloproteinase 9 (MMP-9), a GR responsive pro-inflammatory gene. Interestingly, the compound recruits neither coactivators nor corepressors to the GR complex but competes with glucocorticoids for the interaction between GR and a coactivator peptide. Moreover, NC3327 does not trigger GR nuclear translocation, but significantly blocks Dex-induced GR transportation to the nucleus, and thus appears to be a 'competitive' GR antagonist. Therefore, the non-steroidal compound, NC3327, may represent a new class of GR antagonists as potential therapeutics for a variety of cortisol-related endocrine disorders.

  3. Synthetic peptide antagonists of glucagon

    International Nuclear Information System (INIS)

    Unson, C.G.; Andreu, D.; Gurzenda, E.M.; Merrifield, R.B.

    1987-01-01

    Several glucagon analogs were synthesized in an effort to find derivatives that would bind with high affinity to the glucagon receptor of rat liver membranes but would not activate membrane-bound adenylate cyclase and, therefore, would serve as antagonists of the hormone. Measurements on a series of glucagon/secretin hybrids indicated that replacement of Asp 9 in glucagon by Glu 9 , found in secretin, was the important sequence difference in the N terminus of the two hormones. Further deletion of His 1 and introduction of a C-terminal amide resulted in des-His 1 -[Glu 9 ]glucagon amide, which had a 40% binding affinity relative to that of native glucagon but caused no detectable adenylate cyclase activation in the rat liver membrane. This antagonist completely inhibited the effect of a concentration of glucagon that alone gave a full agonist response. It had an inhibition index of 12. The pA 2 was 7.2. An attempt was made to relate conformation with receptor binding. The peptides were synthesized by solid-phase methods and purified to homogeneity by reverse-phase high-performance liquid chromatography on C 18 -silica columns

  4. PR130 is a modulator of the Wnt-signaling cascade that counters repression of the antagonist Naked cuticle

    NARCIS (Netherlands)

    Creyghton, M.P.; Roël, G.; Eichhorn, P.J.A.; Vredeveld, L.C.; Destrée, O.; Bernards, R.A.

    2006-01-01

    The Wnt-signaling cascade is required for several crucial steps during early embryogenesis, and its activity is modulated by various agonists and antagonists to provide spatiotemporal-specific signaling. Naked cuticle is a Wnt antagonist that itself is induced by Wnt signaling to keep Wnt signaling

  5. West syndrome associated with administration of a histamine H1 antagonist, oxatomide.

    Science.gov (United States)

    Yamashita, Yushiro; Isagai, Takeo; Seki, Yoshitaka; Ohya, Takashi; Nagamitsu, Shinichiro; Matsuishi, Toyojiro

    2004-01-01

    We report a 4-month-old female infant who developed West syndrome eleven days after administration of a histamine H1 antagonist, oxatomide, for atopic dermatitis. It has been reported that some histamine H1 antagonists induce seizures in epileptic patients. The age, the interval between oxatomide administration, and the onset of West syndrome and its clinical course were similar to two previously reported 3-month-old infants with West syndrome associated with ketotifen administration. We should be cautious in using the histamine H1 antagonists, oxatomide and ketotifen, in young infants because such agents could potentially disturb the anticonvulsive central histaminergic system.

  6. Oxytocin antagonist disrupts hypotension-evoked renin secretion and other responses in conscious rats

    DEFF Research Database (Denmark)

    Huang, W.; Sjöquist, M.; Skøtt, O.

    2001-01-01

    Previous experiments have indicated that arterial hypotension increases plasma oxytocin (OT) levels in rats and that OT infused intravenously causes an increase in plasma renin activity (PRA). The goal of the present study was to determine whether systemic administration of an OT receptor...... antagonist would attenuate the increase in PRA that is normally evoked by arterial hypotension in rats. In conscious male rats, intravenous injection of hydralazine or diazoxide produced sustained hypotension and evoked a significant increase in PRA, as expected. Intravenous infusion of an OT receptor...... antagonist did not alter the hypotension induced by hydralazine or diazoxide, but it did markedly blunt the induced increase in PRA. The OT receptor antagonist also blunted the hypotension-evoked increase in heart rate and plasma vasopressin levels, suggesting that the antagonist may have generally disrupted...

  7. Antiviral activity of formyl peptide receptor 2 antagonists against influenza viruses.

    Science.gov (United States)

    Courtin, Noémie; Fotso, Aurélien Fotso; Fautrad, Pierre; Mas, Floriane; Alessi, Marie-Christine; Riteau, Béatrice

    2017-07-01

    Influenza viruses are one of the most important respiratory pathogens worldwide, causing both epidemic and pandemic infections. The aim of the study was to evaluate the effect of FPR2 antagonists PBP10 and BOC2 on influenza virus replication. We determined that these molecules exhibit antiviral effects against influenza A (H1N1, H3N2, H6N2) and B viruses. FPR2 antagonists used in combination with oseltamivir showed additive antiviral effects. Mechanistically, the antiviral effect of PBP10 and BOC2 is mediated through early inhibition of virus-induced ERK activation. Finally, our preclinical studies showed that FPR2 antagonists protected mice from lethal infections induced by influenza, both in a prophylactic and therapeutic manner. Thus, FPR2 antagonists might be explored for novel treatments against influenza. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. The effect of H 1 and H 2 receptor antagonists on melanogenesis

    Directory of Open Access Journals (Sweden)

    Tag S Anbar

    2012-01-01

    Full Text Available Background: Histamine was found to stimulate melanogenesis in cultured human melanocytes specifically mediated by histamine H 2 receptors via protein kinase A activation. Based on this finding, the effect of topically applied H 2 antagonist on UVB-irradiated Guinea pigs′ skin was examined and found to be suppressive on the post-irradiation melanogenesis. Aims: In this study, we tried to explore the role of topically applied H 1 and H 2 receptor antagonists, in inhibition of UVB-induced melanization. Methods: The effect of topically applied H 1 and H 2 receptor antagonists in inhibition of melanization was done clinically and histochemically using Fontana Masson and DOPA reactions compared with placebo. Results: The post-irradiation pigmentation was found to be brownish/black instead of the original light brown color. This color change occurred below the shaved orange-red fur suggesting a switch of melanogenesis from pheomelanin to eumelanin. The induced pigmentation was suppressed by topically applied H 2 antagonist while both H 1 antagonist and vehicle had no effect. The microscopic examination showed that the keratinocytes in the H 2 antagonist-treated areas contained few melanosomes while the nearby dendrites are full of them. Conclusion: H 2 antagonists′ inhibition of UVB-induced pigmentation is not only due to suppression of melanization but also due to a specific action on melanosomes′ transfer.

  9. Autoras africanas: A favor de las mujeres=African authors: In favor of women

    Directory of Open Access Journals (Sweden)

    Socorro Suárez Lafuente

    2017-06-01

    Full Text Available Resumen: La cultura occidental produce binomios de poder fuertemente inscritos en el lenguaje y el imaginario colectivo. Las subversiones aparecen primero en la zona dominante, como el feminismo, que se extiende, posteriormente, a otros feminismos, igualmente lógicos y reivindicativos, pero con menos capacidad de visibilización en un mundo globalizado. Las mujeres de grupos minorizados que han conseguido acceder a la educación han levantado sus voces y utilizado su potencial creativo a favor de las silenciadas de su cultura, a las que no alcanzaban el feminismo blanco occidental. Amma Darko, Bessie Head y Chimamanda Ngozi Adichie son algunos de los nombres que encabezan un movimiento africano feminista, que prioriza la libertad individual de las mujeres y les hace sentirse orgullosas de ser africanas.   Abstract Western culture produces binaries of power that are deeply inscribed both in language and in the collective imaginarium. Subversions tend to appear in the more affluent class, as is the case with feminism, which later extend to other feminisms, equally important and vindicatory, but with fewer opportunities to become visible within a globalized world. Many women from minoritized groups have had access to education, have been able to use their creative force and have become the voice of many silent women who were not included in the successive waves of Western feminisms. Amma Darko, Bessie Head and Chimamanda Ngozi Adichie are but a few names at the forefront of African feminism, a movement that fights for the individual rights of women and makes them feel proud of their Africanism.

  10. New antagonist agents of neuropeptide y receptors

    Directory of Open Access Journals (Sweden)

    Ignacio Aldana

    2000-12-01

    Full Text Available In the CNS, NPY has been implicated in obesity and feeding, endocrine function and metabolism. Potent and selective rNPY antagonists will be able to probe the merits of this approach for the treatment of obesity. We report the synthesis and preliminary evaluation of some hydrazide derivatives as antagonists of rNPY.

  11. Interleukin-1-receptor antagonist in type 2 diabetes mellitus

    DEFF Research Database (Denmark)

    Larsen, Claus M; Faulenbach, Mirjam; Vaag, Allan

    2007-01-01

    BACKGROUND: The expression of interleukin-1-receptor antagonist is reduced in pancreatic islets of patients with type 2 diabetes mellitus, and high glucose concentrations induce the production of interleukin-1beta in human pancreatic beta cells, leading to impaired insulin secretion, decreased cell...... proliferation, and apoptosis. METHODS: In this double-blind, parallel-group trial involving 70 patients with type 2 diabetes, we randomly assigned 34 patients to receive 100 mg of anakinra (a recombinant human interleukin-1-receptor antagonist) subcutaneously once daily for 13 weeks and 36 patients to receive......, and the body-mass index were similar in the two study groups. Symptomatic hypoglycemia was not observed, and there were no apparent drug-related serious adverse events. CONCLUSIONS: The blockade of interleukin-1 with anakinra improved glycemia and beta-cell secretory function and reduced markers of systemic...

  12. Non-imidazole histamine NO-donor H3-antagonists.

    Science.gov (United States)

    Tosco, Paolo; Bertinaria, Massimo; Di Stilo, Antonella; Cena, Clara; Fruttero, Roberta; Gasco, Alberto

    2005-01-01

    Recently a series of H3-antagonists related to Imoproxifan was realised (I); in these products the oxime substructure of the lead was constrained in NO-donor furoxan systems and in the corresponding furazan derivatives. In this paper, a new series of compounds derived from I by substituting the imidazole ring with the ethoxycarbonylpiperazino moiety present in the non-imidazole H3-ligand A-923 is described. For all the products synthesis and preliminary pharmacological characterisation, as well as their hydrophilic-lipophilic balance, are reported. The imidazole ring replacement generally results in a decreased H3-antagonist activity with respect to the analogues of series I and, in some cases, induces relaxing effects on the electrically contracted guinea-pig ileum, probably due to increased affinity for other receptor systems.

  13. S179D prolactin: antagonistic agony!

    Science.gov (United States)

    Walker, Ameae M

    2007-09-30

    The aims of this review are three-fold: first, to collate what is known about the production and activities of phosphorylated prolactin (PRL), the latter largely, but not exclusively, as illustrated through the use of the molecular mimic, S179D PRL; second, to apply this and related knowledge to produce an updated model of prolactin-receptor interactions that may apply to other members of this cytokine super-family; and third, to promote a shift in the current paradigm for the development of clinically important growth antagonists. This third aim explains the title since, based on results with S179D PRL, it is proposed that agents which signal to antagonistic ends may be better therapeutics than pure antagonists-hence antagonistic agony. Since S179D PRL is not a pure antagonist, we have proposed the term selective prolactin receptor modulator (SPeRM) for this and like molecules.

  14. [Extracorporeal life support in calcium antagonist intoxication].

    Science.gov (United States)

    Groot, M W; Grewal, S; Meeder, H J; van Thiel, R J; den Uil, C A

    2017-01-01

    Intoxication with calcium antagonists is associated with poor outcome. Even mild calcium antagonist overdose may be fatal. A 51-year-old woman and a 51-year-old man came to the Accident and Emergency Department in severe shock after they had taken a calcium antagonist overdose. After extensive medicinal therapy had failed, they both needed extracorporeal life support (ECLS) as a bridge to recovery. In severe calcium antagonist overdose, the combination of vasoplegia and cardiac failure leads to refractory shock. ECLS temporarily supports the circulation and maintains organ perfusion. In this way ECLS functions as a bridge to recovery and may possibly save lives. Timely consultation with and referral to an ECLS centre is recommended in patients with calcium antagonist overdose.

  15. Histamine H4 receptor antagonists are superior to traditional antihistamines in the attenuation of experimental pruritus.

    Science.gov (United States)

    Dunford, Paul J; Williams, Kacy N; Desai, Pragnya J; Karlsson, Lars; McQueen, Daniel; Thurmond, Robin L

    2007-01-01

    Histamine is a potent mediator of itch in humans, yet histamine H(1) receptor antagonists have been shown to be of limited use in the treatment of certain chronic pruritic diseases. The histamine H(4) receptor is a recently described histamine receptor, expressed on hematopoietic cells, linked to the pathology of allergy and asthma. The contribution of the novel histamine H(4) receptor to histaminergic and allergic pruritus was investigated. Histamine and a selective histamine H(4) receptor agonist caused scratching responses in mice, which were almost completely attenuated in histamine H(4) receptor knockout mice or by pretreatment with the selective histamine H(4) receptor antagonist, JNJ 7777120. Pruritus induced by allergic mechanisms was also potently inhibited with histamine H(4) receptor antagonist treatment or in histamine H(4) receptor knockout mice. In all cases, the inhibitory effect of histamine H(4) receptor antagonist was greater than those observed with histamine H(1) receptor antagonists. The histamine H(4) receptor-mediated pruritus was shown to be independent of mast cells or other hematopoietic cells and may result from actions on peripheral neurons. These results demonstrate that the histamine H(4) receptor is involved in pruritic responses in mice to a greater extent than the histamine H(1) receptor. Histamine H(4) receptor antagonists may have therapeutic utility for treating chronic pruritic diseases in humans where histamine H(1) receptor antagonists are not effective.

  16. Differential antiepileptic effects of the organic calcium antagonists verapamil and flunarizine in neurons of organotypic neocortical explants from newborn rats

    NARCIS (Netherlands)

    Bingmann, D; Speckmann, E J; Baker, R E; Ruijter, J; de Jong, B. M.

    1988-01-01

    Effects of the organic calcium antagonists verapamil and flunarizine on pentylenetetrazol induced paroxysmal depolarizations were tested in organotypic neocortical explants taken from neonatal rats. In these in vitro experiments the papaverin derivative verapamil depressed, and finally abolished,

  17. Opioid antagonists for alcohol dependence.

    Science.gov (United States)

    Rösner, Susanne; Hackl-Herrwerth, Andrea; Leucht, Stefan; Vecchi, Simona; Srisurapanont, Manit; Soyka, Michael

    2010-12-08

    Alcohol dependence belongs to the globally leading health risk factors. Therapeutic success of psychosocial programs for relapse prevention is moderate and could be increased by an adjuvant treatment with the opioid antagonists naltrexone and nalmefene. To determine the effectiveness and tolerability of opioid antagonists in the treatment of alcohol dependence. We searched the Cochrane Drugs and Alcohol Group (CDAG) Specialized Register, PubMed, EMBASE and CINAHL in January 2010 and inquired manufacturers and researchers for unpublished trials. All double-blind randomised controlled trials (RCTs) which compare the effects of naltrexone or nalmefene with placebo or active control on drinking-related outcomes. Two authors independently extracted outcome data. Trial quality was assessed by one author and cross-checked by a second author. Based on a total of 50 RCTs with 7793 patients, naltrexone reduced the risk of heavy drinking to 83% of the risk in the placebo group RR 0.83 (95% CI 0.76 to 0.90) and decreased drinking days by about 4%, MD -3.89 (95% CI -5.75 to -2.04). Significant effects were also demonstrated for the secondary outcomes of the review including heavy drinking days, MD - 3.25 (95% CI -5.51 to -0.99), consumed amount of alcohol, MD - 10.83 (95% CI -19.69 to -1.97) and gamma-glutamyltransferase, MD - 10.37 (95% CI -18.99 to -1.75), while effects on return to any drinking, RR 0.96 (95 CI 0.92 to 1.00) missed statistical significance. Side effects of naltrexone were mainly gastrointestinal problems (e.g. nausea: RD 0.10; 95% CI 0.07 to 0.13) and sedative effects (e.g. daytime sleepiness: RD 0.09; 95% CI 0.05 to 0.14). Based on a limited study sample, effects of injectable naltrexone and nalmefene missed statistical significance. Effects of industry-sponsored studies, RR 0.90 (95% CI 0.78 to 1.05) did not significantly differ from those of non-profit funded trials, RR 0.84 (95% CI 0.77 to 0.91) and the linear regression test did not indicate publication

  18. Opioid antagonists with minimal sedation for opioid withdrawal.

    Science.gov (United States)

    Gowing, Linda; Ali, Robert; White, Jason M

    2017-05-29

    without indicating the level of care provided.The included studies were heterogeneous in terms of the type of opioid antagonist treatment regimen, the comparator, the outcome measures assessed, and the means of assessing outcomes. As a result, the validity of any estimates of overall effect is doubtful, therefore we did not calculate pooled results for any of the analyses.The quality of the evidence for treatment with an opioid antagonist-adrenergic agonist combination versus an alpha 2 -adrenergic agonist is very low. Two studies reported data on peak withdrawal severity, and four studies reported data on the average severity over the period of withdrawal. Peak withdrawal induced by opioid antagonists in combination with an adrenergic agonist appears to be more severe than withdrawal managed with clonidine or lofexidine alone, but the average severity over the withdrawal period is less. In some situations antagonist-induced withdrawal may be associated with significantly higher rates of treatment completion compared to withdrawal managed with adrenergic agonists. However, this result was not consistent across studies, and the extent of any benefit is highly uncertain.We could not extract any data on the occurrence of adverse events, but two studies reported delirium or confusion following the first dose of naltrexone. Delirium may be more likely with higher initial doses and with naltrexone rather than naloxone (which has a shorter half-life), but we could not confirm this from the available evidence.Insufficient data were available to make any conclusions on the best duration of treatment. Using opioid antagonists plus alpha 2 -adrenergic agonists is a feasible approach for managing opioid withdrawal. However, it is unclear whether this approach reduces the duration of withdrawal or facilitates transfer to naltrexone treatment to a greater extent than withdrawal managed primarily with an adrenergic agonist.A high level of monitoring and support is desirable for several

  19. Effect of BN 52021, a specific antagonist of platelet activating factor (PAF-acether), on calcium movements and phosphatidic acid production induced by PAF-acether in human platelets

    Energy Technology Data Exchange (ETDEWEB)

    Simon, M.F.; Chap, H.; Braquet, P.; Douste-Blazy, L.

    1987-02-15

    /sup 32/P-labelled human platelets loaded with quin 2 and pretreated with aspirin were stimulated with 1-100 nM platelet activating factor (PAF-acether or 1-0-alkyl-2-acetyl-sn-glycero-3-phosphocholine) in a medium containing the ADP-scavenging system creatine phosphate/creatine phosphokinase. Under these conditions, PAF-acether evoked a characteristic fluorescence change allowing to quantify elevations in cytoplasmic free Ca/sup 2 +/ from internal stores (Ca/sup 2 +/ mobilization) or from external medium (Ca/sup 2 +/ influx), as well as an increased production of phosphatidic acid, reflecting phospholipase C activation. These effects, which can be attributed to PAF-acether only and not to released products such as ADP or thromboxane A2, were strongly inhibited in a dose-dependent manner by BN 52021, a specific antagonist of PAF-acether isolated from Ginkgo biloba. As the drug remained inactive against the same effects elicited by thrombin, it is concluded that BN 52021 does not interfere directly with the mechanism of transmembrane signalling involving inositol-phospholipids or (and) some putative receptor-operated channels, but rather acts on the binding of PAF-acether to its presumed membrane receptor.

  20. Sarpogrelate hydrochloride, a selective 5-hydroxytryptamine(2A) antagonist, augments autologous bone marrow mononuclear cell implantation-induced improvement in endothelium-dependent vasodilation in patients with critical limb ischemia.

    Science.gov (United States)

    Higashi, Yukihito; Miyazaki, Masanori; Goto, Chikara; Sanada, Hiroaki; Sueda, Taijiro; Chayama, Kazuaki

    2010-01-01

    The purpose of this study was to determine the effect of a combination of bone marrow mononuclear cell (BM-MNC) implantation and sarpogrelate, a selective 5-HT(2A) antagonist, on endothelial function in patients with critical limb ischemia (CLI). We evaluated the leg blood flow (LBF) responses to acetylcholine (ACh) and sodium nitroprusside before and after BM-MNC implantation in 16 patients with CLI. We divided patients with CLI into 2 groups: those cotreated with sarpogrelate orally for 12 weeks (sarpogrelate group, n = 8) and those who remained on conventional therapy (control group, n = 8). LBF was measured by strain gauge plethysmography. BM-MNC implantation improved ankle brachial pressure index, transcutaneous oxygen pressure, and pain-free walking time. There was no significant difference in these parameters between the 2 groups. Before BM-MNC implantation, LBF responses to ACh were similar in the sarpogrelate group and control group. Twelve weeks of BM-MNC implantation enhanced LBF responses to ACh in the sarpogrelate and control groups. After 12 weeks of BM-MNC implantation, LBF response to ACh was significantly greater in the sarpogrelate group than in the control group. BM-MNC implantation did not alter the LBF responses to sodium nitroprusside in either group. These findings suggest that BM-MNC implantation improved not only limb ischemic symptoms but also endothelium-dependent vasodilation in patients with CLI. A combination of BM-MNC implantation and sarpogrelate had a more beneficial effect on vascular function in these patients.

  1. Twisted gastrulation, a BMP antagonist, exacerbates podocyte injury.

    Directory of Open Access Journals (Sweden)

    Sachiko Yamada

    Full Text Available Podocyte injury is the first step in the progression of glomerulosclerosis. Previous studies have demonstrated the beneficial effect of bone morphogenetic protein 7 (Bmp7 in podocyte injury and the existence of native Bmp signaling in podocytes. Local activity of Bmp7 is controlled by cell-type specific Bmp antagonists, which inhibit the binding of Bmp7 to its receptors. Here we show that the product of Twisted gastrulation (Twsg1, a Bmp antagonist, is the central negative regulator of Bmp function in podocytes and that Twsg1 null mice are resistant to podocyte injury. Twsg1 was the most abundant Bmp antagonist in murine cultured podocytes. The administration of Bmp induced podocyte differentiation through Smad signaling, whereas the simultaneous administration of Twsg1 antagonized the effect. The administration of Bmp also inhibited podocyte proliferation, whereas simultaneous administration of Twsg1 antagonized the effect. Twsg1 was expressed in the glomerular parietal cells (PECs and distal nephron of the healthy kidney, and additionally in damaged glomerular cells in a murine model of podocyte injury. Twsg1 null mice exhibited milder hypoalbuminemia and hyperlipidemia, and milder histological changes while maintaining the expression of podocyte markers during podocyte injury model. Taken together, our results show that Twsg1 plays a critical role in the modulation of protective action of Bmp7 on podocytes, and that inhibition of Twsg1 is a promising means of development of novel treatment for podocyte injury.

  2. Favorability for uranium in tertiary sedimentary rocks, southwestern Montana

    International Nuclear Information System (INIS)

    Wopat, M.A.; Curry, W.E.; Robins, J.W.; Marjaniemi, D.K.

    1977-10-01

    Tertiary sedimentary rocks in the basins of southwestern Montana were studied to determine their favorability for potential uranium resources. Uranium in the Tertiary sedimentary rocks was probably derived from the Boulder batholith and from silicic volcanic material. The batholith contains numerous uranium occurrences and is the most favorable plutonic source for uranium in the study area. Subjective favorability categories of good, moderate, and poor, based on the number and type of favorable criteria present, were used to classify the rock sequences studied. Rocks judged to have good favorability for uranium deposits are (1) Eocene and Oligocene strata and undifferentiated Tertiary rocks in the western Three Forks basin and (2) Oligocene rocks in the Helena basin. Rocks having moderate favorability consist of (1) Eocene and Oligocene strata in the Jefferson River, Beaverhead River, and lower Ruby River basins, (2) Oligocene rocks in the Townsend and Clarkston basins, (3) Miocene and Pliocene rocks in the Upper Ruby River basin, and (4) all Tertiary sedimentary formations in the eastern Three Forks basin, and in the Grasshopper Creek, Horse Prairie, Medicine Lodge Creek, Big Sheep Creek, Deer Lodge, Big Hole River, and Bull Creek basins. The following have poor favorability: (1) the Beaverhead Conglomerate in the Red Rock and Centennial basins, (2) Eocene and Oligocene rocks in the Upper Ruby River basin, (3) Miocene and Pliocene rocks in the Townsend, Clarkston, Smith River, and Divide Creek basins, (4) Miocene through Pleistocene rocks in the Jefferson River, Beaverhead River, and Lower Ruby River basins, and (5) all Tertiary sedimentary rocks in the Boulder River, Sage Creek, Muddy Creek, Madison River, Flint Creek, Gold Creek, and Bitterroot basins

  3. Effects of estrogen antagonists on estradiol-enhanced radiation transformation in vitro

    International Nuclear Information System (INIS)

    Umans, R.S.; Kenneddy, A.R.

    1988-01-01

    We have previously reported that radiation and 17β-estrediol can induce transformation in vitro in C3H 10T1/2 cells. In the present series of experiments, we have observed that antagonists of estrogen action, such as c-AMP activating agents(Theophylinne and dibutylc-AMP) and the antiestrogens tamoxifen, suppress radiation/17β-estradiol enhanced transformation in vitro. None of these known estrogen antagonists had a significant effect on transformation induced by radiation alone. Our results with added dibutyl c-AMP, theophylline and tamoxifen suggest that estrogen receptor complex formation may play a role in estrogen-enhanced radiation transformation in vitro (author)

  4. GABAA receptor partial agonists and antagonists

    DEFF Research Database (Denmark)

    Krall, Jacob; Balle, Thomas; Krogsgaard-Larsen, Niels

    2015-01-01

    to the local temporal pattern of GABA impact, enabling phasic or tonic inhibition. Specific GABAAR antagonists are essential tools for physiological and pharmacological elucidation of the different type of GABAAR inhibition. However, distinct selectivity among the receptor subtypes (populations) has been shown...... antagonists and describes the development of potent antagonists from partial agonists originally derived from the potent GABAAR agonist muscimol. In this process, several heterocyclic aromatic systems have been used in combination with structural models in order to map the orthosteric binding site...... and to reveal structural details to be used for obtaining potency and subtype selectivity. The challenges connected to functional characterization of orthosteric GABAAR partial agonists and antagonists, especially with regard to GABAAR stoichiometry and alternative binding sites are discussed. GABAAR...

  5. Calcium antagonists for aneurysmal subarachnoid haemorrhage

    NARCIS (Netherlands)

    Dorhout Mees, S. M.; Rinkel, G. J. E.; Feigin, V. L.; Algra, A.; van den Bergh, W. M.; Vermeulen, M.; van Gijn, J.

    2007-01-01

    BACKGROUND: Secondary ischaemia is a frequent cause of poor outcome in patients with subarachnoid haemorrhage (SAH). Its pathogenesis has been incompletely elucidated, but vasospasm probably is a contributing factor. Experimental studies have suggested that calcium antagonists can prevent or reverse

  6. Antagonist wear by polished zirconia crowns.

    Science.gov (United States)

    Hartkamp, Oliver; Lohbauer, Ulrich; Reich, Sven

    The aim of this in vivo study was to measure antagonist wear caused by polished monolithic posterior zirconia crowns over a 24-month period using the intraoral digital impression (IDI) technique. Thirteen zirconia crowns were placed in nine patients. The crowns and adjacent teeth were captured using an intraoral scanner (Lava C.O.S.). The corresponding antagonist teeth and the respective neighboring teeth were also scanned. Scanning was performed immediately after the restoration (baseline) as well as 12 and 24 months after crown placement. Geomagic Qualify software was used to superimpose the follow-up data sets onto the corresponding baseline data set, identify wear sites, and measure maximum vertical height loss in each individual wear site. Overall antagonist wear was then determined as the mean of wear rates measured in all of the individual antagonist units. In addition, wear rates in enamel and ceramic antagonists were analyzed as part of the scope of this study. The maximum mean wear with standard deviation (SD) in the overall sample with a total of nine patients, 13 antagonist units, and 98 evaluable wear sites was 86 ± 23 µm at 12 months, and 103 ± 39 µm at 24 months. The maximum mean wear in the enamel antagonist subgroup was 87 ± 41 µm at 12 months, and 115 ± 71 µm at 24 months; and in the ceramic antagonist subgroup 107 ± 22 µm at 12 months, and 120 ± 27 µm at 24 months. The wear rates determined in this study are comparable to those of existing studies. The IDI technique of wear analysis can be carried out in a practical manner and produces useful results.

  7. CXCR4 Antagonists: A Screening Strategy for Identification of Functionally Selective Ligands.

    Science.gov (United States)

    Castaldo, C; Benicchi, T; Otrocka, M; Mori, E; Pilli, E; Ferruzzi, P; Valensin, S; Diamanti, D; Fecke, W; Varrone, M; Porcari, V

    2014-07-01

    The CXC chemokine receptor 4 (CXCR4) is a widely expressed G protein-coupled receptor implicated in several diseases. In cancer, an increased number of surface CXCR4 receptors, in parallel with aberrant signaling, have been reported to influence several aspects of malignancy progression. CXCR4 activation by the specific ligand C-X-C motif chemokine 12 (CXCL12) induces several intracellular signaling pathways that have been selectively related to malignancy depending on the tissue or cell type. We developed a panel of CXCR4 screening assays investigating Gα(i)-mediated cyclic adenosine monophosphate modulation, β-arrestin recruitment, and receptor internalization. All of the assays were set up in recombinant cells and were used to test four reported CXCR4 antagonists. Consequently, a set of hit compounds, deriving from a screening campaign of a 30,000-small-molecule internal library, was profiled with the different assays. We identified several compounds showing a pathway-selective activity: antagonists on a Gα(i)-dependent pathway; antagonists on both the β-arrestin and Gα(i)-dependent pathways, some of which induce receptor internalization; and compounds with an antagonist behavior in all of the readouts. The identified biased antagonists induce different functional states on CXCR4 and preferentially affect specific downstream responses from the activated receptor, thus providing an improved therapeutic profile for correction of CXCR4 abnormal signaling. © 2014 Society for Laboratory Automation and Screening.

  8. Development of the Adverse Outcome Pathway (AOP): Chronic binding of antagonist to N-methyl-d-aspartate receptors (NMDARs) during brain development induces impairment of learning and memory abilities of children.

    Science.gov (United States)

    Sachana, Magdalini; Rolaki, Alexandra; Bal-Price, Anna

    2018-03-07

    The Adverse Outcome Pathways (AOPs) are designed to provide mechanistic understanding of complex biological systems and pathways of toxicity that result in adverse outcomes (AOs) relevant to regulatory endpoints. AOP concept captures in a structured way the causal relationships resulting from initial chemical interaction with biological target(s) (molecular initiating event) to an AO manifested in individual organisms and/or populations through a sequential series of key events (KEs), which are cellular, anatomical and/or functional changes in biological processes. An AOP provides the mechanistic detail required to support chemical safety assessment, the development of alternative methods and the implementation of an integrated testing strategy. An example of the AOP relevant to developmental neurotoxicity (DNT) is described here following the requirements of information defined by the OECD Users' Handbook Supplement to the Guidance Document for developing and assessing AOPs. In this AOP, the binding of an antagonist to glutamate receptor N-methyl-d-aspartate (NMDAR) receptor is defined as MIE. This MIE triggers a cascade of cellular KEs including reduction of intracellular calcium levels, reduction of brain derived neurotrophic factor release, neuronal cell death, decreased glutamate presynaptic release and aberrant dendritic morphology. At organ level, the above mentioned KEs lead to decreased synaptogenesis and decreased neuronal network formation and function causing learning and memory deficit at organism level, which is defined as the AO. There are in vitro, in vivo and epidemiological data that support the described KEs and their causative relationships rendering this AOP relevant to DNT evaluation in the context of regulatory purposes. Copyright © 2018. Published by Elsevier Inc.

  9. LY395756, an mGluR2 agonist and mGluR3 antagonist, enhances NMDA receptor expression and function in the normal adult rat prefrontal cortex, but fails to improve working memory and reverse MK801-induced working memory impairment.

    Science.gov (United States)

    Li, Meng-Lin; Yang, Sha-Sha; Xing, Bo; Ferguson, Brielle R; Gulchina, Yelena; Li, Yan-Chun; Li, Feng; Hu, Xi-Quan; Gao, Wen-Jun

    2015-11-01

    Targeting group II metabotropic glutamate receptors (mGluR2/3) has been proposed to correct the dysfunctional glutamatergic system, particularly NMDA receptor (NMDAR) hypofunction, for treatment of schizophrenia. However, how activation of mGluR2/3 affects NMDAR function in adult animals remains elusive. Here we show the effects of LY395756 (LY39), a compound acting as both an mGluR2 agonist and mGluR3 antagonist, on the NMDAR expression and function of normal adult rat prefrontal cortex (PFC) as well as working memory function in the MK801 model of schizophrenia. We found that in vivo administration of LY39 significantly increased the total protein levels of NMDAR subunits and NR2B phosphorylationin the PFC, along with the amplitude of NMDAR-mediated miniature excitatory postsynaptic currents (mEPSC) in the prefrontal cortical neurons. Moreover, LY39 also significantly increased mTOR and pmTOR expression, but not ERK1/2, Akt, and GSK3β, suggesting an activation of mTOR signaling. Indeed, the mTOR inhibitor rapamycin, and actinomycin-D, a transcription inhibitor, blocked the enhanced effects of LY39 on NMDAR-mEPSCs. These results indicate that LY39 regulates NMDAR expression and function through unidentified mTOR-mediated protein synthesis in the normal adult rat PFC. However, this change is insufficient to affect working memory function in normal animals, nor to reverse the MK801-induced working memory deficit. Our data provide the first evidence of an in vivo effect of a novel compound that acts as both an mGluR2 agonist and mGluR3 antagonist on synaptic NMDAR expression and function in the adult rat PFC, although its effect -on PFC-dependent cognitive function remains to be explored. Copyright © 2015 Elsevier Inc. All rights reserved.

  10. Cordilleran metamorphic core complexes and their uranium favorability

    International Nuclear Information System (INIS)

    Coney, P.J.; Reynolds, S.J.

    1980-11-01

    The objective of this report is to provide a descriptive body of knowledge on Cordilleran metamorphic core complexes including their lithologic and structural characteristics, their distribution within the Cordillera, and their evolutionary history and tectonic setting. The occurrence of uranium in the context of possibility for uranium concentration is also examined. This volume contains appendices of the following: annotated bibliography of Cordilleran metamorphic core complexes; annotated bibliography of the uranium favorability of Cordilleran metamorphic core complexes; uranium occurrences in the Cordilleran metamorphic core complex belt; and geology, uranium favorability, uranium occurrences and tectonic maps of individual Cordilleran metamorphic core complexes; and locations, lithologic descriptions, petrographic information and analytical data for geochemical samples

  11. Antistress Effects of Rosa rugosa Thunb. on Total Sleep Deprivation-Induced Anxiety-Like Behavior and Cognitive Dysfunction in Rat: Possible Mechanism of Action of 5-HT6 Receptor Antagonist.

    Science.gov (United States)

    Na, Ju-Ryun; Oh, Dool-Ri; Han, SeulHee; Kim, Yu-Jin; Choi, EunJin; Bae, Donghyuck; Oh, Dong Hwan; Lee, Yoo-Hyun; Kim, Sunoh; Jun, Woojin

    2016-09-01

    Our previous results suggest that the Rosa rugosa Thunb. (family Rosaceae) alleviates endurance exercise-induced stress by decreasing oxidative stress levels. This study aimed to screen and identify the physiological antistress effects of an extract of R. rugosa (RO) on sleep deprivation-induced anxiety-like behavior and cognitive tests (in vivo) and tested for hippocampal CORT and monoamine levels (ex vivo), corticosterone (CORT)-induced injury, N-methyl-d-aspartate (NMDA) receptor, and serotonin 6 (5-hydroxytryptamine 6, 5-HT6) receptor activities (in vitro) in search of active principles and underlying mechanisms of action. We confirmed the antistress effects of RO in a sleep-deprived stress model in rat and explored the underlying mechanisms of its action. In conclusion, an R. rugosa extract showed efficacy and potential for use as an antistress therapy to treat sleep deprivation through its antagonism of the 5-HT6 receptor and resulting inhibition of cAMP activity.

  12. Full domain closure of the ligand-binding core of the ionotropic glutamate receptor iGluR5 induced by the high affinity agonist dysiherbaine and the functional antagonist 8,9-dideoxyneodysiherbaine

    DEFF Research Database (Denmark)

    Frydenvang, Karla Andrea; Lash, L Leanne; Naur, Peter

    2009-01-01

    The prevailing structural model for ligand activation of ionotropic glutamate receptors posits that agonist efficacy arises from the stability and magnitude of induced domain closure in the ligand-binding core structure. Here we describe an exception to the correlation between ligand efficacy and...

  13. 5-HT6 receptor antagonist attenuates the memory deficits associated with neuropathic pain and improves the efficacy of gabapentinoids.

    Science.gov (United States)

    Jayarajan, Pradeep; Nirogi, Ramakrishna; Shinde, Anil; Goura, Venkatesh; Babu, Vuyyuru Arun; Yathavakilla, Sumanth; Bhyrapuneni, Gopinadh

    2015-10-01

    Memory deficit is a co-morbid disorder in patients suffering from neuropathic pain. Gabapentin and pregabalin (gabapentinoids) are among the widely prescribed medications for the treatment of neuropathic pain. Memory loss and sedation are the commonly reported side effects with gabapentinoids. Improving the cognitive functions and attenuating drug-induced side effects may play a crucial role in the management of pain. We evaluated the effects of 5-HT6 receptor antagonists on the memory deficits associated with neuropathy. We also studied the effects of 5-HT6 receptor antagonists on the side effects, and the analgesic effects of gabapentinoids. 5-HT6 receptor antagonists attenuated the cognitive deficits in neuropathic rats. Neuropathic rats co-treated with 5-HT6 receptor antagonist and gabapentinoids showed improvement in memory. 5-HT6 receptor antagonists enhanced the analgesic effects of gabapentinoids but had no effect on the motor side effects. The observed effects may not be due to pharmacokinetic interactions. 5-HT6 receptor antagonist attenuate the cognitive deficits associated with neuropathy, and this effect is also seen when co-treated with gabapentinoids. Since, 5-HT6 antagonists improved the effectiveness of gabapentinoids, reduction in the dosage and frequency of gabapentinoids treatment may reduce the side effects. Combining 5-HT6 receptor antagonist with gabapentinoids may offer a novel treatment strategy for neuropathic pain. Copyright © 2015 Institute of Pharmacology, Polish Academy of Sciences. Published by Elsevier Urban & Partner Sp. z o.o. All rights reserved.

  14. 11 CFR 7.8 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-01-01

    ... affected by the performance or nonperformance of the Commissioner or employee's official duty. (b... Employees or Commissioners § 7.8 Gifts, entertainment, and favors. (a) A Commissioner or employee of the... persons concerned which are the motivating factors; (2) To the acceptance of food, refreshments, and...

  15. 22 CFR 1203.735-305 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Gifts, entertainment, and favors. 1203.735-305 Section 1203.735-305 Foreign Relations UNITED STATES INTERNATIONAL DEVELOPMENT COOPERATION AGENCY EMPLOYEE RESPONSIBILITIES AND CONDUCT Ethical and Other Conduct and Responsibilities of Special Government Employees § 1203...

  16. 22 CFR 1203.735-202 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-04-01

    ... 22 Foreign Relations 2 2010-04-01 2010-04-01 true Gifts, entertainment, and favors. 1203.735-202 Section 1203.735-202 Foreign Relations UNITED STATES INTERNATIONAL DEVELOPMENT COOPERATION AGENCY EMPLOYEE..., contractual or other business or financial relations with the employee's agency; (2) Conducts operations or...

  17. Preschoolers Reduce Inequality While Favoring Individuals with More

    Science.gov (United States)

    Li, Vivian; Spitzer, Brian; Olson, Kristina R.

    2014-01-01

    Inequalities are everywhere, yet little is known about how children respond to people affected by inequalities. This article explores two responses--minimizing inequalities and favoring those who are advantaged by them. In Studies 1a (N = 37) and 1b (N = 38), 4- and 5-year-olds allocated a resource to a disadvantaged recipient, but judged…

  18. 18 CFR 706.202 - Gifts, entertainment, and favors.

    Science.gov (United States)

    2010-04-01

    ... 18 Conservation of Power and Water Resources 2 2010-04-01 2010-04-01 false Gifts, entertainment, and favors. 706.202 Section 706.202 Conservation of Power and Water Resources WATER RESOURCES COUNCIL... loans from banks or other financial institutions on customary terms to finance proper and usual...

  19. Palliation of bone cancer pain by antagonists of platelet-activating factor receptors.

    Directory of Open Access Journals (Sweden)

    Katsuya Morita

    Full Text Available Bone cancer pain is the most severe among cancer pain and is often resistant to current analgesics. Thus, the development of novel analgesics effective at treating bone cancer pain are desired. Platelet-activating factor (PAF receptor antagonists were recently demonstrated to have effective pain relieving effects on neuropathic pain in several animal models. The present study examined the pain relieving effect of PAF receptor antagonists on bone cancer pain using the femur bone cancer (FBC model in mice. Animals were injected with osteolytic NCTC2472 cells into the tibia, and subsequently the effects of PAF receptor antagonists on pain behaviors were evaluated. Chemical structurally different type of antagonists, TCV-309, BN 50739 and WEB 2086 ameliorated the allodynia and improved pain behaviors such as guarding behavior and limb-use abnormalities in FBC model mice. The pain relieving effects of these antagonists were achieved with low doses and were long lasting. Blockade of spinal PAF receptors by intrathecal injection of TCV-309 and WEB 2086 or knockdown of the expression of spinal PAF receptor protein by intrathecal transfer of PAF receptor siRNA also produced a pain relieving effect. The amount of an inducible PAF synthesis enzyme, lysophosphatidylcholine acyltransferase 2 (LPCAT2 protein significantly increased in the spinal cord after transplantation of NCTC 2472 tumor cells into mouse tibia. The combination of morphine with PAF receptor antagonists develops marked enhancement of the analgesic effect against bone cancer pain without affecting morphine-induced constipation. Repeated administration of TCV-309 suppressed the appearance of pain behaviors and prolonged survival of FBC mice. The present results suggest that PAF receptor antagonists in combination with, or without, opioids may represent a new strategy for the treatment of persistent bone cancer pain and improve the quality of life of patients.

  20. Interlocus sexually antagonistic coevolution can create indirect selection for increased recombination.

    Science.gov (United States)

    Dapper, Amy L; Lively, Curtis M

    2014-04-01

    The ubiquity of recombination in nature is a paradox because it breaks up combinations of alleles favored by natural selection. Theoretical work has shown that antagonistic coevolution between hosts and parasites can result in rapid fluctuations in epistasis that can create a short-term advantage to recombination. Here, we show that another kind of antagonistic coevolution, interlocus sexually antagonistic coevolution (SAC), can also create indirect selection for modifiers that increase the rate of recombination, and that it can lead to very high levels of recombination at equilibrium. Recombination is favored because interlocus SAC creates heterogeneity in the strength and direction of selection, both within and between generations, which maintains an excess of disadvantageous haplotypes in the population. This result is similar to and consistent with dynamics of fluctuating epistasis produced in models of host-parasite coevolution. However, the conditions under which interlocus SAC provides an advantage to recombination are more permissive. © 2013 The Author(s). Evolution © 2013 The Society for the Study of Evolution.

  1. 5-HT2B Receptor Antagonists Inhibit Fibrosis and Protect from RV Heart Failure

    Directory of Open Access Journals (Sweden)

    Wiebke Janssen

    2015-01-01

    Full Text Available Objective. The serotonin (5-HT pathway was shown to play a role in pulmonary hypertension (PH, but its functions in right ventricular failure (RVF remain poorly understood. The aim of the current study was to investigate the effects of Terguride (5-HT2A and 2B receptor antagonist or SB204741 (5-HT2B receptor antagonist on right heart function and structure upon pulmonary artery banding (PAB in mice. Methods. Seven days after PAB, mice were treated for 14 days with Terguride (0.2 mg/kg bid or SB204741 (5 mg/kg day. Right heart function and remodeling were assessed by right heart catheterization, magnetic resonance imaging (MRI, and histomorphometric methods. Total secreted collagen content was determined in mouse cardiac fibroblasts isolated from RV tissues. Results. Chronic treatment with Terguride or SB204741 reduced right ventricular fibrosis and showed improved heart function in mice after PAB. Moreover, 5-HT2B receptor antagonists diminished TGF-beta1 induced collagen synthesis of RV cardiac fibroblasts in vitro. Conclusion. 5-HT2B receptor antagonists reduce collagen deposition, thereby inhibiting right ventricular fibrosis. Chronic treatment prevented the development and progression of pressure overload-induced RVF in mice. Thus, 5-HT2B receptor antagonists represent a valuable novel therapeutic approach for RVF.

  2. Bartonella quintana lipopolysaccharide is a natural antagonist of Toll-like receptor 4.

    NARCIS (Netherlands)

    Popa, C.; Abdollahi-Roodsaz, S.; Joosten, L.A.B.; Takahashi, N.; Sprong, T.; Matera, G.; Liberto, M.C.; Foca, A.; Deuren, M. van; Kullberg, B.J.; Berg, W.B. van den; Meer, J.W.M. van der; Netea, M.G.

    2007-01-01

    Bartonella quintana is a gram-negative microorganism that causes trench fever and chronic bacteremia. B. quintana lipopolysaccharide (LPS) was unable to induce the production of proinflammatory cytokines in human monocytes. Interestingly, B. quintana LPS is a potent antagonist of Toll-like receptor

  3. Regarding the unitary theory of agonist and antagonist action at presynaptic adrenoceptors.

    Science.gov (United States)

    Kalsner, S; Abdali, S A

    2001-06-01

    1. The linkage between potentiation of field stimulation-induced noradrenaline release and blockade of the presynaptic inhibitory effect of exogenous noradrenaline by a presynaptic antagonist was examined in superfused rabbit aorta preparations. 2. Rauwolscine clearly potentiated the release of noradrenaline in response to 100 pulses at 2 Hz but reduced the capacity of noradrenaline to inhibit transmitter release to a questionable extent, and then only when comparisons were made with untreated, rather then to rauwolscine-treated, controls. 3. Aortic preparations exposed for 60 min to rauwolscine followed by superfusion with antagonist-free Krebs for 60 min retained the potentiation of stimulation-induced transmitter release but no antagonism of the noradrenaline-induced inhibition could be detected at either of two noradrenaline concentrations when comparisons were made with rauwolscine treated controls. 4. Comparisons of the inhibitory effect of exogenous noradrenaline (1.8 x 10-6 M) on transmitter efflux in the presence and absence of rauwolscine pretreatment revealed that the antagonist enhanced rather than antagonized the presynaptic inhibition by noradrenaline. 5 It is concluded that the unitary hypothesis that asserts that antagonist enhancement of transmitter release and its blockade of noradrenaline induced inhibition are manifestations of a unitary event are not supportable.

  4. Effect of calmodulin antagonists on contraction and45Ca movements in rat aorta

    NARCIS (Netherlands)

    Wermelskirchen, D.; Koch, P.; Wilhelm, D.; Nebel, U.; Leidig, A.; Wilffert, B.; Peters, Thies

    1989-01-01

    To study the selectivity of calmodulin antagonists it was assumed that they should inhibit noradrenaline (NA)- and K+-induced contractions similarly without an accompanying inhibition of45Ca uptake. Therefore, in isolated rat aorta the effects of W-7, calmidazolium and trifluoperazine on contraction

  5. Cytoskeleton-centric protein transportation by exosomes transforms tumor-favorable macrophages

    Science.gov (United States)

    Cui, Yizhi; Zhou, Yanlong; Yin, Xingfeng; Guo, Jiahui; Zhang, Gong; Wang, Tong; He, Qing-Yu

    2016-01-01

    The exosome is a key initiator of pre-metastatic niche in numerous cancers, where macrophages serve as primary inducers of tumor microenvironment. However, the proteome that can be exosomally transported from cancer cells to macrophages has not been sufficiently characterized so far. Here, we used colorectal cancer (CRC) exosomes to educate tumor-favorable macrophages. With a SILAC-based mass spectrometry strategy, we successfully traced the proteome transported from CRC exosomes to macrophages. Such a proteome primarily focused on promoting cytoskeleton rearrangement, which was biologically validated with multiple cell lines. We reproduced the exosomal transportation of functional vimentin as a proof-of-concept example. In addition, we found that some CRC exosomes could be recognized by macrophages via Fc receptors. Therefore, we revealed the active and necessary role of exosomes secreted from CRC cells to transform cancer-favorable macrophages, with the cytoskeleton-centric proteins serving as the top functional unit. PMID:27602764

  6. Cytoskeleton-centric protein transportation by exosomes transforms tumor-favorable macrophages.

    Science.gov (United States)

    Chen, Zhipeng; Yang, Lijuan; Cui, Yizhi; Zhou, Yanlong; Yin, Xingfeng; Guo, Jiahui; Zhang, Gong; Wang, Tong; He, Qing-Yu

    2016-10-11

    The exosome is a key initiator of pre-metastatic niche in numerous cancers, where macrophages serve as primary inducers of tumor microenvironment. However, the proteome that can be exosomally transported from cancer cells to macrophages has not been sufficiently characterized so far. Here, we used colorectal cancer (CRC) exosomes to educate tumor-favorable macrophages. With a SILAC-based mass spectrometry strategy, we successfully traced the proteome transported from CRC exosomes to macrophages. Such a proteome primarily focused on promoting cytoskeleton rearrangement, which was biologically validated with multiple cell lines. We reproduced the exosomal transportation of functional vimentin as a proof-of-concept example. In addition, we found that some CRC exosomes could be recognized by macrophages via Fc receptors. Therefore, we revealed the active and necessary role of exosomes secreted from CRC cells to transform cancer-favorable macrophages, with the cytoskeleton-centric proteins serving as the top functional unit.

  7. Increases in cerebrospinal fluid caffeine concentration are associated with favorable outcome after severe traumatic brain injury in humans

    Science.gov (United States)

    Sachse, Kathleen T; Jackson, Edwin K; Wisniewski, Stephen R; Gillespie, Delbert G; Puccio, Ava M; Clark, Robert SB; Dixon, C Edward; Kochanek, Patrick M

    2013-01-01

    Caffeine, the most widely consumed psychoactive drug and a weak adenosine receptor antagonist, can be neuroprotective or neurotoxic depending on the experimental model or neurologic disorder. However, its contribution to pathophysiology and outcome in traumatic brain injury (TBI) in humans is undefined. We assessed serial cerebrospinal fluid (CSF) concentrations of caffeine and its metabolites (theobromine, paraxanthine, and theophylline) by high-pressure liquid chromatography/ultraviolet in 97 ventricular CSF samples from an established bank, from 30 adults with severe TBI. We prospectively selected a threshold caffeine level of ≥1 μmol/L (194 ng/mL) as clinically significant. Demographics, Glasgow Coma Scale (GCS) score, admission blood alcohol level, and 6-month dichotomized Glasgow Outcome Scale (GOS) score were assessed. Mean time from injury to initial CSF sampling was 10.77±3.13 h. On initial sampling, caffeine was detected in 24 of 30 patients, and the threshold was achieved in 9 patients. Favorable GOS was seen more often in patients with CSF caffeine concentration ≥ versus theobromine and paraxanthine were also associated with favorable outcome (P = 0.018 and 0.056, respectively). Caffeine and its metabolites are commonly detected in CSF in patients with severe TBI and in an exploratory assessment are associated with favorable outcome. We speculate that caffeine may be neuroprotective by long-term upregulation of adenosine A1 receptors or acute inhibition of A2a receptors. PMID:17684518

  8. Identification of Bexarotene as a PPARγ Antagonist with HDX

    Directory of Open Access Journals (Sweden)

    David P. Marciano

    2015-01-01

    Full Text Available The retinoid x receptors (RXRs are the pharmacological target of Bexarotene, an antineoplastic agent indicated for the treatment of cutaneous T cell lymphoma (CTCL. The RXRs form heterodimers with several nuclear receptors (NRs, including peroxisome proliferator-activated receptor gamma (PPARγ, to regulate target gene expression through cooperative recruitment of transcriptional machinery. Here we have applied hydrogen/deuterium exchange (HDX mass spectrometry to characterize the effects of Bexarotene on the conformational plasticity of the intact RXRα:PPARγ heterodimer. Interestingly, addition of Bexarotene to PPARγ in the absence of RXRα induced protection from solvent exchange, suggesting direct receptor binding. This observation was confirmed using a competitive binding assay. Furthermore, Bexarotene functioned as a PPARγ antagonist able to alter rosiglitazone induced transactivation in a cell based promoter:reporter transactivation assay. Together these results highlight the complex polypharmacology of lipophilic NR targeted small molecules and the utility of HDX for identifying and characterizing these interactions.

  9. Agomelatine, a MT1/MT2melatonergic receptor agonist with serotonin 5-HT2Creceptor antagonistic properties, suppresses Prevotella intermedia lipopolysaccharide-induced production of proinflammatory mediators in murine macrophages.

    Science.gov (United States)

    Hyeon, Jin-Yi; Choi, Eun-Young; Choe, So-Hui; Park, Hae Ryoun; Choi, Jeom-Il; Choi, In Soon; Kim, Sung-Jo

    2017-10-01

    This study was performed in an attempt to examine the influence of agomelatine in mitigating the generation of proinflammatory mediators in RAW264.7 murine macrophages exposed to lipopolysaccharide (LPS) obtained from Prevotella intermedia, a gram-negative anaerobic bacterium that is related with various types of periodontal diseases, and the molecular mechanisms behind its effects. LPS from P. intermedia strain ATCC 25611 was prepared employing the conventional phenol-water procedure. Conditioned culture media were analyzed for the levels of nitric oxide (NO), interleukin-1β (IL-1β) and IL-6. Real-time PCR analysis was carried out to determine the mRNA levels of inducible NO synthase (iNOS), IL-1β, IL-6 and SOCS1. Protein expression levels were evaluated by immunoblot test. NF-κB-dependent SEAP reporter assay was performed using a reporter cell line. DNA-binding activities of NF-κB subunits were analyzed utilizing the ELISA-based kits. Agomelatine was found to down-regulate significantly the generation of iNOS-derived NO, IL-1β and IL-6 as well as the expression of their mRNAs in cells activated with P. intermedia LPS. Agomelatine decreased NF-κB-dependent SEAP release caused by P. intermedia LPS. Agomelatine did not inhibit NF-κB transcription induced by LPS at the level of IκB-α degradation. Instead, LPS-induced nuclear translocation and DNA binding of NF-κB p50 subunit was blocked by agomelatine. P. intermedia LPS-elicited activation of STAT1 and STAT3 was reduced notably by co-treatment with agomelatine. Agomelatine showed a tendency to enhance mRNA level of SOCS1 in LPS-activated cells as well. Agomelatine merits further evaluation to reveal its usefulness on the host modulation of periodontal disease. Copyright © 2017 Elsevier Ltd. All rights reserved.

  10. Learning acceleration for gifted students: Favorable and unfavorable arguments

    OpenAIRE

    Rodrigues Maia-Pinto, Renata; Souza Fleith, Denise de

    2012-01-01

    This paper analyzes acceleration in education as a practice for meeting the educational needs of gifted students, and points out favorable and unfavorable arguments on the use of this practice. Acceleration is an educational practice consisting of several teaching strategies designed to encourage academically gifted students and reduce their time spent in school. It promotes faster learning by matching the curriculum to the student’s level of knowledge, interest and motivation. There are seve...

  11. ETA-receptor antagonists or allosteric modulators?

    DEFF Research Database (Denmark)

    De Mey, Jo G R; Compeer, Matthijs G; Lemkens, Pieter

    2011-01-01

    . In resistance arteries, the long-lasting contractile effects can only be partly and reversibly relaxed by low-molecular-weight ET(A) antagonists (ERAs). However, the neuropeptide calcitonin-gene-related peptide selectively terminates binding of ET1 to ET(A). We propose that ET1 binds polyvalently to ET......(A) and that ERAs and the physiological antagonist allosterically reduce ET(A) functions. Combining the two-state model and the two-domain model of GPCR function and considering receptor activation beyond agonist binding might lead to better anti-endothelinergic drugs. Future studies could lead to compounds...

  12. Menor valor: ¿oferta más favorable?

    Directory of Open Access Journals (Sweden)

    Iván Alirio Ramírez Rusinque

    2014-07-01

    Full Text Available La más importante transformación establecida por la Ley 1150 de 2007 en la contratación estatal radicó en la determinación del menor valor como la oferta más favorable para las entidades estatales, cuando se trate de la adquisición o suministro de bienes y servicios de características técnicas uniformes y de común utilización. Por ello, reviste de gran importancia realizar un análisis desde el punto de vista jurídico y normativo, que permita establecer si la mutación sufrida al concepto de oferta más favorable trajo consigo los fines perseguidos por la reforma, o en su defecto fue perjudicial la solución, al afectar el deber de selección objetiva, los principios de la contratación estatal de igualdad, eficacia, transparencia, planeación y equilibrio financiero del contrato y el principio constitucional de la libre competencia. Para de esta forma establecer si el modelo del menor valor como criterio de la oferta más favorable resulta eficiente jurídicamente en el campo de la contratación estatal, y si las reglas establecidas en la actualidad permiten el desarrollo armónico del sistema establecido por la Ley 1150 de 2007.

  13. Dynamics of urokinase receptor interaction with Peptide antagonists studied by amide hydrogen exchange and mass spectrometry

    DEFF Research Database (Denmark)

    Jørgensen, Thomas J D; Gårdsvoll, Henrik; Danø, Keld

    2004-01-01

    Using amide hydrogen exchange combined with electrospray ionization mass spectrometry, we have in this study determined the number of amide hydrogens on several peptides that become solvent-inaccessible as a result of their high-affinity interaction with the urokinase-type plasminogen activator...... receptor (uPAR). These experiments reveal that at least six out of eight amide hydrogens in a synthetic nine-mer peptide antagonist (AE105) become sequestered upon engagement in uPAR binding. Various uPAR mutants with decreased affinity for this peptide antagonist gave similar results, thereby indicating...... that deletion of the favorable interactions involving the side chains of these residues in uPAR does not affect the number of hydrogen bonds established by the main chain of the peptide ligand. The isolated growth factor-like domain (GFD) of the cognate serine protease ligand for uPAR showed 11 protected amide...

  14. Biaryls as potent, tunable dual neurokinin 1 receptor antagonists and serotonin transporter inhibitors.

    Science.gov (United States)

    Degnan, Andrew P; Tora, George O; Han, Ying; Rajamani, Ramkumar; Bertekap, Robert; Krause, Rudolph; Davis, Carl D; Hu, Joanna; Morgan, Daniel; Taylor, Sarah J; Krause, Kelly; Li, Yu-Wen; Mattson, Gail; Cunningham, Melissa A; Taber, Matthew T; Lodge, Nicholas J; Bronson, Joanne J; Gillman, Kevin W; Macor, John E

    2015-08-01

    Depression is a serious illness that affects millions of patients. Current treatments are associated with a number of undesirable side effects. Neurokinin 1 receptor (NK1R) antagonists have recently been shown to potentiate the antidepressant effects of serotonin-selective reuptake inhibitors (SSRIs) in a number of animal models. Herein we describe the optimization of a biaryl chemotype to provide a series of potent dual NK1R antagonists/serotonin transporter (SERT) inhibitors. Through the choice of appropriate substituents, the SERT/NK1R ratio could be tuned to afford a range of target selectivity profiles. This effort culminated in the identification of an analog that demonstrated oral bioavailability, favorable brain uptake, and efficacy in the gerbil foot tap model. Ex vivo occupancy studies with compound 58 demonstrated the ability to maintain NK1 receptor saturation (>88% occupancy) while titrating the desired level of SERT occupancy (11-84%) via dose selection. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Synthesis and evaluation of radioiodinated NPC 22009, a putative CRF receptor antagonist

    International Nuclear Information System (INIS)

    Balasubramanian, V.; Hiner, R.N.; Mavunkel, B.J.; Elliott, R.L.; Abreu, M.E.

    1992-01-01

    Several studies have suggested that corticotropin-releasing factor (CRF) plays a role in stress-related disorders such as anxiety, depression, anorexia nervosa and stress-induced immune suppression. Hence CRF antagonists have potential therapeutic utility. Recently the authors discovered that pyrazolones such as NPC 22009 and the corresponding disulfide behave as CRF antagonists in vitro with micromolar potency. To probe the nature of this CRF antagonism they developed a convenient synthesis of radioiodinated NPC 22009. Details of the synthesis and preliminary pharmacological studies are presented

  16. Antagonistic natural and sexual selection on wing shape in a scrambling damselfly.

    Science.gov (United States)

    Outomuro, David; Söderquist, Linus; Nilsson-Örtman, Viktor; Cortázar-Chinarro, María; Lundgren, Cecilia; Johansson, Frank

    2016-07-01

    Wings are a key trait underlying the evolutionary success of birds, bats, and insects. For over a century, researchers have studied the form and function of wings to understand the determinants of flight performance. However, to understand the evolution of flight, we must comprehend not only how morphology affects performance, but also how morphology and performance affect fitness. Natural and sexual selection can either reinforce or oppose each other, but their role in flight evolution remains poorly understood. Here, we show that wing shape is under antagonistic selection with regard to sexual and natural selection in a scrambling damselfly. In a field setting, natural selection (survival) favored individuals with long and slender forewings and short and broad hindwings. In contrast, sexual selection (mating success) favored individuals with short and broad forewings and narrow-based hindwings. Both types of selection favored individuals of intermediate size. These results suggest that individuals face a trade-off between flight energetics and maneuverability and demonstrate how natural and sexual selection can operate in similar directions for some wing traits, that is, wing size, but antagonistically for others, that is, wing shape. Furthermore, they highlight the need to study flight evolution within the context of species' mating systems and mating behaviors. © 2016 The Author(s).

  17. Functionalized Congeners of P2Y1 Receptor Antagonists:

    Energy Technology Data Exchange (ETDEWEB)

    de Castro, Sonia [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health; Maruoka, Hiroshi [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health; Hong, Kunlun [ORNL; Kilbey, II, S Michael [ORNL; Costanzi, Stefano [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health; Hechler, Béatrice [University of Strasbourg; Gachet, Christian [EFS-Alsace, Strasbourg, France; Harden, T. Kendall [University of North Carolina School of Medicine; Jacobson, Kenneth A. [National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health

    2010-01-01

    The P2Y{sub 1} receptor is a prothrombotic G protein-coupled receptor (GPCR) activated by ADP. Preference for the North (N) ring conformation of the ribose moiety of adenine nucleotide 3',5'-bisphosphate antagonists of the P2Y{sub 1} receptor was established by using a ring-constrained methanocarba (a bicyclo[3.1.0]hexane) ring as a ribose substitute. A series of covalently linkable N{sup 6}-methyl-(N)-methanocarba-2'-deoxyadenosine-3',5'-bisphosphates containing extended 2-alkynyl chains was designed, and binding affinity at the human (h) P2Y{sub 1} receptor determined. The chain of these functionalized congeners contained hydrophilic moieties, a reactive substituent, or biotin, linked via an amide. Variation of the chain length and position of an intermediate amide group revealed high affinity of carboxylic congener 8 (K{sub i} 23 nM) and extended amine congener 15 (K{sub i} 132 nM), both having a 2-(1-pentynoyl) group. A biotin conjugate 18 containing an extended {epsilon}-aminocaproyl spacer chain exhibited higher affinity than a shorter biotinylated analogue. Alternatively, click coupling of terminal alkynes of homologous 2-dialkynyl nucleotide derivatives to alkyl azido groups produced triazole derivatives that bound to the P2Y{sub 1} receptor following deprotection of the bisphosphate groups. The preservation of receptor affinity of the functionalized congeners was consistent with new P2Y{sub 1} receptor modeling and ligand docking. Attempted P2Y{sub 1} antagonist conjugation to PAMAM dendrimer carriers by amide formation or palladium-catalyzed reaction between an alkyne on the dendrimer and a 2-iodopurine-derivatized nucleotide was unsuccessful. A dialkynyl intermediate containing the chain length favored in receptor binding was conjugated to an azide-derivatized dendrimer, and the conjugate inhibited ADP-promoted human platelet aggregation. This is the first example of attaching a strategically functionalized P2Y receptor

  18. Molecular mechanisms of 5-HT(3) and NK(1) receptor antagonists in prevention of emesis.

    Science.gov (United States)

    Rojas, Camilo; Raje, Mithun; Tsukamoto, Takashi; Slusher, Barbara S

    2014-01-05

    Nausea and vomiting are major side effects of chemotherapy and one key reason for non-compliance with cancer treatment. The introduction of 5-HT3 receptor antagonists in the 1990s was a major advance in the prevention of acute emesis, and highlighted the critical role of serotonin in the emetic response. The next major advance in the treatment of chemotherapy induced nausea and vomiting (CINV) occurred in 2003 with the introduction of aprepitant, a tachykinin 1 (NK1) receptor antagonist. Aprepitant not only reduced acute emesis but also helped in the reduction of delayed emesis. Also in 2003, palonosetron, a second generation 5-HT3 receptor antagonist became available. Unlike the first generation 5-HT3 receptor antagonists, palonosetron demonstrated efficacy in preventing both acute and delayed emesis. This review focuses on the mechanism of action of 5-HT3 and NK1 receptor antagonists in acute and delayed CINV prevention. We discuss first, the medicinal chemistry that led to the discovery of these antagonists to underline their common structural features. Second, we discuss their performance in the clinic and what it tells us about the emetic response. Finally, we present recent mechanistic studies that help provide a rationale for efficacy differences between palonosetron and other 5-HT3 receptor antagonists in the clinic. In vitro and in vivo experiments have shown that palonosetron can inhibit substance P-mediated responses, presumably through its unique interactions with the 5-HT3 receptor. The crossroads of acute and delayed emesis seem to include interactions among the 5-HT3 and NK1 receptor signaling pathways and inhibitions of these interactions could lead to improved treatment of CINV. © 2013 Elsevier B.V. All rights reserved.

  19. CRTH2 antagonists in asthma: current perspectives

    Directory of Open Access Journals (Sweden)

    Singh D

    2017-12-01

    Full Text Available Dave Singh, Arjun Ravi, Thomas Southworth Division of Infection, Immunity and Respiratory Medicine, The Medicines Evaluation Unit, Manchester Academic Health Science Centre, Manchester University NHS Foundation Trust, The University of Manchester, Manchester, UK Abstract: Chemoattractant receptor-homologous molecule expressed on TH2 cells (CRTH2 binds to prostaglandin D2. CRTH2 is expressed on various cell types including eosinophils, mast cells, and basophils. CRTH2 and prostaglandin D2 are involved in allergic inflammation and eosinophil activation. Orally administered CRTH2 antagonists are in clinical development for the treatment of asthma. The biology and clinical trial data indicate that CRTH2 antagonists should be targeted toward eosinophilic asthma. This article reviews the clinical evidence for CRTH2 involvement in asthma pathophysiology and clinical trials of CRTH2 antagonists in asthma. CRTH2 antagonists could provide a practical alternative to biological treatments for patients with severe asthma. Future perspectives for this class of drug are considered, including the selection of the subgroup of patients most likely to show a meaningful treatment response. Keywords: CRTH2, clinical trial, eosinophilic asthma, prostaglandin D2

  20. Carbon adaptation influence the antagonistic ability of ...

    African Journals Online (AJOL)

    Influences of carbon adaptation on antagonistic activities of three Pseudomonas aeruginosa strains V4, V7 and V10 against Fusarium oxysporum f. sp. melonis were determined in this study. Results from this study showed that the P. aeruginosa strains and their adapted strains significantly inhibited the growth of mycelium ...

  1. Calcium antagonists for aneurysmal subarachnoid haemorrhage

    NARCIS (Netherlands)

    Rinkel, G. J. E.; Feigin, V. L.; Algra, A.; van den Bergh, W. M.; Vermeulen, M.; van Gijn, J.

    2005-01-01

    BACKGROUND: Secondary ischaemia is a frequent cause of poor outcome in patients with subarachnoid haemorrhage (SAH). Its pathogenesis has not been elucidated yet, but may be related to vasospasm. Experimental studies have indicated that calcium antagonists can prevent or reverse vasospasm and have

  2. Antagonistic properties of microogranisms associated with cassava ...

    African Journals Online (AJOL)

    The antagonistic properties of indigenous microflora from cassava starch, flour and grated cassava were investigated using the conventional streak, novel ring and well diffusion methods. Antagonism was measured by zone of inhibition between the fungal plug and bacterial streak/ring. Bacillus species were more effective ...

  3. Bitter melon: antagonist to cancer.

    Science.gov (United States)

    Nerurkar, Pratibha; Ray, Ratna B

    2010-06-01

    The incidence of cancer is increasing worldwide, in spite of substantial progress in the development of anti-cancer therapies. One approach to control cancer could be its prevention by diet, which inhibits one or more neoplastic events and reduces cancer risk. Dietary compounds offer great potential in the fight against cancer by inhibiting the carcinogenesis process through the regulation of cell homeostasis and cell-death machineries. For centuries, Ayurveda (Indian traditional medicine) has recommended the use of bitter melon (Momordica charantia) as a functional food to prevent and treat diabetes and associated complications. It is noteworthy to mention that bitter melon extract has no-to-low side effects in animals as well as in humans. The anti-tumor activity of bitter melon has recently begun to emerge. This review focuses on recent advancements in cancer chemopreventive and anti-cancer efficacy of bitter melon and its active constituents. Several groups of investigators have reported that treatment of bitter-melon-related products in a number of cancer cell lines induces cell cycle arrest and apoptosis without affecting normal cell growth. Therefore, the effect of bitter melon should be beneficial for health, and use of the non-modified dietary product is cost effective.

  4. Plant growth-promoting rhizobacteria (PGPR: their potential as antagonists and biocontrol agents

    Directory of Open Access Journals (Sweden)

    Anelise Beneduzi

    2012-01-01

    Full Text Available Bacteria that colonize plant roots and promote plant growth are referred to as plant growth-promoting rhizobacteria (PGPR. PGPR are highly diverse and in this review we focus on rhizobacteria as biocontrol agents. Their effects can occur via local antagonism to soil-borne pathogens or by induction of systemic resistance against pathogens throughout the entire plant. Several substances produced by antagonistic rhizobacteria have been related to pathogen control and indirect promotion of growth in many plants, such as siderophores and antibiotics. Induced systemic resistance (ISR in plants resembles pathogen-induced systemic acquired resistance (SAR under conditions where the inducing bacteria and the challenging pathogen remain spatially separated. Both types of induced resistance render uninfected plant parts more resistant to pathogens in several plant species. Rhizobacteria induce resistance through the salicylic acid-dependent SAR pathway, or require jasmonic acid and ethylene perception from the plant for ISR. Rhizobacteria belonging to the genera Pseudomonas and Bacillus are well known for their antagonistic effects and their ability to trigger ISR. Resistance-inducing and antagonistic rhizobacteria might be useful in formulating new inoculants with combinations of different mechanisms of action, leading to a more efficient use for biocontrol strategies to improve cropping systems.

  5. Recent progress in the development of small-molecule glucagon receptor antagonists.

    Science.gov (United States)

    Sammons, Matthew F; Lee, Esther C Y

    2015-10-01

    The endocrine hormone glucagon stimulates hepatic glucose output via its action at the glucagon receptor (GCGr) in the liver. In the diabetic state, dysregulation of glucagon secretion contributes to abnormally elevated hepatic glucose output. The inhibition of glucagon-induced hepatic glucose output via antagonism of the GCGr using small-molecule ligands is a promising mechanism for improving glycemic control in the diabetic state. Clinical data evaluating the therapeutic potential of small-molecule GCGr antagonists is currently emerging. Recently disclosed clinical data demonstrates the potential efficacy and possible therapeutic limitations of small-molecule GCGr antagonists. Recent pre-clinical work on the development of GCGr antagonists is also summarized. Copyright © 2015 Elsevier Ltd. All rights reserved.

  6. Apoptosis induction by doxazosin and other quinazoline alpha(1)-adrenoceptor antagonists: a new mechanism for cancer treatment?

    NARCIS (Netherlands)

    Kyprianou, Natasha; Vaughan, Taylor B.; Michel, Martin C.

    2009-01-01

    Doxazosin and related, quinazoline-based alpha(1)-adrenoceptor antagonists can induce apoptosis in prostate and various other normal, benign, smooth muscle, endothelial and malignant cells. Such apoptosis-inducing effects occur independently of alpha(1)-adrenoceptor antagonism and typically require

  7. Antagonist-Elicited Cannabis Withdrawal in Humans

    Science.gov (United States)

    Gorelick, David A.; Goodwin, Robert S.; Schwilke, Eugene; Schwope, David M.; Darwin, William D.; Kelly, Deanna L.; McMahon, Robert P.; Liu, Fang; Ortemann-Renon, Catherine; Bonnet, Denis; Huestis, Marilyn A.

    2013-01-01

    Cannabinoid CB1 receptor antagonists have potential therapeutic benefits, but antagonist-elicited cannabis withdrawal has not been reported in humans. Ten male daily cannabis smokers received 8 days of increasingly frequent 20-mg oral Δ9-tetrahydrocannabinol (THC) dosages (40–120 mg/d) around-the-clock to standardize cannabis dependence while residing on a closed research unit. On the ninth day, double-blind placebo or 20- (suggested therapeutic dose) or 40-mg oral rimonabant, a CB1-cannabinoid receptor antagonist, was administered. Cannabis withdrawal signs and symptoms were assessed before and for 23.5 hours after rimonabant. Rimonabant, THC, and 11-hydroxy-THC plasma concentrations were quantified by mass spectrometry. The first 6 subjects received 20-mg rimonabant (1 placebo); the remaining 4 subjects received 40-mg rimonabant (1 placebo). Fourteen subjects enrolled; 10 completed before premature termination because of withdrawal of rimonabant from clinical development. Three of 5 subjects in the 20-mg group, 1 of 3 in the 40-mg group, and none of 2 in the placebo group met the prespecified withdrawal criterion of 150% increase or higher in at least 3 visual analog scales for cannabis withdrawal symptoms within 3 hours of rimonabant dosing. There were no significant associations between visual analog scale, heart rate, or blood pressure changes and peak rimonabant plasma concentration, area-under-the-rimonabant-concentration-by-time curve (0–8 hours), or peak rimonabant/THC or rimonabant/(THC + 11-hydroxy-THC) plasma concentration ratios. In summary, prespecified criteria for antagonist-elicited cannabis withdrawal were not observed at the 20- or 40-mg rimonabant doses. These data do not preclude antagonist-elicited withdrawal at higher rimonabant doses. PMID:21869692

  8. Antagonist-elicited cannabis withdrawal in humans.

    Science.gov (United States)

    Gorelick, David A; Goodwin, Robert S; Schwilke, Eugene; Schwope, David M; Darwin, William D; Kelly, Deanna L; McMahon, Robert P; Liu, Fang; Ortemann-Renon, Catherine; Bonnet, Denis; Huestis, Marilyn A

    2011-10-01

    Cannabinoid CB1 receptor antagonists have potential therapeutic benefits, but antagonist-elicited cannabis withdrawal has not been reported in humans. Ten male daily cannabis smokers received 8 days of increasingly frequent 20-mg oral Δ⁹-tetrahydrocannabinol (THC) dosages (40-120 mg/d) around-the-clock to standardize cannabis dependence while residing on a closed research unit. On the ninth day, double-blind placebo or 20- (suggested therapeutic dose) or 40-mg oral rimonabant, a CB1-cannabinoid receptor antagonist, was administered. Cannabis withdrawal signs and symptoms were assessed before and for 23.5 hours after rimonabant. Rimonabant, THC, and 11-hydroxy-THC plasma concentrations were quantified by mass spectrometry. The first 6 subjects received 20-mg rimonabant (1 placebo); the remaining 4 subjects received 40-mg rimonabant (1 placebo). Fourteen subjects enrolled; 10 completed before premature termination because of withdrawal of rimonabant from clinical development. Three of 5 subjects in the 20-mg group, 1 of 3 in the 40-mg group, and none of 2 in the placebo group met the prespecified withdrawal criterion of 150% increase or higher in at least 3 visual analog scales for cannabis withdrawal symptoms within 3 hours of rimonabant dosing. There were no significant associations between visual analog scale, heart rate, or blood pressure changes and peak rimonabant plasma concentration, area-under-the-rimonabant-concentration-by-time curve (0-8 hours), or peak rimonabant/THC or rimonabant/(THC + 11-hydroxy-THC) plasma concentration ratios. In summary, prespecified criteria for antagonist-elicited cannabis withdrawal were not observed at the 20- or 40-mg rimonabant doses. These data do not preclude antagonist-elicited withdrawal at higher rimonabant doses.

  9. More evidence in favor of light dark matter particles?

    International Nuclear Information System (INIS)

    Boehm, Celine; Ascasibar, Yago

    2004-01-01

    In a previous work, it was found that the light dark matter scenario could be a possible explanation to the 511 keV emission line detected at the center of our galaxy. Here, we show that hints of this scenario may also have been discovered in particle physics experiments. This could explain the discrepancy between the measurement of the fine structure constant and the value referenced in the CODATA. Finally, our results indicate that some of the light dark matter features could be tested in accelerators. Their discovery might favor N=2 supersymmetry

  10. Combining elements from two antagonists of formyl peptide receptor 2 generates more potent peptidomimetic antagonists

    DEFF Research Database (Denmark)

    Skovbakke, Sarah Line; Holdfeldt, Andre; Nielsen, Christina

    2017-01-01

    Structural optimization of a peptidomimetic antagonist of formyl peptide receptor 2 (FPR2) was explored by an approach involving combination of elements from the two most potent FPR2 antagonists described: a Rhodamine B-conjugated 10-residue gelsonin-derived peptide (i.e., PBP10, Rh......B-QRLFQVKGRR-OH) and the palmitoylated α-peptide/β-peptoid hybrid Pam-(Lys-βNspe)6-NH2. This generated an array of hybrid compounds from which a new subclass of receptor-selective antagonists was identified. The most potent representatives displayed activity in the low nanomolar range. The resulting stable and potent FPR2-selective...... antagonists (i.e., RhB-(Lys-βNphe)n-NH2; n = 4–6) are expected to become valuable tools in further elucidation of the physiological role of FPR2 in health and disease....

  11. Orexin 1 receptor antagonists in compulsive behavior and anxiety: possible therapeutic use.

    Science.gov (United States)

    Merlo Pich, Emilio; Melotto, Sergio

    2014-01-01

    Fifteen years after the discovery of hypocretin/orexin a large body of evidence has been collected supporting its critical role in the modulation of several regulatory physiological functions. While reduced levels of hypocretin/orexin were initially associated with narcolepsy, increased levels have been linked in recent years to pathological states of hypervigilance and, in particular, to insomnia. The filing to FDA of the dual-activity orexin receptor antagonist (DORA) suvorexant for the indication of insomnia further corroborates the robustness of such evidences. However, as excessive vigilance is also typical of anxiety and panic episodes, as well as of abstinence and craving in substance misuse disorders. In this review we briefly discuss the evidence supporting the development of hypocretin/orexin receptor 1 (OX1) antagonists for these indications. Experiments using the OX1 antagonist SB-334867 and mutant mice have involved the OX1 receptor in mediating the compulsive reinstatement of drug seeking for ethanol, nicotine, cocaine, cannabinoids and morphine. More recently, data have been generated with the novel selective OX1 antagonists GSK1059865 and ACT-335827 on behavioral and cardiovascular response to stressors and panic-inducing agents in animals. Concluding, while waiting for pharmacologic data to become available in humans, risks and benefits for the development of an OX1 receptor antagonist for Binge Eating and Anxiety Disorders are discussed.

  12. Progress in the development of oxytocin antagonists for use in preterm labor.

    Science.gov (United States)

    Williams, P D; Bock, M G; Evans, B E; Freidinger, R M; Pettibone, D J

    1998-01-01

    There is currently a need for new therapeutic agents for treating preterm labor which could offer improved safety and efficacy beyond what has been achieved with the widely employed beta-mimetics. In this regard, the longstanding hypothesis of oxytocin receptor blockade as representing a potentially more selective method of tocolysis has continued to gain support from results obtained in clinical studies with the peptide oxytocin antagonist, atosiban. Our laboratory has focussed on the identification of non-peptide oxytocin antagonists with properties suitable for both oral and intravenous administration. We have previously described the development of potent, camphor-based oxytocin antagonists, including L-368,899 which entered phase I human studies. More recently we have pursued a new structural class of oxytocin antagonists based on the 1-(N-benzoylpiperidin-4-yl)-4H-3,1-benzoxazin-2(1H)-one template. L-372,662 is a new member of this structural class and in our preclinical assays possesses an attractive overall profile from the standpoint of human oxytocin receptor affinity (Ki = 4.9 nM), human oxytocin vs. vasopressin receptor selectivity (> 500-fold), potency as an antagonist of oxytocin-induced uterine contractions in late gestation pregnant rhesus monkeys (AD50 = 36 micrograms/kg), oral bioavailability (F = 90% in dogs), and aqueous solubility (10 mg/mL).

  13. Orexin 1 receptor antagonists in compulsive behaviour and anxiety: possible therapeutic use.

    Directory of Open Access Journals (Sweden)

    Emilio eMerlo-Pich

    2014-02-01

    Full Text Available Fifteen years after the discovery of hypocretin/orexin a large body of evidence has been collected supporting its critical role in the modulation of several regulatory physiological functions. While reduced levels of hypocretin/orexin were early on associated with narcolepsy, increased levels have been linked in recent years to pathological states of hypervigilance and, in particular, to insomnia. The filing to FDA of the dual-activity orexin receptor antagonist (DORA suvorexant for the indication of insomnia further corroborates the robustness of such evidences. However, as excessive vigilance is also typical of anxiety and panic episodes, as well as of abstinence and craving in substance misuse disorders, in this review we briefly discuss the evidence supporting the development of hypocretin/orexin receptor 1 (OX1 antagonists for these indications. Experiments using the OX1 antagonist SB-334867 and mutant mice have involved the OX1 receptor in mediating the compulsive reinstatement of drug seeking for ethanol, nicotine, cocaine, cannabinoids and morphine. More recently, data have been generated with the novel selective OX1 antagonists GSK1059865 and ACT-335827 on behavioural and cardiovascular response to stressors and panic-inducing agents in animals. Concluding, while waiting for pharmacologic data to become available in humans, risks and benefits for the development of an OX1 receptor antagonist for Binge Eating and Anxiety Disorders are discussed.

  14. Structure-Based Design of a Periplasmic Binding Protein Antagonist that Prevents Domain Closure

    Energy Technology Data Exchange (ETDEWEB)

    Borrok, M. Jack; Zhu, Yimin; Forest, Katrina T.; Kiessling, Laura L.; (UW)

    2009-07-31

    Many receptors undergo ligand-induced conformational changes to initiate signal transduction. Periplasmic binding proteins (PBPs) are bacterial receptors that exhibit dramatic conformational changes upon ligand binding. These proteins mediate a wide variety of fundamental processes including transport, chemotaxis, and quorum sensing. Despite the importance of these receptors, no PBP antagonists have been identified and characterized. In this study, we identify 3-O-methyl-D-glucose as an antagonist of glucose/galactose-binding protein and demonstrate that it inhibits glucose chemotaxis in E. coli. Using small-angle X-ray scattering and X-ray crystallography, we show that this antagonist acts as a wedge. It prevents the large-scale domain closure that gives rise to the active signaling state. Guided by these results and the structures of open and closed glucose/galactose-binding protein, we designed and synthesized an antagonist composed of two linked glucose residues. These findings provide a blueprint for the design of new bacterial PBP inhibitors. Given the key role of PBPs in microbial physiology, we anticipate that PBP antagonists will have widespread uses as probes and antimicrobial agents.

  15. Behavioral, biological, and chemical perspectives on targeting CRF1 receptor antagonists to treat alcoholism

    Science.gov (United States)

    Zorrilla, Eric P.; Heilig, Markus; de Wit, Harriet; Shaham, Yavin

    2013-01-01

    Background Alcohol use disorders are chronic disabling conditions for which existing pharmacotherapies have only modest efficacy. In the present review, derived from the 2012 Behavior, Biology and Chemistry “Translational Research in Addiction” symposium, we summarize the anti-relapse potential of corticotropin-releasing factor type 1 (CRF1) receptor antagonists to reduce negative emotional symptoms of acute and protracted alcohol withdrawal and stress-induced relapse to alcohol seeking. Methods We review the biology of CRF1 systems, the activity of CRF1 receptor antagonists in animal models of anxiolytic and antidepressant activity, and experimental findings in alcohol addiction models. We also update the clinical trial status of CRF1 receptor antagonists, including pexacerfont (BMS-562086), emicerfont (GW876008), verucerfont (GSK561679), CP316311, SSR125543A, R121919/NBI30775, R317573/19567470/CRA5626, and ONO-2333Ms. Finally, we discuss the potential heterogeneity and pharmacogenomics of CRF1 receptor pharmacotherapy for alcohol dependence. Results The evidence suggests that brain penetrant-CRF1 receptor antagonists have therapeutic potential for alcohol dependence. Lead compounds with clinically desirable pharmacokinetic properties now exist, and longer receptor residence rates (i.e., slow dissociation) may predict greater CRF1 receptor antagonist efficacy. Functional variants in genes that encode CRF system molecules, including polymorphisms in Crhr1 (rs110402, rs1876831, rs242938) and Crhbp genes (rs10055255, rs3811939) may promote alcohol seeking and consumption by altering basal or stress-induced CRF system activation. Conclusions Ongoing clinical trials with pexacerfont and verucerfont in moderately to highly severe dependent anxious alcoholics may yield insight as to the role of CRF1 receptor antagonists in a personalized medicine approach to treat drug or alcohol dependence. PMID:23294766

  16. Evodiamine as a novel antagonist of aryl hydrocarbon receptor

    International Nuclear Information System (INIS)

    Yu, Hui; Tu, Yongjiu; Zhang, Chun; Fan, Xia; Wang, Xi; Wang, Zhanli; Liang, Huaping

    2010-01-01

    Research highlights: → Evodiamine interacted with the AhR. → Evodiamine inhibited the specific binding of [ 3 H]-TCDD to the AhR. → Evodiamine acts as an antagonist of the AhR. -- Abstract: Evodiamine, the major bioactive alkaloid isolated from Wu-Chu-Yu, has been shown to interact with a wide variety of proteins and modify their expression and activities. In this study, we investigated the interaction between evodiamine and the aryl hydrocarbon receptor (AhR). Molecular modeling results revealed that evodiamine directly interacted with the AhR. Cytosolic receptor binding assay also provided the evidence that evodiamine could interact with the AhR with the K i value of 28.4 ± 4.9 nM. In addition, we observed that evodiamine suppressed the 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) induced nuclear translocation of the AhR and the expression of CYP1A1 dose-dependently. These results suggested that evodiamine was able to bind to the AhR as ligand and exhibit antagonistic effects.

  17. Discovery of Novel Proline-Based Neuropeptide FF Receptor Antagonists.

    Science.gov (United States)

    Nguyen, Thuy; Decker, Ann M; Langston, Tiffany L; Mathews, Kelly M; Siemian, Justin N; Li, Jun-Xu; Harris, Danni L; Runyon, Scott P; Zhang, Yanan

    2017-10-18

    The neuropeptide FF (NPFF) system has been implicated in a number of physiological processes including modulating the pharmacological activity of opioid analgesics and several other classes of drugs of abuse. In this study, we report the discovery of a novel proline scaffold with antagonistic activity at the NPFF receptors through a high throughput screening campaign using a functional calcium mobilization assay. Focused structure-activity relationship studies on the initial hit 1 have resulted in several analogs with calcium mobilization potencies in the submicromolar range and modest selectivity for the NPFF1 receptor. Affinities and potencies of these compounds were confirmed in radioligand binding and functional cAMP assays. Two compounds, 16 and 33, had good solubility and blood-brain barrier permeability that fall within the range of CNS permeant candidates without the liability of being a P-glycoprotein substrate. Finally, both compounds reversed fentanyl-induced hyperalgesia in rats when administered intraperitoneally. Together, these results point to the potential of these proline analogs as promising NPFF receptor antagonists.

  18. Predicting response to opiate antagonists and placebo in the treatment of pathological gambling.

    Science.gov (United States)

    Grant, Jon E; Kim, Suck Won; Hollander, Eric; Potenza, Marc N

    2008-11-01

    Although opiate antagonists have shown promise in the treatment of pathological gambling (PG), individual responses vary. No studies have systematically examined predictors of medication treatment outcome in PG. Understanding clinical variables related to treatment outcome should help generate treatment algorithms for PG. We sought to identify clinical variables associated with treatment outcome in PG subjects receiving opiate antagonists. Two hundred eighty-four subjects [137 (48.2%) women] with DSM-IV PG were treated in one of two double-blind placebo-controlled trials (16 weeks of nalmefene or 18 weeks of naltrexone). Gambling severity was assessed with the Yale Brown Obsessive Compulsive Scale Modified for Pathological Gambling (PG-YBOCS) with positive response defined as > or =35% reduction in PG-YBOCS score for at least 1 month by study endpoint. Depression, anxiety, and psychosocial functioning were included in stepwise logistic regression analyses designed to identify clinical factors independently associated with treatment response. The clinical variable most strongly associated with a positive response to an opiate antagonist was a positive family history of alcoholism (p = 0.006). Among individuals receiving higher doses of opiate antagonists (i.e., nalmefene 50 or 100 mg/day or naltrexone 100 or 150 mg/day), intensity of gambling urges (PG-YBOCS urge subscale) was associated with a positive response on a trend level (p = 0.036). Among individuals receiving placebo, younger age was associated, on a trend level, with positive treatment outcome (p = 0.012). A family history of alcoholism appears to predict response to an opiate antagonist in PG. Future research is needed to identify specific factors (e.g., genetic) mediating favorable responses.

  19. Similarities and differences between calcium antagonists: pharmacological aspects

    NARCIS (Netherlands)

    van Zwieten, P. A.; Pfaffendorf, M.

    1993-01-01

    Characteristics of three different calcium antagonist groups: Most important calcium antagonists used to treat cardiovascular disease belong to one of three main groups, phenylalkylamines, dihydropyridines and benzothiazepines. The best known drug in each group is verapamil, nifedipine and

  20. Protective effects of calcium antagonists in different organs and tissues

    NARCIS (Netherlands)

    van Zwieten, P. A.

    1993-01-01

    The therapeutic efficacy of calcium antagonists in ischemic disorders of various tissues is attributed to vasodilator and antivasoconstrictor activities. A direct, energy-conserving, antiischemic effect of certain calcium antagonists has been claimed repeatedly by basic scientists. The clinical

  1. 2-Heteroaryl Benzimidazole Derivatives as Melanin Concentrating Hormone Receptor 1 (MCH-R1) Antagonists

    Energy Technology Data Exchange (ETDEWEB)

    Lim, Chae Jo; Kim, Jeong Young; Lee, Byung Ho; Oh, Kwangseok; Yi, Kyu Yang [Korea Research Institute of Chemical Technology, Daejeon (Korea, Republic of)

    2013-08-15

    A novel series of 2-heteroaryl substituted benzimidazole derivatives, containing the piperidinylphenyl acetamide group at the 1-position, were synthesized and evaluated as MCH-R1 antagonists. Extensive SAR investigation probing the effects of C-2 heteroaryl group led to the identification of 2-[2-(pyridin-3-yl)ethyl] analog 3o, which exhibits highly potent MCH-R1 binding activity with an IC{sub 50} value of 1 nM. This substance 3o also has low hERG binding activity, good metabolic stability, and favorable pharmacokinetic properties.

  2. Donepezil regulates energy metabolism and favors bone mass accrual.

    Science.gov (United States)

    Eimar, Hazem; Alebrahim, Sharifa; Manickam, Garthiga; Al-Subaie, Ahmed; Abu-Nada, Lina; Murshed, Monzur; Tamimi, Faleh

    2016-03-01

    The autonomous nervous system regulates bone mass through the sympathetic and parasympathetic arms. The sympathetic nervous system (SNS) favors bone loss whereas the parasympathetic nervous system (PNS) promotes bone mass accrual. Donepezil, a central-acting cholinergic agonist, has been shown to down-regulate SNS and up-regulate PNS signaling tones. Accordingly, we hypothesize that the use of donepezil could have beneficial effects in regulating bone mass. To test our hypothesis, two groups of healthy female mice were treated either with donepezil or saline. Differences in body metabolism and bone mass of the treated groups were compared. Body and visceral fat weights as well as serum leptin level were increased in donepezil-treated mice compared to control, suggesting that donepezil effects on SNS influenced metabolic activity. Donepezil-treated mice had better bone quality than controls due to a decrease in osteoclasts number. These results indicate that donepezil is able to affect whole body energy metabolism and favors bone mass in young female WT mice. Copyright © 2015 Elsevier Inc. All rights reserved.

  3. Is there a relationship between patient satisfaction and favorable outcomes?

    Science.gov (United States)

    Kennedy, Gregory D; Tevis, Sarah E; Kent, K Craig

    2014-10-01

    Patient satisfaction with the health care experience has become a top priority for Centers for Medicare and Medicaid Services. With resources and efforts directed at patient satisfaction, we evaluated whether high patient satisfaction measured by HCAHPS (Hospital Consumer Assessment of Healthcare Providers and Systems) surveys correlates with favorable outcomes. Medical centers were identified from the University HealthSystem Consortium database from 2011 to 2012. Variables included hospital characteristics, process measure compliance, and surgical outcomes. Chi-squared analysis was used to evaluate for variables associated with high patient satisfaction (defined as hospitals that scored above the 50th percentile of top box scores). We identified 171 hospitals with complete data. The following variables were significantly associated with high overall patient satisfaction: large hospitals, high surgical volume, and low mortality (P patient satisfaction. Low mortality index was consistently found to be associated with high satisfaction across 9 of 10 HCAHPS domains. We found that hospital size, surgical volume, and low mortality were associated with high overall patient satisfaction. However, with the exception of low mortality, favorable surgical outcomes were not consistently associated with high HCAHPS scores. With existing satisfaction surveys, we conclude that factors outside of surgical outcomes appear to influence patients' perceptions of their care.

  4. Partial to complete antagonism by putative antagonists at the wild-type α2C-adrenoceptor based on kinetic analyses of agonist : antagonist interactions

    Science.gov (United States)

    Pauwels, Petrus J; Colpaert, Francis C

    2000-01-01

    Activation of the recombinant human α2C-adrenoceptor (α2C AR) by (−)-adrenaline in CHO-K1 cells transiently co-expressing a chimeric Gαq/i1 protein induced a rapid, transient Ca2+ response with a high-magnitude followed by a low-magnitude phase which continued throughout the recorded time period (15 min). Activation of the α2C AR by various α2 AR agonists revealed the following rank order of high-magnitude Ca2+ response [Emax (%) versus 10 μM (−)-adrenaline]: UK 14304 (102±4)=talipexole (101±3)=(−)-adrenaline (100)=d-medetomidine (98±1)>oxymetazoline (81±4)⋍clonidine (75±5). The methoxy- (RX 821002) and ethoxy-derivatives (RX 811059) of idazoxan and the dexefaroxan analogue atipamezole were fully effective as antagonists of both the high- and the low-magnitude Ca2+ response. However, though acting as full antagonists of the high-magnitude response, the further putative α2 AR antagonists idazoxan (27%), SKF 86466 (29%) and dexefaroxan (59%) reversed the low-magnitude response only partially. In conclusion, kinetic analyses of agonist : antagonist interactions at the α2C AR demonstrate a wide spectrum of partial to complete antagonism of the low-magnitude Ca2+ response for structurally related α2 AR ligands. PMID:11090111

  5. The relative potency of inverse opioid agonists and a neutral opioid antagonist in precipitated withdrawal and antagonism of analgesia and toxicity.

    Science.gov (United States)

    Sirohi, Sunil; Dighe, Shveta V; Madia, Priyanka A; Yoburn, Byron C

    2009-08-01

    Opioid antagonists can be classified as inverse agonists and neutral antagonists. In the opioid-dependent state, neutral antagonists are significantly less potent in precipitating withdrawal than inverse agonists. Consequently, neutral opioid antagonists may offer advantages over inverse agonists in the management of opioid overdose. In this study, the relative potency of three opioid antagonists to block opioid analgesia and toxicity and precipitate withdrawal was examined. First, the potency of two opioid inverse agonists (naltrexone and naloxone) and a neutral antagonist (6beta-naltrexol) to antagonize fentanyl-induced analgesia and lethality was determined. The order of potency to block analgesia was naltrexone > naloxone > 6beta-naltrexol (17, 4, 1), which was similar to that to block lethality (13, 2, 1). Next, the antagonists were compared using withdrawal jumping in fentanyl-dependent mice. The order of potency to precipitate withdrawal jumping was naltrexone > naloxone 6beta-naltrexol (1107, 415, 1). The relative potencies to precipitate withdrawal for the inverse agonists compared with the neutral antagonist were dramatically different from that for antagonism of analgesia and lethality. Finally, the effect of 6beta-naltrexol pretreatment on naloxone-precipitated jumping was determined in morphine and fentanyl-dependent mice. 6beta-Naltrexol pretreatment decreased naloxone precipitated withdrawal, indicating that 6beta-naltrexol is a neutral antagonist. These data demonstrate that inverse agonists and neutral antagonists have generally comparable potencies to block opioid analgesia and lethality, whereas the neutral opioid antagonist is substantially less potent in precipitating opioid withdrawal. These results support suggestions that neutral antagonists may have advantages over inverse agonists in the management of opioid overdose.

  6. Discovery of novel N-aryl piperazine CXCR4 antagonists.

    Science.gov (United States)

    Zhao, Huanyu; Prosser, Anthony R; Liotta, Dennis C; Wilson, Lawrence J

    2015-11-01

    A novel series of CXCR4 antagonists with substituted piperazines as benzimidazole replacements is described. These compounds showed micromolar to nanomolar potency in CXCR4-mediated functional and HIV assays, namely inhibition of X4 HIV-1(IIIB) virus in MAGI-CCR5/CXCR4 cells and inhibition of SDF-1 induced calcium release in Chem-1 cells. Preliminary SAR investigations led to the identification of a series of N-aryl piperazines as the most potent compounds. Results show SAR that indicates type and position of the aromatic ring, as well as type of linker and stereochemistry are significant for activity. Profiling of several lead compounds showed that one (49b) reduced susceptibility towards CYP450 and hERG, and the best overall profile when considering both SDF-1 and HIV potencies (6-20 nM). Copyright © 2015 Elsevier Ltd. All rights reserved.

  7. The dual orexin receptor antagonist TCS1102 does not affect reinstatement of nicotine-seeking.

    Directory of Open Access Journals (Sweden)

    Shaun Yon-Seng Khoo

    Full Text Available The orexin/hypocretin system is important for appetitive motivation towards multiple drugs of abuse, including nicotine. Both OX1 and OX2 receptors individually have been shown to influence nicotine self-administration and reinstatement. Due to the increasing clinical use of dual orexin receptor antagonists in the treatment of disorders such as insomnia, we examined whether a dual orexin receptor antagonist may also be effective in reducing nicotine seeking. We tested the effect of intracerebroventricular (i.c.v. administration of the potent and selective dual orexin receptor antagonist TCS1102 on orexin-A-induced food self-administration, nicotine self-administration and reinstatement of nicotine-seeking in rats. Our results show that 30 μg of TCS1102 i.c.v. abolishes orexin-A-induced increases in food self-administration but does not reduce nicotine self-administration. Neither i.c.v. 10 μg nor 30 μg of TCS1102 reduced compound reinstatement after short-term (15 days self-administration nicotine, but 30 μg transiently reduced cue/nicotine compound reinstatement after chronic self-administration (29 days. These results indicate that TCS1102 has no substantial effect on motivation for nicotine seeking following chronic self-administration and no effect after shorter periods of intake. Orexin receptor antagonists may therefore have little clinical utility against nicotine addiction.

  8. [Communication with patients in palliative care: favoring cheerfulness and optimism].

    Science.gov (United States)

    de Araújo, Monica Martins Trovo; da Silva, Maria Júlia Paes

    2007-12-01

    The objective of this study was to know the expectations of patients who are in palliative care regarding communication with the nursing team. The data were collected during the first semester of 2005 through half-structured interviews among 39 oncological patients with no healing prognosis subjected to palliative chemotherapy in a hospital institution of the city of São Paulo. After transcription of the speeches, the data were analyzed according to the methodology of content analysis. From the interviewees' speeches four categories emerged. Interpersonal communication proved to be an important attribution to palliative care, with particular attention given to the professional's nonverbal signs for establishing a link of trust, the need for a compassionate presence, the desire not to focus the interaction and the relationship only on the disease and on death and to concentrate instead on cheerful verbal communication favoring optimism and good humor.

  9. 5-HT2A receptor antagonists inhibit hepatic stellate cell activation and facilitate apoptosis.

    Science.gov (United States)

    Kim, Dong Chan; Jun, Dae Won; Kwon, Young Il; Lee, Kang Nyeong; Lee, Hang Lak; Lee, Oh Young; Yoon, Byung Chul; Choi, Ho Soon; Kim, Eun Kyung

    2013-04-01

    5-hydroxytryptamine (5-HT) receptors are upregulated in activated hepatic stellate cells (HSCs), and are therefore thought to play an important role in their activation. The aim of this study was to determine whether 5-HT2A receptor antagonists affect the activation or apoptosis of HSCs in vitro and/or in vivo. For the in vitro experiments, the viability, apoptosis and wound healing ability of LX-2 cells were examined after treatment with various 5-HT2A receptor antagonists. Levels of HSC activation markers (procollagen type I, α-SMA, TGF-β and Smad 2/3) were measured. For in vivo experiments, rats were divided into three groups: (i) a control group, (ii) a disease group, in which cirrhosis was induced by thioacetamide (iii) a treatment group, in which cirrhosis was induced and a 5-HT2A receptor antagonist (sarpogrelate, 30 mg/kg) was administered. 5-HT2A , but not 5-HT2B receptor mRNA increased with time upon HSC activation. 5-HT2A receptor antagonists (ketanserin and sarpogrelate) inhibited viability and wound healing in LX-2 cells and induced apoptosis. Expression of α-SMA and procollagen type I was also inhibited. In the in vivo study, lobular inflammation was reduced in the sarpogrelate-treated group, but there was only slight and statistically insignificant attenuation of periportal fibrosis. Expression of α-SMA, TGF-β and Smad 2/3 was also reduced in the treatment group. 5-HT2A receptor antagonists can reduce inflammation and the activation of HSCs in this cirrhotic model. © 2013 John Wiley & Sons A/S.

  10. Preliminary study of the uranium favorability of Malheur County, Oregon

    International Nuclear Information System (INIS)

    Erikson, E.H.

    1977-11-01

    A reconnaissance study of middle and upper Tertiary volcaniclastic sedimentary and silicic volcanic rocks in Malheur County, Oregon, indicates that, based upon the data available: (1) it is unlikely that sandstone-type uranium deposits exist in sedimentary rocks of north-central Malheur County; and (2) favorable uranium environments are more likely to exist in and adjacent to uraniferous silicic eruptive centers and plugs. Some rhyolites in the northern part of the county contain marginally anomalous uranium abundances (6 to 8 +- 2 ppM U 3 O 8 ), compared with similar rocks in southeastern Oregon. Available uranium from these rocks, as determined by nitric-acid leaching, approaches 50 to 75 percent of the total chemical U 3 O 8 present. One Pliocene rhyolite vitrophyre sample from Duck Butte in western Malheur County contains 9 +- 2 ppM U 3 O 8 . The uranium contents of these rhyolites approach those found in silicic plugs spatially related to uranium deposits in the Lakeview district, Oregon (Erikson and Curry, 1977). It is possible that undiscovered epithermal and (or) supergene uranium deposits may exist in favorable wall rocks subjacent to uraniferous silicic eruptive centers (Duck Butte), calderas (McDermitt caldera to the south and others identified in western Owyhee County, Idaho), and silicic plugs (as in the Lakeview district). With the exception of one small uranium anomaly found in unconsolidated sands in the Grassy Mountain Formation, the sedimentary rocks observed in the study area did not possess abnormal radioactivity or exhibit evidence of uranium mobility and enrichment. Carbonaceous trash is uncommon in these rocks. Gently dipping sandstone members of the Deer Butte Formation (upper Miocene) and local channel sands in the Grassy Mountain Formation (Pliocene) may have once been the most permeable rocks in the Tertiary section; but, there is no evidence to suggest that they were conduits for uranium-bearing solutions

  11. High nevus counts confer a favorable prognosis in melanoma patients.

    Science.gov (United States)

    Ribero, Simone; Davies, John R; Requena, Celia; Carrera, Cristina; Glass, Daniel; Rull, Ramon; Vidal-Sicart, Sergi; Vilalta, Antonio; Alos, Lucia; Soriano, Virtudes; Quaglino, Pietro; Traves, Victor; Newton-Bishop, Julia A; Nagore, Eduardo; Malvehy, Josep; Puig, Susana; Bataille, Veronique

    2015-10-01

    A high number of nevi is the most significant phenotypic risk factor for melanoma and is in part genetically determined. The number of nevi decreases from middle age onward but this senescence can be delayed in patients with melanoma. We investigated the effects of nevus number count on sentinel node status and melanoma survival in a large cohort of melanoma cases. Out of 2,184 melanoma cases, 684 (31.3%) had a high nevus count (>50). High nevus counts were associated with favorable prognostic factors such as lower Breslow thickness, less ulceration and lower mitotic rate, despite adjustment for age. Nevus count was not predictive of sentinel node status. The crude 5- and 10-year melanoma-specific survival rate was higher in melanomas cases with a high nevus count compared to those with a low nevus count (91.2 vs. 86.4% and 87.2 vs. 79%, respectively). The difference in survival remained significant after adjusting for all known melanoma prognostic factors (hazard ratio [HR] = 0.43, confidence interval [CI] = 0.21-0.89). The favorable prognostic value of a high nevus count was also seen within the positive sentinel node subgroup of patients (HR = 0.22, CI = 0.08-0.60). High nevus count is associated with a better melanoma survival, even in the subgroup of patients with positive sentinel lymph node. This suggests a different biological behavior of melanoma tumors in patients with an excess of nevi. © 2015 The Authors. Published by Wiley Periodicals, Inc. on behalf of UICC.

  12. Antagonist potential of Trichoderma indigenous isolates for ...

    African Journals Online (AJOL)

    STORAGESEVER

    2009-10-19

    Oct 19, 2009 ... Full Length Research Paper. Antagonist potential of Trichoderma indigenous isolates for biological control of Phytophthora palmivora the causative agent of black pod disease on cocoa (Theobroma cacao L.) in Côte d'Ivoire. J. Mpika1,4*, I. B. Kébé1, A. E. Issali2, F.K. N'Guessan1, S. Druzhinina3, ...

  13. Medicinal Chemistry of Competitive Kainate Receptor Antagonists

    Science.gov (United States)

    2010-01-01

    Kainic acid (KA) receptors belong to the group of ionotropic glutamate receptors and are expressed throughout in the central nervous system (CNS). The KA receptors have been shown to be involved in neurophysiological functions such as mossy fiber long-term potentiation (LTP) and synaptic plasticity and are thus potential therapeutic targets in CNS diseases such as schizophrenia, major depression, neuropathic pain and epilepsy. Extensive effort has been made to develop subtype-selective KA receptor antagonists in order to elucidate the physiological function of each of the five subunits known (GluK1−5). However, to date only selective antagonists for the GluK1 subunit have been discovered, which underlines the strong need for continued research in this area. The present review describes the structure−activity relationship and pharmacological profile for 10 chemically distinct classes of KA receptor antagonists comprising, in all, 45 compounds. To the medicinal chemist this information will serve as reference guidance as well as an inspiration for future effort in this field. PMID:22778857

  14. The sexually antagonistic genes of Drosophila melanogaster.

    Directory of Open Access Journals (Sweden)

    Paolo Innocenti

    2010-03-01

    Full Text Available When selective pressures differ between males and females, the genes experiencing these conflicting evolutionary forces are said to be sexually antagonistic. Although the phenotypic effect of these genes has been documented in both wild and laboratory populations, their identity, number, and location remains unknown. Here, by combining data on sex-specific fitness and genome-wide transcript abundance in a quantitative genetic framework, we identified a group of candidate genes experiencing sexually antagonistic selection in the adult, which correspond to 8% of Drosophila melanogaster genes. As predicted, the X chromosome is enriched for these genes, but surprisingly they represent only a small proportion of the total number of sex-biased transcripts, indicating that the latter is a poor predictor of sexual antagonism. Furthermore, the majority of genes whose expression profiles showed a significant relationship with either male or female adult fitness are also sexually antagonistic. These results provide a first insight into the genetic basis of intralocus sexual conflict and indicate that genetic variation for fitness is dominated and maintained by sexual antagonism, potentially neutralizing any indirect genetic benefits of sexual selection.

  15. Pharmacological analysis of calcium antagonist receptors

    International Nuclear Information System (INIS)

    Reynolds, I.J.

    1987-01-01

    This work focuses on two aspects of the action of calcium antagonist drugs, namely, the interaction of drugs with receptors for verapamil-like calcium antagonists, and the interactions of drugs with voltage-sensitive calcium fluxes in rat brain synaptosomes. From binding studies I have found that the ligand of choice for labeling the verapamil receptor is (-)[ 3 H]desmethoxy-verapamil. This drug labels potently, reversibly and stereoselectively two receptors in membranes prepared from rat brain and rabbit skeletal muscle tissues. In equilibrium studies dihydropyridine calcium antagonists interact in a non-competitive fashion, while many non-DHPs are apparently competitive. In-depth kinetic studies in skeletal muscle membranes indicate that the two receptors are linked in a negative heterotropic fashion, and that low-affinity binding of (-) [ 3 H]desmethoxy-verapamil may be to the diltiazem receptor. However, these studies were not able to distinguish between the hypothesis that diltiazem binds to spatially separate, allosterically coupled receptors, and the hypothesis that diltiazem binds to a subsite of the verapamil receptor

  16. NMDA Receptor Antagonists for Treatment of Depression

    Directory of Open Access Journals (Sweden)

    Zeynep Ates-Alagoz

    2013-04-01

    Full Text Available Depression is a psychiatric disorder that affects millions of people worldwide. Individuals battling this disorder commonly experience high rates of relapse, persistent residual symptoms, functional impairment, and diminished well-being. Medications have important utility in stabilizing moods and daily functions of many individuals. However, only one third of patients had considerable improvement with a standard antidepressant after 2 months and all patients had to deal with numerous side effects. The N-methyl-d-aspartate (NMDA receptor family has received special attention because of its critical role in psychiatric disorders. Direct targeting of the NMDA receptor could result in more rapid antidepressant effects. Antidepressant-like effects of NMDA receptor antagonists have been demonstrated in different animal models. MK-801 (a use-dependent channel blocker, and CGP 37849 (an NMDA receptor antagonist have shown antidepressant properties in preclinical studies, either alone or combined with traditional antidepressants. A recent development is use of ketamine clinically for refractory depression. The purpose of this review is to examine and analyze current literature on the role of NMDA receptor antagonists for treatment of depression and whether this is a feasible route in drug discovery.

  17. AVN-322 is a Safe Orally Bio-Available Potent and Highly Selective Antagonist of 5-HT6R with Demonstrated Ability to Improve Impaired Memory in Animal Models.

    Science.gov (United States)

    Ivachtchenko, Alexandre V; Ivanenkov, Yan A; Veselov, Mark S; Okun, I M

    2017-01-01

    In recent years, 5-hydroxytryptamine subtype 6 receptor (5-HT6 receptor, 5- HT6R) has emerged as a promising therapeutic target for the treatment of neuropathological disorders, including Alzheimer's disease (AD) and schizophrenia. 5-HT6 receptors were hypothesized to be implicated in the processes of learning, memory, and cognition with 5-HT6R antagonists being effective in animal models of cognition and memory impairment. Several selective 5-HT6R ligands are currently undergoing clinical trials for treatment of AD. We describe results of preclinical development of a novel and highly selective and potent 5- HT6R antagonist, AVN-322, as a clinical candidate for the treatment of AD to improve concurrent debilitation of memory and cognition in the AD patients, and schizophrenia as a substance with antipsychotic effect. In the manuscript, we present its in vitro and vivo efficacy, ADME, pharmacokinetics in animals and in humans, and toxicity. While having high binding affinity in medium picomolar range, the lead compound demonstrates substantially better selectivity index then the reference drug candidates currently being tested in clinical studies. AVN-322 showed high oral bioavailability and favorable blood-brain barrier (BBB) penetration. In vivo testing revealed its clear cognition enhancing effect. AVN-322 significantly restored both scopolamine- and MK-801-induced cognitive dysfunction and demonstrated antipsychotic potential. Taking into account its good safety profile and favorable pharmacokinetics, AVN-322 can be reasonably considered as a novel drug candidate for the treatment of neurological disorders such as AD and/or schizophrenia. Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.org.

  18. Pig as a Favorable Animal for Taenia Saginata Asiatica Infection

    Directory of Open Access Journals (Sweden)

    Ping-Chin Fan

    2006-01-01

    Full Text Available The epidemiology of Taenia saginata in some parts of Asia is confusing, in that beef does not appear to be the source of infection. In some areas, beef is either not available or not eaten raw, whereas pork at times is eaten uncooked. In light of this situation, we have exposed pigs and other animals to infection with strains of T. saginata to establish their ability to serve as intermediate hosts. Eggs of Taiwan Taenia, Korea Taenia, Indonesia Taenia, Thailand Taenia, Philippines Taenia, Ethiopia Taenia, and Madagascar Taenia were fed to 83 pigs of three strains: 43 Small-Ear Miniature (SEM, 34 Landrace Small-Ear Miniature (L-SEM, and 6 Duroc-Yorkshire-Landrace (DYL. We also fed the eggs to 10 Holstein calves, 17 Sannean goats, and 4 monkeys (Macaca cyclopis. We succeeded in infecting SEM (infection rate 88%, cysticercus recovery rate 19.1%, L-SEM (83%, 1.1%, and DYL (100%, 0.3% pigs with Taiwan Taenia; SEM (100%, 1.7%, L-SEM (100%, 5.6%, and DYL (100%, 0.06% pigs with Korea Taenia; SEM (100%, 22% and L-SEM (100%, 1.6% pigs with Indonesia Taenia; SEM (75%, 0.06% pigs with Thailand Taenia SEM (100%, 11% pigs with Philippines Taenia; SEM (80%, 0.005% pigs with Ethiopia Taenia; SEM (100%, 0.2% pigs with Madagascar Taenia. Holstein calves became infected with Taenia from Taiwan (100%, 1.1%, Korea (100%, 0.03%, Thailand (100%, 0.2%, and the Philippines (100%, 6%; however, the cysticerci of Taenia from Korea, Thailand, and the Philippines were degenerated and/or calcified. Sannean goats became infected with Taenia from Taiwan (33%, 0.01% and Korea (50%, 0.02%, while monkeys became infected with Taenia from Taiwan (50%, 0.01%. However, the cysticerci were degenerated and/or calcified. Therefore, these strains of pig seem to be favorable animal models for experimental studies of T. saginata-like tapeworms, with the SEM pig the most favorable.

  19. Pig as a favorable animal for Taenia saginata asiatica infection.

    Science.gov (United States)

    Fan, Ping-Chin; Chung, Win-Cheng; Lin, Chung-Yung; Wu, Chin-Cheng

    2006-01-01

    The epidemiology of Taenia saginata in some parts of Asia is confusing, in that beef does not appear to be the source of infection. In some areas, beef is either not available or not eaten raw, whereas pork at times is eaten uncooked. In light of this situation, we have exposed pigs and other animals to infection with strains of T. saginata to establish their ability to serve as intermediate hosts. Eggs of Taiwan Taenia, Korea Taenia, Indonesia Taenia, Thailand Taenia, Philippines Taenia, Ethiopia Taenia, and Madagascar Taenia were fed to 83 pigs of three strains: 43 Small-Ear Miniature (SEM), 34 Landrace Small-Ear Miniature (L-SEM), and 6 Duroc-Yorkshire-Landrace (DYL). We also fed the eggs to 10 Holstein calves, 17 Sannean goats, and 4 monkeys (Macaca cyclopis). We succeeded in infecting SEM (infection rate 88%, cysticercus recovery rate 19.1%), L-SEM (83%, 1.1%), and DYL (100%, 0.3%) pigs with Taiwan Taenia; SEM (100%, 1.7%), L-SEM (100%, 5.6%), and DYL (100%, 0.06%) pigs with Korea Taenia; SEM (100%, 22%) and L-SEM (100%, 1.6%) pigs with Indonesia Taenia; SEM (75%, 0.06%) pigs with Thailand Taenia SEM (100%, 11%) pigs with Philippines Taenia; SEM (80%, 0.005%) pigs with Ethiopia Taenia; SEM (100%, 0.2%) pigs with Madagascar Taenia. Holstein calves became infected with Taenia from Taiwan (100%, 1.1%), Korea (100%, 0.03%), Thailand (100%, 0.2%), and the Philippines (100%, 6%); however, the cysticerci of Taenia from Korea, Thailand, and the Philippines were degenerated and/or calcified. Sannean goats became infected with Taenia from Taiwan (33%, 0.01%) and Korea (50%, 0.02%), while monkeys became infected with Taenia from Taiwan (50%, 0.01%). However, the cysticerci were degenerated and/ or calcified. Therefore, these strains of pig seem to be favorable animal models for experimental studies of T. saginata-like tapeworms, with the SEM pig the most favorable.

  20. Diltiazem, an antagonist of calcium channels, reduces norepinephrine in the rat myocardium.

    Science.gov (United States)

    Obata, Toshio

    2006-10-01

    The present study examined the effect of diltiazem, a calcium channel antagonist, on potassium (K(+)) depolarization-induced norepinephrine (NE) release in rat myocardium using a flexibly mounted microdialysis technique. When high concentration of KCl (70 mM) was directly infused in rat heart through a microdialysis probe, the level of NE gradually increased in a time dependent manner. However, when a high concentration of KCl (70 mM) was administered to diltiazem-pretreated animals, it failed to increase the KCl-induced dialysate NE. These results suggest that calcium (Ca(2+)) may play a key role in K(+) depolarization-induced NE release in the myocardium.

  1. Development of potent antagonists for formyl peptide receptor 1 based on Boc-Phe-D-Leu-Phe-D-Leu-Phe-OH.

    Science.gov (United States)

    Hayashi, Ryo; Kitajima, Toshiki; Mizuguchi, Hikaru; Fujimoto, Miki; Yamaguchi, Aya; Koga, Shuichiro; Koga, Yuya; Osada, Satoshi; Kodama, Hiroaki

    2014-08-01

    While stimulation of formyl peptide receptors (FPRs) on the surface of human neutrophils induces several immune responses, under conditions of continuous activation of the receptor by agonists such as formyl-Met-Leu-Phe-OH (fMLP), neutrophil-dependent tissue damage ensues. Thus, FPR antagonists could be anticipated as drugs for FPR-related disease. In this study, Boc-Phe-D-Leu-Phe-D-Leu-Phe-OH (Boc-FlFlF), one of several FPR subtype selective antagonists, was chosen and the positions at the Phe residues were optimized. We found that substitution with unnatural amino acids resulted in an improvement of two orders of magnitude. The most potent antagonist indicated FPR subtype selectivity at 1 μM. In addition to finding a potent antagonist, the structure-activity trends observed in this study should be valuable in designing a new type of FPR subtype selective antagonist. Copyright © 2014 Elsevier Ltd. All rights reserved.

  2. Prevention of Stimulant Induced Euphoria with an Opioid Receptor Antagonist

    Science.gov (United States)

    2017-02-28

    Aviat Space Environ Med, 2005. 76(1): p. 39- 45. 8. Westcott, K.J., Modafinil, sleep deprivation , and cognitive function in military and medical settings...51. 6. Caldwell, J.A., et al., Modafinil’s effects on simulator performance and mood in pilots during 37 h without sleep . Aviat Space Environ Med, 2004...75(9): p. 777-84. 7. McLellan, T.M., et al., Caffeine maintains vigilance and marksmanship in simulated urban operations with sleep deprivation

  3. [Incidence of factors favoring recurrent foot ulcers in diabetic patients].

    Science.gov (United States)

    Diouri, A; Slaoui, Z; Chadli, A; El Ghomari, H; Kebbou, M; Marouan, F; Farouqi, A; Ababou, M R

    2002-12-01

    Patients with foot ulcers have a high risk of relapse and amputation. Several studies have reported that 28 to 51% of amputated diabetics will have a second amputation of the lower limb within five years of the first amputation. The purpose of this study was to assess the incidence of factors favoring relapse within two years. One hundred ten diabetic patients were treated for foot lesions in the Casablanca Ibn Rochd university hospital between 1997 and 2000. Ninety of these patients attended review consultations. There were 42 cases of relapse (46.6%). Male gender predominated in the relapse patients with a sex ratio of 3.2. Mean age at relapse was 55 years; 71.5% of the patients had type 2 diabetes. Lesions observed were neuropathic ulcer (n=23), arterial ulcer (n=6), infected wounds (n=13). Revealing factors were burns and wounds. The main risk factors were neuropathy (n=23, 52%), neuroarteriopathy (n=12, 31%), peur arteriopathy (n=6, 12%). Patients who relapsed (n=42) were significantly different from patients who did not relapse (n=48) for gender, presence or absence of neuropathy, and presence or absence of arteriopathy. Secondary preventive measures against these risk factors, medical care, and specialized follow-up were satisfactory in these patients. our findings illustrate the importance of specialized management of diabetic patients with foot lesions. Adequate care of the lesions and preventive measures against risk factors are needed.

  4. Immunosuppression with cyclophosphamide favors reinfection with recombinant Toxoplasma gondii strains

    Directory of Open Access Journals (Sweden)

    Silva L.A.

    2012-08-01

    Full Text Available The aim of this study was to verify the effect of immunosuppression by cyclophosphamide (Cy on susceptibility of BALB/c mice subjected to challenge with recombinant strains of Toxoplasma gondii. Animals were prime infected with the D8 (recombinant I/III or the ME49 (type II non-virulent strains, weekly immunosuppressed with Cy and challenged with the CH3 or EGS virulent strains (I/III. Parasites recovered from surviving mice were submitted to PCR-RFLP analysis to confirm co-infection. Prime-infection with the D8 strain conferred more protection against challenge with the CH3 and EGS strains when compared with ME49 prime infection. Cy treatment caused significant leukopenia in the infected mice, what probably favors reinfection after challenge. Reinfection was associated with increased levels of IgA. Otherwise, Cy-treated mice presented significantly lower IgA levels after challenge, suggesting involvement of this immunoglobulin on protection against reinfection. In conclusion, BALB/c mice susceptibility to reinfection by T. gondii is related to genetic differences among the strains used for primary and challenge infections. Alteration of the host’s immune integrity by Cy probably compromises the protection previously established by primary infection.

  5. Paleozoic unconformities favorable for uranium concentration in northern Appalachian basin

    International Nuclear Information System (INIS)

    Dennison, J.M.

    1986-01-01

    Unconformities can redistribute uranium from protore rock as ground water moves through poorly consolidated strata beneath the erosion surface, or later moves along the unconformity. Groundwater could migrate farther than in present-day lithified Paleozoic strata in the Appalachian basin, now locally deformed by the Taconic and Allegheny orogenies. Several paleoaquifer systems could have developed uranium geochemical cells. Sandstone mineralogy, occurrences of fluvial strata, and reduzate facies are important factors. Other possibilities include silcrete developed during desert exposure, and uranium concentrated in paleokarst. Thirteen unconformities are evaluated to determine favorable areas for uranium concentration. Cambrian Potsdam sandstone (New York) contains arkoses and possible silcretes just above crystalline basement. Unconformities involving beveled sandstones and possible fluvial strata include Cambrian Hardyston sandstone (New Jersey), Cambrian Potsdam Sandstone (New York), Ordovician Oswego and Juniata formations (Pennsylvania and New York), Silurian Medina Group (New York), and Silurian Vernon, High Falls, and Longwood formations (New York and New Jersey). Devonian Catskill Formation is beveled by Pennsylvanian strata (New York and Pennsylvania). The pre-Pennsylvanian unconformity also bevels Lower Mississippian Pocono, Knapp, and Waverly strata (Pennsylvania, New York, and Ohio), truncates Upper Mississippian Mauch Chunk Formation (Pennsylvania), and forms paleokarst on Mississippian Loyalhanna Limestone (Pennsylvania) and Maxville Limestone (Ohio). Strata associated with these unconformities contain several reports of uranium. Unconformities unfavorable for uranium concentration occur beneath the Middle Ordovician (New York), Middle Devonian (Ohio and New York), and Upper Devonian (Ohio and New York); these involve marine strata overlying marine strata and probably much submarine erosion

  6. Musical FAVORS: Reintroducing music to adult cochlear implant users.

    Science.gov (United States)

    Plant, Geoff

    2015-09-01

    Music represents a considerable challenge for many adult users of cochlear implants (CIs). Around half of adult CI users report that they do not find music enjoyable, and, in some cases, despite enhanced speech perception skills, this leads to considerable frustration and disappointment for the CI user. This paper presents suggestions to improve the musical experiences of deafened adults with CIs. Interviews with a number of adult CI users revealed that there were a number of factors which could lead to enhanced music experiences. The acronym FAVORS (familiar music, auditory-visual access, open-mindedness, and simple arrangements) summarizes the factors that have been identified, which can help CI users in their early music listening experiences. Each of these factors is discussed in detail, along with suggestions for how they can be used in therapy sessions. The use of a group approach (music focus groups) is also discussed and an overview of the approach and exercises used is presented. The importance of live music experiences is also discussed.

  7. Heterolytic dissociative adsorption state of dihydrogen favored by interfacial defects

    Science.gov (United States)

    Song, Zhenjun; Hu, Hanshi; Xu, Hu; Li, Yong; Cheng, Peng; Zhao, Bin

    2018-03-01

    The atomic-scale insight into dihydrogen on MgO(001) surface deposited on molybdenum substrate with interfacial defects was investigated in detail by employing density functional methods Here we report novel dissociative adsorption behaviors of single hydrogen molecule on the usually inert oxide surfaces, with consideration of two types of dissociation schemes. The heterolytic dissociation state -Mg(H)-O(H)- of dihydrogen is impossible to obtain on neighboring O-Mg sites of perfect bulk MgO(001) terraces. Unusually, the hydrogen molecule can form heterolytic fragmentation states on metal supported MgO(001) films with very low activation barrier (0.398 eV), and the heterolytic dissociation state is much more favorable than homolytic dissociation state both energetically and kinetically in all cases. Electronic properties and bonding attribution of adsorbates and the oxide-metal hybrid structure are revealed by analyzing density of states, differential charge densities, orbital interaction and electron localization function. The characteristic changes to the property and activity of magnesia (001) can have potential application in catalytic reactions.

  8. Competition favors elk over beaver in a riparian willow ecosystem

    Science.gov (United States)

    Baker, B.W.; Peinetti, H.R.; Coughenour, M.C.; Johnson, T.L.

    2012-01-01

    Beaver (Castor spp.) conservation requires an understanding of their complex interactions with competing herbivores. Simulation modeling offers a controlled environment to examine long-term dynamics in ecosystems driven by uncontrollable variables. We used a new version of the SAVANNA ecosystem model to investigate beaver (C. Canadensis) and elk (Cervus elapses) competition for willow (Salix spp.). We initialized the model with field data from Rocky Mountain National Park, Colorado, USA, to simulate a 4-ha riparian ecosystem containing beaver, elk, and willow. We found beaver persisted indefinitely when elk density was or = 30 elk km_2. The loss of tall willow preceded rapid beaver declines, thus willow condition may predict beaver population trajectory in natural environments. Beaver were able to persist with slightly higher elk densities if beaver alternated their use of foraging sites in a rest-rotation pattern rather than maintained continuous use. Thus, we found asymmetrical competition for willow strongly favored elk over beaver in a simulated montane ecosystem. Finally, we discuss application of the SAVANNA model and mechanisms of competition relative to beaver persistence as metapopulations, ecological resistance and alternative state models, and ecosystem regulation.

  9. Implementation of a fluorescence-based screening assay identifies histamine H3 receptor antagonists clobenpropit and iodophenpropit as subunit-selective N-methyl-D-aspartate receptor antagonists

    DEFF Research Database (Denmark)

    Hansen, Kasper Bø; Mullasseril, Praseeda; Dawit, Sara

    2010-01-01

    N-Methyl-D-aspartate (NMDA) receptors are ligand-gated ion channels that mediate a slow, Ca(2+)-permeable component of excitatory synaptic transmission in the central nervous system and play a pivotal role in synaptic plasticity, neuronal development, and several neurological diseases. We describe...... a fluorescence-based assay that measures NMDA receptor-mediated changes in intracellular calcium in a BHK-21 cell line stably expressing NMDA receptor NR2D with NR1 under the control of a tetracycline-inducible promoter (Tet-On). The assay selectively identifies allosteric modulators by using supramaximal...... concentrations of glutamate and glycine to minimize detection of competitive antagonists. The assay is validated by successfully identifying known noncompetitive, but not competitive NMDA receptor antagonists among 1800 screened compounds from two small focused libraries, including the commercially available...

  10. Combination decongestion therapy in hospitalized heart failure: loop diuretics, mineralocorticoid receptor antagonists and vasopressin antagonists.

    Science.gov (United States)

    Vaduganathan, Muthiah; Mentz, Robert J; Greene, Stephen J; Senni, Michele; Sato, Naoki; Nodari, Savina; Butler, Javed; Gheorghiade, Mihai

    2015-01-01

    Congestion is the most common reason for admissions and readmissions for heart failure (HF). The vast majority of hospitalized HF patients appear to respond readily to loop diuretics, but available data suggest that a significant proportion are being discharged with persistent evidence of congestion. Although novel therapies targeting congestion should continue to be developed, currently available agents may be utilized more optimally to facilitate complete decongestion. The combination of loop diuretics, natriuretic doses of mineralocorticoid receptor antagonists and vasopressin antagonists represents a regimen of currently available therapies that affects early and persistent decongestion, while limiting the associated risks of electrolyte disturbances, hemodynamic fluctuations, renal dysfunction and mortality.

  11. Investigation of orexin-2 selective receptor antagonists: Structural modifications resulting in dual orexin receptor antagonists.

    Science.gov (United States)

    Skudlarek, Jason W; DiMarco, Christina N; Babaoglu, Kerim; Roecker, Anthony J; Bruno, Joseph G; Pausch, Mark A; O'Brien, Julie A; Cabalu, Tamara D; Stevens, Joanne; Brunner, Joseph; Tannenbaum, Pamela L; Wuelfing, W Peter; Garson, Susan L; Fox, Steven V; Savitz, Alan T; Harrell, Charles M; Gotter, Anthony L; Winrow, Christopher J; Renger, John J; Kuduk, Scott D; Coleman, Paul J

    2017-03-15

    In an ongoing effort to explore the use of orexin receptor antagonists for the treatment of insomnia, dual orexin receptor antagonists (DORAs) were structurally modified, resulting in compounds selective for the OX 2 R subtype and culminating in the discovery of 23, a highly potent, OX 2 R-selective molecule that exhibited a promising in vivo profile. Further structural modification led to an unexpected restoration of OX 1 R antagonism. Herein, these changes are discussed and a rationale for selectivity based on computational modeling is proposed. Copyright © 2017 Elsevier Ltd. All rights reserved.

  12. Regulation of the adrenoleukodystrophy-related gene (ABCD2): focus on oxysterols and LXR antagonists.

    Science.gov (United States)

    Trompier, Doriane; Gondcaille, Catherine; Lizard, Gérard; Savary, Stéphane

    2014-04-11

    The regulation of the ABCD2 gene is recognized as a possible therapeutic target for X-linked adrenoleukodystrophy, a rare neurodegenerative disease caused by mutations in the ABCD1 gene. Up-regulation of ABCD2 expression has indeed been demonstrated to compensate for ABCD1 deficiency, restoring peroxisomal β-oxidation of very-long-chain fatty acids. Besides the known inducers of the ABCD2 gene (phenylbutyrate and histone deacetylase inhibitors, fibrates, dehydroepiandrosterone, thyroid hormone and thyromimetics), this review will focus on LXR antagonists and 22S-hydroxycholesterol, recently described as inducers of ABCD2 expression. Several LXR antagonists have been identified and their possible indication for neurodegenerative disorders will be discussed. Copyright © 2014 Elsevier Inc. All rights reserved.

  13. Drm/Gremlin, a BMP antagonist, defines the interbud region during feather development.

    Science.gov (United States)

    Bardot, Boris; Lecoin, Laure; Fliniaux, Ingrid; Huillard, Emmanuelle; Marx, Maria; Viallet, Jean P

    2004-01-01

    The pattern of feather buds in a tract is thought to result from the relative ratios between activator and inhibitor signals through a lateral inhibition process. We analyse the role of Drm/Gremlin, a BMPs antagonist expressed during feather pattern formation, in the dermal precursor, the dense dermis, the interbud dermis and in the posterior dermal condensation. We have altered the activity of Drm in embryonic chick skin using retroviral vectors expressing drm/ gremlin and bmps. We show that expression of endogenous drm is under the control of a feedback loop induced by the BMP pathway, and that overexpression of drm results in fusion between adjacent feather buds. We propose that endogenous BMP proteins induce drm expression in the interbud dermis. In turn, the Drm/Gremlin protein limits the inhibitory effect of BMPs, allowing the adjacent row of feathers to form. Thus, the balance between BMPs and its antagonist Drm would regulate the size and spacing of the buds.

  14. Evidence that diclofenac and celecoxib are thyroid hormone receptor beta antagonists.

    Science.gov (United States)

    Zloh, Mire; Perez-Diaz, Noelia; Tang, Leslie; Patel, Pryank; Mackenzie, Louise S

    2016-02-01

    Long term use of NSAIDs is linked to side effects such as gastric bleeding and myocardial infarction. Use of in silico methods and pharmacology to investigate the potential for NSAIDs diclofenac, celecoxib and naproxen to bind to nuclear receptors. In silico screening predicted that both diclofenac and celecoxib has the potential to bind to a number of different nuclear receptors; docking analysis confirmed a theoretical ability for diclofenac and celecoxib but not naproxen to bind to TRβ. Results from TRβ luciferase reporter assays confirmed that both diclofenac and celecoxib display TRβ antagonistic properties; celecoxib, IC50 3.6 × 10(-6)M, and diclofenac IC50 5.3 × 10(-6)M, comparable to the TRβ antagonist MLS (IC50 3.1 × 10(-6)M). In contrast naproxen, a cardio-sparing NSAID, lacked TRβ antagonist effects. In order to determine the effects of NSAIDs in whole organ in vitro, we used isometric wire myography to measure the changes to Triiodothyronine (T3) induced vasodilation of rat mesenteric arteries. Incubation of arteries in the presence of the TRβ antagonist MLS000389544 (10(-5)M), as well as diclofenac (10(-5)M) and celecoxib (10(-5)M) but not naproxen significantly inhibited T3 induced vasodilation compared to controls. These results highlight the benefits of computational chemistry methods used to retrospectively analyse well known drugs for side effects. Using in silico and in vitro methods we have shown that both celecoxib and diclofenac but not naproxen exhibit off-target TRβ antagonist behaviour, which may be linked to their detrimental side effects. Copyright © 2016 Elsevier Inc. All rights reserved.

  15. A presumed antagonistic LPS identifies distinct functional organization of TLR4 in mouse microglia.

    Science.gov (United States)

    Döring, Christin; Regen, Tommy; Gertig, Ulla; van Rossum, Denise; Winkler, Anne; Saiepour, Nasrin; Brück, Wolfgang; Hanisch, Uwe-Karsten; Janova, Hana

    2017-07-01

    Microglia as principle innate immune cells of the central nervous system (CNS) are the first line of defense against invading pathogens. They are capable of sensing infections through diverse receptors, such as Toll-like receptor 4 (TLR4). This receptor is best known for its ability to recognize bacterial lipopolysaccharide (LPS), a causative agent of gram-negative sepsis and septic shock. A putative, naturally occurring antagonist of TLR4 derives from the photosynthetic bacterium Rhodobacter sphaeroides. However, the antagonistic potential of R. sphaeroides LPS (Rs-LPS) is no universal feature, since several studies suggested agonistic rather than antagonistic actions of this molecule depending on the investigated mammalian species. Here we show the agonistic versus antagonistic potential of Rs-LPS in primary mouse microglia. We demonstrate that Rs-LPS efficiently induces the release of cytokines and chemokines, which depends on TLR4, MyD88, and TRIF, but not CD14. Furthermore, Rs-LPS is able to regulate the phagocytic capacity of microglia as agonist, while it antagonizes Re-LPS-induced MHC I expression. Finally, to our knowledge, we are the first to provide in vivo evidence for an agonistic potential of Rs-LPS, as it efficiently triggers the recruitment of peripheral immune cells to the endotoxin-challenged CNS. Together, our results argue for a versatile and complex organization of the microglial TLR4 system, which specifically translates exogenous signals into cellular functions. Importantly, as demonstrated here for microglia, the antagonistic potential of Rs-LPS needs to be considered with caution, as reactions to Rs-LPS not only differ by cell type, but even by function within one cell type. © 2017 Wiley Periodicals, Inc.

  16. Discovery of Potential Orthosteric and Allosteric Antagonists of P2Y1R from Chinese Herbs by Molecular Simulation Methods

    Science.gov (United States)

    Lu, Fang; Jiang, Lu-di; Qiao, Lian-sheng; Xiang, Yu-hong

    2016-01-01

    P2Y1 receptor (P2Y1R), which belongs to G protein-coupled receptors (GPCRs), is an important target in ADP-induced platelet aggregation. The crystal structure of P2Y1R has been solved recently, which revealed orthosteric and allosteric ligand-binding sites with the details of ligand-protein binding modes. And it suggests that P2Y1R antagonists, which recognize two distinct sites, could potentially provide an efficacious and safe antithrombotic profile. In present paper, 2D similarity search, pharmacophore based screening, and molecular docking were used to explore the potential natural P2Y1R antagonists. 2D similarity search was used to classify orthosteric and allosteric antagonists of P2Y1R. Based on the result, pharmacophore models were constructed and validated by the test set. Optimal models were selected to discover potential P2Y1R antagonists of orthosteric and allosteric sites from Traditional Chinese Medicine (TCM). And the hits were filtered by Lipinski's rule. Then molecular docking was used to refine the results of pharmacophore based screening and analyze the binding mode of the hits and P2Y1R. Finally, two orthosteric and one allosteric potential compounds were obtained, which might be used in future P2Y1R antagonists design. This work provides a reliable guide for discovering natural P2Y1R antagonists acting on two distinct sites from TCM. PMID:27635149

  17. 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

  18. Reduction of periodontal pathogens adhesion by antagonistic strains.

    Science.gov (United States)

    Van Hoogmoed, C G; Geertsema-Doornbusch, G I; Teughels, W; Quirynen, M; Busscher, H J; Van der Mei, H C

    2008-02-01

    Periodontitis results from a shift in the subgingival microflora into a more pathogenic direction with Porphyromonas gingivalis, Prevotella intermedia, and Actinobacillus actinomycetemcomitans considered as periodontopathogens. In many cases, treatment procures only a temporary shift towards a less pathogenic microflora. An alternative treatment could be the deliberate colonization of pockets with antagonistic microorganisms to control the adhesion of periodontopathogens. The aim of this study was to identify bacterial strains that reduce adhesion of periodontopathogens to surfaces. Streptococcus sanguinis, Streptococcus crista, Streptococcus salivarius, Streptococcus mitis, Actinomyces naeslundii, and Haemophilus parainfluenzae were evaluated as potential antagonists against P. gingivalis ATCC 33277, P. intermedia ATCC 49046, and A. actinomycetemcomitans ATCC 43718 as periodontopathogens. Adhesion of periodontopathogens to the bottom plate of a parallel plate flow chamber was studied in the absence (control) and the presence of pre-adhering antagonistic strains up to a surface coverage of 5%. The largest reduction caused by antagonistic strains was observed for P. gingivalis. All antagonistic strains except S. crista ATCC 49999 inhibited the adhesion of P. gingivalis by at least 1.6 cells per adhering antagonist, with the largest significant reduction observed for A. naeslundii ATCC 51655 (3.8 cells per adhering antagonist). Adhering antagonists had a minimal effect on the adhesion of A. actinomycetemcomitans ATCC 43718. Intermediate but significant reductions were perceived for P. intermedia, most notably caused by S. mitis BMS. The adhesion of P. gingivalis was inhibited best by antagonistic strains, while S. mitis BMS appeared to be the most successful antagonist.

  19. Examination of chlorpromazine and other amphipathic drugs on the activity of lipopolysaccharide antagonists, E5564 and E5531.

    Science.gov (United States)

    Yang, H; Daun, J M; Rose, J R; Christ, W J; Gusovsky, F; Chow, J C

    2000-01-01

    The synthetic antagonists of lipopolysaccharide (LPS), E5531 and E5564, are analogs of the lipid A portion of LPS that not only lack agonistic activity but also inhibit the biological effects of LPS both in vitro and in vivo. The effects of LPS and these synthetic antagonists have been localized to the recently described Toll-like receptor 4 (TLR4). A recent report indicated that the naturally occurring LPS antagonist Rhodobacter sphaeroides LPS loses its antagonist properties and gains pro-inflammatory qualities in the presence of chlorpromazine and other amphipathic drugs. To determine whether these reported actions occur with our chemically defined LPS antagonists, we examined the effects of chlorpromazine, fluphenazine, trifluoperazine, and lidocaine on the antagonism elicited by RsLPS and E5531 in U373 cells, which produce IL-6 in response to LPS. We also tested the effects of these amphipathic molecules on the LPS-neutralizing activity of RsLPS and E5564 on LPS-induced TNF-alpha release in human whole blood. The results indicate that neither chlorpromazine, fluphenazine, trifluoperazine nor lidocaine alter the activity of E5531 or E5564 in an in vitro cell system or human whole blood. Furthermore, chlorpromazine did not affect the antagonistic activity of RsLPS or E5564 on IL-6 generation by peripheral blood mononuclear cells. Thus, based on these data, our purified synthetic LPS-antagonists do not appear to lose their antagonistic properties and/or become agonists in the presence of amphipathic agents or drugs.

  20. What favors the occurrence of subduction mega-earthquakes?

    Science.gov (United States)

    Brizzi, Silvia; Funiciello, Francesca; Corbi, Fabio; Sandri, Laura; van Zelst, Iris; Heuret, Arnauld; Piromallo, Claudia; van Dinther, Ylona

    2017-04-01

    Most of mega-earthquakes (MEqs; Mw > 8.5) occur at shallow depths along the subduction thrust fault (STF). The contribution of each subduction zone to the globally released seismic moment is not homogenous, as well as the maximum recorded magnitude MMax. Highlighting the ingredients likely responsible for MEqs nucleation has great implications for hazard assessment. In this work, we investigate the conditions favoring the occurrence of MEqs with a multi-disciplinary approach based on: i) multivariate statistics, ii) analogue- and iii) numerical modelling. Previous works have investigated the potential dependence between STF seismicity and various subduction zone parameters using simple regression models. Correlations are generally weak due to the limited instrumental seismic record and multi-parameter influence, which make the forecasting of the potential MMax rather difficult. To unravel the multi-parameter influence, we perform a multivariate statistical study (i.e., Pattern Recognition, PR) of the global database on convergent margins (Heuret et al., 2011), which includes seismological, geometrical, kinematic and physical parameters of 62 subduction segments. PR is based on the classification of objects (i.e., subduction segments) belonging to different classes through the identification of possible repetitive patterns. Tests have been performed using different MMax datasets and combination of inputs to indirectly test the stability of the identified patterns. Results show that the trench-parallel width of the subducting slab (Wtrench) and the sediment thickness at the trench (Tsed) are the most recurring parameters for MEqs occurrence. These features are mostly consistent, independently of the MMax dataset and combination of inputs used for the analysis. MEqs thus seem to be promoted for high Wtrench and Tsed, as their combination may potentially favor extreme (i.e., in the order of thousands of km) trench-parallel rupture propagation. To tackle the

  1. Cyclosporin H, Boc-MLF and Boc-FLFLF are antagonists that preferentially inhibit activity triggered through the formyl peptide receptor.

    Science.gov (United States)

    Stenfeldt, Anna-Lena; Karlsson, Jennie; Wennerås, Christine; Bylund, Johan; Fu, Huamei; Dahlgren, Claes

    2007-12-01

    In order to properly interpret receptor inhibition experiments, the precise receptor specificities of the employed antagonists are of crucial importance. Lately, a great number of agonists for various formyl peptide receptors have been identified using a selection of antagonists. However, some confusion exists as to the precise receptor specificities of many of these antagonists. We have investigated the effects of formyl peptide receptor family antagonists on the neutrophil response induced by agonists for the formyl peptide receptor (FPR) and the formyl peptide receptor like 1 (FPRL1). To determine FPR- and FPRL1-specific interactions, these antagonists should not be used at used at concentrations above 10 microM. Signaling through FPR was inhibited by low concentrations of the antagonists cyclosporin H, Boc-MLF (also termed Boc-1), and Boc-FLFLFL (also termed Boc-2), while higher concentrations also partly inhibited the signaling through FPRL1. The antagonist WRWWWW (WRW(4)) specifically inhibited the signaling through FPRL1 at low concentrations but at high concentrations also partly the signaling through FPR. Based on the difference in potency of cyclosporin H and the two Boc-peptides, we suggest using cyclosporin H as a specific inhibitor for FPR. To specifically inhibit the FPRL1 response the antagonist WRW(4) should be used.

  2. Preliminary study of uranium favorability of the Boulder batholith, Montana

    Energy Technology Data Exchange (ETDEWEB)

    Castor, S.B.; Robins, J.W.

    1978-01-01

    The Boulder batholith of southwestern Montana is a composite Late Cretaceous intrusive mass, mostly composed of quartz monzonite and granodiorite. This study was not restricted to the plutonic rocks; it also includes younger rocks that overlie the batholith, and older rocks that it intrudes. The Boulder batholith area has good overall potential for economic uranium deposits, because its geology is similar to that of areas that contain economic deposits elsewhere in the world, and because at least 35 uranium occurrences of several different types are present. Potential is greatest for the occurrence of small uranium deposits in chalcedony veins and base-metal sulfide veins. Three areas may be favorable for large, low-grade deposits consisting of a number of closely spaced chalcedony veins and enriched wall rock; the Mooney claims, the Boulder area, and the Clancy area. In addition, there is a good possibility of by-product uranium production from phosphatic black shales in the project area. The potential for uranium deposits in breccia masses that cut prebatholith rocks, in manganese-quartz veins near Butte, and in a shear zone that cuts Tertiary rhyolite near Helena cannot be determined on the basis of available information. Low-grade, disseminated, primary uranium concentrations similar to porphyry deposits proposed by Armstrong (1974) may exist in the Boulder batholith, but the primary uranium content of most batholith rocks is low. The geologic environment adjacent to the Boulder batholith is similar in places to that at the Midnite mine in Washington. Some igneous rocks in the project area contain more than 10 ppM U/sub 3/O/sub 8/, and some metasedimentary rocks near the batholith contain reductants such as sulfides and carbonaceous material.

  3. Cordilleran metamorphic core complexes and their uranium favorability. Final report

    International Nuclear Information System (INIS)

    Coney, P.J.; Reynolds, S.J.

    1980-11-01

    The objective of this report is to provide a descriptive body of knowledge on Cordilleran metamorphic core complexes including their lithologic and structural characteristics, their distribution within the Cordillera, and their evolutionary history and tectonic setting. The occurrence of uranium in the context of possibility for uranium concentration is also examined. Chapter 1 is an overview of Cordilleran metamorphic core complexes which describes their physical characteristics, tectonic setting and geologic history. This overview is accompanied by a tectonic map. Chapter 2 is a discussion of the mantled gneiss dome concept. The purpose of including this work is to provide a basic history of this concept and to describe the characteristics and distribution of gneiss domes throughout the world to enable one to compare and contrast them with the metamorphic core complexes as discussed in this report. Some gneiss domes are known producers of uranium (as are also some core complexes). Chapter 3 is an examination of the effects of the core complex process on adjacent sedimentary and volcanic cover terranes. Also included is a discussion of the kinematic significance of these cover terranes as they are related to process within the cores of the complexes. Some of the cover terranes have uranium prospects in them. Chapter 4 is a detailed discussion of uranium in Cordilleran metamorphic core complexes and includes the conceptual basis for the various types of occurrences and the processes that might favor concentration of uranium. The report is supported by a 5-part Appendix. The majority of the core complexes discussed in this report either do not appear or are not recognizable on existing published geologic maps

  4. Preliminary study of uranium favorability of the Boulder batholith, Montana

    International Nuclear Information System (INIS)

    Castor, S.B.; Robins, J.W.

    1978-01-01

    The Boulder batholith of southwestern Montana is a composite Late Cretaceous intrusive mass, mostly composed of quartz monzonite and granodiorite. This study was not restricted to the plutonic rocks; it also includes younger rocks that overlie the batholith, and older rocks that it intrudes. The Boulder batholith area has good overall potential for economic uranium deposits, because its geology is similar to that of areas that contain economic deposits elsewhere in the world, and because at least 35 uranium occurrences of several different types are present. Potential is greatest for the occurrence of small uranium deposits in chalcedony veins and base-metal sulfide veins. Three areas may be favorable for large, low-grade deposits consisting of a number of closely spaced chalcedony veins and enriched wall rock; the Mooney claims, the Boulder area, and the Clancy area. In addition, there is a good possibility of by-product uranium production from phosphatic black shales in the project area. The potential for uranium deposits in breccia masses that cut prebatholith rocks, in manganese-quartz veins near Butte, and in a shear zone that cuts Tertiary rhyolite near Helena cannot be determined on the basis of available information. Low-grade, disseminated, primary uranium concentrations similar to porphyry deposits proposed by Armstrong (1974) may exist in the Boulder batholith, but the primary uranium content of most batholith rocks is low. The geologic environment adjacent to the Boulder batholith is similar in places to that at the Midnite mine in Washington. Some igneous rocks in the project area contain more than 10 ppM U 3 O 8 , and some metasedimentary rocks near the batholith contain reductants such as sulfides and carbonaceous material

  5. Survey of the Favorable Conditions for Magnetosonic Wave Excitation

    Science.gov (United States)

    Kim, Kyung-Chan; Shprits, Yuri

    2018-01-01

    The ratio of the proton ring velocity (VR) to the local Alfven speed (VA), in addition to proton ring distributions, plays a key factor in the excitation of magnetosonic waves at frequencies between the proton cyclotron frequency fcp and the lower hybrid resonance frequency fLHR in the Earth's magnetosphere. Here we investigate whether there is a statistically significant relationship between occurrences of proton rings and magnetosonic waves both outside and inside the plasmapause using particle and wave data from Van Allen Probe-A during the time period of October 2012 to December 2015. We also perform a statistical survey of the ratio of the ring energy (ER, corresponding to VR) to the Alfven energy (EA, corresponding to VA) to determine the favorable conditions under which magnetosonic waves in each of two frequency bands (fcp 0.5 fLHR and 0.5 fLHR LHR) can be excited. The results show that the magnetosonic waves in both frequency bands occur around the postnoon (12-18 magnetic local time, MLT) sector outside the plasmapause when ER is comparable to or lower than EA, and those in lower-frequency bands (fcp 0.5 fLHR) occur around the postnoon sector inside the plasmapause when ER/EA > 9. However, there is one discrepancy between occurrences of proton rings and magnetosonic waves in low-frequency bands around the prenoon sector (6-12 MLT) outside the plasmapause, which suggests either that the waves may have propagated during active time from the postnoon sector after being excited during quiet time, or they may have locally excited in the prenoon sector during active time.

  6. Thyroid Hormone Receptor Antagonists: From Environmental Pollution to Novel Small Molecules.

    Science.gov (United States)

    Mackenzie, Louise S

    2018-01-01

    Thyroid hormone receptors (TRs) are nuclear receptors which control transcription, and thereby have effects in all cells within the body. TRs are an important regulator in many basic physiological processes including development, growth, metabolism, and cardiac function. The hyperthyroid condition results from an over production of thyroid hormones resulting in a continual stimulation of thyroid receptors which is detrimental for the patient. Therapies for hyperthyroidism are available, but there is a need for new small molecules that act as TR antagonists to treat hyperthyroidism. Many compounds exhibit TR antagonism and are considered detrimental to health. Some drugs in the clinic (most importantly, amiodarone) and environmental pollution exhibit TR antagonist properties and thus have the potential to induce hypothyroidism in some people. This chapter provides an overview of novel small molecules that have been specifically designed or screened for their TR antagonist activity as novel treatments for hyperthyroidism. While novel compounds have been identified, to date none have been developed sufficiently to enter clinical trials. Furthermore, a discussion on other sources of TR antagonists is discussed in terms of side effects of current drugs in the clinic as well as environmental pollution. © 2018 Elsevier Inc. All rights reserved.

  7. Adenosine A2A receptor antagonists and Parkinson's disease: state of the art and future directions.

    Science.gov (United States)

    Simola, N; Morelli, M; Pinna, A

    2008-01-01

    Adenosine A(2A) receptors present in the central nervous system have been implicated in the modulation of motor functions. Accordingly, adenosine A(2A) receptor antagonists currently constitute an attractive non-dopaminergic option for use in the treatment of Parkinson's disease (PD). The highly enriched distributions of adenosine A(2A) receptors in striatopallidal neurons, and their ability to form functional heteromeric complexes with dopamine D(2) and metabotropic glutamate mGlu5 receptors, render A(2A) receptor antagonists of particular interest in the modulation of motor behavior, whilst at the same time displaying a low predisposition to inducing non-motor side effects. Furthermore, adenosine A(2A) receptor antagonists appear to exert a marked efficacy on PD tremor and in reducing the progress of underlying neurodegeneration and maladaptive neuroplasticity that complicates standard dopamine replacement treatments in PD. Finally, recent evidence has illustrated an improvement of cognitive function as well as enhancement of attention in rodents following administration of A(2A) receptor antagonists. This article is aimed at examining preclinical studies describing these findings as well as reports from clinical trials, in order to provide a comprehensive review of the evidence suggesting that this class of drugs may represent an advance in the treatment of PD.

  8. Study of the n-methyl-d-aspartate antagonistic properties of anticholinergic drugs

    Energy Technology Data Exchange (ETDEWEB)

    McDonough, J.H.; Shih, T.M.

    1995-12-31

    A study of the N-methyl-D-aspartate antagonistic properties of anticholinergic drugs. PHARMACOL BIOCHEM BEHAV. 51(2/3) 249-253, 1995. Drugs that act at the N-methyl-D-aspartate (NMDA) receptor complex have the ability to terminate nerve agent-induced seizures and modulate the neuropathologic consequences of agent exposure. Drugs with mixed anticholinergic and anti-NMDA properties potentially provide an ideal class of compounds for development as anticonvulsant treatments for nerve agent casualties. The present experiment evaluated the potential NMDA antagonist activity of 11 anticholinergic drugs by determining whether pretreatment with the compound was capable of protecting mice from the lethal effects of NMDA. The following anticholinergic drugs antagonized NMDA lethality and are ranked according to their potency: mecamylamine > procyclidine = benactyzine > biperiden > tribexyphenidyl. The anticholinergics atropine, aprophen, azaprophen, benztropine, 3-quinudidinyl benzilate (QNB), and scopolamine failed to show NMDA antagonist properties. In addition, and unexpectedly, diazepam, ethanol, and pentobarbital were also shown to be capable of antagonizing NMDA lethality over a certain range of doses. The advantages and limitations of using antagonism of NMDA lethality in mice as a bioassay for determining the NMDA antagonist properties of drugs are also discussed.

  9. Antibodies to the extracellular pore loop of TRPM8 act as antagonists of channel activation.

    Directory of Open Access Journals (Sweden)

    Silke Miller

    Full Text Available The mammalian transient receptor potential melastatin channel 8 (TRPM8 is highly expressed in trigeminal and dorsal root ganglia. TRPM8 is activated by cold temperature or compounds that cause a cooling sensation, such as menthol or icilin. TRPM8 may play a role in cold hypersensitivity and hyperalgesia in various pain syndromes. Therefore, TRPM8 antagonists are pursued as therapeutics. In this study we explored the feasibility of blocking TRPM8 activation with antibodies. We report the functional characterization of a rabbit polyclonal antibody, ACC-049, directed against the third extracellular loop near the pore region of the human TRPM8 channel. ACC-049 acted as a full antagonist at recombinantly expressed human and rodent TRPM8 channels in cell based agonist-induced 45Ca2+ uptake assays. Further, several poly-and monoclonal antibodies that recognize the same region also blocked icilin activation of not only recombinantly expressed TRPM8, but also endogenous TRPM8 expressed in rat dorsal root ganglion neurons revealing the feasibility of generating monoclonal antibody antagonists. We conclude that antagonist antibodies are valuable tools to investigate TRPM8 function and may ultimately pave the way for development of therapeutic antibodies.

  10. A SOCS1/3 antagonist peptide protects mice against lethal infection with influenza A virus

    Directory of Open Access Journals (Sweden)

    Chulbul M. Ahmed

    2015-11-01

    Full Text Available We have developed an antagonist to suppressor of cytokine signaling 1 (SOCS1, pJAK2(1001-1013, that corresponds to the activation loop of the Janus kinase JAK2, which is the binding site for the kinase inhibitory region (KIR of SOCS1. Internalized pJAK2(1001-1013 inhibits SOCS1 and SOCS3. SOCS1 has been shown to be an influenza virus induced virulence factor that enhances infection of cells. The antagonist was protective in cell culture and in influenza virus PR8 lethally infected C57BL/6 mice. The SOCS antagonist also prevented adverse morbidity as assessed by parameters such as weight loss and drop in body temperature and showed potent induction of both the cellular and humoral immune responses to the influenza virus candidate universal antigen matrix protein 2 (M2e. The SOCS antagonist thus protected mice against lethal influenza virus infection and possessed potent adjuvancy against the M2e candidate influenza virus universal vaccine antigen.

  11. Ketamine effects on memory reconsolidation favor a learning model of delusions.

    Directory of Open Access Journals (Sweden)

    Philip R Corlett

    Full Text Available Delusions are the persistent and often bizarre beliefs that characterise psychosis. Previous studies have suggested that their emergence may be explained by disturbances in prediction error-dependent learning. Here we set up complementary studies in order to examine whether such a disturbance also modulates memory reconsolidation and hence explains their remarkable persistence. First, we quantified individual brain responses to prediction error in a causal learning task in 18 human subjects (8 female. Next, a placebo-controlled within-subjects study of the impact of ketamine was set up on the same individuals. We determined the influence of this NMDA receptor antagonist (previously shown to induce aberrant prediction error signal and lead to transient alterations in perception and belief on the evolution of a fear memory over a 72 hour period: they initially underwent Pavlovian fear conditioning; 24 hours later, during ketamine or placebo administration, the conditioned stimulus (CS was presented once, without reinforcement; memory strength was then tested again 24 hours later. Re-presentation of the CS under ketamine led to a stronger subsequent memory than under placebo. Moreover, the degree of strengthening correlated with individual vulnerability to ketamine's psychotogenic effects and with prediction error brain signal. This finding was partially replicated in an independent sample with an appetitive learning procedure (in 8 human subjects, 4 female. These results suggest a link between altered prediction error, memory strength and psychosis. They point to a core disruption that may explain not only the emergence of delusional beliefs but also their persistence.

  12. Ketamine Effects on Memory Reconsolidation Favor a Learning Model of Delusions

    Science.gov (United States)

    Gardner, Jennifer M.; Piggot, Jennifer S.; Turner, Danielle C.; Everitt, Jessica C.; Arana, Fernando Sergio; Morgan, Hannah L.; Milton, Amy L.; Lee, Jonathan L.; Aitken, Michael R. F.; Dickinson, Anthony; Everitt, Barry J.; Absalom, Anthony R.; Adapa, Ram; Subramanian, Naresh; Taylor, Jane R.; Krystal, John H.; Fletcher, Paul C.

    2013-01-01

    Delusions are the persistent and often bizarre beliefs that characterise psychosis. Previous studies have suggested that their emergence may be explained by disturbances in prediction error-dependent learning. Here we set up complementary studies in order to examine whether such a disturbance also modulates memory reconsolidation and hence explains their remarkable persistence. First, we quantified individual brain responses to prediction error in a causal learning task in 18 human subjects (8 female). Next, a placebo-controlled within-subjects study of the impact of ketamine was set up on the same individuals. We determined the influence of this NMDA receptor antagonist (previously shown to induce aberrant prediction error signal and lead to transient alterations in perception and belief) on the evolution of a fear memory over a 72 hour period: they initially underwent Pavlovian fear conditioning; 24 hours later, during ketamine or placebo administration, the conditioned stimulus (CS) was presented once, without reinforcement; memory strength was then tested again 24 hours later. Re-presentation of the CS under ketamine led to a stronger subsequent memory than under placebo. Moreover, the degree of strengthening correlated with individual vulnerability to ketamine's psychotogenic effects and with prediction error brain signal. This finding was partially replicated in an independent sample with an appetitive learning procedure (in 8 human subjects, 4 female). These results suggest a link between altered prediction error, memory strength and psychosis. They point to a core disruption that may explain not only the emergence of delusional beliefs but also their persistence. PMID:23776445

  13. Diphenyl Purine Derivatives as Peripherally Selective Cannabinoid Receptor 1 Antagonists

    Science.gov (United States)

    Fulp, Alan; Bortoff, Katherine; Zhang, Yanan; Seltzman, Herbert; Mathews, James; Snyder, Rodney; Fennell, Tim; Maitra, Rangan

    2015-01-01

    Cannabinoid receptor 1 (CB1) antagonists are potentially useful for the treatment of several diseases. However, clinical development of several CB1 antagonists was halted due to central nervous system (CNS)-related side effects including depression and suicidal ideation in some users. Recently, studies have indicated that selective regulation of CB1 receptors in the periphery is a viable strategy for treating several important disorders. Past efforts to develop peripherally selective antagonists of CB1 have largely targeted rimonabant, an inverse agonist of CB1. Reported here are our efforts toward developing a peripherally selective CB1 antagonist based on the otenabant scaffold. Even though otenabant penetrates the CNS, it is unique among CB1 antagonists that have been clinically tested because it has properties that are normally associated with peripherally selective compounds. Our efforts have resulted in an orally absorbed compound that is a potent and selective CB1 antagonist with limited penetration into the CNS. PMID:23098108

  14. Hypocretin antagonists in insomnia treatment and beyond.

    Science.gov (United States)

    Ruoff, Chad; Cao, Michelle; Guilleminault, Christian

    2011-01-01

    Hypocretin neuropeptides have been shown to regulate transitions between wakefulness and sleep through stabilization of sleep promoting GABAergic and wake promoting cholinergic/monoaminergic neural pathways. Hypocretin also influences other physiologic processes such as metabolism, appetite, learning and memory, reward and addiction, and ventilatory drive. The discovery of hypocretin and its effect upon the sleep-wake cycle has led to the development of a new class of pharmacologic agents that antagonize the physiologic effects of hypocretin (i.e. hypocretin antagonists). Further investigation of these agents may lead to novel therapies for insomnia without the side-effect profile of currently available hypnotics (e.g. impaired cognition, confusional arousals, and motor balance difficulties). However, antagonizing a system that regulates the sleep-wake cycle while also influencing non-sleep physiologic processes may create an entirely different but equally concerning side-effect profile such as transient loss of muscle tone (i.e. cataplexy) and a dampened respiratory drive. In this review, we will discuss the discovery of hypocretin and its receptors, hypocretin and the sleep-wake cycle, hypocretin antagonists in the treatment of insomnia, and other implicated functions of the hypocretin system.

  15. Sexually antagonistic selection in human male homosexuality.

    Directory of Open Access Journals (Sweden)

    Andrea Camperio Ciani

    Full Text Available Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling 'Darwinian paradox'. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness, accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait.

  16. Sexually Antagonistic Selection in Human Male Homosexuality

    Science.gov (United States)

    Camperio Ciani, Andrea; Cermelli, Paolo; Zanzotto, Giovanni

    2008-01-01

    Several lines of evidence indicate the existence of genetic factors influencing male homosexuality and bisexuality. In spite of its relatively low frequency, the stable permanence in all human populations of this apparently detrimental trait constitutes a puzzling ‘Darwinian paradox’. Furthermore, several studies have pointed out relevant asymmetries in the distribution of both male homosexuality and of female fecundity in the parental lines of homosexual vs. heterosexual males. A number of hypotheses have attempted to give an evolutionary explanation for the long-standing persistence of this trait, and for its asymmetric distribution in family lines; however a satisfactory understanding of the population genetics of male homosexuality is lacking at present. We perform a systematic mathematical analysis of the propagation and equilibrium of the putative genetic factors for male homosexuality in the population, based on the selection equation for one or two diallelic loci and Bayesian statistics for pedigree investigation. We show that only the two-locus genetic model with at least one locus on the X chromosome, and in which gene expression is sexually antagonistic (increasing female fitness but decreasing male fitness), accounts for all known empirical data. Our results help clarify the basic evolutionary dynamics of male homosexuality, establishing this as a clearly ascertained sexually antagonistic human trait. PMID:18560521

  17. The alpha7 nicotinic acetylcholine receptor-selective antagonist, methyllycaconitine, partially protects against beta-amyloid1-42 toxicity in primary neuron-enriched cultures.

    Science.gov (United States)

    Martin, Shelley E; de Fiebre, Nancy Ellen C; de Fiebre, Christopher M

    2004-10-01

    Studies have suggested that the neuroprotective actions of alpha7 nicotinic agonists arise from activation of receptors and not from the extensive desensitization which rapidly follows activation. Here, we report that the alpha7-selective nicotinic antagonist, methyllycaconitine (MLA), protects against beta-amyloid-induced neurotoxicity; whereas the alpha4beta2-selective antagonist, dihydro-beta-erythroidine, does not. These findings suggest that neuroprotective actions of alpha7-acting agents arise from receptor inhibition/desensitization and that alpha7 antagonists may be useful neuroprotective agents.

  18. Iontophoresis of endothelin receptor antagonists in rats and men.

    Directory of Open Access Journals (Sweden)

    Matthieu Roustit

    Full Text Available The treatment of scleroderma-related digital ulcers is challenging. The oral endothelin receptor antagonist (ERA bosentan has been approved but it may induce liver toxicity. The objective of this study was to test whether ERAs bosentan and sitaxentan could be locally delivered using iontophoresis.Cathodal and anodal iontophoresis of bosentan and sitaxentan were performed on anaesthetized rat hindquarters without and during endothelin-1 infusion. Skin blood flow was quantified using laser-Doppler imaging and cutaneous tolerability was assessed. Iontophoresis of sitaxentan (20 min, 20 or 100 µA was subsequently performed on the forearm skin of healthy men (n = 5.In rats neither bosentan nor sitaxentan increased skin blood flux compared to NaCl. When simultaneously infusing endothelin-1, cathodal iontophoresis of sitaxentan increased skin blood flux compared to NaCl (AUC(0-20 were 44032.2 ± 12277 and 14957.5 ± 23818.8 %BL.s, respectively; P = 0.01. In humans, sitaxentan did not significantly increase skin blood flux as compared to NaCl. Iontophoresis of ERAs was well tolerated both in animals and humans.This study shows that cathodal iontophoresis of sitaxentan but not bosentan partially reverses endothelin-induced skin vasoconstriction in rats, suggesting that sitaxentan diffuses into the dermis. However, sitaxentan does not influence basal skin microvascular tone in rats or in humans.

  19. Anticonvulsant and reproductive toxicological studies of the imidazole-based histamine H3R antagonist 2-18 in mice

    Directory of Open Access Journals (Sweden)

    Bastaki SM

    2018-01-01

    Full Text Available Salim M Bastaki,1 Yousef M Abdulrazzaq,2 Mohamed Shafiullah,1 Małgorzata Więcek,3 Katarzyna Kieć-Kononowicz,3 Bassem Sadek1 1Department of Pharmacology and Therapeutics, College of Medicine and Health Science, United Arab Emirates University, Al Ain, 2Department of Medical Education, Dubai Health Authority, Dubai, UAE; 3Department of Technology and Biotechnology of Drugs, Faculty of Pharmacy, Jagiellonian University Medical College, Medyczna, Kraków, Poland Abstract: The imidazole-based H3R antagonist 2-18 with high in vitro H3R antagonist affinity, excellent in vitro selectivity profile, and high in vivo H3R antagonist potency was tested for its anticonvulsant effect in maximal electroshock (MES-induced convulsions in mice having valproic acid (VPA as a reference antiepileptic drug (AED. Additionally, H3R antagonist 2-18 was evaluated for its reproductive toxicity in the same animal species. The results show that acute systemic administration (intraperitoneal; i.p. of H3R antagonist 2-18 (7.5, 15, 30, and 60 mg/kg, i.p. significantly and dose dependently protected male as well as female mice against MES-induced convulsion. The protective action observed for H3R antagonist 2-18 in both mice sexes was comparable to that of VPA and was reversed when mice were pretreated with the selective H3R agonist (R-alpha-methylhistamine (RAMH, 10 mg/kg, i.p.. Moreover, the results show that acute systemic administration of single (7.5, 15, 30, or 60 mg/kg, i.p. or multiple doses (15×3 mg/kg, i.p. of H3R antagonist 2-18 on gestation day (GD 8 or 13 did not affect the maternal body weight of mice when compared with the control group. Furthermore, no significant differences were observed in the average number of implantations and resorptions between the control and H3R antagonist 2-18-treated group at the early stages of gestation and the organogenesis period. However, oral treatment with H3R antagonist 2-18 (15 mg/kg on GD 8 induced a reduced number of

  20. 8-Azaxanthine derivatives as antagonists of adenosine receptors.

    Science.gov (United States)

    Franchetti, P; Messini, L; Cappellacci, L; Grifantini, M; Lucacchini, A; Martini, C; Senatore, G

    1994-09-02

    A series of 1,3-dimethyl- and 1,3-dipropyl-8-azaxanthines, substituted at the N8 or N7 position with substituents which usually increase the affinity of the xanthines for the adenosine receptors, was synthesized and studied in radioligand binding experiments. The substitution of CH with N at the 8-position of both theophylline and caffeine dramatically reduced the affinity, as demonstrated by the fact that 8-azatheophylline and 8-azacaffeine were inert. The introduction of a methyl group at 8-position of 8-azatheophylline restored the antagonistic activity at A2 receptors, while a 8-cycloalkyl substituent increased the affinity for both receptor subtypes. A more favorable effect on affinity was produced by the substitution of the 7-methyl group in 8-azacaffeine with cycloalkyl groups. 7-Cyclopentyl-1,3-dimethyl-8-azaxanthine was 3 times more potent than caffeine at A1 receptors and 6 times less active at A2 receptors. On the contrary, the 7-cyclohexyl-1,3-dimethyl-8-azaxanthine was more potent than caffeine at A2 receptors. The substitution of 1- and 3-methyl groups with propyl in both 7- and 8-substituted 8-azatheophylline increased remarkably the affinity for A1 receptors. The 7-cyclopentyl-1,3-dipropyl-8-azaxanthine appears to be one of the most potent and selective among 7-alkyl-substituted xanthines at A1 receptors so far known. Because the 8-aza analogues of 8-substituted 1,3-dialkylxanthine were in any case less active than the corresponding xanthine derivatives, it was confirmed that the hydrogen atom at the 7-position of xanthines plays an important role in the binding to adenosine receptors.

  1. Novel aspinolide production by Trichoderma arundinaceum with a potential role in Botrytis cinerea antagonistic activity and plant defense priming

    Science.gov (United States)

    Harzianum A (HA), a trichothecene produced by Trichoderma arundinaceum, has recently been described to have antagonistic activity against fungal plant pathogens and to induce plant defence genes. In the present work, we have shown that a tri5 genedisrupted mutant that lacks HA production overproduce...

  2. Anticonvulsant effects of isomeric nonimidazole histamine H3 receptor antagonists

    Directory of Open Access Journals (Sweden)

    Sadek B

    2016-11-01

    Full Text Available Bassem Sadek,1 Ali Saad,1 Johannes Stephan Schwed,2,3 Lilia Weizel,2 Miriam Walter,2 Holger Stark2,3 1Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, Al Ain, United Arab Emirates; 2Biocenter, Institute of Pharmaceutical Chemistry, Goethe University, Frankfurt, Germany; 3Department of Pharmaceutical and Medicinal Chemistry, Institute of Pharmaceutical and Medicinal Chemistry, Heinrich Heine University, Düsseldorf, Germany Abstract: Phenytoin (PHT, valproic acid, and modern antiepileptic drugs (AEDs, eg, remacemide, loreclezole, and safinamide, are only effective within a maximum of 70%–80% of epileptic patients, and in many cases the clinical use of AEDs is restricted by their side effects. Therefore, a continuous need remains to discover innovative chemical entities for the development of active and safer AEDs. Ligands targeting central histamine H3 receptors (H3Rs for epilepsy might be a promising therapeutic approach. To determine the potential of H3Rs ligands as new AEDs, we recently reported that no anticonvulsant effects were observed for the (S-2-(4-(3-(piperidin-1-ylpropoxybenzylaminopropanamide (1. In continuation of our research, we asked whether anticonvulsant differences in activities will be observed for its R-enantiomer, namely, (R-2-(4-(3-(piperidin-1-ylpropoxybenzylaminopropaneamide (2 and analogs thereof, in maximum electroshock (MES-, pentylenetetrazole (PTZ-, and strychnine (STR-induced convulsion models in rats having PHT and valproic acid (VPA as reference AEDs. Unlike the S-enantiomer (1, the results show that animals pretreated intraperitoneally (ip with the R-enantiomer 2 (10 mg/kg were moderately protected in MES and STR induced models, whereas proconvulsant effect was observed for the same ligand in PTZ-induced convulsion models. However, animals pretreated with intraperitoneal doses of 5, 10, or 15 mg/kg of structurally bulkier (R-enantiomer (3

  3. Favorable Vascular Actions of Angiotensin-(1-7) in Human Obesity.

    Science.gov (United States)

    Schinzari, Francesca; Tesauro, Manfredi; Veneziani, Augusto; Mores, Nadia; Di Daniele, Nicola; Cardillo, Carmine

    2018-01-01

    Obese patients have vascular dysfunction related to impaired insulin-stimulated vasodilation and increased endothelin-1-mediated vasoconstriction. In contrast to the harmful vascular actions of angiotensin (Ang) II, the angiotensin-converting enzyme 2 product Ang-(1-7) has shown to exert cardiovascular and metabolic benefits in experimental models through stimulation of the Mas receptor. We, therefore, examined the effects of exogenous Ang-(1-7) on vasodilator tone and endothelin-1-dependent vasoconstriction in obese patients. Intra-arterial infusion of Ang-(1-7) (10 nmol/min) resulted in significant increase in unstimulated forearm flow ( P =0.03), an effect that was not affected by the Mas receptor antagonist A779 (10 nmol/min; P >0.05). In the absence of hyperinsulinemia, however, forearm flow responses to graded doses of acetylcholine and sodium nitroprusside were not different during Ang-(1-7) administration compared with saline (both P >0.05). During infusion of regular insulin (0.15 mU/kg per minute), by contrast, endothelium-dependent vasodilator response to acetylcholine was significantly enhanced by Ang-(1-7) ( P =0.04 versus saline), whereas endothelium-independent response to sodium nitroprusside was not modified ( P =0.91). Finally, Ang-(1-7) decreased the vasodilator response to endothelin A receptor blockade (BQ-123; 10 nmol/min) compared with saline (6±1% versus 93±17%; P <0.001); nitric oxide inhibition by l- N -monomethylarginine (4 µmol/min) during concurrent endothelin A antagonism resulted in similar vasoconstriction in the absence or presence of Ang-(1-7 Ang-(1-7) ( P =0.69). Our findings indicate that in obese patients Ang-(1-7) has favorable effects not only to improve insulin-stimulated endothelium-dependent vasodilation but also to blunt endothelin-1-dependent vasoconstrictor tone. These findings provide support for targeting Ang-(1-7) to counteract the hemodynamic abnormalities of human obesity. © 2017 American Heart Association, Inc.

  4. Nonsupplemented luteal phase characteristics after the administration of recombinant human chorionic gonadotropin, recombinant luteinizing hormone, or gonadotropin-releasing hormone (GnRH) agonist to induce final oocyte maturation in in vitro fertilization patients after ovarian stimulation with recombinant follicle-stimulating hormone and GnRH antagonist cotreatment

    NARCIS (Netherlands)

    N.S. Macklon (Nick); M.J.C. Eijkemans (René); M. Ludwig (Michael); R.E. Felberbaum; K. Diedrich; S. Bustion; E. Loumaye; B.C.J.M. Fauser (Bart); N.G.M. Beckers (Nicole)

    2003-01-01

    textabstractReplacing GnRH agonist cotreatment for the prevention of a premature rise in LH during ovarian stimulation for in vitro fertilization (IVF) by the late follicular phase administration of GnRH antagonist may render supplementation of the luteal phase redundant, because

  5. Quick epinephrine administration induces favorable neurological outcomes in out-of-hospital cardiac arrest patients.

    Science.gov (United States)

    Ueta, H; Tanaka, H; Tanaka, S; Sagisaka, R; Takyu, H

    2017-05-01

    This research is to study if quick administration of adrenaline on OHCA prior to hospitalization has an effect on improving CPC1-2 at one month. A total 13,326 cases were extracted from 2011 to 2014 Utstein data for this retrospective cohort study, also, EMT reached the patients within 16min after 119 called and adrenaline was then administered within 22min of after contact. Patients were contacted within 8min of the 119 call (n=6956), and were contacted between 8 and 16min after the call (n=6370). Further divided into groups in which the adrenaline was administered within/without 10min after contact. Primary outcome was the rate of a good prognosis for cerebral performance (CPC1-2) at 1 month and secondary outcome was the return of spontaneous circulation (ROSC) rate. The odds ratio of the CPC1-2 at 1month by the EMS reached within 8min after 119 call and then adrenaline administered within 10min was 2.12 (1.54-2.92).Those reached between 8 and 16min was 2.66 (1.97-3.59). However, the ROSC rate was 2.00 (1.79-2.25) for those reached within 8min and also 2.00 (1.79-2.25) for those reached between 8min and 16min. In cases of OHCA, it appears that the CPC1-2 rate after 1month can be improved even in cases where the victim is reached >8min after the 119 call, as long as the victim is reached within 16min and emergency responders administer the adrenaline as quickly as possible. Copyright © 2017 Elsevier Inc. All rights reserved.

  6. Internalization of the chemokine receptor CCR4 can be evoked by orthosteric and allosteric receptor antagonists.

    Science.gov (United States)

    Ajram, Laura; Begg, Malcolm; Slack, Robert; Cryan, Jenni; Hall, David; Hodgson, Simon; Ford, Alison; Barnes, Ashley; Swieboda, Dawid; Mousnier, Aurelie; Solari, Roberto

    2014-04-15

    The chemokine receptor CCR4 has at least two natural agonist ligands, MDC (CCL22) and TARC (CCL17) which bind to the same orthosteric site with a similar affinity. Both ligands are known to evoke chemotaxis of CCR4-bearing T cells and also elicit CCR4 receptor internalization. A series of small molecule allosteric antagonists have been described which displace the agonist ligand, and inhibit chemotaxis. The aim of this study was to determine which cellular coupling pathways are involved in internalization, and if antagonists binding to the CCR4 receptor could themselves evoke receptor internalization. CCL22 binding coupled CCR4 efficiently to β-arrestin and stimulated GTPγS binding however CCL17 did not couple to β-arrestin and only partially stimulated GTPγS binding. CCL22 potently induced internalization of almost all cell surface CCR4, while CCL17 showed only weak effects. We describe four small molecule antagonists that were demonstrated to bind to two distinct allosteric sites on the CCR4 receptor, and while both classes inhibited agonist ligand binding and chemotaxis, one of the allosteric sites also evoked receptor internalization. Furthermore, we also characterize an N-terminally truncated version of CCL22 which acts as a competitive antagonist at the orthosteric site, and surprisingly also evokes receptor internalization without demonstrating any agonist activity. Collectively this study demonstrates that orthosteric and allosteric antagonists of the CCR4 receptor are capable of evoking receptor internalization, providing a novel strategy for drug discovery against this class of target. Copyright © 2014 The Authors. Published by Elsevier B.V. All rights reserved.

  7. CysLT(1)R antagonists inhibit tumor growth in a xenograft model of colon cancer.

    Science.gov (United States)

    Savari, Sayeh; Liu, Minghui; Zhang, Yuan; Sime, Wondossen; Sjölander, Anita

    2013-01-01

    The expression of the inflammatory G-protein coupled receptor CysLT1R has been shown to be upregulated in colon cancer patients and associated with poor prognosis. The present study investigated the correlation between CysLT1R and colon cancer development in vivo using CysLT1R antagonists (ZM198,615 or Montelukast) and the nude mouse xenograft model. Two drug administration regimens were established. The first regimen was established to investigate the importance of CysLT1R in tumor initiation. Nude mice were inoculated with 50 µM CysLT1R antagonist-pretreated HCT-116 colon cancer cells and received continued treatment (5 mg/kg/day, intraperitoneally). The second regimen aimed to address the role of CysLT1R in tumor progression. Nude mice were inoculated with non-pretreated HCT-116 cells and did not receive CysLT1R antagonist treatment until recordable tumor appearance. Both regimens resulted in significantly reduced tumor size, attributed to changes in proliferation and apoptosis as determined by reduced Ki-67 levels and increased levels of p21(WAF/Cip1) (Pcolon cancer cell line HCT-116 and CysLT1R antagonists. In addition to significant reductions in cell proliferation, adhesion and colony formation, we observed induction of cell cycle arrest and apoptosis in a dose-dependent manner. The ability of Montelukast to inhibit growth of human colon cancer xenograft was further validated by using two additional colon cancer cell lines, SW-480 and HT-29. Our results demonstrate that CysLT1R antagonists inhibit growth of colon cancer xenografts primarily by reducing proliferation and inducing apoptosis of the tumor cells.

  8. Antagonist Functional Selectivity: 5-HT2A Serotonin Receptor Antagonists Differentially Regulate 5-HT2A Receptor Protein Level In Vivo

    Science.gov (United States)

    Yadav, Prem N.; Kroeze, Wesley K.; Farrell, Martilias S.

    2011-01-01

    Dysregulation of the 5-HT2A receptor is implicated in both the etiology and treatment of schizophrenia. Although the essential role of 5-HT2A receptors in atypical antipsychotic drug actions is widely accepted, the contribution of 5-HT2A down-regulation to their efficacy is not known. We hypothesized that down-regulation of cortical 5-HT2A receptors contributes to the therapeutic action of atypical antipsychotic drugs. To test this hypothesis, we assessed the effect of chronically administered antipsychotics (clozapine, olanzapine, and haloperidol) and several 5-HT2A antagonists [ketanserin, altanserin, α-(2,3-dimethoxyphenyl)-1-[2-(4-fluorophenylethyl)]-4-piperidinemethanol (M100907), α-phenyl-1-(2-phenylethyl)-4-piperidinemethano (M11939), 4-[(2Z)-3-{[2-(dimethylamino)ethoxy]amino}-3-(2-fluorophenyl)prop-2-en-1-ylidene]cyclohexa-2,5-dien-1-one (SR46349B), and pimavanserin], on the phencyclidine (PCP)-induced hyperlocomotor response and cortical 5-HT2A receptor levels in C57BL/6J mice. Clozapine and olanzapine, but not haloperidol, induced receptor down-regulation and attenuated PCP-induced locomotor responses. Of the selective 5-HT2A antagonists tested, only ketanserin caused significant receptor protein down-regulation, whereas SR46349B up-regulated 5-HT2A receptors and potentiated PCP-hyperlocomotion; the other 5-HT2A receptor antagonists were without effect. The significance of these findings with respect to atypical antipsychotic drug action is discussed. PMID:21737536

  9. Assay method for organic calcium antagonist drugs and a kit for such an assay

    International Nuclear Information System (INIS)

    Snyder, S. H.; Gould, R. J.

    1985-01-01

    A method for measuring the level of organic calcium antagonist drug in a body fluid comprises preparing a mixture of a radioactive calcium antagonist drug, a body fluid containing a calcium antagonist drug and a calcium antagonist receptor material, measuring the radioactivity of the radioactive calcium antagonist drug bound to said calcium antagonist receptor material and deriving the concentration of the calcium antagonist drug in the body fluid from a standard curve indicating the concentration of calcium antagonist drug versus inhibition of binding of said radioactive calcium antagonist drug to said receptor sites caused by the calcium antagonist drug in said body fluid. A kit for measuring the level of an organic calcium drug comprises a receptacle containing a radioactive calcium antagonist drug, a calcium antagonist receptor material and a standard amount of a nonradioactive calcium antagonist drug

  10. Antagonistic activity of marine sponges associated Actinobacteria

    Directory of Open Access Journals (Sweden)

    Selvakumar Dharmaraj

    2016-06-01

    Full Text Available Objective: To focus on the isolation and preliminary characterization of marine sponges associated Actinobacteria particularly Streptomyces species and also their antagonistic activities against bacterial and fungal pathogens. Methods: The sponges were collected from Kovalam and Vizhinjam port of south-west coast of Kerala, India. Isolation of strains was carried out from sponge extracts using international Streptomyces project media. For preliminary identification of the strains, morphological (mycelial colouration, soluble pigments, melanoid pigmentation, spore morphology, nutritional uptake (carbon utilisation, amonoacids influence, sodium chloride tolerance, physiological (pH, temperature and chemotaxonomical characterization were done. Antimicrobial studies were also carried out for the selected strains. Results: With the help of the spicule structures, the collected marine sponges were identified as Callyspongia diffusa, Mycale mytilorum, Tedania anhelans and Dysidea fragilis. Nearly 94 strains were primarily isolated from these sponges and further they were sub-cultured using international Streptomyces project media. The strains exhibited different mycelial colouration (aerial and substrate, soluble and melanoid pigmentations. The strains possessed three types of sporophore morphology namely rectus flexibilis, spiral and retinaculiaperti. Among the 94 isolates, seven exhibited antibacterial and antifungal activities with maximal zone of inhibition of 30 mm. The nutritional, physiological and chemotaxonomical characteristic study helped in the conventional identification of the seven strains and they all suggest that the strains to be grouped under the genus Streptomyces. Conclusions: The present study clearly helps in the preliminary identification of the isolates associated with marine sponges. Antagonistic activities prove the production of antimicrobial metabolites against the pathogens. Marine sponges associated Streptomyces are

  11. Evidence against the unitary hypothesis of agonist and antagonist action at presynaptic adrenoceptors.

    Science.gov (United States)

    Kalsner, S.

    1982-01-01

    1 The concept that presynaptic receptors regulate noradrenergic transmitter release via a system of inhibitory receptors mediating negative feedback relies on a supposed association between increases in stimulation-induced efflux of [3H]-noradrenaline by antagonists and blockade by them of the inhibitory effects of exogenous noradrenaline. 2 It was shown in guinea-pig ureter, that yohimbine (3 X 10(-7)M), a presumed selective presynaptic antagonist, increased transmitter efflux substantially at 1 Hz and 5 Hz with 100 pulses, purportedly representing antagonism of the inhibitory effect of locally released noradrenaline but did not reduce the inhibitory effect of exogenous noradrenaline (1.8 X 10(-6)M or 1.8 X 10(-7)M) except in one case. 3 Additionally, the inhibitory effect of oxymetazoline (1.0 X 10(-7)M or 1.0 X 10(-8)M) on stimulation-induced efflux was in no way antagonized by yohimbine (3 X 10(-7)M). 4 It is concluded that the increased efflux of [3H]-noradrenaline produced by antagonists and the decreased efflux produced by exogenous agonists may represent actions at different loci and that the hypothesis of presynaptic feedback regulatory sites is still not substantiated. PMID:6128040

  12. Rolapitant for the treatment of chemotherapy-induced nausea and vomiting.

    Science.gov (United States)

    Navari, Rudolph M

    2015-01-01

    Chemotherapy-induced nausea and vomiting is a significant clinical issue which affects patient's quality of life and treatment decisions. Significant improvements in the control of chemotherapy-induced nausea and vomiting have occurred in the past 15 years with the introduction of new antiemetic agents 5-HT3, receptor antagonists, neurokinin-1 (NK-1) receptor antagonists, and olanzapine. Aprepitant was the first NK-1 receptor antagonist introduced (2003) for the prevention of chemotherapy-induced nausea and vomiting in combination with a 5-HT3 receptor antagonist and dexamethasone. A second NK-1 receptor antagonist netupitant was approved for use in October 2014. Phase III clinical trials of an additional NK-1 receptor antagonist rolapitant have been completed, and the data have been submitted for regulatory approval. A description of rolapitant and its role in chemotherapy-induced nausea and vomiting will be presented, along with a comparison of the other neurolinin-1 receptor antagonists aprepitant and netupitant.

  13. Effect of a Hypocretin/Orexin Antagonist on Neurocognitive Performance

    Science.gov (United States)

    2013-12-18

    Effectiveness Directorate, Biosciences and Protection Division, Warfighter Fatigue Countermeasures Branch. 35. Golden, C.J. (1978). Stroop Color and Word Test: A...0080 TITLE: Effect of a Hypocretin/Orexin Antagonist on Neurocognitive Performance PRINCIPAL INVESTIGATOR: Dr. Thomas Neylan...31August2013 4. TITLE AND SUBTITLE Effect of a Hypocretin/Orexin Antagonist on Neurocognitive Performance 5a. CONTRACT NUMBER W81XWH

  14. Using waste of Tofu production improved antagonistic activities of a ...

    African Journals Online (AJOL)

    Mrs. Hoa

    2012-10-04

    Oct 4, 2012 ... screened for their antagonistic activity against 10 races of Xoo causing rice bacterial blight disease. Three actinomycete strains ... antagonistic activity of VN10-A-44 against the Xoo pathogen and to make use of tofu waste for large- ..... vitamins and some essential amino acids which are very important for ...

  15. Evaluation of antagonistic fungi against charcoal rot of sunflower ...

    African Journals Online (AJOL)

    In vitro, sensitivity of Macrophomina phaseolina (Tassi) Goid determined through inhibition zone technique to various antagonistic fungi viz., Aspergillus niger, Aspergillus flavus, Trichoderma viride, Trichoderma harzianum and Penicillium capsulatum amended into PDA medium. All the antagonists reduced the colony ...

  16. Calcium antagonists for ischemic stroke: a systematic review

    NARCIS (Netherlands)

    Horn, J.; Limburg, M.

    2001-01-01

    BACKGROUND AND PURPOSE: Stroke is a common disease, and many trials with calcium antagonists as possible neuroprotective agents have been conducted. The aim of this review is to determine whether calcium antagonists reduce the risk of death or dependency after acute ischemic stroke. METHODS: Acute

  17. Antagonistic and Bargaining Games in Optimal Marketing Decisions

    Science.gov (United States)

    Lipovetsky, S.

    2007-01-01

    Game theory approaches to find optimal marketing decisions are considered. Antagonistic games with and without complete information, and non-antagonistic games techniques are applied to paired comparison, ranking, or rating data for a firm and its competitors in the market. Mix strategy, equilibrium in bi-matrix games, bargaining models with…

  18. Interaction between Antagonist of Cannabinoid Receptor and Antagonist of Adrenergic Receptor on Anxiety in Male Rat

    Directory of Open Access Journals (Sweden)

    Alireza Komaki

    2014-07-01

    Full Text Available Introduction: Anxiety is among the most common and treatable mental disorders. Adrenergic and cannabinoid systems have an important role in the neurobiology of anxiety. The elevated plus-maze (EPM has broadly been used to investigate anxiolytic and anxiogenic compounds. The present study investigated the effects of intraperitoneal (IP injection of cannabinoid CB1 receptor antagonist (AM251 in the presence of alpha-1 adrenergic antagonist (Prazosin on rat behavior in the EPM. Methods: In this study, the data were obtained from male Wistar rat, which weighing 200- 250 g. Animal behavior in EPM were videotaped and saved in computer for 10 min after IP injection of saline, AM251 (0.3 mg/kg, Prazosin (0.3 mg/kg and AM251 + Prazosin, subsequently scored for conventional indices of anxiety. During the test period, the number of open and closed arms entries, the percentage of entries into the open arms of the EPM, and the spent time in open and closed arms were recorded. Diazepam was considered as a positive control drug with anxiolytic effect (0.3, 0.6, 1.2 mg/kg. Results: Diazepam increased the number of open arm entries and the percentage of spent time on the open arms. IP injection of AM251 before EPM trial decreased open arms exploration and open arm entry. Whereas, Prazosin increased open arms exploration and open arm entry. This study showed that both substances in simultaneous injection have conflicting effects on the responses of each of these two compounds in a single injection. Discussion: Injection of CB1 receptor antagonist may have an anxiogenic profile in rat, whereas adrenergic antagonist has an anxiolytic effect. Further investigations are essential for better understanding of anxiolytic and anxiogenic properties and neurobiological mechanisms of action and probable interactions of the two systems.

  19. NMDA antagonists exert distinct effects in experimental organophosphate or carbamate poisoning in mice

    International Nuclear Information System (INIS)

    Dekundy, Andrzej; Kaminski, Rafal M.; Zielinska, Elzbieta; Turski, Waldemar A.

    2007-01-01

    Organophosphate (OP) and carbamate acetylcholinesterase (AChE) inhibitors produce seizures and lethality in mammals. Anticonvulsant and neuroprotective properties of N-methyl-D-aspartate (NMDA) antagonists encourage the investigation of their effects in AChE inhibitor-induced poisonings. In the present study, the effects of dizocilpine (MK-801, 1 mg/kg) or 3-((RS)-2-carboxypiperazin-4-yl)-propyl-1-phosphonic acid (CPP, 10 mg/kg), alone or combined with muscarinic antagonist atropine (1.8 mg/kg), on convulsant and lethal properties of an OP pesticide dichlorvos or a carbamate drug physostigmine, were studied in mice. Both dichlorvos and physostigmine induced dose-dependent seizure activity and lethality. Atropine did not prevent the occurrence of convulsions but decreased the lethal effects of both dichlorvos and physostigmine. MK-801 or CPP blocked or attenuated, respectively, dichlorvos-induced convulsions. Contrariwise, NMDA antagonists had no effect in physostigmine-induced seizures or lethality produced by dichlorvos or physostigmine. Concurrent pretreatment with atropine and either MK-801 or CPP blocked or alleviated seizures produced by dichlorvos, but not by physostigmine. Both MK-801 and CPP co-administered with atropine enhanced its antilethal effects in both dichlorvos and physostigmine poisoning. In both saline- and AChE inhibitor-treated mice, no interaction of the investigated antidotes with brain cholinesterase was found. The data indicate that both muscarinic ACh and NMDA receptor-mediated mechanisms contribute to the acute toxicity of AChE inhibitors, and NMDA receptors seem critical to OP-induced seizures

  20. A novel antagonist of CRTH2 blocks eosinophil release from bone marrow, chemotaxis and respiratory burst

    DEFF Research Database (Denmark)

    Royer, J F; Schratl, P; Lorenz, S

    2007-01-01

    developed small molecule antagonist of CRTH2, Cay10471, on eosinophil function with respect to recruitment, respiratory burst and degranulation. METHODS: Chemotaxis of guinea pig bone marrow eosinophils and human peripheral blood eosinophils were determined using microBoyden chambers. Eosinophil release...... from bone marrow was investigated in the in situ perfused guinea pig hind limb preparation. Respiratory burst and degranulation were measured by flow cytometry. RESULTS: Cay10471 bound with high affinity to recombinant human and guinea pig CRTH2, but not DP, receptors. The antagonist prevented the PGD......(2)-induced release of eosinophils from guinea pig bone marrow, and inhibited the chemotaxis of guinea pig bone marrow eosinophils and human peripheral blood eosinophils. Pretreatment with PGD(2) primed eosinophils for chemotaxis towards eotaxin, and this effect was prevented by Cay10471. In contrast...

  1. PAF receptor antagonist Ginkgolide B inhibits tumourigenesis and angiogenesis in colitis-associated cancer.

    Science.gov (United States)

    Sun, Lei; He, Zhen; Ke, Jia; Li, Senmao; Wu, Xianrui; Lian, Lei; He, Xiaowen; He, Xiaosheng; Hu, Jiancong; Zou, Yifeng; Wu, Xiaojian; Lan, Ping

    2015-01-01

    Platelet activating factor (PAF), a potent pro-inflammatory phospholipid, has been found to trigger tumor growth and angiogenesis through its G-protein coupled receptor (PAFR). This study was aimed to investigate the potential role of PAF in azoxymethane (AOM)/dextran sulfate sodium (DSS) induced colitis-associated cancer (CAC), using PAFR antagonist Ginkgolide B (GKB). We found GKB up-regulated serum level of PAF-AH activity. As assessed by disease activity index (DAI), histological injury scores, leukocytes infiltration, and expression of pro-inflammatory cytokines, GKB ameliorated colonic inflammation and decreased tumor number and load in mice. GKB also decreased expression of vascular endothelial growth factor (VEGF) and microvessel density (MVD) in tumor. These results suggest that PAFR antagonist might be a potential therapeutic strategy for CAC.

  2. Mineralocorticoid Receptor Antagonists-A New Sprinkle of Salt and Youth.

    Science.gov (United States)

    Stojadinovic, Olivera; Lindley, Linsey E; Jozic, Ivan; Tomic-Canic, Marjana

    2016-10-01

    Skin atrophy and impaired cutaneous wound healing are the recognized side effects of topical glucocorticoid (GC) therapy. Although GCs have high affinity for the glucocorticoid receptor, they also bind and activate the mineralocorticoid receptor. In light of this, one can speculate that some of the GC-mediated side effects can be remedied by blocking activation of the mineralocorticoid receptor. Indeed, according to Nguyen et al., local inhibition of the mineralocorticoid receptor via antagonists (spironolactone, canrenoate, and eplerenone) rescues GC-induced delayed epithelialization and accelerates wound closure in diabetic animals by targeting epithelial sodium channels and stimulating keratinocyte proliferation. These findings suggest that the use of mineralocorticoid receptor antagonists coupled with GC therapy may be beneficial in overcoming at least some of the GC-mediated side effects. Copyright © 2016 The Authors. Published by Elsevier Inc. All rights reserved.

  3. Synthesis and testing of tetrodotoxin and batrachotoxin antagonists. Final report, 1 February 1986-15 September 1989

    Energy Technology Data Exchange (ETDEWEB)

    Toll, L.

    1990-03-12

    Compounds have been synthesized as potential antagonists to the neurotoxin batrachotoxin. The compounds synthesized have been examined for binding affinity at the batrachotoxin binding site in rat brain, and for ability to inhibit veratridine-stimulated (22)Na+ uptake into neuroblastoma cells. The compounds ranged in affinity from 2.7 to 200 micrometers. The compounds also varied in their abilities to stimulate or inhibit (22)Na+. The two highest affinity compounds proved to be complete antagonists, competitively inhibiting both basal- and veratridine-stimulated (22)Na+ uptake. Neither of these compounds protected against batrachotoxin-induced lethality in mice. We have also made some progress in the synthesis of potential antagonists to the neurotoxin tetrodotoxin.

  4. Effects of a NR2B Selective NMDA Glutamate Antagonist, CP-101,606, on Dyskinesia and Parkinsonism

    Science.gov (United States)

    Nutt, John G.; Gunzler, Steven A; Kirchhoff, Trish; Hogarth, Penelope; Weaver, Jerry L.; Krams, Michael; Jamerson, Brenda; Menniti, Frank S.; Landen, Jaren W.

    2011-01-01

    Glutamate antagonists decrease dyskinesia and augment the antiparkinsonian effects of levodopa in animal models of Parkinson’s disease (PD). In a randomized, double-blind, placebo-controlled clinical trial we investigated the acute effects of placebo and two doses of a NR2B subunit selective NMDA glutamate antagonist, CP-101,606, on the response to two-hour levodopa infusions in 12 PD subjects with motor fluctuations and dyskinesia. Both doses of CP-101,606 reduced the maximum severity of levodopa-induced dyskinesia approximately 30% but neither dose improved parkinsonism. CP-101,606 was associated with a dose-related dissociation and amnesia. These results support the hypothesis that glutamate antagonists may be useful antidyskinetic agents. However, future studies will have to determine if the benefits of dyskinesia suppression can be achieved without adverse cognitive effects. PMID:18759356

  5. Efeito analgésico de antagonistas do receptor da histamina H1 em modelo de dor provocada por formalina em ratos Efecto analgésico de antagonistas del receptor de la histamina H1 en un modelo de dolor provocado por formalina en ratones Analgesic effects of H1 receptor antagonists in the rat model of formalin-induced pain

    Directory of Open Access Journals (Sweden)

    Hazem Adel Ashmawi

    2009-08-01

    different H1 receptor antagonists (pyrilamine, promethazine, and cetirizine administered directly in the paw of the rat, intraperitoneally, or in peripheral nerve blockade in the formalin-induced pain model. The effects of the drugs on the number of paw elevations were observed. RESULTS: In phase I, the local administration of pyrilamine caused a dose-dependent reduction on the number of paw elevations; in the highest dose, the number of paw elevations was reduced by 97.8%. Promethazine decreased it by 92%, while cetirizine decreased by 23.9%. In phase II, pyrilamine decreased the number of paw elevations by 93.5%, promethazine by 78.2%, and cetirizine by 80.1%. Intraperitoneal administration of drugs did not change painful behavior. When used in peripheral nerve block, in phase I pyrilamine reduced the number of paw elevations by 96.7%, promethazine by 73.3%, and cetirizine by 23.9%. In phase II, pyrilamine reduced the number of paw elevations by 86.6%, promethazine by 64.4%, and cetirizine by 19.9%. CONCLUSIONS: The results demonstrate that H1 receptor antagonists have local analgesic effects, different from the systemic effects, one of them an anti-inflammatory and class-specific effect and the other similarly to the local anesthetic effect, specific for promethazine and pyrilamine

  6. Synergism between dexketoprofen and meloxicam in an orofacial formalin test was not modified by opioid antagonists.

    Science.gov (United States)

    Gonzalez, Claudia; Zegpi, Carlos; Noriega, Viviana; Prieto, Juan C; Miranda, Hugo F

    2011-01-01

    Non-steroidal anti-inflammatory drugs (NSAIDs) are among the most widely used drugs for the management of acute and chronic pain. The role of the opioid system in the synergism between NSAIDs is not well characterized. Mice were injected with a 5% formalin solution (20 μl) into the upper right lip to perform an orofacial formalin test. The isobolographic method was used to determine the interaction between dexketoprofen, which is the (S)-(+) enantiomer of ketoprofen, and meloxicam co-administration. Additionally, the non-selective, opioid antagonist naltrexone, the selective δ opioid receptor (DOP) antagonist naltrindole and the selective κ opioid receptor (KOP) antagonist norbinaltorphimine were used to assess the opioid effects on this interaction. Intraperitoneal administration of dexketoprofen or meloxicam induced dose-dependent antinociception with different phase I and phase II potencies in the orofacial formalin test. Meloxicam displayed similar potencies (ED(50)) in phase I (7.20 mg/kg) and phase II (8.60 mg/kg). Dexketoprofen was more potent in phase I (19.96 mg/kg) than in phase II (50.90 mg/kg). The interactions between dexketoprofen and meloxicam were synergistic in both phases. This was determined based on the fixed ratios (1:1) of their ED(50) values, which were determined by isobolographic analysis. Furthermore, this antinociceptive activity does not seem to be modulated by opioid receptor blockers because they did not induce changes in the nature of this interaction. This finding may be relevant with regards to NSAID multi-modal analgesia where an opioid antagonist must be used.

  7. Internal image anti-idiotypic antibody: A new strategy for the development a new category of prolactin receptor (PRLR) antagonist.

    Science.gov (United States)

    Lan, Hainan; Hong, Pan; Li, Ruonan; L, Suo; Anshan, Shan; Li, Steven; Zheng, Xin

    2017-07-01

    Over the past decades, a number of prolactin receptor (PRLR) antagonists have been developed, which can be divided into two categories, PRLR analogue and anti-PRLR antibody. However, until now, there have been no commercially available PRLR antagonists. Here, we described a new approach for the preparation of PRLR antagonist, namely internal image anti-idiotypic antibody strategy. The hybridoma technique was used to generate anti-idiotypic antibodies to PRL. Competitive ELISA, competitive receptor-binding analysis and immunofluorescence assay (IFA) were then used to screen and characterize anti-idiotypic antibodies to PRL. One internal image anti-idiotypic antibody, termed MG7, was obtained. A series of experiments demonstrated that MG7 behaved as a typical internal image anti-idiotypic antibody (Ab2β). MG7 exhibited effective antagonistic activity, which not only inhibited PRL binding to PRLR in a dose-dependent manner but also inhibited PRLR-mediated intracellular signalling. Furthermore, MG7 also blocked Nb2 cell proliferation induced by PRL. The current study suggests that MG7 has the potential application in the PRL/PRLR-related studies in future. In addition, this work also suggests that the internal image anti-idiotypic antibody may represent a novel strategy for the development of PRLR antagonist. Copyright © 2017 Elsevier Ltd. All rights reserved.

  8. Receptor residence time trumps drug-likeness and oral bioavailability in determining efficacy of complement C5a antagonists

    Science.gov (United States)

    Seow, Vernon; Lim, Junxian; Cotterell, Adam J.; Yau, Mei-Kwan; Xu, Weijun; Lohman, Rink-Jan; Kok, W. Mei; Stoermer, Martin J.; Sweet, Matthew J.; Reid, Robert C.; Suen, Jacky Y.; Fairlie, David P.

    2016-04-01

    Drug discovery and translation are normally based on optimizing efficacy by increasing receptor affinity, functional potency, drug-likeness (rule-of-five compliance) and oral bioavailability. Here we demonstrate that residence time of a compound on its receptor has an overriding influence on efficacy, exemplified for antagonists of inflammatory protein complement C5a that activates immune cells and promotes disease. Three equipotent antagonists (3D53, W54011, JJ47) of inflammatory responses to C5a (3nM) were compared for drug-likeness, receptor affinity and antagonist potency in human macrophages, and anti-inflammatory efficacy in rats. Only the least drug-like antagonist (3D53) maintained potency in cells against higher C5a concentrations and had a much longer duration of action (t1/2 ~ 20 h) than W54011 or JJ47 (t1/2 ~ 1-3 h) in inhibiting macrophage responses. The unusually long residence time of 3D53 on its receptor was mechanistically probed by molecular dynamics simulations, which revealed long-lasting interactions that trap the antagonist within the receptor. Despite negligible oral bioavailability, 3D53 was much more orally efficacious than W54011 or JJ47 in preventing repeated agonist insults to induce rat paw oedema over 24 h. Thus, residence time on a receptor can trump drug-likeness in determining efficacy, even oral efficacy, of pharmacological agents.

  9. Receptor residence time trumps drug-likeness and oral bioavailability in determining efficacy of complement C5a antagonists

    Science.gov (United States)

    Seow, Vernon; Lim, Junxian; Cotterell, Adam J.; Yau, Mei-Kwan; Xu, Weijun; Lohman, Rink-Jan; Kok, W. Mei; Stoermer, Martin J.; Sweet, Matthew J.; Reid, Robert C.; Suen, Jacky Y.; Fairlie, David P.

    2016-01-01

    Drug discovery and translation are normally based on optimizing efficacy by increasing receptor affinity, functional potency, drug-likeness (rule-of-five compliance) and oral bioavailability. Here we demonstrate that residence time of a compound on its receptor has an overriding influence on efficacy, exemplified for antagonists of inflammatory protein complement C5a that activates immune cells and promotes disease. Three equipotent antagonists (3D53, W54011, JJ47) of inflammatory responses to C5a (3nM) were compared for drug-likeness, receptor affinity and antagonist potency in human macrophages, and anti-inflammatory efficacy in rats. Only the least drug-like antagonist (3D53) maintained potency in cells against higher C5a concentrations and had a much longer duration of action (t1/2 ~ 20 h) than W54011 or JJ47 (t1/2 ~ 1–3 h) in inhibiting macrophage responses. The unusually long residence time of 3D53 on its receptor was mechanistically probed by molecular dynamics simulations, which revealed long-lasting interactions that trap the antagonist within the receptor. Despite negligible oral bioavailability, 3D53 was much more orally efficacious than W54011 or JJ47 in preventing repeated agonist insults to induce rat paw oedema over 24 h. Thus, residence time on a receptor can trump drug-likeness in determining efficacy, even oral efficacy, of pharmacological agents. PMID:27094554

  10. Current position of 5HT3 antagonists and the additional value of NK1 antagonists; a new class of antiemetics

    NARCIS (Netherlands)

    R. de Wit (Ronald)

    2003-01-01

    textabstractThe advent of the 5HT3 receptor antagonists (5HT3 antagonists) in the 1990s and the combination with dexamethasone has resulted in acute emesis protection in 70% of patients receiving highly emetogenic chemotherapy. Despite complete protection in the acute phase, however, 40% of patients

  11. Effect of platelet activating factor antagonist treatment on gentamicin nephrotoxicity

    Directory of Open Access Journals (Sweden)

    A. Rodriguez-Barbero

    1992-01-01

    Full Text Available To assess whether PAF could be involved in the gentamicin-induced nephrotoxicity, we have studied the effect of PAF antagonist BN-52021 on renal function in rats after gentamicin (GENTA treatment. Experiments were completed in 21 Wistar rats divided into three groups: group GENTA was injected with gentamicin 100 mg kg−1 body wt/day s.c. for 6 days. Group GENTA + BN received gentamicin and BN-52021 i.p. 5 mg kg−1 body wt/day. A third group served as control. Rats were placed in meta-bolic cages and plasma creatinine and creatinine clearance were measured daily. GENTA group showed a progressive increase in plasma creatinine, a drop in creatinine clearance and an increase in urinary excretion of N-acetyl-β-D-glucosaminidase and alkaline phosphatase. GENTA + BN group showed a lesser change in plasma creatinine and a creatinine clearance, but no difference with GENTA group in urinary excretion of NAG and AP were observed. Histological examination revealed a massive cortical tubular necrosis in rats treated with gentamicin, whereas in BN-52021 injected animals tubular damage was markedly attenuated. The present results suggest a role for PAF in the gentamicininduced nephro-toxicity.

  12. Discovery and Characterization of an Endogenous CXCR4 Antagonist

    Directory of Open Access Journals (Sweden)

    Onofrio Zirafi

    2015-05-01

    Full Text Available CXCL12-CXCR4 signaling controls multiple physiological processes and its dysregulation is associated with cancers and inflammatory diseases. To discover as-yet-unknown endogenous ligands of CXCR4, we screened a blood-derived peptide library for inhibitors of CXCR4-tropic HIV-1 strains. This approach identified a 16 amino acid fragment of serum albumin as an effective and highly specific CXCR4 antagonist. The endogenous peptide, termed EPI-X4, is evolutionarily conserved and generated from the highly abundant albumin precursor by pH-regulated proteases. EPI-X4 forms an unusual lasso-like structure and antagonizes CXCL12-induced tumor cell migration, mobilizes stem cells, and suppresses inflammatory responses in mice. Furthermore, the peptide is abundant in the urine of patients with inflammatory kidney diseases and may serve as a biomarker. Our results identify EPI-X4 as a key regulator of CXCR4 signaling and introduce proteolysis of an abundant precursor protein as an alternative concept for chemokine receptor regulation.

  13. Chitinolytic Enterobacter agglomerans Antagonistic to Fungal Plant Pathogens.

    Science.gov (United States)

    Chernin, L; Ismailov, Z; Haran, S; Chet, I

    1995-05-01

    Three Enterobacter agglomerans strains which produce and excrete proteins with chitinolytic activity were found while screening soil-borne bacteria antagonistic to fungal plant pathogens. The chitinolytic activity was induced when the strains were grown in the presence of colloidal chitin as the sole carbon source. It was quantitated by using assays with chromogenic p-nitrophenyl analogs of disaccharide, trisaccharide, and tetrasaccharide derivatives of N-acetylglucosamine. A set of three fluorescent substrates with a 4-methylumbelliferyl group linked by (beta)-1,4 linkage to N-acetylglucosamine mono- or oligosaccharides were used to identify the chitinolytic activities of proteins which had been renatured following their separation by electrophoresis. This study provides the most complete evidence for the presence of a complex of chitinolytic enzymes in Enterobacter strains. Four enzymes were detected: two N-acetyl-(beta)-d-glucosaminidases of 89 and 67 kDa, an endochitinase with an apparent molecular mass of 59 kDa, and a chitobiosidase of 50 kDa. The biocontrol ability of the chitinolytic strains was demonstrated under greenhouse conditions. The bacteria decreased the incidence of disease caused by Rhizoctonia solani in cotton by 64 to 86%. Two Tn5 mutants of one of the isolates, which were deficient in chitinolytic activity, were unable to protect plants against the disease.

  14. A new class of NO-donor H3-antagonists.

    Science.gov (United States)

    Tosco, Paolo; Bertinaria, Massimo; Di Stilo, Antonella; Marini, Elisabetta; Rolando, Barbara; Sorba, Giovanni; Fruttero, Roberta; Gasco, Alberto

    2004-05-01

    Synthesis and pharmacological characterisation of a series of compounds obtained by joining, through appropriate spacers, NO-donor furoxan and nitrooxy moieties to the imidazole ring, as well as their structurally related analogues devoid of NO-donating properties are described. All the products were studied for their capacity to interact with H3-receptors present on the guinea-pig ileum and with H2-receptors present on guinea-pig right atrium. The whole series of products displayed reversible H3-antagonistic activity. No activity on H2-receptors was observed when the products were tested at 10 microM concentration. Many of the products were also able to induce partial relaxation when added to the bath after electrical contraction of the guinea-pig ileum during the study of their H3-antagonism. This phenomenon seems to be dependent on various factors; for some compounds it proved to be dependent on NO-mediated sGC activation, for other products it could be due to their weak M3-antagonism. The investigation of the lipophilic-hydrophilic balance of all the products indicates, for many of them, an ideal value to cross the blood-brain barrier. Copyright 2004 Elsevier SAS

  15. The Hypocretin/Orexin Antagonist Almorexant Promotes Sleep Without Impairment of Performance in Rats

    Directory of Open Access Journals (Sweden)

    Stephen R Morairty

    2014-01-01

    Full Text Available The hypocretin receptor (HcrtR antagonist almorexant (ALM has potent hypnotic actions but little is known about neurocognitive performance in the presence of ALM. HcrtR antagonists are hypothesized to induce sleep by disfacilitation of wake-promoting systems whereas GABAA receptor modulators such as zolpidem (ZOL induce sleep through general inhibition of neural activity. To test the hypothesis that less functional impairment results from HcrtR antagonist-induced sleep, we evaluated the performance of rats in the Morris Water Maze in the presence of ALM vs. ZOL. Performance in spatial reference memory (SRM and spatial working memory (SWM tasks were assessed during the dark period after equipotent sleep-promoting doses (100 mg/kg, po following undisturbed and sleep deprivation (SD conditions. ALM-treated rats were indistinguishable from vehicle (VEH-treated rats for all SRM performance measures (distance travelled, latency to enter, time within, and number of entries into, the target quadrant after both the undisturbed and 6 h SD conditions. In contrast, rats administered ZOL showed impairments in all parameters measured compared to VEH or ALM in the undisturbed conditions. Following SD, ZOL-treated rats also showed impairments in all measures. ALM-treated rats were similar to VEH-treated rats for all SWM measures (velocity, time to locate the platform and success rate at finding the platform within 60 s after both the undisturbed and SD conditions. In contrast, ZOL-treated rats showed impairments in velocity and in the time to locate the platform. Importantly, ZOL rats only completed the task 23-50% of the time while ALM and VEH rats completed the task 79-100% of the time. Thus, following equipotent sleep-promoting doses, ZOL impaired rats in both memory tasks while ALM rats performed at levels comparable to VEH rats. These results are consistent with the hypothesis that less impairment results from HcrtR antagonism than from GABAA-induced

  16. New trends in combined use of gonadotropin-releasing hormone antagonists with gonadotropins or pulsatile gonadotropin-releasing hormone in ovulation induction and assisted reproductive technologies.

    Science.gov (United States)

    Gordon, K; Danforth, D R; Williams, R F; Hodgen, G D

    1992-10-01

    The use of gonadotropin-releasing hormone agonists as adjunctive therapy with gonadotropins for ovulation induction in in vitro fertilization and other assisted reproductive technologies has become common clinical practice. With the recent advent of potent gonadotropin-releasing hormone antagonists free from the marked histamine-release effects that stymied earlier compounds, an attractive alternative method may be available. We have established the feasibility of combining gonadotropin-releasing hormone antagonist-induced inhibition of endogenous gonadotropins with exogenous gonadotropin therapy for ovulation induction in a nonhuman primate model. Here, the principal benefits to be gained from using the gonadotropin-releasing hormone antagonist rather than the gonadotropin-releasing hormone agonist are the immediate inhibition of pituitary gonadotropin secretion without the "flare effect," which brings greater safety and convenience for patients and the medical team and saves time and money. We have also recently demonstrated the feasibility of combining gonadotropin-releasing hormone antagonist with pulsatile gonadotropin-releasing hormone therapy for the controlled restoration of gonadotropin secretion and gonadal steroidogenesis culminating in apparently normal (singleton) ovulatory cycles. This is feasible only with gonadotropin-releasing hormone antagonists because, unlike gonadotropin-releasing hormone agonists, they achieve control of the pituitary-ovarian axis without down regulation of the gonadotropin-releasing hormone receptor system. This capacity to override gonadotropin-releasing hormone antagonist-induced suppression of pituitary-ovarian function may allow new treatment modalities to be employed for women who suffer from chronic hyperandrogenemia with polycystic ovarian disease.

  17. Favorable prognostic value of SOCS2 and IGF-I in breast cancer

    Directory of Open Access Journals (Sweden)

    Daxenbichler Günter

    2007-07-01

    Full Text Available Abstract Background Suppressor of cytokine signaling (SOCS proteins comprise a protein family, which has initially been described as STAT induced inhibitors of the Jak/Stat pathway. Recent in vivo and in vitro studies suggest that SOCS proteins are also implicated in cancer. The STAT5 induced IGF-I acts as an endocrine and para/autocrine growth and differentiation factor in mammary gland development. Whereas high levels of circulating IGF-I have been associated with increased cancer risk, the role of autocrine acting IGF-I is less clear. The present study is aimed to elucidate the clinicopathological features associated with SOCS1, SOCS2, SOCS3, CIS and IGF-I expression in breast cancer. Methods We determined the mRNA expression levels of SOCS1, SOCS2, SOCS3, CIS and IGF-I in 89 primary breast cancers by reverse transcriptase PCR. SOCS2 protein expression was further evaluated by immuno-blot and immunohistochemistry. Results SOCS2 expression inversely correlated with histopathological grade and ER positive tumors exhibited higher SOCS2 levels. Patients with high SOCS2 expression lived significantly longer (108.7 vs. 77.7 months; P = 0.015 and high SOCS2 expression proved to be an independent predictor for good prognosis (HR = 0.45, 95% CI 0.23 – 0.91, P = 0.026. In analogy to SOCS2, high IGF-I expression was an independent predictor for good prognosis in the entire patient cohort. In the subgroup of patients with lymph-node negative disease, high IGF-I was a strong predictor for favorable outcome in terms of overall survival and relapse free survival (HR = 0.075, 95% CI 0.014 – 0.388, P = 0.002. Conclusion This is the first report on the favorable prognostic value of high SOCS2 expression in primary mammary carcinomas. Furthermore a strong association of high IGF-I expression levels with good prognosis was observed especially in lymph-node negative patients. Our results suggest that high expression of the STAT5 target genes SOCS2 and IGF

  18. Antagonistic Effects of Sodium Butyrate and N-(4-Hydroxyphenyl-retinamide on Prostate Cancer

    Directory of Open Access Journals (Sweden)

    Rainer Kuefer

    2007-03-01

    Full Text Available Butyrates and retinoids are promising antineoplastic agents. Here we analyzed effects of sodium butyrate and N-(4-hydroxyphenyl-retinamide (4-HPR on prostate cancer cells as monotherapy or in combination in vitro and in vivo. Sodium butyrate and 4-HPR induced concentration-dependent growth inhibition in prostate cancer cells in vitro. The isobologram analysis revealed that sodium butyrate and 4-HPR administered together antagonize effects of each other. For the in vivo studies, a water-soluble complex (4-HPR with a cyclodextrin was created. A single dose of sodium butyrate and 4-HPR showed a peak level in chicken plasma within 30 minutes. Both compounds induced inhibition of proliferation and apoptosis in xenografts of the chicken chorioallantoic membrane. Analysis of the cytotoxic effects of the drugs used in combination demonstrated an antagonistic effect on inhibition of proliferation and on induction of apoptosis. Prolonged jun N-terminal kinase phosphorylation induced by sodium butyrate and 4-HPR was strongly attenuated when both compounds were used in combination. Both compounds induced inhibition of NF-κ,B. This effect was strongly antagonized in LNCaP cells when the compounds were used in combination. These results indicate that combinational therapies have to be carefully investigated due to potential antagonistic effects in the clinical setting despite promising results of a monotherapy.

  19. The Role of Interferon Antagonist, Non-Structural Proteins in the Pathogenesis and Emergence of Arboviruses

    Directory of Open Access Journals (Sweden)

    Samantha S. Soldan

    2011-06-01

    Full Text Available A myriad of factors favor the emergence and re-emergence of arthropod-borne viruses (arboviruses, including migration, climate change, intensified livestock production, an increasing volume of international trade and transportation, and changes to ecosystems (e.g., deforestation and loss of biodiversity. Consequently, arboviruses are distributed worldwide and represent over 30% of all emerging infectious diseases identified in the past decade. Although some arboviral infections go undetected or are associated with mild, flu-like symptoms, many are important human and veterinary pathogens causing serious illnesses such as arthritis, gastroenteritis, encephalitis and hemorrhagic fever and devastating economic loss as a consequence of lost productivity and high mortality rates among livestock. One of the most consistent molecular features of emerging arboviruses, in addition to their near exclusive use of RNA genomes, is the inclusion of viral, non-structural proteins that act as interferon antagonists. In this review, we describe these interferon antagonists and common strategies that arboviruses use to counter the host innate immune response. In addition, we discuss the complex interplay between host factors and viral determinants that are associated with virus emergence and re-emergence, and identify potential targets for vaccine and anti-viral therapies.

  20. Antagonistic neural networks underlying differentiated leadership roles

    Science.gov (United States)

    Boyatzis, Richard E.; Rochford, Kylie; Jack, Anthony I.

    2014-01-01

    The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950s. Recent research in neuroscience suggests that the division between task-oriented and socio-emotional-oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks – the task-positive network (TPN) and the default mode network (DMN). Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task-oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions, and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success. PMID:24624074

  1. Antagonistic Neural Networks Underlying Differentiated Leadership Roles

    Directory of Open Access Journals (Sweden)

    Richard Eleftherios Boyatzis

    2014-03-01

    Full Text Available The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950’s. Recent research in neuroscience suggests that the division between task oriented and socio-emotional oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks -- the Task Positive Network (TPN and the Default Mode Network (DMN. Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success.

  2. Antagonistic neural networks underlying differentiated leadership roles.

    Science.gov (United States)

    Boyatzis, Richard E; Rochford, Kylie; Jack, Anthony I

    2014-01-01

    The emergence of two distinct leadership roles, the task leader and the socio-emotional leader, has been documented in the leadership literature since the 1950s. Recent research in neuroscience suggests that the division between task-oriented and socio-emotional-oriented roles derives from a fundamental feature of our neurobiology: an antagonistic relationship between two large-scale cortical networks - the task-positive network (TPN) and the default mode network (DMN). Neural activity in TPN tends to inhibit activity in the DMN, and vice versa. The TPN is important for problem solving, focusing of attention, making decisions, and control of action. The DMN plays a central role in emotional self-awareness, social cognition, and ethical decision making. It is also strongly linked to creativity and openness to new ideas. Because activation of the TPN tends to suppress activity in the DMN, an over-emphasis on task-oriented leadership may prove deleterious to social and emotional aspects of leadership. Similarly, an overemphasis on the DMN would result in difficulty focusing attention, making decisions, and solving known problems. In this paper, we will review major streams of theory and research on leadership roles in the context of recent findings from neuroscience and psychology. We conclude by suggesting that emerging research challenges the assumption that role differentiation is both natural and necessary, in particular when openness to new ideas, people, emotions, and ethical concerns are important to success.

  3. Multiple Targeting Approaches on Histamine H3 Receptor Antagonists

    Directory of Open Access Journals (Sweden)

    Mohammad eKhanfar

    2016-05-01

    Full Text Available With the very recent market approval of pitolisant (Wakix®, the interest in clinical applications of novel multifunctional histamine H3 receptor antagonists has clearly increased. Since histamine H3 receptor antagonists in clinical development have been tested for a variety of different indications, the combination of pharmacological properties in one molecule for improved pharmacological effects and reduced unwanted side-effects is rationally based on the increasing knowledge on the complex neurotransmitter regulations. The polypharmacological approaches on histamine H3 receptor antagonists on different G-protein coupled receptors, transporters, enzymes as well as on NO-signaling mechanism are described, supported with some lead structures.

  4. Possible site of action of CGRP antagonists in migraine

    DEFF Research Database (Denmark)

    Tfelt-Hansen, Peer; Olesen, Jes

    2011-01-01

    The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. Both are effective in migraine but in doses much higher than would be predicted from receptor binding and other in vitro results. This could perhaps suggest an effect of CGRP antagoni......The calcitonin gene-related peptide (CGRP) receptor antagonists olcegepant and telcagepant are very potent drugs. Both are effective in migraine but in doses much higher than would be predicted from receptor binding and other in vitro results. This could perhaps suggest an effect of CGRP...... antagonists behind the blood-brain barrier (BBB), i.e. in the central nervous system (CNS)....

  5. Accelerated habit formation following amphetamine exposure is reversed by D1, but enhanced by D2, receptor antagonists

    Directory of Open Access Journals (Sweden)

    Andrew John Dudley Nelson

    2013-05-01

    Full Text Available Repeated exposure to the psychostimulant amphetamine has been shown to disrupt goal-directed instrumental actions and promote the early and abnormal development of goal-insensitive habitual responding (Nelson and Killcross, 2006. To investigate the neuropharmacological specificity of this effect as well as restore goal-directed responding in animals with pre-training amphetamine exposure, animals were treated with the non-selective dopamine antagonist α-flupenthixol, the selective D1 antagonist SCH 23390 or the selective D2 antagonist eticlopride, prior to instrumental training (3 sessions. Subsequently, the reinforcer was paired with LiCL-induced gastric-malaise and animals were given a test of goal-sensitivity both in extinction and reacquisition. The effect of these dopaminergic antagonists on the sensitivity of lever press performance to outcome devaluation was assessed in animals with pre-training exposure to amphetamine (Experiments 1a-1c or in non-sensitized animals (Experiment 2. Both α-flupenthixol and SCH23390 reversed accelerated habit formation following amphetamine sensitization. However, eticlopride appeared to enhance this effect and render instrumental performance compulsive as these animals were unable to inhibit responding both in extinction and reacquisition, even though a consumption test confirmed they had acquired an aversion to the reinforcer. These findings demonstrate that amphetamine induced-disruption of goal-directed behaviour is mediated by activity at distinct dopamine receptor subtypes and may represent a putative model of the neurochemical processes involved in the loss of voluntary control over behaviour.

  6. Identification of a New Morpholine Scaffold as a P2Y12 Receptor Antagonist

    Directory of Open Access Journals (Sweden)

    Young Ha Ahn

    2016-08-01

    Full Text Available The P2Y12 receptor is critical for platelet activation and is an attractive drug target for the prevention of atherothrombotic events. Despite the proven antithrombotic efficacy of P2Y12 inhibitors, these thienopyridine scaffolds are prodrugs that lack important features of the ideal antithrombotic agent. For this reason, ticagrelor—a new chemical class of P2Y12 receptor antagonist—was developed, but it can cause shortness of breath and various types of bleeding. Moreover, ticagrelor is a cytochrome P450 3A4 substrate/inhibitor and, therefore, caution should be exercised when it is used concomitantly with strong CYP3A4 inducers/inhibitors. There is a need for novel P2Y12 receptor antagonist scaffolds that are reversible and have high efficacy without associated side effects. Here, we describe a novel antagonist containing a morpholine moiety that was identified by screening libraries of commercially available compounds. The molecule, Compound E, acted on P2Y12, but not P2Y1 and P2Y13, and exhibited pharmacological characteristics that were distinct from those of ticagrelor, acting instead on P2Y12 via an allosteric mechanism. These results provide a basis for the development/optimization of a new class of P2Y12 antagonists.

  7. An α4β1 integrin antagonist decreases airway inflammation in ovalbumin-exposed mice

    Science.gov (United States)

    Kenyon, Nicholas J.; Liu, Ruiwu; O’Roark, Erin M.; Huang, Wenzhe; Peng, Li; Lam, Kit S.

    2008-01-01

    Inhibition of the α4 subunit of both the α4β1 and α4β7 integrins has shown promise in decreasing airway inflammation and airway hyperresponsiveness in various animal models. We hypothesized that a novel, high-affinity α4β1 antagonist (LLP2A) would decrease the migration of eosinophils to the lung and ameliorate the airway hyperresponsiveness in a mouse model of ovalbumin-induced airway inflammation. To test this hypothesis, we administered LLP2A, or scrambled LLP2A (a negative control), prior to exposure of sensitized BALB/c mice to ovalbumin aerosol. We can partially prevent, or reverse, the airway inflammatory response, but not airways hyperresponsiveness, by treatment of mice with LLP2A, a synthetic peptidomimetic α4β1 antagonist LLP2A. Specifically engineered, PEGylated (PEG) formulations of this antagonist further reduce the airway inflammatory response to ovalbumin lbumin, presumably by improving the circulating half-life of the drug. PMID:19103195

  8. Cabibbo-Kobayashi-Maskawa-favored B decays to a scalar meson and a D meson

    Energy Technology Data Exchange (ETDEWEB)

    Zou, Zhi-Tian; Li, Ying [Yantai University, Department of Physics, Yantai (China); Liu, Xin [Jiangsu Normal University, School of Physics and Electronic Engineering, Xuzhou (China)

    2017-12-15

    In this work, we attempt to study the Cabibbo-Kobayashi-Maskawa-favored B → anti DS (''S'' denoting the scalar meson) decays within the perturbative QCD approach at the leading order and the leading power. Although the light scalar mesons are widely perceived as primarily the four-quark bound states, in practice it is hard for us to make quantitative predictions based on the four-quark picture for light scalars. Hence, we calculate the decays with light scalars in the two-quark model. For the decays with scalar mesons above 1 GeV, we have explored two possible scenarios, depending on whether the light scalars are treated as the lowest lying q anti q states or four-quark particles. In total, we calculated the branching fractions of 72 decay modes, and most of them are in the range 10{sup -4}-10{sup -7}, which are measurable in the on-going LHCb experiment and the forthcoming Belle-II experiment. Moreover, since in the standard model these decays occur only through tree operators and have no CP asymmetries, any deviation will be a signal of new physics beyond the standard model. Despite large uncertainties induced by nonperturbative parameters and corrections of high order and high power, our results and discussions will be useful for the on-going LHCb and the forthcoming Belle-II experiments. (orig.)

  9. The cohesion stabilizer sororin favors DNA repair and chromosome segregation during mouse oocyte meiosis.

    Science.gov (United States)

    Huang, Chun-Jie; Yuan, Yi-Feng; Wu, Di; Khan, Faheem Ahmed; Jiao, Xiao-Fei; Huo, Li-Jun

    2017-03-01

    Maintenance and timely termination of cohesion on chromosomes ensures accurate chromosome segregation to guard against aneuploidy in mammalian oocytes and subsequent chromosomally abnormal pregnancies. Sororin, a cohesion stabilizer whose relevance in antagonizing the anti-cohesive property of Wings-apart like protein (Wapl), has been characterized in mitosis; however, the role of Sororin remains unclear during mammalian oocyte meiosis. Here, we show that Sororin is required for DNA damage repair and cohesion maintenance on chromosomes, and consequently, for mouse oocyte meiotic program. Sororin is constantly expressed throughout meiosis and accumulates on chromatins at germinal vesicle (GV) stage/G2 phase. It localizes onto centromeres from germinal vesicle breakdown (GVBD) to metaphase II stage. Inactivation of Sororin compromises the GVBD and first polar body extrusion (PBE). Furthermore, Sororin inactivation induces DNA damage indicated by positive γH2AX foci in GV oocytes and precocious chromatin segregation in MII oocytes. Finally, our data indicate that PlK1 and MPF dissociate Sororin from chromosome arms without affecting its centromeric localization. Our results define Sororin as a determinant during mouse oocyte meiotic maturation by favoring DNA damage repair and chromosome separation, and thereby, maintaining the genome stability and generating haploid gametes.

  10. The interleukin (IL)-1 cytokine family--Balance between agonists and antagonists in inflammatory diseases.

    Science.gov (United States)

    Palomo, Jennifer; Dietrich, Damien; Martin, Praxedis; Palmer, Gaby; Gabay, Cem

    2015-11-01

    The interleukin (IL)-1 family of cytokines comprises 11 members, including 7 pro-inflammatory agonists (IL-1α, IL-1β, IL-18, IL-33, IL-36α, IL-36β, IL-36γ) and 4 defined or putative antagonists (IL-1R antagonist (IL-1Ra), IL-36Ra, IL-37, and IL-38) exerting anti-inflammatory activities. Except for IL-1Ra, IL-1 cytokines do not possess a leader sequence and are secreted via an unconventional pathway. In addition, IL-1β and IL-18 are produced as biologically inert pro-peptides that require cleavage by caspase-1 in their N-terminal region to generate active proteins. N-terminal processing is also required for full activity of IL-36 cytokines. The IL-1 receptor (IL-1R) family comprises 10 members and includes cytokine-specific receptors, co-receptors and inhibitory receptors. The signaling IL-1Rs share a common structure with three extracellular immunoglobulin (Ig) domains and an intracellular Toll-like/IL-1R (TIR) domain. IL-1 cytokines bind to their specific receptor, which leads to the recruitment of a co-receptor and intracellular signaling. IL-1 cytokines induce potent inflammatory responses and their activity is tightly controlled at the level of production, protein processing and maturation, receptor binding and post-receptor signaling by naturally occurring inhibitors. Some of these inhibitors are IL-1 family antagonists, while others are IL-1R family members acting as membrane-bound or soluble decoy receptors. An imbalance between agonist and antagonist levels can lead to exaggerated inflammatory responses. Several genetic modifications or mutations associated with dysregulated IL-1 activity and autoinflammatory disorders were identified in mouse models and in patients. These findings paved the road to the successful use of IL-1 inhibitors in diseases that were previously considered as untreatable. Copyright © 2015 Elsevier Ltd. All rights reserved.

  11. Don't stress about CRF: assessing the translational failures of CRF1antagonists.

    Science.gov (United States)

    Spierling, Samantha R; Zorrilla, Eric P

    2017-05-01

    Dr. Athina Markou sought treatments for a common neural substrate shared by depression and drug dependence. Antagonists of corticotropin-releasing factor (CRF) receptors, a target of interest to her, have not reached the clinic despite strong preclinical rationale and sustained translational efforts. We explore potential causes for the failure of CRF 1 antagonists and review recent findings concerning CRF-CRF 1 systems in psychopathology. Potential causes for negative outcomes include (1) poor safety and efficacy of initial drug candidates due to bad pharmacokinetic and physicochemical properties, (2) specificity problems with preclinical screens, (3) the acute nature of screens vs. late-presenting patients, (4) positive preclinical results limited to certain models and conditions with dynamic CRF-CRF 1 activation not homologous to tested patients, (5) repeated CRF 1 activation-induced plasticity that reduces the importance of ongoing CRF 1 agonist stimulation, and (6) therapeutic silencing which may need to address CRF 2 receptor or CRF-binding protein molecules, constitutive CRF 1 activity, or molecules that influence agonist-independent activity or to target structural regions other than the allosteric site bound by all drug candidates. We describe potential markers of activation towards individualized treatment, human genetic, and functional data that still implicate CRF 1 systems in emotional disturbance, sex differences, and suggestive clinical findings for CRF 1 antagonists in food craving and CRF-driven HPA-axis overactivation. The therapeutic scope of selective CRF 1 antagonists now appears narrower than had been hoped. Yet, much remains to be learned about CRF's role in the neurobiology of dysphoria and addiction and the potential for novel anti-CRF therapies therein.

  12. Effect of NMDA NR2B antagonist on neuropathic pain in two spinal cord injury models.

    Science.gov (United States)

    Kim, Youngkyung; Cho, Hwi-young; Ahn, Young Ju; Kim, Junesun; Yoon, Young Wook

    2012-05-01

    N-Methyl-d-aspartate (NMDA) receptors are thought to play an important role in the processes of central sensitization and pathogenesis of neuropathic pain, particularly after spinal cord injury (SCI). NMDA antagonists effectively reduce neuropathic pain, but serious side effects prevent their use as therapeutic drugs. NMDA NR2B antagonists have been reported to effectively reduce inflammatory and neuropathic pain. In this study, we investigated the effects of NR2B antagonists on neuropathic pain and the expression of NR2B in the spinal cord in 2 SCI models. SCI was induced at T12 by a New York University impactor (contusion) or by sectioning of the lateral half of the spinal cord (hemisection). Ifenprodil (100, 200, 500, 1000nmol) and Ro25-6981 (20, 50, 100, 200nmol) were intrathecally injected and behavioral tests were conducted. Ifenprodil increased the paw withdrawal threshold in both models but also produced mild motor depression at higher doses. Ro25-6981 increased the mechanical nociceptive threshold in a dose-dependent manner without motor depression. NR2B expression was significantly increased on both sides at the spinal segments of L1-2 and L4-5 in the hemisection model but did not change in the contusion model. Increased expression of NR2B in the hemisection model was reduced by intrathecal ifenprodil. These results suggest that intrathecal NMDA NR2B antagonist increased the mechanical nociceptive threshold after SCI without motor depression. A selective subtype of NMDA receptor, such as NR2B, may be a more selective target for pain control because NMDA receptors play a crucial role in the development and maintenance of chronic pain. Copyright © 2012 International Association for the Study of Pain. Published by Elsevier B.V. All rights reserved.

  13. Practical recommendations for calcium channel antagonist poisoning.

    Science.gov (United States)

    Rietjens, S J; de Lange, D W; Donker, D W; Meulenbelt, J

    2016-02-01

    Calcium channel antagonists (CCAs) are widely used for different cardiovascular disorders. At therapeutic doses, CCAs have a favourable side effect profile. However, in overdose, CCAs can cause serious complications, such as severe hypotension and bradycardia. Patients in whom a moderate to severe intoxication is anticipated should be observed in a monitored setting for at least 12 hours if an immediate-release formulation is ingested, and at least 24 hours when a sustained-release formulation (or amlodipine) is involved, even if the patient is asymptomatic. Initial treatment is aimed at gastrointestinal decontamination and general supportive care, i.e., fluid resuscitation and correction of metabolic acidosis and electrolyte disturbances. In moderate to severe CCA poisoning, a combined medical strategy might be indispensable, such as administration of vasopressors, intravenous calcium and hyperinsulinaemia/euglycaemia therapy. Especially hyperinsulinaemia/euglycaemia therapy is an important first-line treatment in CCA-overdosed patients in whom a large ingestion is suspected. High-dose insulin, in combination with glucose, seems to be most effective when used early in the intoxication phase, even when the patient shows hardly any haemodynamic instability. Intravenous lipid emulsion therapy should only be considered in patients with life-threatening cardiovascular toxicity, such as refractory shock, which is unresponsive to conventional therapies. When supportive and specific pharmacological measures fail to adequately reverse refractory conditions in CCA overdose, the use of extracorporeal life support should be considered. The efficacy of these pharmacological and non-pharmacological interventions generally advocated in CCA poisoning needs further in-depth mechanistic foundation, in order to improve individualised treatment of CCA-overdosed patients.

  14. Neuroprotection afforded by antagonists of endothelin-1 receptors in experimental stroke.

    Science.gov (United States)

    Moldes, Octavio; Sobrino, Tomás; Blanco, Miguel; Agulla, Jesús; Barral, David; Ramos-Cabrer, Pedro; Castillo, José

    2012-12-01

    Endothelin-1 (ET-1) is involved on the development of cerebral edema in acute ischemic stroke. As edema is a therapeutic target in cerebral ischemia, our aim was to study the effect of antagonists for ET-1 receptors (Clazosentan® and BQ-788, specific antagonists for receptors A and B, respectively) on the development of edema, infarct volume and sensorial-motor deficits in rats subjected to ischemia by occlusion of the middle cerebral artery (MCAO). We used Wistar rats (280-320 g) submitted to ischemia by intraluminal transient (90 min) MCAO. After ischemia, rats were randomized into 4 groups (n = 6) treated with; 1) control group (saline), 2) Clazosentan® group (10 mg/kg iv), 3) BQ-788 group (3 mg/kg iv), and 4) combined treatment (Clazosentan® 10 mg/kg plus BQ-788 3 mg/kg iv). We observed that rats treated with Clazosentan® showed a reduction of edema, measured by MRI, at 72 h (hours) and at day 7 (both p < 0.0001), and a decrease in the serum levels of ET-1 at 72 h (p < 0.0001) and at day 7 (p = 0.009). The combined treatment also induced a reduction of edema at 24 h (p = 0.004), 72 h (p < 0.0001) and at day 7 (p < 0.0001), a reduction on infarct volume, measured by MRI, at 24 and 72 h, and at day 7 (all p < 0.01), and a better sensorimotor recovery at 24 and 72 h, and at day 7 (all p < 0.01). Moreover, Clazosentan® induced a decrease in AQP4 expression, while BQ-788 induced an increase in AQP9 expression. These results suggest that antagonists for ET-1 receptors may be a good therapeutic target for cerebral ischemia. Copyright © 2012 Elsevier Ltd. All rights reserved.

  15. Characterization and design of antagonistic shape memory alloy actuators

    International Nuclear Information System (INIS)

    Georges, T; Brailovski, V; Terriault, P

    2012-01-01

    Antagonistic shape memory actuators use opposing shape memory alloy (SMA) elements to create devices capable of producing differential motion paths and two-way mechanical work in a very efficient manner. There is no requirement for additional bias elements to ‘re-arm’ the actuators and allow repetitive actuation. The work generation potential of antagonistic shape memory actuators is determined by specific SMA element characteristics and their assembly conditions. In this study, the selected SMA wires are assembled in antagonistic configuration and characterized using a dedicated test bench to evaluate their stress–strain characteristics as a function of the number of cycles. Using these functional characteristics, a so-called ‘working envelope’ is built to assist in the design of such an actuator. Finally, the test bench is used to simulate a real application of an antagonistic actuator (case study). (paper)

  16. A SELECTIVE ANTAGONIST OF MINERALOCORTICOID RECEPTOR EPLERENONE IN CARDIOLOGY PRACTICE

    Directory of Open Access Journals (Sweden)

    B. B. Gegenava

    2015-01-01

    Full Text Available The role of aldosterone in pathophysiological processes is considered. The effects of the selective antagonist of mineralocorticoid receptor eplerenone are analyzed. The advantages of eplerenone compared with spironolactone are discussed.

  17. Development of KGF Antagonist as a Breast Cancer Therapeutic

    National Research Council Canada - National Science Library

    Sugimoto, Yasuro

    2003-01-01

    .... We were able to show some potential intracellular KGFR target small molecules whereas extracellular target synthetic peptide antagonist was not able to do during this period We also added a new...

  18. Recent Development of Non-Peptide GnRH Antagonists

    Directory of Open Access Journals (Sweden)

    Feng-Ling Tukun

    2017-12-01

    Full Text Available The decapeptide gonadotropin-releasing hormone, also referred to as luteinizing hormone-releasing hormone with the sequence (pGlu-His-Trp-Ser-Tyr-Gly-Leu-Arg-Pro-Gly-NH2 plays an important role in regulating the reproductive system. It stimulates differential release of the gonadotropins FSH and LH from pituitary tissue. To date, treatment of hormone-dependent diseases targeting the GnRH receptor, including peptide GnRH agonist and antagonists are now available on the market. The inherited issues associate with peptide agonists and antagonists have however, led to significant interest in developing orally active, small molecule, non-peptide antagonists. In this review, we will summarize all developed small molecule GnRH antagonists along with the most recent clinical data and therapeutic applications.

  19. Complications of TNF-α antagonists and iron homeostasis

    Science.gov (United States)

    TNF-α is a central regulator of inflammation and its blockade downregulates other proinflammatory cytokines, chemokines, and growth factors. Subsequently, TNF-α antagonists are currently used in treatment regimens directed toward several inflammatory diseases. Despite a beneficia...

  20. Pharmacological characterization of AZD5069, a slowly reversible CXC chemokine receptor 2 antagonist.

    Science.gov (United States)

    Nicholls, David J; Wiley, Katherine; Dainty, Ian; MacIntosh, Fraser; Phillips, Caroline; Gaw, Alasdair; Mårdh, Carina Kärrman

    2015-05-01

    In normal physiologic responses to injury and infection, inflammatory cells enter tissue and sites of inflammation through a chemotactic process regulated by several families of proteins, including inflammatory chemokines, a family of small inducible cytokines. In neutrophils, chemokines chemokine (CXC motif) ligand 1 (CXCL1) and CXCL8 are potent chemoattractants and activate G protein-coupled receptors CXC chemokine receptor 1 (CXCR1) and CXCR2. Several small-molecule antagonists of CXCR2 have been developed to inhibit the inflammatory responses mediated by this receptor. Here, we present the data describing the pharmacology of AZD5069 [N-(2-(2,3-difluorobenzylthio)-6-((2R,3S)-3,4-dihydroxybutan-2-yloxy)[2,4,5,6-(13)C4, 1,3-(15)N2]pyrimidin-4-yl)azetidine-1-sulfonamide,[(15)N2,(13)C4]N-(2-(2,3-difluoro-6-[3H]-benzylthio)-6-((2R,3S)-3,4-dihydroxybutan-2-yloxy)pyrimidin-4-yl)azetidine-1-sulfonamide], a novel antagonist of CXCR2. AZD5069 was shown to inhibit binding of radiolabeled CXCL8 to human CXCR2 with a pIC50 value of 9.1. Furthermore, AZD5069 inhibited neutrophil chemotaxis, with a pA2 of approximately 9.6, and adhesion molecule expression, with a pA2 of 6.9, in response to CXCL1. AZD5069 was a slowly reversible antagonist of CXCR2 with effects of time and temperature evident on the pharmacology and binding kinetics. With short incubation times, AZD5069 appeared to have an antagonist profile with insurmountable antagonism of calcium response curves. This behavior was also observed in vivo in an acute lipopolysaccharide-induced lung inflammation model. Altogether, the data presented here show that AZD5069 represents a novel, potent, and selective CXCR2 antagonist with potential as a therapeutic agent in inflammatory conditions. Copyright © 2015 by The American Society for Pharmacology and Experimental Therapeutics.

  1. Perioperative management of vitamin K antagonists in patients with low thromboembolic risk undergoing elective surgery: A prospective experience.

    Science.gov (United States)

    Becerra, Ana Florencia; Cornavaca, María Teresita; Revigliono, José Ignacio; Contreras, Alejandro; Albertini, Ricardo; Tabares, Aldo Hugo

    2017-10-11

    To quantify thromboembolic and bleeding events in patients with low thromboembolic risk, who were chronically receiving vitamin K antagonists and undergoing elective surgery. A descriptive, prospective, single-center study was conducted between December 2010 and July 2014. Patients aged over 18 years old, chronically anticoagulated with vitamin K antagonists and admitted for elective surgery were included in the study. We excluded patients with a creatinine clearance120kg, heparin-induced thrombocytopenia, pregnant women, carriers of an epidural catheter for analgesia, patients who underwent unscheduled surgery and high thromboembolic risk-patients. Vitamin K antagonists were discontinued 5 days prior to the procedure without administering anticoagulant enoxaparin. The NIR was measured 24h before the procedure. A single dose of 3mg of vitamin K was administered in cases of a NIR>1.5. Vitamin K antagonists was resumed according to the surgical bleeding risk. Events were registered between 5 days prior to the procedure until 30 days after it. A total of 75 procedures were included in the study. Fifty-six patients (74.7%) received vitamin K antagonists for atrial fibrillation, 15 suffered from venous thromboembolism (20%) and 4 had mechanical heart valves (5.3%). Twenty-six patients (34.5%) underwent high-bleeding risk surgeries and 49 (65.5%) underwent low risk procedures. No thromboembolic event was recorded. Four bleeding events (5.3%) were reported, 3 of which were considered major bleeding events (2 fatal). Suspending vitamin K antagonists with no bridging therapy performed in patients with a low thromboembolic risk does not expose such patients to a significant risk of embolic events. Copyright © 2017 Elsevier España, S.L.U. All rights reserved.

  2. Differential effects of ghrelin antagonists on alcohol drinking and reinforcement in mouse and rat models of alcohol dependence

    Science.gov (United States)

    Gomez, Juan L.; Cunningham, Christopher L.; Finn, Deborah A.; Young, Emily A.; Helpenstell, Lily K.; Schuette, Lindsey M.; Fidler, Tara L.; Kosten, Therese A.; Ryabinin, Andrey E.

    2015-01-01

    An effort has been mounted to understand the mechanisms of alcohol dependence in a way that may allow for greater efficacy in treatment. It has long been suggested that drugs of abuse seize fundamental reward pathways and disrupt homeostasis to produce compulsive drug seeking behaviors. Ghrelin, an endogenous hormone that affects hunger state and release of growth hormone, has been shown to increased alcohol intake following administration, while antagonists decrease intake. Using rodent models of dependence, the current study examined the effects of two ghrelin receptor antagonists, [DLys3]-GHRP-6 (DLys) and JMV2959, on dependence-induced alcohol self-administration. In two experiments adult male C57BL/6J mice and Wistar rats were made dependent via intermittent ethanol vapor exposure. In another experiment, adult male C57BL/6J mice were made dependent using the intragastric alcohol consumption (IGAC) procedure. Ghrelin receptor antagonists were given prior to voluntary ethanol drinking. Ghrelin antagonists reduced ethanol intake, preference, and operant self-administration of ethanol and sucrose across these models, but did not decrease food consumption in mice. In experiments 1 and 2, voluntary drinking was reduced by ghrelin receptor antagonists, however this reduction did not persist across days. Despite the transient effects to ghrelin antagonists, the drugs had renewed effectiveness following a break in administration as seen in experiment 1. The results show the ghrelin system as a potential target for studies of alcohol abuse. Further research is needed to determine the central mechanisms of these drugs and their influence on addiction in order to design effective pharmacotherapies. PMID:26051399

  3. Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists

    Science.gov (United States)

    2016-08-01

    AWARD NUMBER: W81XWH-15 1-0252 TITLE: Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists PRINCIPAL INVESTIGATOR...14 Jul 2016 4. TITLE AND SUBTITLE Enhanced Chronic Pain Management Utilizing Chemokine Receptor Antagonists 5a. CONTRACT NUMBER 5b. GRANT...Center for Substance Abuse Research Lewis Katz School of Medicine at Temple University 3500 N, Broad Street Philadelphia, PA 19140 AND ADDRESS(ES) 8

  4. Interleukin-2 receptor antagonists as induction therapy after heart transplantation

    DEFF Research Database (Denmark)

    Møller, Christian H; Gustafsson, Finn; Gluud, Christian

    2008-01-01

    About half of the transplantation centers use induction therapy after heart transplantation. Interleukin-2 receptor antagonists (IL-2Ras) are used increasingly for induction therapy. We conducted a systematic review of randomized trials assessing IL-2Ras.......About half of the transplantation centers use induction therapy after heart transplantation. Interleukin-2 receptor antagonists (IL-2Ras) are used increasingly for induction therapy. We conducted a systematic review of randomized trials assessing IL-2Ras....

  5. Reporter gene assay for the quantification of the activity and neutralizing antibody response to TNFα antagonists

    DEFF Research Database (Denmark)

    Lallemand, Christophe; Kavrochorianou, Nadia; Steenholdt, Casper

    2011-01-01

    A cell-based assay has been developed for the quantification of the activity of TNFα antagonists based on human erythroleukemic K562 cells transfected with a NFκB regulated firefly luciferase reporter-gene construct. Both drug activity and anti-drug neutralizing antibodies can be quantified...... with a high degree of precision within 2h, and without interference from cytokines and other factors known to activate NFκB. The assay cells also contain the Renilla luciferase reporter gene under the control of a constitutive promoter that allows TNFα-induced firefly luciferase activity to be normalized...

  6. Churg-Strauss syndrome and leukotriene antagonist use: a respiratory perspective.

    LENUS (Irish Health Repository)

    Nathani, N

    2008-10-01

    Churg-Strauss syndrome (CSS) is a rare granulomatous small vessel vasculitis that occurs against a background of longstanding asthma. Leukotriene antagonists (LTAs) are used in the management of asthma and may facilitate a reduction in steroid dosage. Reports of the development of CSS in patients with asthma following the initiation of LTA therapy suggest either a causal association or an unmasking of latent CSS as steroid doses fall. We have undertaken a systematic review to establish whether evidence of a drug induced syndrome exists.

  7. Preclinical anticonvulsant and neuroprotective profile of 8319, a non-competitive NMDA antagonist

    International Nuclear Information System (INIS)

    Fielding, S.; Wilker, J.C.; Chernack, J.; Ramirez, V.; Wilmot, C.A.; Martin, L.L.; Payack, J.F.; Cornfeldt, M.L.; Rudolphi, K.A.; Rush, D.K.

    1990-01-01

    8319, ((+-)-2-Amino-N-ethyl-alpha-(3-methyl-2-thienyl)benzeneethanamine 2HCl), is a novel compound with the profile of a non-competitive NMDA antagonist. The compound displaced [3H] TCP with high affinity (IC50 = 43 nM), but was inactive at the NMDA, benzodiazepine and GABA sites; in vivo, 8319 showed good efficacy as an anticonvulsant and potential neuroprotective agent. It blocked seizures induced by NMDLA, supramaximal electroshock, pentylenetetrazol (PTZ), picrotoxin, and thiosemicarbazide with ED50's of 1-20 mg/kg ip. As a neuroprotective agent, 8319 (30-100 mg/kg sc) prevented the death of dorsal hippocampal pyramidal cells induced by direct injection of 20 nmol NMDA. At 15 mg/kg ip, the compound was also effective against hippocampal neuronal necrosis induced via bilateral occlusion of the carotid arteries in gerbils. In summary, 8319 is a noncompetitive NMDA antagonist with good anticonvulsant activity and may possess neuroprotective properties useful in the treatment of brain ischemia

  8. Platelet-activating factor (PAF)-antagonists of natural origin.

    Science.gov (United States)

    Singh, Preeti; Singh, Ishwari Narayan; Mondal, Sambhu Charan; Singh, Lubhan; Garg, Vipin Kumar

    2013-01-01

    Presently herbal medicines are being used by about 80% of the world population for primary health care as they stood the test of time for their safety, efficacy, cultural acceptability and lesser side effects. The discovery of platelet activating factor antagonists (PAF antagonists) during these decades are going on with different framework, but the researchers led their efficiency in studying in vitro test models. Since it is assumed that PAF play a central role in etiology of many diseases in humans such as asthma, neuronal damage, migraine, cardiac diseases, inflammatory, headache etc. Present days instinctively occurring PAF antagonist exists as a specific grade of therapeutic agents for the humans against these and different diseases either laid hold of immunological or non-immunological types. Ginkgolide, cedrol and many other natural PAF antagonists such as andrographolide, α-bulnesene, cinchonine, piperine, kadsurenone, different Piper species' natural products and marine origin plants extracts or even crude drugs having PAF antagonist properties are being used currently against different inflammatory pathologies. This review is an attempt to summarize the data on PAF and action of natural PAF antagonists on it, which were evaluated by in vivo and in vitro assays. Copyright © 2012 Elsevier B.V. All rights reserved.

  9. Broad-spectrum antiemetic potential of the L-type calcium channel antagonist nifedipine and evidence for its additive antiemetic interaction with the 5-HT(3) receptor antagonist palonosetron in the least shrew (Cryptotis parva).

    Science.gov (United States)

    Darmani, Nissar A; Zhong, Weixia; Chebolu, Seetha; Vaezi, Mariam; Alkam, Tursun

    2014-01-05

    Cisplatin-like chemotherapeutics cause vomiting via release of multiple neurotransmitters (dopamine, serotonin (5-HT), or substance P (SP)) from the gastrointestinal enterochromaffin cells and/or the brainstem via a calcium dependent process. Diverse channels in the plasma membrane allow extracellular Ca(2+) entry into cells for the transmitter release process. Agonists of 5-HT3 receptors increase calcium influx through both 5-HT3 receptors and L-type Ca(2+) channels. We envisaged that L-type calcium agonists such as FPL 64176 should cause vomiting and corresponding antagonists such as nifedipine would behave as broad-spectrum antiemetics. Administration of FPL 64176 did cause vomiting in the least shrew in a dose-dependent fashion. Nifedipine and the 5-HT3 receptor antagonist palonosetron, potently suppressed FPL 64176-induced vomiting, while a combination of ineffective doses of these antagonists was more efficacious. Subsequently, we investigated the broad-spectrum antiemetic potential of nifedipine against diverse emetogens including agonists of serotonergic 5-HT3- (e.g. 5-HT or 2-Me-5-HT), SP tachykinin NK1- (GR73632), dopamine D2- (apomorphine or quinpirole), and cholinergic M1- (McN-A-343) receptors, as well as the non-specific emetogen, cisplatin. Nifedipine by itself suppressed vomiting in a potent and dose-dependent manner caused by the above emetogens except cisplatin. Moreover, low doses of nifedipine potentiated the antiemetic efficacy of non-effective or semi-effective doses of palonosetron against vomiting caused by either 2-Me-5-HT or cisplatin. Thus, our findings demonstrate that activation of L-type calcium channels causes vomiting, whereas blockade of these ion channels by nifedipine-like antagonists not only provides broad-spectrum antiemetic activity but can also potentiate the antiemetic efficacy of well-established antiemetics such as palonosetron. L-type calcium channel antagonists should also provide antiemetic activity against drug-induced

  10. alpha2-Adrenoceptor antagonists reverse the 5-HT2 receptor antagonist suppression of head-twitch behavior in mice.

    Science.gov (United States)

    Matsumoto, K; Mizowaki, M; Thongpraditchote, S; Murakami, Y; Watanabe, H

    1997-03-01

    The alpha2-adrenoceptor agonist clonidine, as well as 5-HT2 receptor antagonists, reportedly suppress 5-HT2 receptor-mediated head-twitch behavior. We investigated the effect of alpha2-adrenoceptor antagonists on the suppressive action of 5-HT2 receptor antagonists in mice pretreated with the noradrenaline toxin 6-hydroxydopamine (6-OHDA) or the 5-HT synthesis inhibitor p-chlorophenylalanine (p-CPA). In normal mice, idazoxan (0.08-0.2 mg/kg, IP) or yohimbine (0.2-2.0 mg/kg, IP), both alpha2-adrenoceptor antagonists, had no effect on the head-twitch response caused by 5-methoxy-N,N-dimethyltryptamine (5-MeO-DMT; 16 mg/kg, IP), but idazoxan significantly enhanced the response at 0.5 mg/kg. On the other hand, these alpha2-adrenoceptor antagonists, at doses that had no effect on the basal number of head-twitches (idazoxan 0.2 mg/kg and yohimbine 0.5 mg/kg), significantly attenuated not only the suppressive effect of clonidine (0.01 mg/kg, IP) on head-twitch response but also that of the 5-HT2 receptor antagonist ritanserin (0.03 mg/kg, IP). Moreover, idazoxan (0.2 mg/kg) also significantly reversed the inhibition by 0.01 mg/kg (IP) ketanserin, a selective 5-HT2 receptor antagonist. Pretreatment with 6-OHDA plus nomifensine but not with p-CPA significantly attenuated the effect of idazoxan (0.2-0.5 mg/kg) on the ritanserin inhibition of the head-twitch response. Prazosin, an alpha1-adrenoceptor antagonist, dose-dependently suppressed the response, and the effect of prazosin (1.25 mg/kg) was significantly attenuated by 0.5 mg/kg idazoxan. These results indicate that endogenous noradrenaline is involved in the apparent antagonistic interaction between selective alpha2-adrenoceptor antagonists and 5-HT2 receptor antagonists in the head-twitch response, and suggest that noradrenaline stimulation of alpha1-adrenoceptors may be involved in this apparent antagonism.

  11. BQ-869, a novel NMDA receptor antagonist, protects against excitotoxicity and attenuates cerebral ischemic injury in stroke.

    Science.gov (United States)

    Yu, Guo; Wu, Fei; Wang, Er-Song

    2015-01-01

    Stroke is one of the three diseases that cause human death in current world, and it is the common, frequently occurring disease in the middle-old ages. NMDA receptors mediate glutamate-induced cell death when intensely or chronically activated, which is an important cause of neuronal cell death after acute injuries. Here, we demonstrated that BQ-869, a potent NMDA receptor antagonist, blocked NMDA receptor in concentration-dependent and dose-dependent manner, attenuated NMDA-induced Ca(2+) influx, inhabited NMDAR-mEPSC in hippocampal pyramidal neurons, improved athletic ability of rats with MACO, decreased infarction size in focal cerebral ischemia rats and reduced stroke mortality. Taken together, our data demonstrate the neuroprotective effect of BQ-869 might be through inhibiting NMDA-mediated excitotoxicity. These findings indicate that BQ-869 is the most potent antagonist of NMDA receptors, and provide new insights with potential therapeutic applications for the treatment of stroke.

  12. Vitamin K antagonist use and mortality in dialysis patients.

    Science.gov (United States)

    Voskamp, Pauline W M; Rookmaaker, Maarten B; Verhaar, Marianne C; Dekker, Friedo W; Ocak, Gurbey

    2018-01-01

    The risk-benefit ratio of vitamin K antagonists for different CHA2DS2-VASc scores in patients with end-stage renal disease treated with dialysis is unknown. The aim of this study was to investigate the association between vitamin K antagonist use and mortality for different CHA2DS2-VASc scores in a cohort of end-stage renal disease patients receiving dialysis treatment. We prospectively followed 1718 incident dialysis patients. Hazard ratios were calculated for all-cause and cause-specific (stroke, bleeding, cardiovascular and other) mortality associated with vitamin K antagonist use. Vitamin K antagonist use as compared with no vitamin K antagonist use was associated with a 1.2-fold [95% confidence interval (95% CI) 1.0-1.5] increased all-cause mortality risk, a 1.5-fold (95% CI 0.6-4.0) increased stroke mortality risk, a 1.3-fold (95% CI 0.4-4.2) increased bleeding mortality risk, a 1.2-fold (95% CI 0.9-1.8) increased cardiovascular mortality risk and a 1.2-fold (95% CI 0.8-1.6) increased other mortality risk after adjustment. Within patients with a CHA2DS2-VASc score ≤1, vitamin K antagonist use was associated with a 2.8-fold (95% CI 1.0-7.8) increased all-cause mortality risk as compared with no vitamin K antagonist use, while vitamin K antagonist use within patients with a CHA2DS2-VASc score ≥2 was not associated with an increased mortality risk after adjustment. Vitamin K antagonist use was not associated with a protective effect on mortality in the different CHA2DS2-VASc scores in dialysis patients. The lack of knowledge on the indication for vitamin K antagonist use could lead to confounding by indication. © The Author 2017. Published by Oxford University Press on behalf of ERA-EDTA. All rights reserved.

  13. Pain-releasing action of platelet-activating factor (PAF) antagonists in neuropathic pain animal models and the mechanisms of action.

    Science.gov (United States)

    Motoyama, N; Morita, K; Kitayama, T; Shiraishi, S; Uezono, Y; Nishimura, F; Kanematsu, T; Dohi, T

    2013-09-01

    Platelet-activating factor (PAF) has been implicated in the pathology of neuropathic pain. Previous studies reported that PAF receptor (PAF-R) antagonists have varied anti-allodynia effects by route of administration and nerve injury models in rats. The present study elucidated the effectiveness of PAF antagonists against neuropathic pain in four different models of peripheral nerve injury and provided insights into the mode of anti-allodynia action. PAF antagonists, TCV-309, BN 50739 and WEB 2086 by intravenous (i.v.) and oral administration have potent and long-lasting anti-allodynia action in mice neuropathic pain models. Treatment with PAF antagonists before surgery delayed the initiation of allodynia until the effects of these treatments were abolished. Intrathecal (i.t.) injection of the PAF antagonists and siRNA against PAF receptor ameliorated allodynia. I.t. injection of the glycine receptor (GlyR)α3 siRNA reduced the anti-allodynia effect of PAF antagonists. This evidence suggests that the anti-allodynia effect of PAF antagonists is at least in part mediated by spinal relief of PAF-induced dysfunction of GlyRα3. An analysis of the mode of anti-allodynia action of TCV-309 in vivo revealed a competitive action against PAF shortly after the injection of TCV-309, converting to a non-competitive action later. The present results revealed the effectiveness in anti-allodynia of PAF antagonists in different nerve injury models, and the unique mode of action; long-lasting anti-allodynia effects mediated by spinal GlyRα3 with a competitive manner at the initial stage and the following non-competitive manner of inhibition. © 2013 European Federation of International Association for the Study of Pain Chapters.

  14. Evidence that the angiotensin at 2-receptor agonist compound 21 is also a low affinity thromboxane TXA2-receptor antagonist

    DEFF Research Database (Denmark)

    Fredgart, M.; Leurgans, T.; Stenelo, M.

    2015-01-01

    AT2-receptor specificity, arteries were pre-incubated with the AT2-receptor antagonist PD123319 (10muM), or mesenteric arteries from AT2-receptor knock-out (AT2R-/y) mice were used. An inhibitory effect of C21 (100nM - 10muM) on U46619 (0,3muM) induced platelet aggregation was examined in whole human...

  15. Serotonin 5-HT(2A) receptor antagonists in the treatment of insomnia: present status and future prospects.

    Science.gov (United States)

    Monti, J M

    2010-03-01

    Benzodiazepine (BZD) and non-BZD hypnotics improve sleep induction and sleep maintenance. BZD induces a further reduction of slow wave sleep (SWS) and rapid eye movement (REM) sleep, whereas SWS and REM values remain decreased during non-BZD administration. There is evidence indicating that the nonselective serotonin 5-HT(2A/2C) receptor antagonists, ritanserin, ketanserin, seganserin and ICI-169369, the selective 5-HT(2A) receptor antagonist eplivanserin and the 5-HT(2A) receptor inverse agonist pimavanserin, increase SWS in subjects with normal sleep. In addition, it has been shown that prior administration of ritanserin prevents the nitrazepam-induced suppression of SWS in normal subjects. Of note, ritanserin also induced an increase of SWS in poor sleepers, patients with chronic primary insomnia and psychiatric patients with a generalized anxiety disorder or a mood disorder. The 5-HT(2A) receptor inverse agonist APD-125 gave rise to a similar effect in patients with chronic primary insomnia. Thus, presently available evidence tends to indicate that the association of a 5-HT(2A) receptor antagonist or a 5-HT(2A) receptor inverse agonist with a BZD or a non-BZD hypnotic could be a valid alternative to normalize SWS in patients with primary or comorbid insomnia. Copyright 2010 Prous Science, S.A.U. or its licensors. All rights reserved.

  16. P2X1 Receptor Antagonists Inhibit HIV-1 Fusion by Blocking Virus-Coreceptor Interactions

    Science.gov (United States)

    Giroud, Charline; Marin, Mariana; Hammonds, Jason; Spearman, Paul

    2015-01-01

    receptor antagonist, NF279, is due to the blocking of virus interactions with both the CXCR4 and CCR5 coreceptors. The ability of NF279 to abrogate cellular calcium signaling induced by the respective chemokines showed that this compound acts as a dual-coreceptor antagonist. P2X1 receptor antagonists could thus represent a new class of dual-coreceptor inhibitors with a structure and a mechanism of action that are distinct from those of known HIV-1 coreceptor antagonists. PMID:26136569

  17. Rapid induction of expression by LPS is accompanied by favorable chromatin and rapid binding of c-Jun.

    Science.gov (United States)

    Maurer, Kelly; Ramen, Swathi; Shi, Lihuaa; Song, Li; Sullivan, Kathleen E

    2018-03-01

    The response to infection is managed in mammals by a coordinated immune response. Innate responses are rapid and hard wired and have been demonstrated to be regulated at the level of chromatin accessibility. This study examined primary human monocyte responses to LPS as a model of innate responses to bacteria. We utilized inhibitors of chromatin modifying enzymes to understand the inter-relationships of the chromatin complexes regulating transcription. Multiplex digital gene detection was utilized to quantitate changes in mRNA levels for genes induced by LPS. In the first 30 min, genes that were highly induced by LPS as a group exhibited minimal effect of the chemical inhibitors of chromatin modifications. At 60 min, the more highly expressed genes were markedly more inhibitable. The effects of the inhibitors were almost entirely concordant in spite of different mechanisms of action. Two focus groups of genes with either high LPS inducibility at 30 min or high LPS inducibility at 60 min (but not at 30 min) were further examined by ChIP assay. NFκB p65 binding was increased at the promoters of 30- and 60-min highly inducible genes equivalently. Binding of c-Jun was increased after LPS in the 30-min inducible gene set but not the 60-min inducible gene set. H3K4me3 and H4ac were not detectably altered by LPS stimulation. Baseline H3K4me3 and H4ac were higher in the 30-min highly inducible gene set compared to the 60-min highly inducible gene set. NFκB and JNK inhibitors led to diminished H4ac after LPS. The effects of DRB and C646 were greater for LPS-induced IL6 transcription at 30 min and LPS-stimulated H4ac compared to TNF where transcription was largely unaffected by the inhibitors. In conclusion, genes with very rapidly induced expression after LPS exhibited more favorable chromatin characteristics at baseline and were less inhibitable than genes induced at the later time points. Copyright © 2018 Elsevier Ltd. All rights reserved.

  18. SCD5 restored expression favors differentiation and epithelial-mesenchymal reversion in advanced melanoma.

    Science.gov (United States)

    Puglisi, Rossella; Bellenghi, Maria; Pontecorvi, Giada; Gulino, Alessandro; Petrini, Marina; Felicetti, Federica; Bottero, Lisabianca; Mattia, Gianfranco; Carè, Alessandra

    2018-01-26

    Our previous data supported a role for the Stearoyl-CoA desaturase (SCD5) in protection against malignancy, whereby it appears to functionally modify tumor stroma impairing tumor spread. SCD5 is significantly expressed in primary melanoma, but becomes barely detectable at tumor advanced stages. Looking for the regulatory mechanisms underlying SCD5 reduced expression during melanoma progression, we demonstrated a significantly lower stability of SCD5 protein as well as the direct targeting of SCD5 mRNA by the oncogenic miR-221&222 in metastatic cell lines. Moreover, our results indicated the existence of a negative feedback loop between SCD5 and miR-221&222, in good agreement with their opposite functions. Also, we showed how SCD5 re-expression and the direct supplementation of its main product oleic acid (OA) can drive advanced melanoma cell lines toward differentiation and reversion of the epithelial-mesenchymal (EMT)-like process, eventually inducing a less malignant phenotype. Indeed, SCD5 re-established the sensitivity to all-trans retinoic acid in A375M metastatic melanoma, associated with increased levels of Tyrosinase, melanin production and reduced proliferation. As evidenced by the correct modulation of some key transcription factors, SCD5 managed by favoring a partial mesenchymal-to-epithelial (MET) transition in in vitro studies. Interestingly, a more complete MET, including E-cadherin re-expression correctly localized at cell membranes, was obtained in in vivo xenograft models, thus indicating the requirement of direct contacts between tumor cells and the surrounding microenvironment as well as the presence of some essential factors for SCD5 complete function.

  19. A generalização a partir do tratamento com fricativas: ambientes favoráveis versus ambientes pouco favoráveis e neutros The generalization through the treatment with fricatives: favorable environments versus unfavorable and neutral environments

    Directory of Open Access Journals (Sweden)

    Fernanda Marafiga Wiethan

    2013-01-01

    Full Text Available O objetivo deste estudo foi analisar e comparar a ocorrência e os tipos de generalização observados a partir do tratamento das fricativas /z/, /ζ/ e /k/ em dois grupos de crianças, um utilizando palavras com contextos fonológicos favoráveis e outro os contextos pouco favoráveis e neutros. Seis crianças com desvio fonológico e idades entre 4:7 e 7:8 participaram do estudo com a autorização dos responsáveis. Realizaram-se avaliações fonoaudiológicas e complementares para o diagnóstico do desvio fonológico. Os sujeitos foram pareados de acordo com a gravidade do desvio, sexo, faixa etária e aspectos do sistema fonológico em relação aos fonemas alterados. Metade das crianças foi tratada com palavras em que os fonemas /z/, /ζ/ e /k/ encontravam-se em ambientes fonológicos favoráveis e a outra metade com ambientes pouco favoráveis e neutros. Foram realizadas oito sessões e, após estas, nova avaliação de fala foi realizada para verificar os tipos de generalização obtidos. Os percentuais de generalizações foram comparados entre os grupos por meio do teste estatístico de Mann-Whitney (pThe aim of this study was to analyze and compare the occurrence and the types of generalization observed through the treatment of the fricatives /z/, /ζ/ and /k/ in two groups of children, one using words with favorable phonological contexts and another with unfavorable and neutral contexts. Six children with phonological disorder between 4:7 and 7:8 year-old participated in the study, with their parents' authorization. There were speech-language and complementary evaluations to diagnose the phonological disorder. The subjects were matched according to the severity of the phonological disorder, sex, age and aspects of the phonological system in relation to the altered phonemes. Half the children were treated with words in which the phonemes /z/, /ζ/ and /k/ were in favorable phonological environments and the other half with unfavorable

  20. The α1 Antagonist Doxazosin Alters the Behavioral Effects of Cocaine in Rats

    Directory of Open Access Journals (Sweden)

    Colin N. Haile

    2012-11-01

    Full Text Available Medications that target norepinephrine (NE neurotransmission alter the behavioral effects of cocaine and may be beneficial for stimulant-use disorders. We showed previously that the short-acting, α1-adrenergic antagonist, prazosin, blocked drug-induced reinstatement of cocaine-seeking in rats and doxazosin (DOX, a longer-acting α1 antagonist blocked cocaine’s subjective effects in cocaine-dependent volunteers. To further characterize DOX as a possible pharmacotherapy for cocaine dependence, we assessed its impact on the development and expression of cocaine-induced locomotor sensitization in rats. Rats (n = 6–8 were administered saline, cocaine (COC, 10 mg/kg or DOX (0.3 or 1.0 mg/kg alone or in combination for 5 consecutive days (development. Following 10-days of drug withdrawal, all rats were administered COC and locomotor activity was again assessed (expression. COC increased locomotor activity across days indicative of sensitization. The high dose (1.0 mg/kg, but not the low dose (0.3 mg/kg of DOX significantly decreased the development and expression of COC sensitization. DOX alone did not differ from saline. These results are consistent with studies showing that α1 receptors are essential for the development and expression of cocaine’s behavioral effects. Results also suggest that blockade of both the development and expression of locomotor sensitization may be important characteristics of possible pharmacotherapies for cocaine dependence in humans.

  1. Effect of SDF-1/Cxcr4 Signaling Antagonist AMD3100 on Bone Mineralization in Distraction Osteogenesis.

    Science.gov (United States)

    Xu, Jia; Chen, Yuanfeng; Liu, Yang; Zhang, Jinfang; Kang, Qinglin; Ho, Kiwai; Chai, Yimin; Li, Gang

    2017-06-01

    Distraction osteogenesis (DO) is a widely applied technique in orthopedics surgery, which involves rapid stem cell migration, homing, and differentiation. Interactions between the chemokine receptor Cxcr4 and its ligand, stromal derived factor-1 (SDF-1), regulate hematopoietic stem cell trafficking to the ischemic area and induce their subsequent differentiation. Here, we examined SDF-1 expression and further investigated the role of SDF-1/Cxcr4 signaling antagonist AMD3100 during bone regeneration in rat DO model. The results showed that expression levels of SDF-1 and osteogenic genes were higher in DO zones than in the fracture zones, and SDF-1 expression level was the highest at the termination of the distraction phase. Radiological, mechanical, and histological analyses demonstrated that the local administration of AMD3100 (400 μM) to DO rats significantly inhibited new bone formation. In the rat bone marrow mesenchymal stem cells culture, comparing to the group treated with osteogenic induction medium, AMD3100 supplement led to a considerable decrease in the expression of alkaline phosphatase and early osteogenic marker genes. However, the amount of calcium deposits in rat MSCs did not differ between the groups. Therefore, our study demonstrated that the DO process induced higher expression of SDF-1, which collated to rapid induction of callus formation. Local application of SDF-1/Cxcr4 signaling antagonist AMD3100 significantly inhibited bone mineralization and osteogenesis in DO, which may represent a potential therapeutic approach to the enhancement of bone consolidation in patients undergoing DO.

  2. Progesterone receptor antagonist CDB-4124 increases depression-like behavior in mice without affecting locomotor ability

    Science.gov (United States)

    Beckley, Ethan H.; Scibelli, Angela C.; Finn, Deborah A.

    2010-01-01

    Progesterone withdrawal has been proposed as an underlying factor in premenstrual syndrome and postpartum depression. Progesterone withdrawal induces forced swim test (FST) immobility in mice, a depression-like behavior, but the contribution of specific receptors to this effect is unclear. The role of progesterone’s GABAA receptor-modulating metabolite allopregnanolone in depression- and anxiety-related behaviors has been extensively documented, but little attention has been paid to the role of progesterone receptors. We administered the classic progesterone receptor antagonist mifepristone (RU-38486) and the specific progesterone receptor antagonist CDB-4124 to mice that had been primed with progesterone for five days, and found that both compounds induced FST immobility reliably, robustly, and in a dose-dependent fashion. Although CDB-4124 increased FST immobility, it did not suppress initial activity in a locomotor test. These findings suggest that decreased progesterone receptor activity contributes to depression-like behavior in mice, consistent with the hypothesis that progesterone withdrawal may contribute to the symptoms of premenstrual syndrome or postpartum depression. PMID:21163582

  3. G2 checkpoint abrogator abates the antagonistic interaction between antimicrotubule drugs and radiation therapy

    International Nuclear Information System (INIS)

    Sui Meihua; Zhang Hongfang; Di Xiaoyun; Chang Jinjia; Shen Youqing; Fan Weimin

    2012-01-01

    Background and purpose: We previously demonstrated that radiation may arrest tumor cells at G2 phase, which in turn prevents the cytotoxicity of antimicrotubule drugs and results in antagonistic interaction between these two modalities. Herein we tested whether G2 abrogators would attenuate the above antagonistic interaction and improve the therapeutic efficacy of combination therapy between radiation and antimicrotubule drugs. Materials and methods: Breast cancer BCap37 and epidermoid carcinoma KB cell lines were administered with radiation, UCN-01 (a model drug of G2 abrogator), paclitaxel or vincristine, alone or in combinations. The antitumor activities of single and combined treatments were analyzed by a series of cytotoxic, apoptotic, cell cycle, morphological and biochemical assays. Results: UCN-01 significantly enhanced the cytotoxicity of radiation, antimitotic drugs, and their combined treatments in vitro. Further investigations demonstrated that UCN-01 attenuated radiation-induced G2 arrest, and subsequently repressed the inhibitory effect of radiation on drug-induced mitotic arrest and apoptosis. Conclusions: This is the first report demonstrating that G2 checkpoint abrogation represses the inhibitory effect of radiation on antimicrotubule drugs, which may be implicated in cancer combination therapy. Considering that G2 abrogators are under extensive evaluation for cancer treatment, our findings provide valuable information for this class of promising compounds.

  4. Reduction of opioid dependence by the CB(1) antagonist SR141716A in mice: evaluation of the interest in pharmacotherapy of opioid addiction.

    Science.gov (United States)

    Mas-Nieto, M; Pommier, B; Tzavara, E T; Caneparo, A; Da Nascimento, S; Le Fur, G; Roques, B P; Noble, F

    2001-04-01

    Several compounds, mainly opioid agonists such as methadone, are currently used for long term medication of heroin addicts. Nevertheless, these maintenance treatments have the disadvantage to induce a dependence to another opiate. As interactions between opioid and cannabinoid systems have been demonstrated, the ability of the CB(1) antagonist, SR141716A to reduce morphine-induced addiction was investigated. The effects of SR141716A on the rewarding responses of morphine were evaluated in the place conditioning paradigm. No significant conditioned preference or aversion were observed after repeated treatment with the CB(1) antagonist alone. However, SR141716A was able to antagonize the acquisition of morphine-induced conditioned place preference. SR141716A was co-administered with morphine for 5 days, and the withdrawal syndrome was precipitated by naloxone administration. A reduction in the incidence of two main signs of abstinence: wet dog shakes and jumping was observed while the other were not significantly modified. In contrast, an acute injection of the CB(1) antagonist just before naloxone administration was unable to modify the incidence of the behavioural manifestations of the withdrawal, suggesting that only chronic blockade of CB(1) receptors is able to reduce morphine-induced physical dependence. Several biochemical mechanisms could explain the reduction of opioid dependence by CB(1) antagonists. Whatever the hypotheses, this study supports the reported interaction between the endogenous cannabinoid and opioid systems, and suggests that SR 141716A warrants further investigations for a possible use in opioid addiction.

  5. The inhibitory effect of newer calcium antagonists (nimodipine and PY-108-068) on vasoconstriction in vivo mediated by postsynaptic alpha 2-adrenoceptors

    NARCIS (Netherlands)

    Van Meel, J. C. A.; Wilffert, B; De Zoeten, K; Timmermans, P B; Van Zwieten, P A

    1982-01-01

    In the pithed rat, stimulation of postsynaptic alpha 1 as well as alpha 2-adrenoceptors is known to cause vasoconstriction. The two newer nifedipine-related calcium antagonistic agents nimodipine and PY-108-068 proved potent inhibitors of pressor responses induced by the selective alpha 2-receptor

  6. Triazole GHS-R1a antagonists JMV4208 and JMV3002 attenuate food intake, body weight, and adipose tissue mass in mice

    Czech Academy of Sciences Publication Activity Database

    Holubová, Martina; Nagelová, Veronika; Lacinová, Z.; Haluzík, M.; Sýkora, D.; Moulin, A.; Blayo, A. L.; Fehrentz, J. A.; Martinez, J.; Stofková, A.; Jurčovičová, J.; Železná, Blanka; Maletínská, Lenka

    2014-01-01

    Roč. 393, 1/2 (2014), s. 120-128 ISSN 0303-7207 Institutional support: RVO:61388963 Keywords : GHS-R1a antagonists * diet-induced obesity * food intake * JMV4208 * JMV3002 * male C57BL/6 mice Subject RIV: CE - Biochemistry Impact factor: 4.405, year: 2014

  7. Phase III trial of casopitant, a novel neurokinin-1 receptor antagonist, for the prevention of nausea and vomiting in patients receiving moderately emetogenic chemotherapy

    DEFF Research Database (Denmark)

    Herrstedt, Jørn; Apornwirat, Wichit; Shaharyar, Ahmed

    2009-01-01

    PURPOSE: The purpose of this phase III trial was to evaluate the efficacy and safety of regimens containing casopitant, a novel neurokinin-1 receptor antagonist, for the prevention of chemotherapy-induced nausea and vomiting during the first cycle in patients receiving moderately emetogenic chemo...

  8. First Irish birth following IVF therapy using antagonist protocol.

    LENUS (Irish Health Repository)

    Mocanu, E V

    2012-02-01

    BACKGROUND: During in vitro fertilization (IVF), the prevention of a premature LH surge was traditionally achieved using a gonadotrophin releasing hormone agonist (GnRH-a), and more recently, a GnRH antagonist. AIMS: We report a case of a 37 year old treated using the GnRH antagonist in a second completed cycle of IVF. METHODS: IVF was performed for primary infertility of 5-year duration due to frozen pelvis secondary to endometriosis. RESULTS: Following controlled ovarian hyperstimulation, oocyte recovery and fertilization, cleavage and transfer of two zygotes, a pregnancy established. A twin gestation was diagnosed at 7-weeks scan and pregnancy ended with the delivery of twin girls by emergency caesarean section. CONCLUSION: This is a first report of a delivery following IVF using the antagonist protocol in Ireland. Such therapy is patient friendly and its use should be introduced on a larger scale in clinical practice.

  9. GnRH antagonist versus long agonist protocols in IVF

    DEFF Research Database (Denmark)

    Lambalk, C B; Banga, F R; Huirne, J A

    2017-01-01

    was not the only variable between the compared study arms. OBJECTIVE AND RATIONALE: The aim of the current study was to compare GnRH antagonist protocols versus standard long agonist protocols in couples undergoing IVF or ICSI, while accounting for various patient populations and treatment schedules. SEARCH......BACKGROUND: Most reviews of IVF ovarian stimulation protocols have insufficiently accounted for various patient populations, such as ovulatory women, women with polycystic ovary syndrome (PCOS) or women with poor ovarian response, and have included studies in which the agonist or antagonist...... METHODS: The Cochrane Menstrual Disorders and Subfertility Review Group specialized register of controlled trials and Pubmed and Embase databases were searched from inception until June 2016. Eligible trials were those that compared GnRH antagonist protocols and standard long GnRH agonist protocols...

  10. ANTAGONISTIC BACTERIA AGAINST SCHIZOPHYLLUM COMMUNE FR. IN PENINSULAR MALAYSIA

    Directory of Open Access Journals (Sweden)

    ANTARJO DIKIN

    2006-01-01

    Full Text Available Schizophyllum commune Fr., is one of the important fungi, causes brown germ and seed rot of oil palm. Biodiversity of antagonistic bacteria from oil palm plantations in Peninsular Malaysia is expected to support in development of biopesticide. Isolation with liquid assay and screening antagonistic bacteria using dual culture assay were carried out in the bioexploration. A total of 265 bacterial isolates from plant parts of oil palm screened 52 antagonistic bacterial isolates against 5. commune. Bacterial isolates were identified by using Biolog* Identification System i.e. Bacillus macroccanus, B. thermoglucosidasius, Burkholderia cepacia, B. gladioli, B. multivorans, B pyrrocinia, B. spinosa, Corynebacterium agropyri, C. misitidis, Enterobacter aerogenes, Microbacterium testaceum, Pseudomonas aeruginosa, P. citronellolis, Rhodococcus rhodochrous, Serratia ficaria, Serratia sp., S. marcescens, Staphylococcus sciuri, Sternotrophomonas maltophilia.

  11. Histamine H4 receptor antagonists: the new antihistamines?

    Science.gov (United States)

    Fung-Leung, Wai-Ping; Thurmond, Robin L; Ling, Ping; Karlsson, Lars

    2004-11-01

    Antihistamines (histamine H1 receptor antagonists) are a mainstay treatment for atopic allergy, yet they are only partially effective in relieving the symptoms of the disease. They also have very limited value for the treatment of asthma, despite the well-characterized bronchoconstrictory effects of histamine. The recent discovery of a fourth histamine receptor (H4), and the realization that it is exclusively expressed on hematopoietic cell types that are most implicated in the development and symptomatology of allergy and asthma, suggests that pharmacological targeting of the H4 receptor, either alone or in combination with H1 receptor antagonists, may prove useful for treating both allergy and asthma. Here we review the known biology associated with the H4 receptor, as well the effects of a highly selective H1 receptor antagonist.

  12. The Antidepressant 5-HT2A Receptor Antagonists Pizotifen and Cyproheptadine Inhibit Serotonin-Enhanced Platelet Function

    Science.gov (United States)

    Lin, Olivia A.; Karim, Zubair A.; Vemana, Hari Priya; Espinosa, Enma V. P.; Khasawneh, Fadi T.

    2014-01-01

    There is considerable interest in defining new agents or targets for antithrombotic purposes. The 5-HT2A receptor is a G-protein coupled receptor (GPCR) expressed on many cell types, and a known therapeutic target for many disease states. This serotonin receptor is also known to regulate platelet function. Thus, in our FDA-approved drug repurposing efforts, we investigated the antiplatelet activity of cyproheptadine and pizotifen, two antidepressant 5-HT2A Receptor antagonists. Our results revealed that cyproheptadine and pizotifen reversed serotonin-enhanced ADP-induced platelet aggregation in vitro and ex vivo. And the inhibitory effects of these two agents were found to be similar to that of EMD 281014, a 5-HT2A Receptor antagonist under development. In separate experiments, our studies revealed that these 5-HT2A receptor antagonists have the capacity to reduce serotonin-enhanced ADP-induced elevation in intracellular calcium levels and tyrosine phosphorylation. Using flow cytometry, we also observed that cyproheptadine, pizotifen, and EMD 281014 inhibited serotonin-enhanced ADP-induced phosphatidylserine (PS) exposure, P-selectin expression, and glycoprotein IIb-IIIa activation. Furthermore, using a carotid artery thrombosis model, these agents prolonged the time for thrombotic occlusion in mice in vivo. Finally, the tail-bleeding time was investigated to assess the effect of cyproheptadine and pizotifen on hemostasis. Our findings indicated prolonged bleeding time in bo