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Sample records for acute pharmacological inhibition

  1. Pharmacological inhibition of FTO.

    PubMed

    McMurray, Fiona; Demetriades, Marina; Aik, WeiShen; Merkestein, Myrte; Kramer, Holger; Andrew, Daniel S; Scudamore, Cheryl L; Hough, Tertius A; Wells, Sara; Ashcroft, Frances M; McDonough, Michael A; Schofield, Christopher J; Cox, Roger D

    2015-01-01

    In 2007, a genome wide association study identified a SNP in intron one of the gene encoding human FTO that was associated with increased body mass index. Homozygous risk allele carriers are on average three kg heavier than those homozygous for the protective allele. FTO is a DNA/RNA demethylase, however, how this function affects body weight, if at all, is unknown. Here we aimed to pharmacologically inhibit FTO to examine the effect of its demethylase function in vitro and in vivo as a first step in evaluating the therapeutic potential of FTO. We showed that IOX3, a known inhibitor of the HIF prolyl hydroxylases, decreased protein expression of FTO (in C2C12 cells) and reduced maximal respiration rate in vitro. However, FTO protein levels were not significantly altered by treatment of mice with IOX3 at 60 mg/kg every two days. This treatment did not affect body weight, or RER, but did significantly reduce bone mineral density and content and alter adipose tissue distribution. Future compounds designed to selectively inhibit FTO's demethylase activity could be therapeutically useful for the treatment of obesity.

  2. Pharmacological Inhibition of FTO

    PubMed Central

    McMurray, Fiona; Demetriades, Marina; Aik, WeiShen; Merkestein, Myrte; Kramer, Holger; Andrew, Daniel S.; Scudamore, Cheryl L.; Hough, Tertius A.; Wells, Sara; Ashcroft, Frances M.; McDonough, Michael A.; Schofield, Christopher J.; Cox, Roger D.

    2015-01-01

    In 2007, a genome wide association study identified a SNP in intron one of the gene encoding human FTO that was associated with increased body mass index. Homozygous risk allele carriers are on average three kg heavier than those homozygous for the protective allele. FTO is a DNA/RNA demethylase, however, how this function affects body weight, if at all, is unknown. Here we aimed to pharmacologically inhibit FTO to examine the effect of its demethylase function in vitro and in vivo as a first step in evaluating the therapeutic potential of FTO. We showed that IOX3, a known inhibitor of the HIF prolyl hydroxylases, decreased protein expression of FTO (in C2C12 cells) and reduced maximal respiration rate in vitro. However, FTO protein levels were not significantly altered by treatment of mice with IOX3 at 60 mg/kg every two days. This treatment did not affect body weight, or RER, but did significantly reduce bone mineral density and content and alter adipose tissue distribution. Future compounds designed to selectively inhibit FTO’s demethylase activity could be therapeutically useful for the treatment of obesity. PMID:25830347

  3. Pharmacological inhibition of PAR2 with the pepducin P2pal-18S protects mice against acute experimental biliary pancreatitis

    PubMed Central

    Michael, E. S.; Kuliopulos, A.; Covic, L.; Steer, M. L.

    2013-01-01

    Pancreatic acinar cells express proteinase-activated receptor-2 (PAR2) that is activated by trypsin-like serine proteases and has been shown to exert model-specific effects on the severity of experimental pancreatitis, i.e., PAR2−/− mice are protected from experimental acute biliary pancreatitis but develop more severe secretagogue-induced pancreatitis. P2pal-18S is a novel pepducin lipopeptide that targets and inhibits PAR2. In studies monitoring PAR2-stimulated intracellular Ca2+ concentration changes, we show that P2pal-18S is a full PAR2 inhibitor in acinar cells. Our in vivo studies show that P2pal-18S significantly reduces the severity of experimental biliary pancreatitis induced by retrograde intraductal bile acid infusion, which mimics injury induced by endoscopic retrograde cholangiopancreatography (ERCP). This reduction in pancreatitis severity is observed when the pepducin is given before or 2 h after bile acid infusion but not when it is given 5 h after bile acid infusion. Conversely, P2pal-18S increases the severity of secretagogue-induced pancreatitis. In vitro studies indicate that P2pal-18S protects acinar cells against bile acid-induced injury/death, but it does not alter bile acid-induced intracellular zymogen activation. These studies are the first to report the effects of an effective PAR2 pharmacological inhibitor on pancreatic acinar cells and on the severity of experimental pancreatitis. They raise the possibility that a pepducin such as P2pal-18S might prove useful in the clinical management of patients at risk for developing severe biliary pancreatitis such as occurs following ERCP. PMID:23275617

  4. Pharmacological inhibition of PAR2 with the pepducin P2pal-18S protects mice against acute experimental biliary pancreatitis.

    PubMed

    Michael, E S; Kuliopulos, A; Covic, L; Steer, M L; Perides, G

    2013-03-01

    Pancreatic acinar cells express proteinase-activated receptor-2 (PAR2) that is activated by trypsin-like serine proteases and has been shown to exert model-specific effects on the severity of experimental pancreatitis, i.e., PAR2(-/-) mice are protected from experimental acute biliary pancreatitis but develop more severe secretagogue-induced pancreatitis. P2pal-18S is a novel pepducin lipopeptide that targets and inhibits PAR2. In studies monitoring PAR2-stimulated intracellular Ca(2+) concentration changes, we show that P2pal-18S is a full PAR2 inhibitor in acinar cells. Our in vivo studies show that P2pal-18S significantly reduces the severity of experimental biliary pancreatitis induced by retrograde intraductal bile acid infusion, which mimics injury induced by endoscopic retrograde cholangiopancreatography (ERCP). This reduction in pancreatitis severity is observed when the pepducin is given before or 2 h after bile acid infusion but not when it is given 5 h after bile acid infusion. Conversely, P2pal-18S increases the severity of secretagogue-induced pancreatitis. In vitro studies indicate that P2pal-18S protects acinar cells against bile acid-induced injury/death, but it does not alter bile acid-induced intracellular zymogen activation. These studies are the first to report the effects of an effective PAR2 pharmacological inhibitor on pancreatic acinar cells and on the severity of experimental pancreatitis. They raise the possibility that a pepducin such as P2pal-18S might prove useful in the clinical management of patients at risk for developing severe biliary pancreatitis such as occurs following ERCP.

  5. [Pharmacological treatment of acute catatonia].

    PubMed

    Cárdenas-Delgado, Christian L

    2012-01-01

    Catatonia is a neuropsychiatric syndrome of psychomotor dysregulation that can be present in a broad spectrum of clinical situations. Advances made over the last decades have progressively contributed to its clinical differentiation and its conceptual delimitation. Both Benzodiazepines (BZD) and Electroconvulsive therapy (ECT) have been consolidated as first-line therapy. In this regard, a BZD response rate ranging from 70 to 90 per cent has been reported in different case series. Furthermore, NMDA receptor antagonists represent an emerging strategy in the therapeutic approach to the disorder. Most of the evidence that supports the aforementioned treatment recommendations arises from descriptive observational studies. Traditionally, catatonia pathophysiological research focused on the study of subcortical brain structures. Currently there exists compelling evidence that supports a cortical origin of the syndrome, emphasizing the role of the prefrontal cortex. Neuropsychiatric catatonia models that integrate clinical, pathophysiological, and neurobiological findings have been postulated. The aim of the present review is to summarize up-to-date available evidence associated with the pharmacotherapeutic approach to acute catatonia as well as the neurochemical basis of its effectiveness. Likewise, general measures intended to prevent morbimortality are subject to discussion herein.

  6. Pharmacological Effects of Niacin on Acute Hyperlipemia.

    PubMed

    la Paz, Sergio Montserrat-de; Bermudez, Beatriz; Naranjo, M Carmen; Lopez, Sergio; Abia, Rocio; Muriana, Francisco J G

    2016-01-01

    The well-known changes in modern lifestyle habits including over nutrition and physical inactivity have led to striking adverse effects on public health (e.g., obesity, diabetes, and metabolic syndrome) over recent decades. One noticeable consequence is exaggerated and prolonged state of postprandial hyperlipemia due to the ingestion of multiple fat-enriched meals during the course of a day. Postprandial (non-fasting) hyperlipemia is characterized by increased blood levels of exogenous triglycerides (TG) in the form of apolipoprotein (apo) B48-containing TG-rich lipoproteins (TRL), which have a causal role in the pathogenesis and progression of cardiovascular disease (CVD). The cardiovascular benefits of lifestyle modification (healthy diet and exercise) and conventional lipid-lowering therapies (e.g., statins, fibrates, and niacin) could involve their favourable effects on postprandial metabolism. Pharmacologically, niacin has been used as an athero-protective drug for five decades. Studies have since shown that niacin may decrease fasting levels of plasma verylow- density lipoproteins (VLDL), low-density lipoprotein cholesterol (LDL-C), and lipoprotein [a] (Lp[a]), while may increase high-density lipoprotein cholesterol (HDL-C). Herein, the purpose of this review was to provide an update on effects and mechanisms related to the pharmacological actions of niacin on acute hyperlipemia.

  7. Pharmacological Inhibition of Feline Immunodeficiency Virus (FIV)

    PubMed Central

    Mohammadi, Hakimeh; Bienzle, Dorothee

    2012-01-01

    Feline immunodeficiency virus (FIV) is a member of the retroviridae family of viruses and causes an acquired immunodeficiency syndrome (AIDS) in domestic and non-domestic cats worldwide. Genome organization of FIV and clinical characteristics of the disease caused by the virus are similar to those of human immunodeficiency virus (HIV). Both viruses infect T lymphocytes, monocytes and macrophages, and their replication cycle in infected cells is analogous. Due to marked similarity in genomic organization, virus structure, virus replication and disease pathogenesis of FIV and HIV, infection of cats with FIV is a useful tool to study and develop novel drugs and vaccines for HIV. Anti-retroviral drugs studied extensively in HIV infection have targeted different steps of the virus replication cycle: (1) inhibition of virus entry into susceptible cells at the level of attachment to host cell surface receptors and co-receptors; (2) inhibition of fusion of the virus membrane with the cell membrane; (3) blockade of reverse transcription of viral genomic RNA; (4) interruption of nuclear translocation and viral DNA integration into host genomes; (5) prevention of viral transcript processing and nuclear export; and (6) inhibition of virion assembly and maturation. Despite much success of anti-retroviral therapy slowing disease progression in people, similar therapy has not been thoroughly investigated in cats. In this article we review current pharmacological approaches and novel targets for anti-lentiviral therapy, and critically assess potentially suitable applications against FIV infection in cats. PMID:22754645

  8. Pharmacological inhibition of poly(ADP-ribose) polymerase inhibits angiogenesis

    SciTech Connect

    Rajesh, Mohanraj; Mukhopadhyay, Partha; Batkai, Sandor; Godlewski, Grzegorz; Hasko, Gyoergy; Liaudet, Lucas; Pacher, Pal . E-mail: pacher@mail.nih.gov

    2006-11-17

    Poly(ADP-ribose) polymerase (PARP) is a nuclear enzyme which plays an important role in regulating cell death and cellular responses to DNA repair. Pharmacological inhibitors of PARP are being considered as treatment for cancer both in monotherapy as well as in combination with chemotherapeutic agents and radiation, and were also reported to be protective against untoward effects exerted by certain anticancer drugs. Here we show that pharmacological inhibition of PARP with 3-aminobenzamide or PJ-34 dose-dependently reduces VEGF-induced proliferation, migration, and tube formation of human umbilical vein endothelial cells in vitro. These results suggest that treatment with PARP inhibitors may exert additional benefits in various cancers and retinopathies by decreasing angiogenesis.

  9. Bromodomains: Structure, function and pharmacology of inhibition.

    PubMed

    Ferri, Elena; Petosa, Carlo; McKenna, Charles E

    2016-04-15

    Bromodomains are epigenetic readers of histone acetylation involved in chromatin remodeling and transcriptional regulation. The human proteome comprises 46 bromodomain-containing proteins with a total of 61 bromodomains, which, despite highly conserved structural features, recognize a wide array of natural peptide ligands. Over the past five years, bromodomains have attracted great interest as promising new epigenetic targets for diverse human diseases, including inflammation, cancer, and cardiovascular disease. The demonstration in 2010 that two small molecule compounds, JQ1 and I-BET762, potently inhibit proteins of the bromodomain and extra-terminal (BET) family with translational potential for cancer and inflammatory disease sparked intense efforts in academia and pharmaceutical industry to develop novel bromodomain antagonists for therapeutic applications. Several BET inhibitors are already in clinical trials for hematological malignancies, solid tumors and cardiovascular disease. Currently, the field faces the challenge of single-target selectivity, especially within the BET family, and of overcoming problems related to the development of drug resistance. At the same time, new trends in bromodomain inhibitor research are emerging, including an increased interest in non-BET bromodomains and a focus on drug synergy with established antitumor agents to improve chemotherapeutic efficacy. This review presents an updated view of the structure and function of bromodomains, traces the development of bromodomain inhibitors and their potential therapeutic applications, and surveys the current challenges and future directions of this vibrant new field in drug discovery.

  10. Pharmacological countermeasures for the acute radiation syndrome.

    PubMed

    Xiao, Mang; Whitnall, Mark H

    2009-01-01

    The acute radiation syndrome (ARS) is defined as the signs and symptoms that occur within several months after exposure to ionizing radiation (IR). This syndrome develops after total- or partial-body irradiation at a relatively high dose (above about 1 Gy in humans) and dose rate. Normal tissue injuries induced by IR differ depending on the target organ and cell type. Organs and cells with high sensitivity to radiation include the skin, the hematopoietic system, the gut, the spermatogenic cells and the vascular system. Exposure to IR causes damage to DNA, protein, and lipids in mammalian cells, as well as increased mitochondria-dependent generation of reactive oxygen species (ROS), with subsequent cell cycle checkpoint arrest, apoptosis, and stress-related responses. DNA double strand breaks (DSBs) are a primary lethal lesion induced by IR. The cellular response to damage is complex and relies on simultaneous activation of a number of signaling networks. Among these, the activation of DNA non-homologous end-joining (NHEJ) and homologous recombination (HR), and signaling pathways containing ataxia telangiectasia mutated (ATM), play important roles. The transcription factor NFkappaB has emerged as a pro-survival actor in response to IR in ATM and p53-induced protein with a death domain (PIDD) cascades. Although radiation-induced ARS has been well documented at the clinical level, and mechanistic information is accumulating, successful prophylaxis and treatment for ARS is problematic, even with the use of supportive care and growth factors. There is a pressing need to develop radiation countermeasures that can be used both in the clinic, for small-scale incidents, and outside the clinic, in mass casualty scenarios. In this review we summarize recent information on intracellular and extracellular signaling pathways relevant to radiation countermeasure research.

  11. Pharmacologic inhibition of lactate production prevents myofibroblast differentiation.

    PubMed

    Kottmann, Robert Matthew; Trawick, Emma; Judge, Jennifer L; Wahl, Lindsay A; Epa, Amali P; Owens, Kristina M; Thatcher, Thomas H; Phipps, Richard P; Sime, Patricia J

    2015-12-01

    Myofibroblasts are one of the primary cell types responsible for the accumulation of extracellular matrix in fibrosing diseases, and targeting myofibroblast differentiation is an important therapeutic strategy for the treatment of pulmonary fibrosis. Transforming growth factor-β (TGF-β) has been shown to be an important inducer of myofibroblast differentiation. We previously demonstrated that lactate dehydrogenase and its metabolic product lactic acid are important mediators of myofibroblast differentiation, via acid-induced activation of latent TGF-β. Here we explore whether pharmacologic inhibition of LDH activity can prevent TGF-β-induced myofibroblast differentiation. Primary human lung fibroblasts from healthy patients and those with pulmonary fibrosis were treated with TGF-β and or gossypol, an LDH inhibitor. Protein and RNA were analyzed for markers of myofibroblast differentiation and extracellular matrix generation. Gossypol inhibited TGF-β-induced expression of the myofibroblast marker α-smooth muscle actin (α-SMA) in a dose-dependent manner in both healthy and fibrotic human lung fibroblasts. Gossypol also inhibited expression of collagen 1, collagen 3, and fibronectin. Gossypol inhibited LDH activity, the generation of extracellular lactic acid, and the rate of extracellular acidification in a dose-dependent manner. Furthermore, gossypol inhibited TGF-β bioactivity in a dose-dependent manner. Concurrent treatment with an LDH siRNA increased the ability of gossypol to inhibit TGF-β-induced myofibroblast differentiation. Gossypol inhibits TGF-β-induced myofibroblast differentiation through inhibition of LDH, inhibition of extracellular accumulation of lactic acid, and inhibition of TGF-β bioactivity. These data support the hypothesis that pharmacologic inhibition of LDH may play an important role in the treatment of pulmonary fibrosis.

  12. Pharmacologic inhibition of lactate production prevents myofibroblast differentiation

    PubMed Central

    Kottmann, Robert Matthew; Trawick, Emma; Judge, Jennifer L.; Wahl, Lindsay A.; Epa, Amali P.; Owens, Kristina M.; Phipps, Richard P.

    2015-01-01

    Myofibroblasts are one of the primary cell types responsible for the accumulation of extracellular matrix in fibrosing diseases, and targeting myofibroblast differentiation is an important therapeutic strategy for the treatment of pulmonary fibrosis. Transforming growth factor-β (TGF-β) has been shown to be an important inducer of myofibroblast differentiation. We previously demonstrated that lactate dehydrogenase and its metabolic product lactic acid are important mediators of myofibroblast differentiation, via acid-induced activation of latent TGF-β. Here we explore whether pharmacologic inhibition of LDH activity can prevent TGF-β-induced myofibroblast differentiation. Primary human lung fibroblasts from healthy patients and those with pulmonary fibrosis were treated with TGF-β and or gossypol, an LDH inhibitor. Protein and RNA were analyzed for markers of myofibroblast differentiation and extracellular matrix generation. Gossypol inhibited TGF-β-induced expression of the myofibroblast marker α-smooth muscle actin (α-SMA) in a dose-dependent manner in both healthy and fibrotic human lung fibroblasts. Gossypol also inhibited expression of collagen 1, collagen 3, and fibronectin. Gossypol inhibited LDH activity, the generation of extracellular lactic acid, and the rate of extracellular acidification in a dose-dependent manner. Furthermore, gossypol inhibited TGF-β bioactivity in a dose-dependent manner. Concurrent treatment with an LDH siRNA increased the ability of gossypol to inhibit TGF-β-induced myofibroblast differentiation. Gossypol inhibits TGF-β-induced myofibroblast differentiation through inhibition of LDH, inhibition of extracellular accumulation of lactic acid, and inhibition of TGF-β bioactivity. These data support the hypothesis that pharmacologic inhibition of LDH may play an important role in the treatment of pulmonary fibrosis. PMID:26408551

  13. Pharmacodynamic model of sodium-glucose transporter 2 (SGLT2) inhibition: implications for quantitative translational pharmacology.

    PubMed

    Maurer, Tristan S; Ghosh, Avijit; Haddish-Berhane, Nahor; Sawant-Basak, Aarti; Boustany-Kari, Carine M; She, Li; Leininger, Michael T; Zhu, Tong; Tugnait, Meera; Yang, Xin; Kimoto, Emi; Mascitti, Vincent; Robinson, Ralph P

    2011-12-01

    Sodium-glucose co-transporter-2 (SGLT2) inhibitors are an emerging class of agents for use in the treatment of type 2 diabetes mellitus (T2DM). Inhibition of SGLT2 leads to improved glycemic control through increased urinary glucose excretion (UGE). In this study, a biologically based pharmacokinetic/pharmacodynamic (PK/PD) model of SGLT2 inhibitor-mediated UGE was developed. The derived model was used to characterize the acute PK/PD relationship of the SGLT2 inhibitor, dapagliflozin, in rats. The quantitative translational pharmacology of dapagliflozin was examined through both prospective simulation and direct modeling of mean literature data obtained for dapagliflozin in healthy subjects. Prospective simulations provided time courses of UGE that were of consistent shape to clinical observations, but were modestly biased toward under prediction. Direct modeling provided an improved characterization of the data and precise parameter estimates which were reasonably consistent with those predicted from preclinical data. Overall, these results indicate that the acute clinical pharmacology of SGLT2 inhibitors in healthy subjects can be reasonably well predicted from preclinical data through rational accounting of species differences in pharmacokinetics, physiology, and SGLT2 pharmacology. Because these data can be generated at the earliest stages of drug discovery, the proposed model is useful in the design and development of novel SGLT2 inhibitors. In addition, this model is expected to serve as a useful foundation for future efforts to understand and predict the effects of SGLT2 inhibition under chronic administration and in other patient populations.

  14. Pharmacological inhibition of FAAH activity in rodents: A promising pharmacological approach for psychological-cardiac comorbidity?

    PubMed

    Carnevali, Luca; Rivara, Silvia; Nalivaiko, Eugene; Thayer, Julian F; Vacondio, Federica; Mor, Marco; Sgoifo, Andrea

    2017-03-01

    Numerous studies have documented a link between psychological disorders and cardiac disease. Yet, no systematic attempts have been made to develop pharmacological approaches for mood and anxiety disorders that could also be beneficial for cardiac health. The endocannabinoid system has been implicated in the regulation of stress, emotional behavior and cardiovascular function. General preclinical findings indicate that the endocannabinoid anandamide modulates physiological and behavioral stress responses and may also protect the heart from arrhythmias. Moreover, recent experimental studies suggest that pharmacological enhancement of anandamide signaling via inhibition of its degrading enzyme fatty acid amide hydrolase (FAAH) exerts anxiolytic- and antidepressive-like effects and improves cardiac autonomic function and the electrical stability of the myocardium in rodent models that reproduce aspects of human psychological/cardiac comorbidity. Here we summarize and discuss such experimental findings, which might guide future preclinical studies towards a systematic evaluation of the therapeutic potential of pharmacological approaches that target FAAH activity for the treatment of the comorbidity between psychological disorders and cardiac disease.

  15. Pharmacological diversity among drugs that inhibit bone resorption.

    PubMed

    Russell, R Graham G

    2015-06-01

    Drugs that inhibit bone resorption ('anti-resorptives') continue to dominate the therapy of bone diseases characterized by enhanced bone destruction, including Paget's disease, osteoporosis and cancers. The historic use of oestrogens for osteoporosis led on to SERMs (Selective Estrogen Receptor Modulators, e.g. raloxifene and bazedoxifene). Currently the mainstay of treatment worldwide is still with bisphosphonates, as used clinically for over 40 years. The more recently introduced anti-RANK-ligand antibody, denosumab, is also very effective in reducing vertebral, non-vertebral and hip fractures. Odanacatib is the only cathepsin K inhibitor likely to be registered for clinical use. The pharmacological basis for the action of each of these drug classes is different, enabling choices to be made to ensure their optimal use in clinical practice.

  16. Pharmacologic inhibition of JAK-STAT signaling promotes hair growth.

    PubMed

    Harel, Sivan; Higgins, Claire A; Cerise, Jane E; Dai, Zhenpeng; Chen, James C; Clynes, Raphael; Christiano, Angela M

    2015-10-01

    Several forms of hair loss in humans are characterized by the inability of hair follicles to enter the growth phase (anagen) of the hair cycle after being arrested in the resting phase (telogen). Current pharmacologic therapies have been largely unsuccessful in targeting pathways that can be selectively modulated to induce entry into anagen. We show that topical treatment of mouse and human skin with small-molecule inhibitors of the Janus kinase (JAK)-signal transducer and activator of transcription (STAT) pathway results in rapid onset of anagen and subsequent hair growth. We show that JAK inhibition regulates the activation of key hair follicle populations such as the hair germ and improves the inductivity of cultured human dermal papilla cells by controlling a molecular signature enriched in intact, fully inductive dermal papillae. Our findings open new avenues for exploration of JAK-STAT inhibition for promotion of hair growth and highlight the role of this pathway in regulating the activation of hair follicle stem cells.

  17. Pharmacological inhibition of caspase-8 limits lung tumour outgrowth

    PubMed Central

    Terlizzi, Michela; Di Crescenzo, Vincenzo Giuseppe; Perillo, Giuseppe; Galderisi, Antonio; Pinto, Aldo; Sorrentino, Rosalinda

    2015-01-01

    Background and Purpose Lung cancer is one of the leading causes of cancer death worldwide. Despite advances in therapy, conventional therapy is still the main treatment and has a high risk of chemotherapy resistance. Caspase-8 is involved in cell death and is a recognized marker for poor patient prognosis. Experimental Approach To elucidate the role of caspase-8 in lung carcinoma, we used human samples of non-small cell lung cancer (NSCLC) and a mouse model of carcinogen-induced lung cancer. Key Results Healthy and cancerous NSCLC samples had similar levels of the active form of caspase-8. Similarly, lung tumour-bearing mice had high levels of the active form of caspase-8. Pharmacological inhibition of caspase-8 by z-IETD-FMK robustly reduced tumour outgrowth and this was closely associated with a reduction in the release of pro-inflammatory cytokines, IL-6, TNF-α, IL-18, IL-1α, IL-33, but not IL-1β. Furthermore, inhibition of caspase-8 reduced the recruitment of innate suppressive cells, such as myeloid-derived suppressor cells, but not of regulatory T cells to lungs of tumour-bearing mice. However, despite the well-known role of caspase-8 in cell death, the apoptotic cascade (caspase-3, caspase-9 and Bcl-2 dependent) was not active in lungs of z-IETD-treated tumour-bearing mice, but instead higher levels of the short segment of c-FLIP (c-FLIPs) were detected. Similarly, human healthy lung samples had higher levels of c-FLIPs than cancerous samples. Conclusions and Implications Our data suggest that caspase-8 is an important orchestrator of cancer-associated inflammation and the presence of short segment of c-FLIP determines whether caspase-8 induces tumour proliferation or tumour arrest/regression in the lung. PMID:25917370

  18. Medicinal Cannabis: History, Pharmacology, And Implications for the Acute Care Setting.

    PubMed

    Bridgeman, Mary Barna; Abazia, Daniel T

    2017-03-01

    The authors review the historical use of medicinal cannabis and discuss the agent's pharmacology and pharmacokinetics, select evidence on medicinal uses, and the implications of evolving regulations on the acute care hospital setting.

  19. Complement activity and pharmacological inhibition in cardiovascular disease

    PubMed Central

    Théroux, Pierre; Martel, Catherine

    2006-01-01

    While complement is the most important component of humoral autoimmunity, and inflammation plays a key role in atherosclerosis, relatively few studies have looked at complement implications in atherosclerosis and its complications. C-reactive protein is a marker of inflammation and is also involved in atherosclerosis; it activates complement and colocalizes with activated complement proteins within the infarcting myocardium and the active atherosclerotic plaques. As new agents capable of modulating complement activity are being developed, new targets for the management of atherosclerosis are emerging that are related to autoimmunity and inflammation. The present paper reviews the putative roles of the various complement activation pathways in the development of atherosclerosis, in ST segment elevation and non-ST segment elevation acute coronary syndromes, and in coronary artery bypass graft surgery. It also provides a perspective on new therapeutic interventions being developed to modulate complement activity. These interventions include the C1 esterase inhibitor, which may be consumed in some inflammatory states resulting in the loss of one of the mechanisms inhibiting activation of the classical and lectin pathways; TP10, a recombinant protein of the soluble complement receptor type 1 (sCR1) which inhibits the C3 and C5 convertases of the common pathway by binding C3b and C4b; a truncated version of the soluble complement receptor type 1 CRI lacking the C4b binding site which selectively inhibits the alternative pathway; and pexelizumab, a monoclonal antibody selectively blocking C5 to prevent the activation of the terminal pathway that is involved in excessive inflammation and autoimmune responses. PMID:16498508

  20. Pharmacologic inhibition of fatty acid oxidation sensitizes human leukemia cells to apoptosis induction

    PubMed Central

    Samudio, Ismael; Harmancey, Romain; Fiegl, Michael; Kantarjian, Hagop; Konopleva, Marina; Korchin, Borys; Kaluarachchi, Kumar; Bornmann, William; Duvvuri, Seshagiri; Taegtmeyer, Heinrich; Andreeff, Michael

    2009-01-01

    The traditional view is that cancer cells predominately produce ATP by glycolysis, rather than by oxidation of energy-providing substrates. Mitochondrial uncoupling — the continuing reduction of oxygen without ATP synthesis — has recently been shown in leukemia cells to circumvent the ability of oxygen to inhibit glycolysis, and may promote the metabolic preference for glycolysis by shifting from pyruvate oxidation to fatty acid oxidation (FAO). Here we have demonstrated that pharmacologic inhibition of FAO with etomoxir or ranolazine inhibited proliferation and sensitized human leukemia cells — cultured alone or on bone marrow stromal cells — to apoptosis induction by ABT-737, a molecule that releases proapoptotic Bcl-2 proteins such as Bak from antiapoptotic family members. Likewise, treatment with the fatty acid synthase/lipolysis inhibitor orlistat also sensitized leukemia cells to ABT-737, which supports the notion that fatty acids promote cell survival. Mechanistically, we generated evidence suggesting that FAO regulates the activity of Bak-dependent mitochondrial permeability transition. Importantly, etomoxir decreased the number of quiescent leukemia progenitor cells in approximately 50% of primary human acute myeloid leukemia samples and, when combined with either ABT-737 or cytosine arabinoside, provided substantial therapeutic benefit in a murine model of leukemia. The results support the concept of FAO inhibitors as a therapeutic strategy in hematological malignancies. PMID:20038799

  1. Pharmacologic Comparison of Clinical Neutral Endopeptidase Inhibitors in a Rat Model of Acute Secretory Diarrhea

    PubMed Central

    Prinsen, Michael J.; Oliva, Jonathan; Campbell, Mary A.; Arnett, Stacy D.; Tajfirouz, Deena; Ruminski, Peter G.; Yu, Ying; Bond, Brian R.; Ji, Yuhua; Neckermann, Georg; Choy, Robert K. M.; de Hostos, Eugenio; Meyers, Marvin J.

    2016-01-01

    Racecadotril (acetorphan) is a neutral endopeptidase (NEP) inhibitor with known antidiarrheal activity in animals and humans; however, in humans, it suffers from shortcomings that might be improved with newer drugs in this class that have progressed to the clinic for nonenteric disease indications. To identify potentially superior NEP inhibitors with immediate clinical utility for diarrhea treatment, we compared their efficacy and pharmacologic properties in a rat intestinal hypersecretion model. Racecadotril and seven other clinical-stage inhibitors of NEP were obtained or synthesized. Enzyme potency and specificity were compared using purified peptidases. Compounds were orally administered to rats before administration of castor oil to induce diarrhea. Stool weight was recorded over 4 hours. To assess other pharmacologic properties, select compounds were orally administered to normal or castor oil–treated rats, blood and tissue samples collected at multiple time points, and active compound concentrations determined by mass spectroscopy. NEP enzyme activity was measured in tissue homogenates. Three previously untested clinical NEP inhibitors delayed diarrhea onset and reduced total stool output, with little or no effect on intestinal motility assessed by the charcoal meal test. Each was shown to be a potent, highly specific inhibitor of NEP. Each exhibited greater suppression of NEP activity in intestinal and nonintestinal tissues than did racecadotril and sustained this inhibition longer. These results suggest that newer clinical-stage NEP inhibitors originally developed for other indications may be directly repositioned for treatment of acute secretory diarrhea and offer advantages over racecadotril, such as less frequent dosing and potentially improved efficacy. PMID:26907621

  2. 21 CFR 320.28 - Correlation of bioavailability with an acute pharmacological effect or clinical evidence.

    Code of Federal Regulations, 2013 CFR

    2013-04-01

    ... 21 Food and Drugs 5 2013-04-01 2013-04-01 false Correlation of bioavailability with an acute pharmacological effect or clinical evidence. 320.28 Section 320.28 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND...

  3. Acute Pharmacological DVT Prophylaxis after Spinal Cord Injury

    PubMed Central

    Thibault-Halman, Ginette; Casha, Steven

    2011-01-01

    Abstract A systematic review of the literature was performed to address pertinent clinical questions regarding deep vein thrombosis (DVT) prophylaxis in the setting of acute spinal cord injury (SCI). Deep vein thromboses are a common occurrence following SCI. Administration of low-molecular-weight heparin (LMWH) within 72 h of injury is recommended to minimize the occurrence of DVT. Furthermore, when surgical intervention is required, LMWH should be held the morning of surgery, and resumed within 24 h post-operatively. PMID:20795870

  4. Mechanical and pharmacological restraints in acute psychiatric wards--why and how are they used?

    PubMed

    Knutzen, Maria; Bjørkly, Stål; Eidhammer, Gunnar; Lorentzen, Steinar; Helen Mjøsund, Nina; Opjordsmoen, Stein; Sandvik, Leiv; Friis, Svein

    2013-08-30

    Restraint use has been reported to be common in acute psychiatry, but empirical research is scarce concerning why and how restraints are used. This study analysed data from patients' first episodes of restraint in three acute psychiatric wards during a 2-year study period. Logistic regression analyses were used to identify predictors for type and duration of restraint. The distribution of restraint categories for the 371 restrained patients was as follows: mechanical restraint, 47.2%; mechanical and pharmacological restraint together, 35.3%; and pharmacological restraint, 17.5%. The most commonly reported reason for restraint was assault (occurred or imminent). It increased the likelihood of resulting in concomitant pharmacological restraint. Female patients had shorter duration of mechanical restraint than men. Age above 49 and female gender increased the likelihood of pharmacological versus mechanical restraint, whereas being restrained due to assault weakened this association. Episodes with mechanical restraint and coinciding pharmacological restraint lasted longer than mechanical restraint used separately, and were less common among patients with a personality disorder. Diagnoses, age and reason for restraint independently increased the likelihood for being subjected to specific types of restraint. Female gender predicted type of restraint and duration of episodes.

  5. Selective Pharmacologic Inhibition of a PASTA Kinase Increases Listeria monocytogenes Susceptibility to β-Lactam Antibiotics

    PubMed Central

    Pensinger, Daniel A.; Aliota, Matthew T.; Schaenzer, Adam J.; Boldon, Kyle M.; Ansari, Israr-ul H.; Vincent, William J. B.; Knight, Benjamin; Reniere, Michelle L.; Striker, Rob

    2014-01-01

    While β-lactam antibiotics are a critical part of the antimicrobial arsenal, they are frequently compromised by various resistance mechanisms, including changes in penicillin binding proteins of the bacterial cell wall. Genetic deletion of the penicillin binding protein and serine/threonine kinase-associated protein (PASTA) kinase in methicillin-resistant Staphylococcus aureus (MRSA) has been shown to restore β-lactam susceptibility. However, the mechanism remains unclear, and whether pharmacologic inhibition would have the same effect is unknown. In this study, we found that deletion or pharmacologic inhibition of the PASTA kinase in Listeria monocytogenes by the nonselective kinase inhibitor staurosporine results in enhanced susceptibility to both aminopenicillin and cephalosporin antibiotics. Resistance to vancomycin, another class of cell wall synthesis inhibitors, or antibiotics that inhibit protein synthesis was unaffected by staurosporine treatment. Phosphorylation assays with purified kinases revealed that staurosporine selectively inhibited the PASTA kinase of L. monocytogenes (PrkA). Importantly, staurosporine did not inhibit a L. monocytogenes kinase without a PASTA domain (Lmo0618) or the PASTA kinase from MRSA (Stk1). Finally, inhibition of PrkA with a more selective kinase inhibitor, AZD5438, similarly led to sensitization of L. monocytogenes to β-lactam antibiotics. Overall, these results suggest that pharmacologic targeting of PASTA kinases can increase the efficacy of β-lactam antibiotics. PMID:24867981

  6. Effects of Pharmacological Inhibition and Genetic Deficiency of Plasminogen Activator Inhibitor-1 in Radiation-Induced Intestinal Injury

    SciTech Connect

    Abderrahmani, Rym; Francois, Agnes; Buard, Valerie; Benderitter, Marc; Sabourin, Jean-Christophe; Crandall, David L.; Milliat, Fabien

    2009-07-01

    Purpose: To investigate effects of plasminogen activator inhibitor 1 (PAI-1) genetic deficiency and pharmacological PAI-1 inhibition with PAI-039 in a mouse model of radiation-induced enteropathy. Methods and Materials: Wild-type (Wt) and PAI-1{sup -/-} knockout mice received a single dose of 19 Gy to an exteriorized localized intestinal segment. Sham and irradiated Wt mice were treated orally with 1 mg/g of PAI-039. Histological modifications were quantified using a radiation injury score. Moreover, intestinal gene expression was monitored by real-time PCR. Results: At 3 days after irradiation, PAI-039 abolished the radiation-induced increase in the plasma active form of PAI-1 and limited the radiation-induced gene expression of transforming growth factor {beta}1 (TGF-{beta}1), CTGF, PAI-1, and COL1A2. Moreover, PAI-039 conferred temporary protection against early lethality. PAI-039 treatment limited the radiation-induced increase of CTGF and PAI-1 at 2 weeks after irradiation but had no effect at 6 weeks. Radiation injuries were less severe in PAI-1{sup -/-} mice than in Wt mice, and despite the beneficial effect, 3 days after irradiation, PAI-039 had no effects on microscopic radiation injuries compared to untreated Wt mice. Conclusions: A genetic deficiency of PAI-1 is associated with amelioration of late radiation enteropathy. Pharmacological inhibition of PAI-1 by PAI-039 positively impacts the early, acute phase increase in plasma PAI-1 and the associated radiation-induced gene expression of inflammatory/extracellular matrix proteins. Since PAI-039 has been shown to inhibit the active form of PAI-1, as opposed to the complete loss of PAI-1 in the knockout animals, these data suggest that a PAI-1 inhibitor could be beneficial in treating radiation-induced tissue injury in acute settings where PAI-1 is elevated.

  7. Pharmacologic strategies to preserve renal function in acute decompensated heart failure.

    PubMed

    Kumar, Sachin; Taylor, David O

    2015-02-01

    Over a million patients get hospitalized with the diagnosis of acute decompensated heart failure which poses an insurmountable financial burden on the health care system. Heart failure alone incurs over 30 billion dollars with half the cost spent towards acute hospitalizations. Majority of the treatment strategies have focused towards decongesting patients which often comes with the cost of worsening renal function. Renal dysfunction in the setting of acute decompensated heart failure portends worse morbidity and mortality. Recently, there has been a change in the focus with shift towards therapies attempting to conserve renal function. In the past decade, we have witnessed several large randomized controlled trials testing the established as well as emerging therapies in this subset of population with mixed results. This review intends to provide a comprehensive overview of the pharmacologic therapies commonly utilized in the management of acute decompensated heart failure and the body of evidence supporting these strategies.

  8. Pharmacological inhibition of galectin-3 protects against hypertensive nephropathy.

    PubMed

    Frenay, Anne-Roos S; Yu, Lili; van der Velde, A Rogier; Vreeswijk-Baudoin, Inge; López-Andrés, Natalia; van Goor, Harry; Silljé, Herman H; Ruifrok, Willem P; de Boer, Rudolf A

    2015-03-01

    Galectin-3 activation is involved in the pathogenesis of renal damage and fibrogenesis. Limited data are available to suggest that galectin-3-targeted intervention is a potential therapeutic candidate for the prevention of chronic kidney disease. Homozygous TGR(mREN)27 (REN2) rats develop severe high blood pressure (BP) and hypertensive end-organ damage, including nephropathy and heart failure. Male REN2 rats were treated with N-acetyllactosamine [galectin-3 inhibitor (Gal3i)] for 6 wk; untreated REN2 and Sprague-Dawley rats served as controls. We measured cardiac function with echocardiogram and invasive hemodynamics before termination. BP and proteinuria were measured at baseline and at 3 and 6 wk. Plasma creatinine was determined at 6 wk. Renal damage was assessed for focal glomerular sclerosis, glomerular desmin expression, glomerular and interstitial macrophages, kidney injury molecule-1 expression, and α-smooth muscle actin expression. Inflammatory cytokines and extracellular matrix proteinases were quantified by quantitative real-time PCR. Systolic BP was higher in control REN2 rats, with no effect of Gal3i treatment. Plasma creatinine and proteinuria were significantly increased in control REN2 rats; Gal3i treatment reduced both. Renal damage (focal glomerular sclerosis, desmin, interstitial macrophages, kidney injury molecule-1, α-smooth muscle actin, collagen type I, and collagen type III) was also improved by Gal3i. All inflammatory markers (CD68, IL-68, galectin-3, and monocyte chemoattractant protein-1) were elevated in control REN2 rats and attenuated by Gal3i. Markers of extracellular matrix turnover were marginally altered in untreated REN2 rats compared with Sprague-Dawley rats. In conclusion, galectin-3 inhibition attenuated hypertensive nephropathy, as indicated by reduced proteinuria, improved renal function, and decreased renal damage. Drugs binding to galectin-3 may be therapeutic candidates for the prevention of chronic kidney disease.

  9. Effects of pharmacological and genetic disruption of CXCR4 chemokine receptor function in B-cell acute lymphoblastic leukaemia.

    PubMed

    Randhawa, Shubhchintan; Cho, Byung S; Ghosh, Dipanjan; Sivina, Mariela; Koehrer, Stefan; Müschen, Markus; Peled, Amnon; Davis, Richard E; Konopleva, Marina; Burger, Jan A

    2016-08-01

    B cell acute lymphoblastic leukaemia (B-ALL) cells express high levels of CXCR4 chemokine receptors for homing and retention within the marrow microenvironment. Bone marrow stromal cells (BMSC) secrete CXCL12, the ligand for CXCR4, and protect B-ALL cells from cytotoxic drugs. Therefore, the therapeutic use of CXCR4 antagonists has been proposed to disrupt cross talk between B-ALL cells and the protective stroma. Because CXCR4 antagonists can have activating agonistic function, we compared the genetic and pharmacological deletion of CXCR4 in B-ALL cells, using CRISPR-Cas9 gene editing and CXCR4 antagonists that are in clinical use (plerixafor, BKT140). Both genetic and pharmacological CXCR4 inhibition significantly reduced B-ALL cell migration to CXCL12 gradients and beneath BMSC, and restored drug sensitivity to dexamethasone, vincristine and cyclophosphamide. NOD/SCID/IL-2rγnull mice injected with CXCR4 gene-deleted B-ALL cells had significant delay in disease progression and superior survival when compared to control mice injected with CXCR4 wild-type B-ALL cells. These findings indicate that anti-leukaemia activity of CXCR4 antagonists is primarily due to CXCR4 inhibition, rather than agonistic activity, and corroborate that CXCR4 is an important target to overcome stroma-mediated drug resistance in B-ALL.

  10. [Pharmacology].

    PubMed

    González, José; Orero, Ana; Olmo, Vicente; Martínez, David; Prieto, José; Bahlsen, Jose Antonio; Zaragozá, Francisco; Honorato, Jesús

    2011-06-01

    Two of the main characteristics of western societies in the last fifty years have been the medicalization of the human life and the environmental degradation. The first one has forced human being to consider medicines use related to what would be rational, reasonable and well-reasoned. The second one brought us to a new ecologist conscience. In relation to the "human social system", the effects of medication can be considered very positive as a whole, particularly those related to the amazing increase of expectative and quality of life. But, along with those unquestionable beneficial effects, medicines have also caused some negative effects for other biotic and abiotic systems, such as microbian alterations and their undesirable consequences which have involved the massive use of antibiotics in medicine and veterinary, the uncontrolled elimination of millions of doses of all kind of drugs, additives and excipients, etc., as well as atmospheric contamination and degradation of forests and deep oceans which can have been caused by investigation and production of determinated drugs. In this context Pharmacology appears as a scientific discipline that studies the research (R), development (D), production (P), and utilization (U) of drugs and medical substances in relation to the environment. From a farmaecologic perspective the drugs utilization has its development in three main contexts, all of them closely related: prescription quality, farmaceutical care, and patient's active participation in his own disease and treatment.

  11. Pharmacologic inhibition of L-tyrosine degradation ameliorates cerebral dopamine deficiency in murine phenylketonuria (PKU).

    PubMed

    Harding, Cary O; Winn, Shelley R; Gibson, K Michael; Arning, Erland; Bottiglieri, Teodoro; Grompe, Markus

    2014-09-01

    Monoamine neurotransmitter deficiency has been implicated in the etiology of neuropsychiatric symptoms associated with chronic hyperphenylalaninemia in phenylketonuria (PKU). Two proposed explanations for neurotransmitter deficiency in PKU include first, that chronically elevated blood L-phenylalanine (Phe) inhibits the transport of L-tyrosine (Tyr) and L-tryptophan (Trp), the substrates for dopamine and serotonin synthesis respectively, into brain. In the second hypothesis, elevated Phe competitively inhibits brain tyrosine hydroxylase (TH) and tryptophan hydroxylase (TPH) activities, the rate limiting steps in dopamine and serotonin synthesis. Dietary supplementation with large neutral amino acids (LNAA) including Tyr and Trp has been recommended for individuals with chronically elevated blood Phe in an attempt to restore amino acid and monoamine homeostasis in brain. As a potential alternative treatment approach, we demonstrate that pharmacologic inhibition of Tyr degradation through oral administration of nitisinone (NTBC) yielded sustained increases in blood and brain Tyr, decreased blood and brain Phe, and consequently increased dopamine synthesis in a murine model of PKU. Our results suggest that Phe-mediated inhibition of TH activity is the likely mechanism of impaired dopamine synthesis in PKU. Pharmacologic inhibition of Tyr degradation may be a promising adjunct therapy for CNS monoamine neurotransmitter deficiency in hyperphenylalaninemic individuals with PKU.

  12. Pharmacological inhibition of nicotinamide phosphoribosyltransferase/visfatin enzymatic activity identifies a new inflammatory pathway linked to NAD.

    PubMed

    Busso, Nathalie; Karababa, Mahir; Nobile, Massimo; Rolaz, Aline; Van Gool, Frédéric; Galli, Mara; Leo, Oberdan; So, Alexander; De Smedt, Thibaut

    2008-05-21

    Nicotinamide phosphoribosyltransferase (NAMPT), also known as visfatin, is the rate-limiting enzyme in the salvage pathway of NAD biosynthesis from nicotinamide. Since its expression is upregulated during inflammation, NAMPT represents a novel clinical biomarker in acute lung injury, rheumatoid arthritis, and Crohn's disease. However, its role in disease progression remains unknown. We report here that NAMPT is a key player in inflammatory arthritis. Increased expression of NAMPT was confirmed in mice with collagen-induced arthritis, both in serum and in the arthritic paw. Importantly, a specific competitive inhibitor of NAMPT effectively reduced arthritis severity with comparable activity to etanercept, and decreased pro-inflammatory cytokine secretion in affected joints. Moreover, NAMPT inhibition reduced intracellular NAD concentration in inflammatory cells and circulating TNFalpha levels during endotoxemia in mice. In vitro pharmacological inhibition of NAMPT reduced the intracellular concentration of NAD and pro-inflammatory cytokine secretion by inflammatory cells. Thus, NAMPT links NAD metabolism to inflammatory cytokine secretion by leukocytes, and its inhibition might therefore have therapeutic efficacy in immune-mediated inflammatory disorders.

  13. Pharmacological Inhibition of PKCθ Counteracts Muscle Disease in a Mouse Model of Duchenne Muscular Dystrophy.

    PubMed

    Marrocco, V; Fiore, P; Benedetti, A; Pisu, S; Rizzuto, E; Musarò, A; Madaro, L; Lozanoska-Ochser, B; Bouché, M

    2017-02-01

    Inflammation plays a considerable role in the progression of Duchenne Muscular Dystrophy (DMD), a severe muscle disease caused by a mutation in the dystrophin gene. We previously showed that genetic ablation of Protein Kinase C θ (PKCθ) in mdx, the mouse model of DMD, improves muscle healing and regeneration, preventing massive inflammation. To establish whether pharmacological targeting of PKCθ in DMD can be proposed as a therapeutic option, in this study we treated young mdx mice with the PKCθ inhibitor Compound 20 (C20). We show that C20 treatment led to a significant reduction in muscle damage associated with reduced immune cells infiltration, reduced inflammatory pathways activation, and maintained muscle regeneration. Importantly, C20 treatment is efficient in recovering muscle performance in mdx mice, by preserving muscle integrity. Together, these results provide proof of principle that pharmacological inhibition of PKCθ in DMD can be considered an attractive strategy to modulate immune response and prevent the progression of the disease.

  14. Preferential pharmacological inhibition of macrophage ACAT increases plaque formation in mouse and rabbit models of atherogenesis.

    PubMed

    Perrey, S; Legendre, C; Matsuura, A; Guffroy, C; Binet, J; Ohbayashi, S; Tanaka, T; Ortuno, J C; Matsukura, T; Laugel, T; Padovani, P; Bellamy, F; Edgar, A D

    2001-04-01

    The cholesteryl ester, foam cell-enriched vulnerable plaque is a principle pharmacological target for reducing athero-thrombosis. Acyl CoA:cholesterol Acyl Transferase (ACAT) catalyzes the esterification of free cholesterol in intestine, liver, adrenal and macrophages, leading in the latter cells to intracellular cholesteryl ester accumulation and foam cell formation in the arterial intima. Previous studies suggested the existence of several isoforms of ACAT with different tissue distribution and this has largely been confirmed by molecular cloning of ACAT-1 and ACAT-2. We developed a series of ACAT inhibitors that preferentially inhibited macrophage ACAT relative to hepatic or intestinal ACAT based on in vitro assays and ex vivo bioavailability studies. Four of these compounds were tested in three models of atherosclerosis at oral doses shown to give sufficient bioavailable monocyte/macrophage ACAT inhibitory activity. In fat-fed C57BL/6 mice, chow fed apo E-/- mice and KHC rabbits, the various ACAT inhibitors had either no effect or increased indices of atherosclerotic foam cell formation. Direct and indirect measurements suggest that the increase in plaque formation may have been related to inhibition of macrophage ACAT possibly leading to cytotoxic effects due to augmented free cholesterol. These results suggest that pharmacological inhibition of macrophage ACAT may not reduce, but actually aggravate, foam cell formation and progression.

  15. Pharmacological inhibition of cystine-glutamate exchange induces endoplasmic reticulum stress and ferroptosis.

    PubMed

    Dixon, Scott J; Patel, Darpan N; Welsch, Matthew; Skouta, Rachid; Lee, Eric D; Hayano, Miki; Thomas, Ajit G; Gleason, Caroline E; Tatonetti, Nicholas P; Slusher, Barbara S; Stockwell, Brent R

    2014-05-20

    Exchange of extracellular cystine for intracellular glutamate by the antiporter system xc (-) is implicated in numerous pathologies. Pharmacological agents that inhibit system xc (-) activity with high potency have long been sought, but have remained elusive. In this study, we report that the small molecule erastin is a potent, selective inhibitor of system xc (-). RNA sequencing revealed that inhibition of cystine-glutamate exchange leads to activation of an ER stress response and upregulation of CHAC1, providing a pharmacodynamic marker for system xc (-) inhibition. We also found that the clinically approved anti-cancer drug sorafenib, but not other kinase inhibitors, inhibits system xc (-) function and can trigger ER stress and ferroptosis. In an analysis of hospital records and adverse event reports, we found that patients treated with sorafenib exhibited unique metabolic and phenotypic alterations compared to patients treated with other kinase-inhibiting drugs. Finally, using a genetic approach, we identified new genes dramatically upregulated in cells resistant to ferroptosis.DOI: http://dx.doi.org/10.7554/eLife.02523.001.

  16. Pharmacological inhibition of soluble epoxide hydrolase prevents renal interstitial fibrogenesis in obstructive nephropathy

    PubMed Central

    Kim, Jinu; Yoon, Sang Pil; Toews, Myron L.; Imig, John D.; Hwang, Sung Hee; Hammock, Bruce D.

    2014-01-01

    Treating chronic kidney disease (CKD) has been challenging because of its pathogenic complexity. Epoxyeicosatrienoic acids (EETs) are cytochrome P-450-dependent derivatives of arachidonic acid with antihypertensive, anti-inflammatory, and profibrinolytic functions. We recently reported that genetic ablation of soluble epoxide hydrolase (sEH), an enzyme that converts EETs to less active dihydroxyeicosatrienoic acids, prevents renal tubulointerstitial fibrosis and inflammation in experimental mouse models of CKD. Here, we tested the hypothesis that pharmacological inhibition of sEH after unilateral ureteral obstruction (UUO) would attenuate tubulointerstitial fibrosis and inflammation in mouse kidneys and may provide a novel approach to manage the progression of CKD. Inhibition of sEH enhanced levels of EET regioisomers and abolished tubulointerstitial fibrosis, as demonstrated by reduced collagen deposition and myofibroblast formation after UUO. The inflammatory response was also attenuated, as demonstrated by decreased influx of neutrophils and macrophages and decreased expression of inflammatory cytokines keratinocyte chemoattractant, macrophage inflammatory protein-2, monocyte chemotactic protein-1, TNF-α, and ICAM-1 in kidneys after UUO. UUO upregulated transforming growth factor-β1/Smad3 signaling and induced NF-κB activation, oxidative stress, tubular injury, and apoptosis; in contrast, it downregulated antifibrotic factors, including peroxisome proliferator-activated receptor (PPAR) isoforms, especially PPAR-γ. sEH inhibition mitigated the aforementioned malevolent effects in UUO kidneys. These data demonstrate that pharmacological inhibition of sEH promotes anti-inflammatory and fibroprotective effects in UUO kidneys by preventing tubular injury, downregulation of NF-κB, transforming growth factor-β1/Smad3, and inflammatory signaling pathways, and activation of PPAR isoforms. Our data suggest the potential use of sEH inhibitors in treating fibrogenesis

  17. Tissue Pharmacology of Da-Cheng-Qi Decoction in Experimental Acute Pancreatitis in Rats

    PubMed Central

    Zhao, Xianlin; Zhang, Yumei; Li, Juan; Wan, Meihua; Zhu, Shifeng; Guo, Hui; Xiang, Jin; Thrower, Edwin C.; Tang, Wenfu

    2015-01-01

    Objectives. The Chinese herbal medicine Da-Cheng-Qi Decoction (DCQD) can ameliorate the severity of acute pancreatitis (AP). However, the potential pharmacological mechanism remains unclear. This study explored the potential effective components and the pharmacokinetic characteristics of DCQD in target tissue in experimental acute pancreatitis in rats. Methods. Acute pancreatitis-like symptoms were first induced in rats and then they were given different doses of DCQD (6 g/kg, 12 g/kg, and 24 g/kg body weight) orally. Tissue drug concentration, tissue pathological score, and inflammatory mediators in pancreas, intestine, and lung tissues of rats were examined after 24 hours, respectively. Results. Major components of DCQD could be found in target tissues and their concentrations increased in conjunction with the intake dose of DCQD. The high-dose compounds showed maximal effect on altering levels of anti-inflammatory (interleukin-4 and interleukin-10) and proinflammatory markers (tumor necrosis factor α and interleukin-6) and ameliorating the pathological damage in target tissues (P < 0.05). Conclusions. DCQD could alleviate pancreatic, intestinal, and lung injury by altering levels of inflammatory cytokines in AP rats with tissue distribution of its components. PMID:26199633

  18. Leucine-rich Repeat Kinase 2 (LRRK2) Pharmacological Inhibition Abates α-Synuclein Gene-induced Neurodegeneration.

    PubMed

    Daher, João P L; Abdelmotilib, Hisham A; Hu, Xianzhen; Volpicelli-Daley, Laura A; Moehle, Mark S; Fraser, Kyle B; Needle, Elie; Chen, Yi; Steyn, Stefanus J; Galatsis, Paul; Hirst, Warren D; West, Andrew B

    2015-08-07

    Therapeutic approaches to slow or block the progression of Parkinson disease (PD) do not exist. Genetic and biochemical studies implicate α-synuclein and leucine-rich repeat kinase 2 (LRRK2) in late-onset PD. LRRK2 kinase activity has been linked to neurodegenerative pathways. However, the therapeutic potential of LRRK2 kinase inhibitors is not clear because significant toxicities have been associated with one class of LRRK2 kinase inhibitors. Furthermore, LRRK2 kinase inhibitors have not been tested previously for efficacy in models of α-synuclein-induced neurodegeneration. To better understand the therapeutic potential of LRRK2 kinase inhibition in PD, we evaluated the tolerability and efficacy of a LRRK2 kinase inhibitor, PF-06447475, in preventing α-synuclein-induced neurodegeneration in rats. Both wild-type rats as well as transgenic G2019S-LRRK2 rats were injected intracranially with adeno-associated viral vectors expressing human α-synuclein in the substantia nigra. Rats were treated with PF-06447475 or a control compound for 4 weeks post-viral transduction. We found that rats expressing G2019S-LRRK2 have exacerbated dopaminergic neurodegeneration and inflammation in response to the overexpression of α-synuclein. Both neurodegeneration and neuroinflammation associated with G2019S-LRRK2 expression were mitigated by LRRK2 kinase inhibition. Furthermore, PF-06447475 provided neuroprotection in wild-type rats. We could not detect adverse pathological indications in the lung, kidney, or liver of rats treated with PF-06447475. These results demonstrate that pharmacological inhibition of LRRK2 is well tolerated for a 4-week period of time in rats and can counteract dopaminergic neurodegeneration caused by acute α-synuclein overexpression.

  19. Influence of gender and sex hormones on nicotine acute pharmacological effects in mice.

    PubMed

    Damaj, M I

    2001-01-01

    The present study conducted a comprehensive examination of the putative sex differences in the potency of nicotine between male and female ICR mice using several pharmacological and behavioral tests. Among the responses to nicotine where significant sex differences were observed are the antinociceptive and the anxiolytic effects of nicotine. Female mice were found less sensitive to the acute effects of nicotine in these tests after s.c. administration. Similar gender differences were found after i.t. injection. Influence of gonadal hormones could underlie sex differences observed in our studies. Indeed, our data clearly indicate that sex hormones can modulate the effects of nicotine and nicotinic receptors in a differential manner. Progesterone and 17beta-estradiol were found to block nicotine's antinociception in mice. Testosterone failed to do so. In addition, progesterone and 17beta-estradiol blocked nicotine activation of alpha(4)beta(2) neuronal acetylcholine nicotinic receptors expressed in oocytes. Our findings contribute to our search for receptor mechanisms in drug dependence and in the discovery of better pharmacological agents for nicotine dependence.

  20. Efficacy and harm of pharmacological prevention of acute mountain sickness: quantitative systematic review

    PubMed Central

    Dumont, Lionel; Mardirosoff, Chahé; Tramèr, Martin R

    2000-01-01

    Objective To quantify efficacy and harm of pharmacological prevention of acute mountain sickness. Data sources Systematic search (Medline, Embase, Cochrane Library, internet, bibliographies, authors) in any language, up to October 1999. Study selection Randomised placebo controlled trials. Data extraction Dichotomous data on efficacy and harm from 33 trials (523 subjects received 13 different interventions, 519 a placebo). Data synthesis At above 4000 m the mean incidence of acute mountain sickness with placebo was 67% (range 25% to 100%); incidence depended on the rate of ascent, but not on the altitude or the mode of ascent. Across all ascent rates, dexamethasone 8-16 mg prevented acute mountain sickness (relative risk 2.50 (95% confidence interval 1.71 to 3.66); number needed to treat (NNT) 2.8 (2.0 to 4.6)), without evidence of dose responsiveness. Acetazolamide 750 mg was also efficacious (2.18 (1.52 to 3.15); NNT 2.9 (2.0 to 5.2)), but 500 mg was not. In two trials, adverse reaction (including depression) occurred after dexamethasone was stopped abruptly (4.45 (1.08 to 18); NNT 3.7 (2.5 to 6.9)). With acetazolamide, paraesthesia (4.02 (1.71 to 9.43); NNT 3.0 (2.0 to 6.0)) and polyuria (4.24 (1.92 to 9.37); NNT 3.6 (2.5 to 6.2)) were reported. Data were sparse on nifedipine, frusemide (furosemide), dihydroxyaluminium-sodium, spironolactone, phenytoin, codeine, phenformin, antidiuretic hormone, and ginkgo biloba. Conclusions At above 4000 m, with a high ascent rate, fewer than three subjects need to be treated with prophylactic dexamethasone 8-16 mg or acetazolamide 750 mg for one subject not to experience acute mountain sickness who would have done so had they all received a placebo. Acetazolamide 500 mg does not work. PMID:10915127

  1. Eupafolin nanoparticle improves acute renal injury induced by LPS through inhibiting ROS and inflammation.

    PubMed

    Zhang, Hao; Chen, Ming-Kun; Li, Ke; Hu, Cheng; Lu, Min-Hua; Situ, Jie

    2017-01-01

    Acute renal injury is a common severe clinical syndrome, occurring in many clinical situations. It is necessary to explore effective drugs to treat it. Eupafolin is a flavonoid compound, derived from Phyla nodiflora, which has been previously reported to possess a variety of pharmacological activities, including anti-inflammatory and antioxidant effects. However, it is known little about how it works in acute renal injury. Also, eupafolin is characterized by skin penetration and poor water solubility, limiting its clinical applications. Thus, we synthesized an eupafolin nanoparticle delivery system. We found that eupafolin nanoparticle could address the physicochemical defects of raw eupafolin and increase water solubility without any toxicity to normal renal cells via reducing particle size. Eupafolin nanoparticle attenuated LPS-induced acute renal injury in mice through inhibiting oxidative stress and inflammation accompanied with up-regulated SOD activity and down-regulated pro-inflammatory cytokines. Additionally, inactivation of NF-κB and MAPKs of p38, ERK1/2 and JNK signaling pathways was a main molecular mechanism by which eupafolin nanoparticle improved renal injury. Together, eupafolin nanoparticle exhibits effective anti-oxidant and anti-inflammatory activities, which could be used as a potential drug to ameliorate acute renal injury clinically.

  2. Consistent sex-dependent effects of PKMζ gene ablation and pharmacological inhibition on the maintenance of referred pain

    PubMed Central

    Nasir, Hibatulnaseer; Mahboubi, Hicham; Gyawali, Sandeep; Ding, Stephanie; Mickeviciute, Aiste; Ragavendran, J Vaigunda; Laferrière, André; Stochaj, Ursula

    2016-01-01

    Background Persistently active PKMζ has been implicated in maintaining spinal nociceptive sensitization that underlies pain hypersensitivity. However, evidence for PKMζ in the maintenance of pain hypersensitivity comes exclusively from short-term studies in males using pharmacological agents of questionable selectivity. The present study examines the contribution of PKMζ to long-lasting allodynia associated with neuropathic, inflammatory, or referred visceral and muscle pain in males and females using pharmacological inhibition or genetic ablation. Results Pharmacological inhibition or genetic ablation of PKMζ reduced mild formalin pain and slowly developing contralateral allodynia in nerve-injured rats, but not moderate formalin pain or ipsilateral allodynia in models of neuropathic and inflammatory pain. Pharmacological inhibition or genetic ablation of PKMζ also effectively reduced referred visceral and muscle pain in male, but not in female mice and rats. Conclusion We show pharmacological inhibition and genetic ablation of PKMζ consistently attenuate long-lasting pain hypersensitivity. However, differential effects in models of referred versus inflammatory and neuropathic pain, and in males versus females, highlight the roles of afferent input-dependent masking and sex differences in the maintenance of pain hypersensitivity. PMID:27899695

  3. Monochloramine induces acute and protracted colitis in the rat: response to pharmacological treatment.

    PubMed

    Ballester, Isabel; González, Raquel; Nieto, Ana; Zarzuelo, Antonio; de Medina, Fermín Sánchez

    2005-05-06

    Monochloramine is a powerful oxidative molecule that is produced in inflammatory sites. We investigated the effect of intrarectally administered monochloramine (3.2 mg) in the rat. A single enema induced after 24 h an intense inflammatory reaction characterized by mucosal necrosis, submucosal edema, hemorrhage and colonic thickening, as well as induction of nitric oxide synthase and tumor necrosis factor and an increase in the interferon gamma/interleukin 4 ratio. The inflammatory response peaked 3-5 days after monochloramine administration and then followed a extended recovery phase. At 1 week there was substantial but incomplete mucosal repair, submucosal edema, neutrophil/macrophage infiltration and increased myeloperoxydase and alkaline phosphatase activities. Oxidative stress, as determined by malonyldialdehyde levels, was prominent only in the acute phase (3-5 days). Monochloramine colitis was amenable to pharmacological treatment with sulphasalazine or prednisolone, suggesting that it may be used as an experimental model of inflammatory bowel disease. In conclusion, monochloramine induces acute and protracted colonic inflammation in the rat. Locally produced monochloramine might contribute to the perpetuation of inflammatory bowel disease.

  4. Pharmacologic inhibition of reactive gliosis blocks TNF-α-mediated neuronal apoptosis

    PubMed Central

    Livne-Bar, Izhar; Lam, Susy; Chan, Darren; Guo, Xiaoxin; Askar, Idil; Nahirnyj, Adrian; Flanagan, John G; Sivak, Jeremy M

    2016-01-01

    Reactive gliosis is an early pathological feature common to most neurodegenerative diseases, yet its regulation and impact remain poorly understood. Normally astrocytes maintain a critical homeostatic balance. After stress or injury they undergo rapid parainflammatory activation, characterized by hypertrophy, and increased polymerization of type III intermediate filaments (IFs), particularly glial fibrillary acidic protein and vimentin. However, the consequences of IF dynamics in the adult CNS remains unclear, and no pharmacologic tools have been available to target this mechanism in vivo. The mammalian retina is an accessible model to study the regulation of astrocyte stress responses, and their influence on retinal neuronal homeostasis. In particular, our work and others have implicated p38 mitogen-activated protein kinase (MAPK) signaling as a key regulator of glutamate recycling, antioxidant activity and cytokine secretion by astrocytes and related Müller glia, with potent influences on neighboring neurons. Here we report experiments with the small molecule inhibitor, withaferin A (WFA), to specifically block type III IF dynamics in vivo. WFA was administered in a model of metabolic retinal injury induced by kainic acid, and in combination with a recent model of debridement-induced astrocyte reactivity. We show that WFA specifically targets IFs and reduces astrocyte and Müller glial reactivity in vivo. Inhibition of glial IF polymerization blocked p38 MAPK-dependent secretion of TNF-α, resulting in markedly reduced neuronal apoptosis. To our knowledge this is the first study to demonstrate that pharmacologic inhibition of IF dynamics in reactive glia protects neurons in vivo. PMID:27685630

  5. Genetic and Pharmacologic Inhibition of the Chemokine Receptor CXCR2 Prevents Experimental Hypertension and Vascular Dysfunction

    PubMed Central

    Wang, Lei; Zhao, Xue-Chen; Cui, Wei; Ma, Yong-Qiang; Ren, Hua-Liang; Zhou, Xin; Fassett, John; Yang, Yan-Zong; Chen, Yingjie; Xia, Yun-Long; Du, Jie

    2016-01-01

    Background: The recruitment of leukocytes to the vascular wall is a key step in hypertension development. Chemokine receptor CXCR2 mediates inflammatory cell chemotaxis in several diseases. However, the role of CXCR2 in hypertension development and the underlying mechanisms remain unknown. Methods: Angiotensin II (490 ng·kg-1·min-1) or deoxycorticosterone acetate (DOCA) salt–induced mouse hypertensive models in genetic ablation, pharmacologic inhibition of CXCR2, and adoptive bone marrow transfer mice were used to determine the role of CXCR2 in hypertension (measured by radiotelemetry and tail-cuff system), inflammation (verified by flow cytometry and quantitative real-time polymerase chain reaction [PCR] analysis), vascular remodeling (studied by haematoxylin and eosin and Masson’s trichrome staining), vascular dysfunction (assessed by aortic ring), and oxidative stress (indicated by nicotinamide adenine dinucleotide phosphate [NADPH] oxidase activity, dihydroethidium staining, and quantitative real-time PCR analysis). Moreover, the blood CXCR2+ cells in normotensive controls and hypertension patients were analyzed by flow cytometry. Results: Angiotensin II significantly upregulated the expression of CXCR2 mRNA and protein and increased the number of CD45+ CXCR2+ cells in mouse aorta (n=8 per group). Selective CXCR2 knockout (CXCR2-/-) or pharmacological inhibition of CXCR2 markedly reduced angiotensin II- or DOCA-salt-induced blood pressure elevation, aortic thickness and collagen deposition, accumulation of proinflammatory cells into the vascular wall, and expression of cytokines (n=8 per group). CXCR2 inhibition also ameliorated angiotensin II-induced vascular dysfunction and reduced vascular superoxide formation, NADPH activity, and expression of NADPH oxidase subunits (n=6 per group). Bone marrow reconstitution of wild-type mice with CXCR2-/- bone marrow cells also significantly abolished angiotensin II-induced responses (n=6 per group). It is important

  6. Optogenetic and pharmacologic dissection of feedforward inhibition in Drosophila motion vision.

    PubMed

    Mauss, Alex S; Meier, Matthias; Serbe, Etienne; Borst, Alexander

    2014-02-05

    Visual systems extract directional motion information from spatiotemporal luminance changes on the retina. An algorithmic model, the Reichardt detector, accounts for this by multiplying adjacent inputs after asymmetric temporal filtering. The outputs of two mirror-symmetrical units tuned to opposite directions are thought to be subtracted on the dendrites of wide-field motion-sensitive lobula plate tangential cells by antagonistic transmitter systems. In Drosophila, small-field T4/T5 cells carry visual motion information to the tangential cells that are depolarized during preferred and hyperpolarized during null direction motion. While preferred direction input is likely provided by excitation from T4/T5 terminals, the origin of null direction inhibition is unclear. Probing the connectivity between T4/T5 and tangential cells in Drosophila using a combination of optogenetics, electrophysiology, and pharmacology, we found a direct excitatory as well as an indirect inhibitory component. This suggests that the null direction response is caused by feedforward inhibition via yet unidentified neurons.

  7. Generating a "Humanized" Drosophila S2 Cell Line Sensitive to Pharmacological Inhibition of Kinesin-5.

    PubMed

    Ye, Anna A; Maresca, Thomas J

    2016-01-20

    Kinetochores are large protein-based structures that assemble on centromeres during cell division and link chromosomes to spindle microtubules. Proper distribution of the genetic material requires that sister kinetochores on every chromosome become bioriented by attaching to microtubules from opposite spindle poles before progressing into anaphase. However, erroneous, non-bioriented attachment states are common and cellular pathways exist to both detect and correct such attachments during cell division. The process by which improper kinetochore-microtubule interactions are destabilized is referred to as error correction. To study error correction in living cells, incorrect attachments are purposely generated via chemical inhibition of kinesin-5 motor, which leads to monopolar spindle assembly, and the transition from mal-orientation to biorientation is observed following drug washout. The large number of chromosomes in many model tissue culture cell types poses a challenge in observing individual error correction events. Drosophila S2 cells are better subjects for such studies as they possess as few as 4 pairs of chromosomes. However, small molecule kinesin-5 inhibitors are ineffective against Drosophila kinesin-5 (Klp61F). Here we describe how to build a Drosophila cell line that effectively replaces Klp61F with human kinesin-5, which renders the cells sensitive to pharmacological inhibition of the motor and suitable for use in the cell-based error correction assay.

  8. Genetic and pharmacological inhibition of vanin-1 activity in animal models of type 2 diabetes

    PubMed Central

    van Diepen, Janna A.; Jansen, Patrick A.; Ballak, Dov B.; Hijmans, Anneke; Rutjes, Floris P.J.T.; Tack, Cees J.; Netea, Mihai G.; Schalkwijk, Joost; Stienstra, Rinke

    2016-01-01

    Vanins are enzymes that convert pantetheine to pantothenic acid (vitamin B5). Insights into the function of vanins have evolved lately, indicating vanin-1 to play a role in inflammation, oxidative stress and cell migration. Moreover, vanin-1 has recently gained attention as a novel modulator of hepatic glucose and lipid metabolism. In the present study, we investigated the role of vanin-1 in the development of hepatic steatosis and insulin resistance in animal models of obesity and diabetes. In addition, we evaluated the potency of RR6, a novel pharmacological vanin-1 inhibitor, as an anti-diabetic drug. Increased vanin activity was observed in plasma and liver of high fat diet (HFD)-induced obese mice, as well as ZDF-diabetic rats. Ablation of vanin-1 (Vnn1−/− mice) mildly improved glucose tolerance and insulin sensitivity in HFD-fed mice, but had no effects on body weight, hepatic steatosis or circulating lipid levels. Oral administration of RR6 for 8 days completely inhibited plasma vanin activity, but did not affect hepatic glucose production, insulin sensitivity or hepatic steatosis in ZDF-diabetes rats. In conclusion, absence of vanin-1 activity improves insulin sensitivity in HFD-fed animals, yet short-term inhibition of vanin activity may have limited value as an anti-diabetic strategy. PMID:26932716

  9. Targeting glutaminolysis has antileukemic activity in acute myeloid leukemia and synergizes with BCL-2 inhibition.

    PubMed

    Jacque, Nathalie; Ronchetti, Anne Marie; Larrue, Clément; Meunier, Godelieve; Birsen, Rudy; Willems, Lise; Saland, Estelle; Decroocq, Justine; Maciel, Thiago Trovati; Lambert, Mireille; Poulain, Laury; Hospital, Marie Anne; Sujobert, Pierre; Joseph, Laure; Chapuis, Nicolas; Lacombe, Catherine; Moura, Ivan Cruz; Demo, Susan; Sarry, Jean Emmanuel; Recher, Christian; Mayeux, Patrick; Tamburini, Jérôme; Bouscary, Didier

    2015-09-10

    Cancer cells require glutamine to adapt to increased biosynthetic activity. The limiting step in intracellular glutamine catabolism involves its conversion to glutamate by glutaminase (GA). Different GA isoforms are encoded by the genes GLS1 and GLS2 in humans. Herein, we show that glutamine levels control mitochondrial oxidative phosphorylation (OXPHOS) in acute myeloid leukemia (AML) cells. Glutaminase C (GAC) is the GA isoform that is most abundantly expressed in AML. Both knockdown of GLS1 expression and pharmacologic GLS1 inhibition by the drug CB-839 can reduce OXPHOS, leading to leukemic cell proliferation arrest and apoptosis without causing cytotoxic activity against normal human CD34(+) progenitors. Strikingly, GLS1 knockdown dramatically inhibited AML development in NSG mice. The antileukemic activity of CB-839 was abrogated by both the expression of a hyperactive GAC(K320A) allele and the addition of the tricarboxyclic acid cycle product α-ketoglutarate, indicating the critical function of GLS1 in AML cell survival. Finally, glutaminolysis inhibition activated mitochondrial apoptosis and synergistically sensitized leukemic cells to priming with the BCL-2 inhibitor ABT-199. These findings show that targeting glutamine addiction via GLS1 inhibition offers a potential novel therapeutic strategy for AML.

  10. [Pharmacological analysis of the pathogenesis of acute poisoning with the synthetic pyrethroid cypermethrin using the hydrobiont Daphnia magna Straus].

    PubMed

    Podosinovikova, N P; Solov'eva, N E; Mukovskiĭ, L A; Petrov, V V; Matveev, B B; Dolgo-Saburov, V B

    2002-01-01

    The results of pharmacological analysis are presented which provide information on the pathogenesis of acute cypermethrin poisoning that involves disturbances in various systems of the organism. These include changes in the system of excitatory amino acids (EAAs) and violation of the free radical generation processes, Na + channel functioning, cholinergic transmission, etc. The screening of drugs belonging to various pharmacological groups influencing the toxicity of pyrethroids (EAA receptor antagonists, antioxidants, Na + channel blockers, M-cholinoreceptor blockers) revealed promising agents for the treatment of cypermethrin poisoning.

  11. Striatal-enriched protein tyrosine phosphatase modulates nociception: evidence from genetic deletion and pharmacological inhibition

    PubMed Central

    Azkona, Garikoitz; Saavedra, Ana; Aira, Zigor; Aluja, David; Xifró, Xavier; Baguley, Tyler; Alberch, Jordi; Ellman, Jonathan A.; Lombroso, Paul J.; Azkue, Jon J.; Pérez-Navarro, Esther

    2016-01-01

    The information from nociceptors is processed in the dorsal horn of the spinal cord by complex circuits involving excitatory and inhibitory interneurons. It is well documented that GluN2B and ERK1/2 phosphorylation contributes to central sensitization. Striatal-enriched protein tyrosine phosphatase (STEP) dephosphorylates GluN2B and ERK1/2, promoting internalization of GluN2B and inactivation of ERK1/2. The activity of STEP was modulated by genetic (STEP knockout mice) and pharmacological (recently synthesized STEP inhibitor, TC-2153) approaches. STEP61 protein levels in the lumbar spinal cord were determined in male and female mice of different ages. Inflammatory pain was induced by complete Freund’s adjuvant injection. Behavioral tests, immunoblotting, and electrophysiology were used to analyze the effect of STEP on nociception. Our results show that both genetic deletion and pharmacological inhibition of STEP induced thermal hyperalgesia and mechanical allodynia, which were accompanied by increased pGluN2BTyr1472 and pERK1/2Thr202/Tyr204 levels in the lumbar spinal cord. Striatal-enriched protein tyrosine phosphatase heterozygous and knockout mice presented a similar phenotype. Furthermore, electrophysiological experiments showed that TC-2153 increased C fiber-evoked spinal field potentials. Interestingly, we found that STEP61 protein levels in the lumbar spinal cord inversely correlated with thermal hyperalgesia associated with age and female gender in mice. Consistently, STEP knockout mice failed to show age-related thermal hyperalgesia, although gender-related differences were preserved. Moreover, in a model of inflammatory pain, hyperalgesia was associated with increased phosphorylation-mediated STEP61 inactivation and increased pGluN2BTyr1472 and pERK1/2Thr202/Tyr204 levels in the lumbar spinal cord. Collectively, the present results underscore an important role of spinal STEP activity in the modulation of nociception. PMID:26270590

  12. Striatal-enriched protein tyrosine phosphatase modulates nociception: evidence from genetic deletion and pharmacological inhibition.

    PubMed

    Azkona, Garikoitz; Saavedra, Ana; Aira, Zigor; Aluja, David; Xifró, Xavier; Baguley, Tyler; Alberch, Jordi; Ellman, Jonathan A; Lombroso, Paul J; Azkue, Jon J; Pérez-Navarro, Esther

    2016-02-01

    The information from nociceptors is processed in the dorsal horn of the spinal cord by complex circuits involving excitatory and inhibitory interneurons. It is well documented that GluN2B and ERK1/2 phosphorylation contributes to central sensitization. Striatal-enriched protein tyrosine phosphatase (STEP) dephosphorylates GluN2B and ERK1/2, promoting internalization of GluN2B and inactivation of ERK1/2. The activity of STEP was modulated by genetic (STEP knockout mice) and pharmacological (recently synthesized STEP inhibitor, TC-2153) approaches. STEP(61) protein levels in the lumbar spinal cord were determined in male and female mice of different ages. Inflammatory pain was induced by complete Freund's adjuvant injection. Behavioral tests, immunoblotting, and electrophysiology were used to analyze the effect of STEP on nociception. Our results show that both genetic deletion and pharmacological inhibition of STEP induced thermal hyperalgesia and mechanical allodynia, which were accompanied by increased pGluN2B(Tyr1472) and pERK1/2(Thr202/Tyr204)levels in the lumbar spinal cord. Striatal-enriched protein tyrosine phosphatase heterozygous and knockout mice presented a similar phenotype. Furthermore, electrophysiological experiments showed that TC-2153 increased C fiber-evoked spinal field potentials. Interestingly, we found that STEP(61) protein levels in the lumbar spinal cord inversely correlated with thermal hyperalgesia associated with age and female gender in mice. Consistently, STEP knockout mice failed to show age-related thermal hyperalgesia, although gender-related differences were preserved. Moreover, in a model of inflammatory pain, hyperalgesia was associated with increased phosphorylation-mediated STEP(61) inactivation and increased pGluN2B(Tyr1472) and pERK1/2(Thr202/Tyr204)levels in the lumbar spinal cord. Collectively, the present results underscore an important role of spinal STEP activity in the modulation of nociception.

  13. Genetic and pharmacological inhibition of calcineurin corrects the BDNF transport defect in Huntington's disease

    PubMed Central

    Pineda, Jose R; Pardo, Raúl; Zala, Diana; Yu, Hua; Humbert, Sandrine; Saudou, Frédéric

    2009-01-01

    Background Huntington's disease (HD) is an inherited neurogenerative disease caused by an abnormal expansion of glutamine repeats in the huntingtin protein. There is currently no treatment to prevent the neurodegeneration caused by this devastating disorder. Huntingtin has been shown to be a positive regulator of vesicular transport, particularly for neurotrophins such as brain-derived neurotrophic factor (BDNF). This function is lost in patients with HD, resulting in a decrease in neurotrophic support and subsequent neuronal death. One promising line of treatment is therefore the restoration of huntingtin function in BDNF transport. Results The phosphorylation of huntingtin at serine 421 (S421) restores its function in axonal transport. We therefore investigated whether inhibition of calcineurin, the bona fide huntingtin S421 phosphatase, restored the transport defects observed in HD. We found that pharmacological inhibition of calcineurin by FK506 led to sustained phosphorylation of mutant huntingtin at S421. FK506 restored BDNF transport in two complementary models: rat primary neuronal cultures expressing mutant huntingtin and mouse cortical neurons from HdhQ111/Q111 HD knock-in mice. This effect was the result of specific calcineurin inhibition, as calcineurin silencing restored both anterograde and retrograde transport in neurons from HdhQ111/Q111 mice. We also observed a specific increase in calcineurin activity in the brain of HdhQ111/Q111 mice potentially accounting for the selective loss of huntingtin phosphorylation and contributing to neuronal cell death in HD. Conclusion Our results validate calcineurin as a target for the treatment of HD and provide the first demonstration of the restoration of huntingtin function by an FDA-approved compound. PMID:19860865

  14. Pharmacological inhibition of PPARγ increases osteoblastogenesis and bone mass in male C57BL/6 mice.

    PubMed

    Duque, Gustavo; Li, Wei; Vidal, Christopher; Bermeo, Sandra; Rivas, Daniel; Henderson, Janet

    2013-03-01

    Infiltration of bone marrow with fat is a prevalent feature in people with age-related bone loss and osteoporosis, which correlates inversely with bone formation and positively with high expression levels of peroxisomal proliferator-activated receptor gamma (PPARγ). Inhibition of PPARγ thus represents a potential therapeutic approach for age-related bone loss. In this study, we examined the effect of PPARγ inhibition on bone in skeletally mature C57BL/6 male mice. Nine-month-old mice were treated with a PPARγ antagonist, bisphenol-A-diglycidyl ether (BADGE), alone or in combination with active vitamin D (1,25[OH](2) D(3) ) for 6 weeks. Micro-computed tomography and bone histomorphometry indicated that mice treated with either BADGE or BADGE + 1,25(OH)(2) D(3) had significantly increased bone volume and improved bone quality compared with vehicle-treated mice. This phenotype occurred in the absence of alterations in osteoclast number. Furthermore, the BADGE + 1,25(OH)(2) D(3) -treated mice exhibited higher levels of unmineralized osteoid. All of the treated groups showed a significant increase in circulating levels of bone formation markers without changes in bone resorption markers, while blood glucose, parathyroid hormone, and Ca(+) remained normal. Furthermore, treatment with BADGE induced higher levels of expression of vitamin D receptor within the bone marrow. Overall, treated mice showed higher levels of osteoblastogenesis and bone formation concomitant with decreased marrow adiposity and ex vivo adipogenesis. Taken together, these observations demonstrate that pharmacological inhibition of PPARγ may represent an effective anabolic therapy for osteoporosis in the near future.

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

    PubMed

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

    2016-03-01

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

  16. Alpinetin inhibits lipopolysaccharide-induced acute kidney injury in mice.

    PubMed

    Huang, Yi; Zhou, Li-shan; Yan, Li; Ren, Juan; Zhou, Dai-xing; Li, Shu-Sheng

    2015-10-01

    Alpinetin, a novel plant flavonoid isolated from Alpinia katsumadai Hayata, has been demonstrated to have anti-inflammatory and antioxidant effects. However, the effects of alpinetin on lipopolysaccharide (LPS)-induced acute kidney injury have not been reported. In the present study, we investigated the protective effects and the underlying mechanism of alpinetin against LPS-induced acute kidney injury in mice. The results showed that alpinetin inhibited LPS-induced kidney histopathologic changes, blood urea nitrogen (BUN) and creatinine levels. Alpinetin also inhibited LPS-induced ROS, MDA, and inflammatory cytokines TNF-α, IL-6 and IL-1β production in kidney tissues. Meanwhile, Western blot analysis showed that alpinetin suppressed LPS-induced TLR4 expression and NF-κB activation in kidney tissues. In addition, alpinetin was found to up-regulate the expression of Nrf2 and HO-1 in a dose-dependent manner. In conclusion, alpinetin protected LPS-induced kidney injury through activating Nrf2 and inhibiting TLR4 expression.

  17. The pharmacology of neurotrophic treatment with Cerebrolysin: brain protection and repair to counteract pathologies of acute and chronic neurological disorders.

    PubMed

    Masliah, E; Díez-Tejedor, E

    2012-04-01

    Neurotrophic factors are considered as part of the therapeutic strategy for neurological disorders like dementia, stroke and traumatic brain injury. Cerebrolysin is a neuropeptide preparation which mimics the action of endogenous neurotrophic factors on brain protection and repair. In dementia models, Cerebrolysin decreases β-amyloid deposition and microtubule-associated protein tau phosphorylation by regulating glycogen synthase kinase-3β and cyclin-dependent kinase 5 activity, increases synaptic density and restores neuronal cytoarchitecture. These effects protect integrity of the neuronal circuits and thus result in improved cognitive and behavioral performance. Furthermore, Cerebrolysin enhances neurogenesis in the dentate gyrus, the basis for neuronal replacement therapy in neurodegenerative diseases. Experimental studies in stroke animal models have shown that Cerebrolysin stabilizes the structural integrity of cells by inhibition of calpain and reduces the number of apoptotic cells after ischemic lesion. Cerebrolysin induces restorative processes, decreases infarct volume and edema formation and promotes functional recovery. Stroke-induced neurogenesis in the subventricular zone was also promoted by Cerebrolysin, thus supporting the brain's self-repair after stroke. Both, traumatic brain and spinal cord injury conditions stimulate the expression of natural neurotrophic factors to promote repair and regeneration processes -axonal regeneration, neuronal plasticity and neurogenesis- that is considered to be crucial for the future recovery. Neuroprotective effects of Cerebrolysin on experimentally induced traumatic spinal cord injury have shown that Cerebrolysin prevents apoptosis of lesioned motoneurons and promotes functional recovery. This section summarizes the most relevant data on the pharmacology of Cerebrolysin obtained from in vitro assays (biochemical and cell cultures) and in vivo animal models of acute and chronic neurological disorders.

  18. Inhibition of radiation-induced glioblastoma invasion by genetic and pharmacological targeting of MDA-9/Syntenin.

    PubMed

    Kegelman, Timothy P; Wu, Bainan; Das, Swadesh K; Talukdar, Sarmistha; Beckta, Jason M; Hu, Bin; Emdad, Luni; Valerie, Kristoffer; Sarkar, Devanand; Furnari, Frank B; Cavenee, Webster K; Wei, Jun; Purves, Angela; De, Surya K; Pellecchia, Maurizio; Fisher, Paul B

    2017-01-10

    Glioblastoma multiforme (GBM) is an intractable tumor despite therapeutic advances, principally because of its invasive properties. Radiation is a staple in therapeutic regimens, although cells surviving radiation can become more aggressive and invasive. Subtraction hybridization identified melanoma differentiation-associated gene 9 [MDA-9/Syntenin; syndecan-binding protein (SDCBP)] as a differentially regulated gene associated with aggressive cancer phenotypes in melanoma. MDA-9/Syntenin, a highly conserved double-PDZ domain-containing scaffolding protein, is robustly expressed in human-derived GBM cell lines and patient samples, with expression increasing with tumor grade and correlating with shorter survival times and poorer response to radiotherapy. Knockdown of MDA-9/Syntenin sensitizes GBM cells to radiation, reducing postradiation invasion gains. Radiation induces Src and EGFRvIII signaling, which is abrogated through MDA-9/Syntenin down-regulation. A specific inhibitor of MDA-9/Syntenin activity, PDZ1i (113B7), identified through NMR-guided fragment-based drug design, inhibited MDA-9/Syntenin binding to EGFRvIII, which increased following radiation. Both genetic (shmda-9) and pharmacological (PDZ1i) targeting of MDA-9/Syntenin reduced invasion gains in GBM cells following radiation. Although not affecting normal astrocyte survival when combined with radiation, PDZ1i radiosensitized GBM cells. PDZ1i inhibited crucial GBM signaling involving FAK and mutant EGFR, EGFRvIII, and abrogated gains in secreted proteases, MMP-2 and MMP-9, following radiation. In an in vivo glioma model, PDZ1i resulted in smaller, less invasive tumors and enhanced survival. When combined with radiation, survival gains exceeded radiotherapy alone. MDA-9/Syntenin (SDCBP) provides a direct target for therapy of aggressive cancers such as GBM, and defined small-molecule inhibitors such as PDZ1i hold promise to advance targeted brain cancer therapy.

  19. Pharmacological HIF2α inhibition improves VHL disease-associated phenotypes in zebrafish model.

    PubMed

    Metelo, Ana Martins; Noonan, Haley R; Li, Xiang; Jin, Youngnam; Baker, Rania; Kamentsky, Lee; Zhang, Yiyun; van Rooijen, Ellen; Shin, Jordan; Carpenter, Anne E; Yeh, Jing-Ruey; Peterson, Randall T; Iliopoulos, Othon

    2015-05-01

    Patients with a germline mutation in von Hippel-Lindau (VHL) develop renal cell cancers and hypervascular tumors of the brain, adrenal glands, and pancreas as well as erythrocytosis. These phenotypes are driven by aberrant expression of HIF2α, which induces expression of genes involved in cell proliferation, angiogenesis, and red blood cell production. Currently, there are no effective treatments available for VHL disease. Here, using an animal model of VHL, we report a marked improvement of VHL-associated phenotypes following treatment with HIF2α inhibitors. Inactivation of vhl in zebrafish led to constitutive activation of HIF2α orthologs and modeled several aspects of the human disease, including erythrocytosis, pathologic angiogenesis in the brain and retina, and aberrant kidney and liver proliferation. Treatment of vhl(-/-) mutant embryos with HIF2α-specific inhibitors downregulated Hif target gene expression in a dose-dependent manner, improved abnormal hematopoiesis, and substantially suppressed erythrocytosis and angiogenic sprouting. Moreover, pharmacologic inhibition of HIF2α reversed the compromised cardiac contractility of vhl(-/-) embryos and partially rescued early lethality. This study demonstrates that small-molecule targeting of HIF2α improves VHL-related phenotypes in a vertebrate animal model and supports further exploration of this strategy for treating VHL disease.

  20. Pharmacological HIF2α inhibition improves VHL disease–associated phenotypes in zebrafish model

    PubMed Central

    Metelo, Ana Martins; Noonan, Haley R.; Li, Xiang; Jin, Youngnam; Baker, Rania; Kamentsky, Lee; Zhang, Yiyun; van Rooijen, Ellen; Shin, Jordan; Carpenter, Anne E.; Yeh, Jing-Ruey; Peterson, Randall T.; Iliopoulos, Othon

    2015-01-01

    Patients with a germline mutation in von Hippel-Lindau (VHL) develop renal cell cancers and hypervascular tumors of the brain, adrenal glands, and pancreas as well as erythrocytosis. These phenotypes are driven by aberrant expression of HIF2α, which induces expression of genes involved in cell proliferation, angiogenesis, and red blood cell production. Currently, there are no effective treatments available for VHL disease. Here, using an animal model of VHL, we report a marked improvement of VHL-associated phenotypes following treatment with HIF2α inhibitors. Inactivation of vhl in zebrafish led to constitutive activation of HIF2α orthologs and modeled several aspects of the human disease, including erythrocytosis, pathologic angiogenesis in the brain and retina, and aberrant kidney and liver proliferation. Treatment of vhl–/– mutant embryos with HIF2α-specific inhibitors downregulated Hif target gene expression in a dose-dependent manner, improved abnormal hematopoiesis, and substantially suppressed erythrocytosis and angiogenic sprouting. Moreover, pharmacologic inhibition of HIF2α reversed the compromised cardiac contractility of vhl–/– embryos and partially rescued early lethality. This study demonstrates that small-molecule targeting of HIF2α improves VHL-related phenotypes in a vertebrate animal model and supports further exploration of this strategy for treating VHL disease. PMID:25866969

  1. Aging and immortality: quasi-programmed senescence and its pharmacologic inhibition.

    PubMed

    Blagosklonny, Mikhail V

    2006-09-01

    While ruling out programmed aging, evolutionary theory predicts a quasi-program for aging, a continuation of the developmental program that is not turned off, is constantly on, becoming hyper-functional and damaging, causing diseases of aging. Could it be switched off pharmacologically? This would require identification of a molecular target involved in cell senescence, organism aging and diseases of aging. Notably, cell senescence is associated with activation of the TOR (target of rapamycin) nutrient- and mitogen-sensing pathway, which promotes cell growth, even though cell cycle is blocked. Is TOR involved in organism aging? In fact, in yeast (where the cell is the organism), caloric restriction, rapamycin and mutations that inhibit TOR all slow down aging. In animals from worms to mammals caloric restrictions, life-extending agents, and numerous mutations that increase longevity all converge on the TOR pathway. And, in humans, cell hypertrophy, hyper-function and hyperplasia, typically associated with activation of TOR, contribute to diseases of aging. Theoretical and clinical considerations suggest that rapamycin may be effective against atherosclerosis, hypertension and hyper-coagulation (thus, preventing myocardial infarction and stroke), osteoporosis, cancer, autoimmune diseases and arthritis, obesity, diabetes, macula-degeneration, Alzheimer's and Parkinson's diseases. Finally, I discuss that extended life span will reveal new causes for aging (e.g., ROS, 'wear and tear', Hayflick limit, stem cell exhaustion) that play a limited role now, when quasi-programmed senescence kills us first.

  2. Pharmacological inhibition of soluble epoxide hydrolase ameliorates diet-induced metabolic syndrome in rats.

    PubMed

    Iyer, Abishek; Kauter, Kathleen; Alam, Md Ashraful; Hwang, Sung Hee; Morisseau, Christophe; Hammock, Bruce D; Brown, Lindsay

    2012-01-01

    The signs of metabolic syndrome following chronic excessive macronutrient intake include body weight gain, excess visceral adipose deposition, hyperglycaemia, glucose and insulin intolerances, hypertension, dyslipidaemia, endothelial damage, cardiovascular hypertrophy, inflammation, ventricular contractile dysfunction, fibrosis, and fatty liver disease. Recent studies show increased activity of soluble epoxide hydrolase (sEH) during obesity and metabolic dysfunction. We have tested whether sEH inhibition has therapeutic potential in a rat model of diet-induced metabolic syndrome. In these high-carbohydrate, high-fat-fed rats, chronic oral treatment with trans-4-[4-(3-adamantan-1-ylureido)-cyclohexyloxy]-benzoic acid (t-AUCB), a potent sEH inhibitor, alleviated the signs of metabolic syndrome in vivo including glucose, insulin, and lipid abnormalities, changes in pancreatic structure, increased systolic blood pressure, cardiovascular structural and functional abnormalities, and structural and functional changes in the liver. The present study describes the pharmacological responses to this selective sEH inhibitor in rats with the signs of diet-induced metabolic syndrome.

  3. Probing the modulation of acute ethanol intoxication by pharmacological manipulation of the NMDAR glycine coagonist site

    PubMed Central

    Debrouse, Lauren; Hurd, Benita; Kiselycznyk, Carly; Plitt, Aaron; Todaro, Alyssa; Mishina, Masayoshi; Grant, Seth; Camp, Marguerite; Gunduz-Cinar, Ozge; Holmes, Andrew

    2012-01-01

    BACKGROUND Stimulating the glycineB binding site on the N-methyl-D-aspartate receptor (NMDAR) has been proposed as a novel mechanism for modulating behavioral effects of ethanol (EtOH) that are mediated via the NMDAR, including acute intoxication. Here, we pharmacologically interrogated this hypothesis in mice. METHODS Effects of systemic injection of the glycineB agonist, D-serine, the GlyT-1 glycine transporter inhibitor, ALX-5407, and the glycineB antagonist, L-701,324, were tested for effects on EtOH-induced ataxia, hypothermia, loss of righting reflex duration (LORR) in C57BL/6J (B6) and 129S1/SvImJ (S1) inbred mice. Effects of the glycineB partial agonist, D-cycloserine, the GlyT-1 inhibitor, NFPS, and the glycineB antagonist, DCKA, on EtOH-induced LORR duration were also tested. Interaction effects on EtOH-induced LORR duration were examined via combined treatment with D-serine and ALX-5407, D-serine and MK-801, D-serine and L-701,324, as well as L-701,324 and ALX-5407, in B6 mice, as D-serine in GluN2A and PSD-95 KO mice. The effect of dietary depletion of Magnesium (Mg), an element which interacts the glycineB site, was also tested. RESULTS Neither D-serine, D-cycloserine, ALX-5407, nor NFPS significantly affected EtOH intoxication on any of the measures or strains studied. L-701,324, but not DCKA, dose-dependently potentiated the ataxia-inducing effects of EtOH and increased EtOH-induced (but not pentobarbital-induced) LORR duration. D-serine did not have interactive effects on EtOH-induced LORR duration when combined with ALX-5407. The EtOH-potentiating effects of L-701,324, but not MK-801, on LORR duration were prevented by D-serine, but not ALX-5407. Mg depletion potentiated LORR duration in B6 mice and was lethal in a large proportion of S1 mice. CONCLUSIONS GlycineB site activation failed to produce the hypothesized reduction in EtOH intoxication across a range of measures and genetic strains, but blockade of the glycineB site potentiated Et

  4. An animal model of chronic inflammatory pain: pharmacological and temporal differentiation from acute models.

    PubMed

    Wilson, Alex W; Medhurst, Stephen J; Dixon, Claire I; Bontoft, Nick C; Winyard, Lisa A; Brackenborough, Kim T; De Alba, Jorge; Clarke, Christopher J; Gunthorpe, Martin J; Hicks, Gareth A; Bountra, Chas; McQueen, Daniel S; Chessell, Iain P

    2006-08-01

    Clinically, inflammatory pain is far more persistent than that typically modelled pre-clinically, with the majority of animal models focussing on short-term effects of the inflammatory pain response. The large attrition rate of compounds in the clinic which show pre-clinical efficacy suggests the need for novel models of, or approaches to, chronic inflammatory pain if novel mechanisms are to make it to the market. A model in which a more chronic inflammatory hypersensitivity phenotype is profiled may allow for a more clinically predictive tool. The aims of these studies were to characterise and validate a chronic model of inflammatory pain. We have shown that injection of a large volume of adjuvant to the intra-articular space of the rat knee results in a prolonged inflammatory pain response, compared to the response in an acute adjuvant model. Additionally, this model also results in a hypersensitive state in the presence and absence of inflammation. A range of clinically effective analgesics demonstrate activity in this chronic model, including morphine (3mg/kg, t.i.d.), dexamethasone (1mg/kg, b.i.d.), ibuprofen (30mg/kg, t.i.d.), etoricoxib (5mg/kg, b.i.d.) and rofecoxib (0.3-10mg/kg, b.i.d.). A further aim was to exemplify the utility of this chronic model over the more acute intra-plantar adjuvant model using two novel therapeutic approaches; NR2B selective NMDA receptor antagonism and iNOS inhibition. Our data shows that different effects were observed with these therapies when comparing the acute model with the model of chronic inflammatory joint pain. These data suggest that the chronic model may be more relevant to identifying mechanisms for the treatment of chronic inflammatory pain states in the clinic.

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

    PubMed Central

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

    2016-01-01

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

  6. Acute aerobic exercise modulates primary motor cortex inhibition.

    PubMed

    Mooney, Ronan A; Coxon, James P; Cirillo, John; Glenny, Helen; Gant, Nicholas; Byblow, Winston D

    2016-12-01

    Aerobic exercise can enhance neuroplasticity although presently the neural mechanisms underpinning these benefits remain unclear. One possible mechanism is through effects on primary motor cortex (M1) function via down-regulation of the inhibitory neurotransmitter gamma-aminobutyric acid (GABA). The aim of the present study was to examine how corticomotor excitability (CME) and M1 intracortical inhibition are modulated in response to a single bout of moderate intensity aerobic exercise. Ten healthy right-handed adults were participants. Single- and paired-pulse transcranial magnetic stimulation was applied over left M1 to obtain motor-evoked potentials in the right flexor pollicis brevis. We examined CME, cortical silent period (SP) duration, short- and long-interval intracortical inhibition (SICI, LICI), and late cortical disinhibition (LCD), before and after acute aerobic exercise (exercise session) or an equivalent duration without exercise (control session). Aerobic exercise was performed on a cycle ergometer for 30 min at a workload equivalent to 60 % of maximal cardiorespiratory fitness (VO2 peak; heart rate reserve = 75 ± 3 %, perceived exertion = 13.5 ± 0.7). LICI was reduced at 10 (52 ± 17 %, P = 0.03) and 20 min (27 ± 8 %, P = 0.03) post-exercise compared to baseline (13 ± 4 %). No significant changes in CME, SP duration, SICI or LCD were observed. The present study shows that GABAB-mediated intracortical inhibition may be down-regulated after acute aerobic exercise. The potential effects this may have on M1 plasticity remain to be determined.

  7. Pharmacological inhibition of CXCR2 chemokine receptors modulates paraquat-induced intoxication in rats.

    PubMed

    Costa, Kesiane M; Maciel, Izaque S; Kist, Luiza W; Campos, Maria M; Bogo, Maurício R

    2014-01-01

    Paraquat (PQ) is an agrochemical agent commonly used worldwide, which is allied to potential risks of intoxication. This herbicide induces the formation of reactive oxygen species (ROS) that ends up compromising various organs, particularly the lungs and the brain. This study evaluated the deleterious effects of paraquat on the central nervous system (CNS) and peripherally, with special attempts to assess the putative protective effects of the selective CXCR2 receptor antagonist SB225002 on these parameters. PQ-toxicity was induced in male Wistar rats, in a total dose of 50 mg/kg, and control animals received saline solution at the same schedule of administration. Separate groups of animals were treated with the selective CXCR2 antagonist SB225002 (1 or 3 mg/kg), administered 30 min before each paraquat injection. The major changes found in paraquat-treated animals were: decreased body weight and hypothermia, nociception behavior, impairment of locomotor and gait capabilities, enhanced TNF-α and IL-1β expression in the striatum, and cell migration to the lungs and blood. Some of these parameters were reversed when the antagonist SB225002 was administered, including recovery of physiological parameters, decreased nociception, improvement of gait abnormalities, modulation of striatal TNF-α and IL-1β expression, and decrease of neutrophil migration to the lungs and blood. Taken together, our results demonstrate that damage to the central and peripheral systems elicited by paraquat can be prevented by the pharmacological inhibition of CXCR2 chemokine receptors. The experimental evidence presented herein extends the comprehension on the toxicodynamic aspects of paraquat, and opens new avenues to treat intoxication induced by this herbicide.

  8. (S)-lacosamide inhibition of CRMP2 phosphorylation reduces postoperative and neuropathic pain behaviors through distinct classes of sensory neurons identified by constellation pharmacology.

    PubMed

    Moutal, Aubin; Chew, Lindsey A; Yang, Xiaofang; Wang, Yue; Yeon, Seul Ki; Telemi, Edwin; Meroueh, Seeneen; Park, Ki Duk; Shrinivasan, Raghuraman; Gilbraith, Kerry B; Qu, Chaoling; Xie, Jennifer Y; Patwardhan, Amol; Vanderah, Todd W; Khanna, May; Porreca, Frank; Khanna, Rajesh

    2016-07-01

    Chronic pain affects the life of millions of people. Current treatments have deleterious side effects. We have advanced a strategy for targeting protein interactions which regulate the N-type voltage-gated calcium (CaV2.2) channel as an alternative to direct channel block. Peptides uncoupling CaV2.2 interactions with the axonal collapsin response mediator protein 2 (CRMP2) were antinociceptive without effects on memory, depression, and reward/addiction. A search for small molecules that could recapitulate uncoupling of the CaV2.2-CRMP2 interaction identified (S)-lacosamide [(S)-LCM], the inactive enantiomer of the Food and Drug Administration-approved antiepileptic drug (R)-lacosamide [(R)-LCM, Vimpat]. We show that (S)-LCM, but not (R)-LCM, inhibits CRMP2 phosphorylation by cyclin dependent kinase 5, a step necessary for driving CaV2.2 activity, in sensory neurons. (S)-lacosamide inhibited depolarization-induced Ca influx with a low micromolar IC50. Voltage-clamp electrophysiology experiments demonstrated a commensurate reduction in Ca currents in sensory neurons after an acute application of (S)-LCM. Using constellation pharmacology, a recently described high content phenotypic screening platform for functional fingerprinting of neurons that uses subtype-selective pharmacological agents to elucidate cell-specific combinations (constellations) of key signaling proteins that define specific cell types, we investigated if (S)-LCM preferentially acts on certain types of neurons. (S)-lacosamide decreased the dorsal root ganglion neurons responding to mustard oil, and increased the number of cells responding to menthol. Finally, (S)-LCM reversed thermal hypersensitivity and mechanical allodynia in a model of postoperative pain, and 2 models of neuropathic pain. Thus, using (S)-LCM to inhibit CRMP2 phosphorylation is a novel and efficient strategy to treat pain, which works by targeting specific sensory neuron populations.

  9. Acute uptake inhibition increases extracellular serotonin in the rat forebrain.

    PubMed

    Rutter, J J; Auerbach, S B

    1993-06-01

    The effect of acute uptake inhibition on serotonin (5-HT) in the rat central nervous system was monitored by using in vivo dialysis. Peripheral administration of the selective 5-HT uptake blocker, fluoxetine, caused a dose-dependent increase in extracellular 5-HT in both the diencephalon and the striatum. Administration of fluoxetine or sertraline, another selective 5-HT uptake inhibitor, caused a prolonged (24 hr) increase in 5-HT and decrease in 5-hydroxyindoleacetic acid. In addition, fluoxetine and sertraline attenuated the 5-HT releasing effect of fenfluramine administered 24 hr later. Local infusion of fluoxetine into the diencephalon caused an increase in 5-HT that was twice as large as the effect of peripheral injection. Peripheral fluoxetine, by enhancing extracellular 5-HT in the raphe, probably resulted in activation of somatodendritic autoreceptors and inhibition of 5-HT neuronal discharge. Thus, the increase in 5-HT in the diencephalon after peripheral fluoxetine presumably reflected a balance between decreased release and inhibition of reuptake. In support of this, after first infusing fluoxetine into the diencephalon to maximally block reuptake, peripheral injection of the uptake inhibitor caused a decrease in 5-HT.

  10. Acute and subchronic toxicity as well as evaluation of safety pharmacology of eucalyptus oil-water emulsions

    PubMed Central

    Hu, Zhiqiang; Feng, Ruizhang; Xiang, Fa; Song, Xu; Yin, Zhongqiong; Zhang, Chao; Zhao, Xinghong; Jia, Renyong; Chen, Zhenzhen; Li, Li; Yin, Lizi; Liang, Xiaoxia; He, Changliang; Shu, Gang; Lv, Cheng; Zhao, Ling; Ye, Gang; Shi, Fei

    2014-01-01

    Essential oil has performed a variety of indirect services used as insect/pest repellent. The present study investigated the acute and subchronic toxicity of eucalyptus oil emulsion in water (EOE). In addition, we conduct safety pharmacology evaluation of EOE to supplement the toxicity tests and provide a basis for a comprehensive understanding of the toxicity of EOE. Acute administration of EOE was done as single dose from 2772 mg to 5742 mg of EOE per kg/bodyweight (b.wt.) and subchronic toxicity study for thirty days was done by daily oral administration of EOE at doses of 396, 792 and 1188 mg/kg b.wt. In SPF SD rats. The acute toxicity study showed the LD50 of EOE was 3811.5 mg/kg. The subchronic toxicity study suggested the high-dose and middle-dose EOE slowed down the growth of male rats. The clinical pathology showed the high-dose and middle-dose EOE could cause damage to liver and kidney. The safety pharmacology indicated that EOE had no side effects on rats. These results suggest that EOE is a safe veterinary medicine for external use. PMID:25663980

  11. GATA2 Inhibition Sensitizes Acute Myeloid Leukemia Cells to Chemotherapy

    PubMed Central

    Cao, Yanan; Xuan, Binbin; Fan, Yingchao; Sheng, Huiming; Zhuang, Wenfang

    2017-01-01

    Drug resistance constitutes one of the main obstacles for clinical recovery of acute myeloid leukemia (AML) patients. Therefore, the treatment of AML requires new strategies, such as adding a third drug. To address whether GATA2 could act as a regulator of chemotherapy resistance in human leukemia cells, we observed KG1a cells and clinical patients’ AML cells with a classic drug (Cerubidine) and Gefitinib. After utilizing chemotherapy, the expression of GATA2 and its target genes (EVI, SCL and WT1) in surviving AML cells and KG1a cells were significantly enhanced to double and quadrupled compared to its original level respectively. Furthermore, with continuous chemotherapeutics, AML cells with GATA2 knockdown or treated with GATA2 inhibitor (K1747) almost eliminated with dramatically reduced expression of WT1, SCL, EVI, and significantly increased apoptotic population. Therefore, we propose that reducing GATA2 expression or inhibition of its transcription activity can relieve the drug resistance of acute myeloid leukemia cells and it would be helpful for eliminating the leukemia cells in patients. PMID:28114350

  12. Neuroprotection mediated by inhibition of calpain during acute viral encephalitis

    PubMed Central

    Howe, Charles L.; LaFrance-Corey, Reghann G.; Mirchia, Kanish; Sauer, Brian M.; McGovern, Renee M.; Reid, Joel M.; Buenz, Eric J.

    2016-01-01

    Neurologic complications associated with viral encephalitis, including seizures and cognitive impairment, are a global health issue, especially in children. We previously showed that hippocampal injury during acute picornavirus infection in mice is associated with calpain activation and is the result of neuronal death triggered by brain-infiltrating inflammatory monocytes. We therefore hypothesized that treatment with a calpain inhibitor would protect neurons from immune-mediated bystander injury. C57BL/6J mice infected with the Daniel’s strain of Theiler’s murine encephalomyelitis virus were treated with the FDA-approved drug ritonavir using a dosing regimen that resulted in plasma concentrations within the therapeutic range for calpain inhibition. Ritonavir treatment significantly reduced calpain activity in the hippocampus, protected hippocampal neurons from death, preserved cognitive performance, and suppressed seizure escalation, even when therapy was initiated 36 hours after disease onset. Calpain inhibition by ritonavir may be a powerful tool for preserving neurons and cognitive function and preventing neural circuit dysregulation in humans with neuroinflammatory disorders. PMID:27345730

  13. Small molecule activation of NOTCH signaling inhibits acute myeloid leukemia

    PubMed Central

    Ye, Qi; Jiang, Jue; Zhan, Guanqun; Yan, Wanyao; Huang, Liang; Hu, Yufeng; Su, Hexiu; Tong, Qingyi; Yue, Ming; Li, Hua; Yao, Guangmin; Zhang, Yonghui; Liu, Hudan

    2016-01-01

    Aberrant activation of the NOTCH signaling pathway is crucial for the onset and progression of T cell leukemia. Yet recent studies also suggest a tumor suppressive role of NOTCH signaling in acute myeloid leukemia (AML) and reactivation of this pathway offers an attractive opportunity for anti-AML therapies. N-methylhemeanthidine chloride (NMHC) is a novel Amaryllidaceae alkaloid that we previously isolated from Zephyranthes candida, exhibiting inhibitory activities in a variety of cancer cells, particularly those from AML. Here, we report NMHC not only selectively inhibits AML cell proliferation in vitro but also hampers tumor development in a human AML xenograft model. Genome-wide gene expression profiling reveals that NMHC activates the NOTCH signaling. Combination of NMHC and recombinant human NOTCH ligand DLL4 achieves a remarkable synergistic effect on NOTCH activation. Moreover, pre-inhibition of NOTCH by overexpression of dominant negative MAML alleviates NMHC-mediated cytotoxicity in AML. Further mechanistic analysis using structure-based molecular modeling as well as biochemical assays demonstrates that NMHC docks in the hydrophobic cavity within the NOTCH1 negative regulatory region (NRR), thus promoting NOTCH1 proteolytic cleavage. Our findings thus establish NMHC as a potential NOTCH agonist that holds great promises for future development as a novel agent beneficial to patients with AML. PMID:27211848

  14. Pharmacology of antiplatelet agents.

    PubMed

    Kalra, Kiran; Franzese, Christopher J; Gesheff, Martin G; Lev, Eli I; Pandya, Shachi; Bliden, Kevin P; Tantry, Udaya S; Gurbel, Paul A

    2013-12-01

    Pharmacotherapies with agents that inhibit platelet function have proven to be effective in the treatment of acute coronary syndromes, and in the prevention of complications during and after percutaneous coronary intervention. Because of multiple synergetic pathways of platelet activation and their close interplay with coagulation, current treatment strategies are based not only on platelet inhibition, but also on the attenuation of procoagulant activity, inhibition of thrombin generation, and enhancement of clot dissolution. Current strategies can be broadly categorized as anticoagulants, antiplatelet agents, and fibrinolytics. This review focuses on the pharmacology of current antiplatelet therapy primarily targeting the inhibition of the enzyme cyclooxygenase 1, the P2Y12 receptor, the glycoprotein IIb/IIIa receptor, and protease-activated receptor 1.

  15. CDK4/6 inhibition induces epithelial cell cycle arrest and ameliorates acute kidney injury

    PubMed Central

    DiRocco, Derek P.; Bisi, John; Roberts, Patrick; Strum, Jay; Wong, Kwok-Kin; Sharpless, Norman

    2013-01-01

    Acute kidney injury (AKI) is common and urgently requires new preventative therapies. Expression of a cyclin-dependent kinase (CDK) inhibitor transgene protects against AKI, suggesting that manipulating the tubular epithelial cell cycle may be a viable therapeutic strategy. Broad spectrum small molecule CDK inhibitors are protective in some kidney injury models, but these have toxicities and epithelial proliferation is eventually required for renal repair. Here, we tested a well-tolerated, novel and specific small molecule inhibitor of CDK4 and CDK6, PD 0332991, to investigate the effects of transient cell cycle inhibition on epithelial survival in vitro and kidney injury in vivo. We report that CDK4/6 inhibition induced G0/G1 cycle arrest in cultured human renal proximal tubule cells (hRPTC) at baseline and after injury. Induction of transient G0/G1 cycle arrest through CDK4/6 inhibition protected hRPTC from DNA damage and caspase 3/7 activation following exposure to the nephrotoxins cisplatin, etoposide, and antimycin A. In vivo, mice treated with PD 0332991 before ischemia-reperfusion injury (IRI) exhibited dramatically reduced epithelial progression through S phase 24 h after IRI. Despite reduced epithelial proliferation, PD 0332991 ameliorated kidney injury as reflected by improved serum creatinine and blood urea nitrogen levels 24 h after injury. Inflammatory markers and macrophage infiltration were significantly decreased in injured kidneys 3 days following IRI. These results indicate that induction of proximal tubule cell cycle arrest with specific CDK4/6 inhibitors, or “pharmacological quiescence,” represents a novel strategy to prevent AKI. PMID:24338822

  16. Acute inhibition of myostatin-family proteins preserves skeletal muscle in mouse models of cancer cachexia

    SciTech Connect

    Benny Klimek, Margaret E.; Aydogdu, Tufan; Link, Majik J.; Pons, Marianne; Koniaris, Leonidas G.; Zimmers, Teresa A.

    2010-01-15

    Cachexia, progressive loss of fat and muscle mass despite adequate nutrition, is a devastating complication of cancer associated with poor quality of life and increased mortality. Myostatin is a potent tonic muscle growth inhibitor. We tested how myostatin inhibition might influence cancer cachexia using genetic and pharmacological approaches. First, hypermuscular myostatin null mice were injected with Lewis lung carcinoma or B16F10 melanoma cells. Myostatin null mice were more sensitive to tumor-induced cachexia, losing more absolute mass and proportionately more muscle mass than wild-type mice. Because myostatin null mice lack expression from development, however, we also sought to manipulate myostatin acutely. The histone deacetylase inhibitor Trichostatin A has been shown to increase muscle mass in normal and dystrophic mice by inducing the myostatin inhibitor, follistatin. Although Trichostatin A administration induced muscle growth in normal mice, it failed to preserve muscle in colon-26 cancer cachexia. Finally we sought to inhibit myostatin and related ligands by administration of the Activin receptor extracellular domain/Fc fusion protein, ACVR2B-Fc. Systemic administration of ACVR2B-Fc potently inhibited muscle wasting and protected adipose stores in both colon-26 and Lewis lung carcinoma cachexia, without affecting tumor growth. Enhanced cachexia in myostatin knockouts indicates that host-derived myostatin is not the sole mediator of muscle wasting in cancer. More importantly, skeletal muscle preservation with ACVR2B-Fc establishes that targeting myostatin-family ligands using ACVR2B-Fc or related molecules is an important and potent therapeutic avenue in cancer cachexia.

  17. Sex differences in Δ(9)-tetrahydrocannabinol metabolism and in vivo pharmacology following acute and repeated dosing in adolescent rats.

    PubMed

    Wiley, Jenny L; Burston, James J

    2014-07-25

    Mechanisms that may underlie age and sex differences in the pharmacological effects of cannabinoids are relatively unexplored. The purpose of the present study was to determine whether sex differences in metabolism of Δ(9)-tetrahydrocannabinol (THC), similar to those observed previously in adult rats, also occurred in adolescent rats and might contribute to age and sex differences in its in vivo pharmacology. Male and female adolescent rats were exposed to THC acutely or repeatedly for 10 days. Subsequently, some of the rats were sacrificed and blood and brain levels of THC and one of its metabolites, 11-hydroxy-Δ(9)-THC (11-OH-THC), were measured. Other rats were evaluated in a battery of in vivo tests that are sensitive to cannabinoids. Concentrations of 11-OH-THC in the brains of female adult and adolescent rats exceeded those observed in male conspecifics, particularly after repeated THC administration. In contrast, brain levels of THC did not differ between the sexes. In vivo, acute THC produced dose-related hypothermia, catalepsy and suppression of locomotion in adolescent rats of both sexes, with tolerance developing after repeated administration. With a minor exception, sex differences in THC's effects in the in vivo assays were not apparent. Together with previous findings, the present results suggest that sex differences in pharmacokinetics cannot fully explain the patterns of sex differences (and lack of sex differences) in cannabinoid effects across behaviors. Hormonal and/or pharmacodynamic factors are also likely to play a role.

  18. Genetic and Pharmacological Inhibition of PDK1 in Cancer Cells: Characterization of a Selective Allosteric Kinase Inhibitor

    SciTech Connect

    Nagashima, Kumiko; Shumway, Stuart D.; Sathyanarayanan, Sriram; Chen, Albert H.; Dolinski, Brian; Xu, Youyuan; Keilhack, Heike; Nguyen, Thi; Wiznerowicz, Maciej; Li, Lixia; Lutterbach, Bart A.; Chi, An; Paweletz, Cloud; Allison, Timothy; Yan, Youwei; Munshi, Sanjeev K.; Klippel, Anke; Kraus, Manfred; Bobkova, Ekaterina V.; Deshmukh, Sujal; Xu, Zangwei; Mueller, Uwe; Szewczak, Alexander A.; Pan, Bo-Sheng; Richon, Victoria; Pollock, Roy; Blume-Jensen, Peter; Northrup, Alan; Andersen, Jannik N.

    2013-11-20

    Phosphoinositide-dependent kinase 1 (PDK1) is a critical activator of multiple prosurvival and oncogenic protein kinases and has garnered considerable interest as an oncology drug target. Despite progress characterizing PDK1 as a therapeutic target, pharmacological support is lacking due to the prevalence of nonspecific inhibitors. Here, we benchmark literature and newly developed inhibitors and conduct parallel genetic and pharmacological queries into PDK1 function in cancer cells. Through kinase selectivity profiling and x-ray crystallographic studies, we identify an exquisitely selective PDK1 inhibitor (compound 7) that uniquely binds to the inactive kinase conformation (DFG-out). In contrast to compounds 1-5, which are classical ATP-competitive kinase inhibitors (DFG-in), compound 7 specifically inhibits cellular PDK1 T-loop phosphorylation (Ser-241), supporting its unique binding mode. Interfering with PDK1 activity has minimal antiproliferative effect on cells growing as plastic-attached monolayer cultures (i.e. standard tissue culture conditions) despite reduced phosphorylation of AKT, RSK, and S6RP. However, selective PDK1 inhibition impairs anchorage-independent growth, invasion, and cancer cell migration. Compound 7 inhibits colony formation in a subset of cancer cell lines (four of 10) and primary xenograft tumor lines (nine of 57). RNAi-mediated knockdown corroborates the PDK1 dependence in cell lines and identifies candidate biomarkers of drug response. In summary, our profiling studies define a uniquely selective and cell-potent PDK1 inhibitor, and the convergence of genetic and pharmacological phenotypes supports a role of PDK1 in tumorigenesis in the context of three-dimensional in vitro culture systems.

  19. Pharmacological blockade of small conductance Ca(2+)-activated K(+) channels by ICA reduces arrhythmic load in rats with acute myocardial infarction.

    PubMed

    Hundahl, Laura A; Sattler, Stefan M; Skibsbye, Lasse; Diness, Jonas G; Tfelt-Hansen, Jacob; Jespersen, Thomas

    2017-03-11

    Acute myocardial infarction (AMI) with development of ventricular fibrillation (VF) is a common cause of sudden cardiac death (SCD). At present, no pharmacological treatment has successfully been able to prevent VF in the acute stage of AMI. This study investigates the antiarrhythmic effect of inhibiting small conductance Ca(2+)-activated K(+) (SK) channels using the pore blocker N-(pyridin-2-yl)-4-(pyridin-2-yl)thiazol-2-amine (ICA) in AMI rats. Acute coronary ligation was performed in 26 anesthetized rats, and ECG, monophasic action potentials (MAPs), and ventricular effective refractory period (vERP) were recorded. Rats were randomized into four groups: (i) 3 mg/kg i.v. ICA with AMI (AMI-ICA-group, n = 9), (ii) vehicle with AMI (AMI-vehicle-group, n = 9), (iii) vehicle with sham operation (sham-vehicle-group, n = 8), and (iv) 3 mg/kg i.v. ICA with sham operation (sham-ICA-group, n = 6). At the end of experiments, hearts were stained for the non-perfused area at risk (AAR). AMI resulted in the development of ventricular tachycardia (VT) in all AMI-vehicle and AMI-ICA rats; however, ICA significantly decreased VT duration. VF occurred in 44% of AMI-vehicle rats but not in AMI-ICA rats. Monophasic action potential duration at 80% repolarization (MAPD80) in the ischemic area decreased rapidly in both AMI-vehicle and AMI-ICA rats. However, 5 min after occlusion, MAPD80 returned to baseline in AMI-ICA rats but not in AMI-vehicle rats. The vERP was prolonged in the AMI-ICA group compared to AMI-vehicle after ligation. AAR was similar between the AMI-vehicle group and the AMI-ICA group. In rats with AMI, ICA reduces the burden of arrhythmia.

  20. Pharmacological inhibition of adipose triglyceride lipase corrects high-fat diet-induced insulin resistance and hepatosteatosis in mice

    PubMed Central

    Schweiger, Martina; Romauch, Matthias; Schreiber, Renate; Grabner, Gernot F.; Hütter, Sabrina; Kotzbeck, Petra; Benedikt, Pia; Eichmann, Thomas O.; Yamada, Sohsuke; Knittelfelder, Oskar; Diwoky, Clemens; Doler, Carina; Mayer, Nicole; De Cecco, Werner; Breinbauer, Rolf; Zimmermann, Robert; Zechner, Rudolf

    2017-01-01

    Elevated circulating fatty acids (FAs) contribute to the development of obesity-associated metabolic complications such as insulin resistance (IR) and non-alcoholic fatty liver disease (NAFLD). Hence, reducing adipose tissue lipolysis to diminish the mobilization of FAs and lower their respective plasma concentrations represents a potential treatment strategy to counteract obesity-associated disorders. Here we show that specific inhibition of adipose triglyceride lipase (Atgl) with the chemical inhibitor, Atglistatin, effectively reduces adipose tissue lipolysis, weight gain, IR and NAFLD in mice fed a high-fat diet. Importantly, even long-term treatment does not lead to lipid accumulation in ectopic tissues such as the skeletal muscle or heart. Thus, the severe cardiac steatosis and cardiomyopathy that is observed in genetic models of Atgl deficiency does not occur in Atglistatin-treated mice. Our data validate the pharmacological inhibition of Atgl as a potentially powerful therapeutic strategy to treat obesity and associated metabolic disorders. PMID:28327588

  1. Mechanism of mitochondrial permeability transition pore induction and damage in the pancreas: inhibition prevents acute pancreatitis by protecting production of ATP

    PubMed Central

    Mukherjee, Rajarshi; Mareninova, Olga A; Odinokova, Irina V; Huang, Wei; Murphy, John; Chvanov, Michael; Javed, Muhammad A; Wen, Li; Booth, David M; Cane, Matthew C; Awais, Muhammad; Gavillet, Bruno; Pruss, Rebecca M; Schaller, Sophie; Molkentin, Jeffery D; Tepikin, Alexei V; Petersen, Ole H; Pandol, Stephen J; Gukovsky, Ilya; Criddle, David N; Gukovskaya, Anna S

    2016-01-01

    Objective Acute pancreatitis is caused by toxins that induce acinar cell calcium overload, zymogen activation, cytokine release and cell death, yet is without specific drug therapy. Mitochondrial dysfunction has been implicated but the mechanism not established. Design We investigated the mechanism of induction and consequences of the mitochondrial permeability transition pore (MPTP) in the pancreas using cell biological methods including confocal microscopy, patch clamp technology and multiple clinically representative disease models. Effects of genetic and pharmacological inhibition of the MPTP were examined in isolated murine and human pancreatic acinar cells, and in hyperstimulation, bile acid, alcoholic and choline-deficient, ethionine-supplemented acute pancreatitis. Results MPTP opening was mediated by toxin-induced inositol trisphosphate and ryanodine receptor calcium channel release, and resulted in diminished ATP production, leading to impaired calcium clearance, defective autophagy, zymogen activation, cytokine production, phosphoglycerate mutase 5 activation and necrosis, which was prevented by intracellular ATP supplementation. When MPTP opening was inhibited genetically or pharmacologically, all biochemical, immunological and histopathological responses of acute pancreatitis in all four models were reduced or abolished. Conclusions This work demonstrates the mechanism and consequences of MPTP opening to be fundamental to multiple forms of acute pancreatitis and validates the MPTP as a drug target for this disease. PMID:26071131

  2. [Study of possible involvement of MEK mitogen-activated protein kinase and TGF-β receptor in planarian regeneration processes using pharmacological inhibition analysis].

    PubMed

    Ermakov, A M; Ermakova, O N; Ermolaeva, S A

    2014-01-01

    Possible involvement of MEK mitogen-activated protein kinase and TGF-β receptor in the processes of regeneration and morphogenesis in freshwater planarian flatworms Schmidtea mediterranea was studied using a pharmacological inhibitor analysis. It was found that pharmacological inhibitors of these kinases significantly inhibit the regeneration of the head end of the animals and that this effect is realized due to inhibition of proliferative activity of neoblasts, planarian stem cells. It is shown that that the inhibition of the studied protein kinases in regenerating planarians markedly disturbs stem cell differentiation and morphogenesis.

  3. Hsp90 inhibition ameliorates CD4+ T cell‐mediated acute Graft versus Host disease in mice

    PubMed Central

    Kerkau, Thomas; Werner, Sandra; Wolf, Nelli; Winter, Nadine; Hünig, Thomas; Einsele, Hermann; Topp, Max S.; Beyersdorf, Niklas

    2016-01-01

    Abstract Introduction For many patients with leukemia only allogeneic bone marrow transplantion provides a chance of cure. Co‐transplanted mature donor T cells mediate the desired Graft versus Tumor (GvT) effect required to destroy residual leukemic cells. The donor T cells very often, however, also attack healthy tissue of the patient inducing acute Graft versus Host Disease (aGvHD)—a potentially life‐threatening complication. Methods Therefore, we used the well established C57BL/6 into BALB/c mouse aGvHD model to evaluate whether pharmacological inhibition of heat shock protein 90 (Hsp90) would protect the mice from aGvHD. Results Treatment of the BALB/c recipient mice from day 0 to +2 after allogeneic CD4+ T cell transplantation with the Hsp90 inhibitor 17‐(dimethylaminoethylamino)‐17‐demethoxygeldanamycin (DMAG) partially protected the mice from aGvHD. DMAG treatment was, however, insufficient to prolong overall survival of leukemia‐bearing mice after transplantation of allogeneic CD4+ and CD8+ T cells. Ex vivo analyses and in vitro experiments revealed that DMAG primarily inhibits conventional CD4+ T cells with a relative resistance of CD4+ regulatory and CD8+ T cells toward Hsp90 inhibition. Conclusions Our data, thus, suggest that Hsp90 inhibition might constitute a novel approach to reduce aGvHD in patients without abrogating the desired GvT effect. PMID:27980780

  4. Synthesis and Pharmacological Evaluation of 4-Iminothiazolidinones for Inhibition of PI3 Kinase

    PubMed Central

    Pinson, Jo-Anne; Schmidt-Kittler, Oleg; Frazzetto, Mark; Zheng, Zhaohua; Jennings, Ian G.; Kinzler, Kenneth W.; Vogelstein, Bert; Chalmers, David K.; Thompson, Philip E.

    2012-01-01

    The thiazolidinedione, compound 1, has previously shown pan-inhibition of the phosphoinositide 3-kinase (PI3K) class I isoforms. We hypothesized the derivatization of the thiazolidinedione core of compound 1 could introduce isoform selectivity. We report the synthesis, characterization, and inhibitory activity of a novel series of 4-iminothiazolidin-2-ones for inhibition of the class I PI3K isoforms. Their synthesis was successfully achieved by multiple pathways described in this paper. Initial in vitro data of 28 analogues demonstrated poor inhibition of all class I PI3K isoforms. However, we identified an alternate target, the phosphodiesterases, and present preliminary screening results showing improved inhibitory activity. PMID:23997244

  5. Pharmacological modulation of transmitter release by inhibition of pressure-dependent potassium currents in vestibular hair cells.

    PubMed

    Haasler, Thorsten; Homann, Georg; Duong Dinh, Thien An; Jüngling, Eberhard; Westhofen, Martin; Lückhoff, Andreas

    2009-12-01

    Vestibular vertigo may be induced by increases in the endolymphatic pressure that activate pressure-dependent K(+) currents (I(K,p)) in vestibular hair cells. I(K,p) have been demonstrated to modulate transmitter release and are inhibited by low concentrations of cinnarizine. Beneficial effects against vestibular vertigo of cinnarizine have been attributed to its inhibition of calcium currents. Our aim was to determine the extent by which the inhibition of I(K,p) by cinnarizine may alter the voltage response to stimulating currents and to analyze whether such alterations may be sufficient to modulate the activation of Ca(2+) currents and transmitter release. Vestibular type II hair cells from guinea pigs were studied using the whole-cell patch-clamp technique. In current clamp, voltage responses to trains of stimulating currents were recorded. In voltage clamp, transmitter release was assessed from changes in the cell capacitance, as calculated from the phase shift during application of sine waves. Cinnarizine (0.05-3 microM) concentration dependently reversed the depressing effects of increases in the hydrostatic pressure (from 0.2 to 0.5 cm H(2)O) on the voltage responses to stimulating currents. Voltage protocols that simulated these responses were applied in voltage clamp and revealed a significantly enhanced transmitter release in conditions mimicking an inhibition of I(K,p). Cinnarizine (< or =0.5 microM) did not inhibit calcium currents. We conclude that cinnarizine, in pharmacologically relevant concentrations, enhances transmitter release in the presence of elevated hydrostatic pressure by an indirect mechanism, involving inhibition of I(K,p), enhancing depolarization, and increasing the voltage-dependent activation of Ca(2+) currents, without directly affecting Ca(2+) current.

  6. Acute and subchronic toxicity as well as evaluation of safety pharmacology of traditional Chinese medicine “Huhezi”

    PubMed Central

    Chen, Yaqin; Chen, Shufan; Song, Chenhui; Yin, Zhongqiong; Chen, Zhenzhen; Jia, Renyong; Liang, Xiaoxia; Li, Lixia; Zou, Yuanfeng; He, Changliang; Ye, Gang; Lv, Cheng

    2015-01-01

    The study was conducted to evaluate the toxicity and safety pharmacology of the traditional Chinese medicine, “Huhezi” granules. The results of acute toxicity test showed that the granules’ LD50 was more than 5000 mg/kg, which indicated that the “Huhezi” belonged to actually non-toxic drug. Subchronic toxicity study showed that non-toxic reaction were detected in high (1000 mg/kg), medium (500 mg/kg) and low dose (250 mg/kg) of “Huhezi” groups by measuring rat body weight, organ coefficient, blood physiological indexes and blood biochemical indexes. Pathological examination showed that no tissue lesions were observed in test organs except liver (mild granular degenerationand reversible vesicular degeneration), spleen (Langerhans cells infiltrating) and kidney (homogeneous red staining of renal tubule). Safety pharmacology study found that “Huhezi” had no effects on the central nervous system, respiratory system and cardiovascular system. These results suggested that the dose of “Huhezi” at or below 1000 mg/kg through oral administration is considered safe. PMID:26550447

  7. Spautin-1 Ameliorates Acute Pancreatitis via Inhibiting Impaired Autophagy and Alleviating Calcium Overload

    PubMed Central

    Xiao, Juan; Feng, Xueping; Huang, Xiao-Ying; Huang, Zhongshi; Huang, Yanqiang; Li, Chaogan; Li, Genliang; Nong, Song; Wu, Ruoshi; Huang, Yongzhi; Long, Xi-Dai

    2016-01-01

    Acute pancreatitis is characterized by zymogen preactivation. Severe inflammation caused by zymogen activation can eventually lead to multiple organ dysfunctions which contribute to the high mortality rate of severe acute pancreatitis. However, there is no specific treatment available for acute pancreatitis therapy. Here, we show that spautin-1, which effectively inhibits autophagy flux, ameliorated the pathogenesis of acute pancreatitis induced by cerulein or L-arginine. CaMKII phosphorylation due to cytosolic calcium overload was revealed in this paper. It was also demonstrated that autophagic protein aggregates degradation blockade accompanied by impaired autophagy correlated positively with intra-acinar cell digestive aymogen activation stimulated by cerulein or L-arginine. The role of spautin-1 in ameliorating acute pancreatitis was shown here to be associated with impaired autophagy inhibition and Ca2+ overload alleviation. We provide a promising therapy for acute pancreatitis through targeting both impaired autophagy and increased cytosolic calcium. PMID:27579473

  8. Acute myocardial infarction and cardiogenic shock: pharmacologic and mechanical hemodynamic support pathways.

    PubMed

    Graf, Tobias; Desch, Steffen; Eitel, Ingo; Thiele, Holger

    2015-09-01

    Cardiogenic shock (CS) is still the predominant cause of in-hospital death in patients with acute myocardial infarction, although mortality has been reduced in recent years. Early percutaneous coronary intervention and coronary artery bypass grafting are causal therapies implemented in CS, supported by catecholamines, fluids, intra-aortic balloon pumping, and also active percutaneous assist devices. There is only limited evidence from randomized studies of any of these treatments in CS, except for early revascularization and the relative ineffectiveness of intra-aortic balloon pumping. This review will present treatment pathways of CS complicating acute myocardial infarction, with a major focus on revascularization, intensive care unit treatment, and mechanical support devices.

  9. 21 CFR 320.28 - Correlation of bioavailability with an acute pharmacological effect or clinical evidence.

    Code of Federal Regulations, 2010 CFR

    2010-04-01

    ... 21 Food and Drugs 5 2010-04-01 2010-04-01 false Correlation of bioavailability with an acute..., DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) DRUGS FOR HUMAN USE BIOAVAILABILITY AND BIOEQUIVALENCE REQUIREMENTS Procedures for Determining the Bioavailability or Bioequivalence of Drug Products §...

  10. Alterations in cellular metabolome after pharmacological inhibition of Notch in glioblastoma cells.

    PubMed

    Kahlert, Ulf D; Cheng, Menglin; Koch, Katharina; Marchionni, Luigi; Fan, Xing; Raabe, Eric H; Maciaczyk, Jarek; Glunde, Kristine; Eberhart, Charles G

    2016-03-01

    Notch signaling can promote tumorigenesis in the nervous system and plays important roles in stem-like cancer cells. However, little is known about how Notch inhibition might alter tumor metabolism, particularly in lesions arising in the brain. The gamma-secretase inhibitor MRK003 was used to treat glioblastoma neurospheres, and they were subdivided into sensitive and insensitive groups in terms of canonical Notch target response. Global metabolomes were then examined using proton magnetic resonance spectroscopy, and changes in intracellular concentration of various metabolites identified which correlate with Notch inhibition. Reductions in glutamate were verified by oxidation-based colorimetric assays. Interestingly, the alkylating chemotherapeutic agent temozolomide, the mTOR-inhibitor MLN0128, and the WNT inhibitor LGK974 did not reduce glutamate levels, suggesting that changes to this metabolite might reflect specific downstream effects of Notch blockade in gliomas rather than general sequelae of tumor growth inhibition. Global and targeted expression analyses revealed that multiple genes important in glutamate homeostasis, including glutaminase, are dysregulated after Notch inhibition. Treatment with an allosteric inhibitor of glutaminase, compound 968, could slow glioblastoma growth, and Notch inhibition may act at least in part by regulating glutaminase and glutamate.

  11. Pharmacologic inhibition of ghrelin receptor signaling is insulin sparing and promotes insulin sensitivity.

    PubMed

    Longo, Kenneth A; Govek, Elizabeth K; Nolan, Anna; McDonagh, Thomas; Charoenthongtrakul, Soratree; Giuliana, Derek J; Morgan, Kristen; Hixon, Jeffrey; Zhou, Chaoseng; Kelder, Bruce; Kopchick, John J; Saunders, Jeffrey O; Navia, Manuel A; Curtis, Rory; DiStefano, Peter S; Geddes, Brad J

    2011-10-01

    Ghrelin influences a variety of metabolic functions through a direct action at its receptor, the GhrR (GhrR-1a). Ghrelin knockout (KO) and GhrR KO mice are resistant to the negative effects of high-fat diet (HFD) feeding. We have generated several classes of small-molecule GhrR antagonists and evaluated whether pharmacologic blockade of ghrelin signaling can recapitulate the phenotype of ghrelin/GhrR KO mice. Antagonist treatment blocked ghrelin-induced and spontaneous food intake; however, the effects on spontaneous feeding were absent in GhrR KO mice, suggesting target-specific effects of the antagonists. Oral administration of antagonists to HFD-fed mice improved insulin sensitivity in both glucose tolerance and glycemic clamp tests. The insulin sensitivity observed was characterized by improved glucose disposal with dramatically decreased insulin secretion. It is noteworthy that these results mimic those obtained in similar tests of HFD-fed GhrR KO mice. HFD-fed mice treated for 56 days with antagonist experienced a transient decrease in food intake but a sustained body weight decrease resulting from decreased white adipose, but not lean tissue. They also had improved glucose disposal and a striking reduction in the amount of insulin needed to achieve this. These mice had reduced hepatic steatosis, improved liver function, and no evidence of systemic toxicity relative to controls. Furthermore, GhrR KO mice placed on low- or high-fat diets had lifespans similar to the wild type, emphasizing the long-term safety of ghrelin receptor blockade. We have therefore demonstrated that chronic pharmacologic blockade of the GhrR is an effective and safe strategy for treating metabolic syndrome.

  12. Pharmacological characterization of histone deacetylase inhibitor and tumor cell-growth inhibition properties of new benzofuranone compounds.

    PubMed

    Blanquart, C; François, M; Charrier, C; Bertrand, P; Gregoire, M

    2011-10-01

    Epigenetic modifications, such as DNA methylation or histone deacetylation, are early events in cell tumorigenesis. The consequences of these modifications are repression of gene transcription and, notably, of tumor suppressor gene transcription. New therapeutic strategies aim to 'normalize' the epigenetic status of cancer cells. Histone deacetylase inhibitors (HDACi) have shown promising effects against proliferation and resistance to apoptosis of a large number of cancer cells. Vorinostat (SAHA), a hydroxamate HDACi, has been approved by the U.S. Food and Drug Administration (FDA) for the treatment of refractory cutaneous T-cell lymphoma (CTCL). However, HDACi are poorly specific, present toxicities and many have very low half-lives in the plasma. Thus, the development of new compounds is necessary in order to increase the potential of HDACi in cancer treatment. We designed an assay, based on bioluminescence resonance energy transfer (BRET) technology, to screen and characterize HDACi activity in living cells. Using our specific and reproducible BRET assay, we characterized the pharmacological properties of benzofuranone HDACi compounds for the induction of histone acetylation and performed a comparison with the properties of suberoylanilide hydroxamic acid (SAHA) and valproic acid (VPA). We defined a benzofuranone HDACi compound that induced histone acetylation at nanomolar concentrations and showed an increased duration of histone acetylation. These properties correlated with the pharmacological properties of this HDACi for the growth inhibition of cancer cells. We, thus, demonstrated the applicability of BRET technology for the screening and characterization of new HDACi compounds in living cells, and identified an interesting benzofuranone HDACi.

  13. Genetic and pharmacological inhibition of CDK9 drives neutrophil apoptosis to resolve inflammation in zebrafish in vivo

    PubMed Central

    Hoodless, Laura J.; Lucas, Christopher D.; Duffin, Rodger; Denvir, Martin A.; Haslett, Christopher; Tucker, Carl S.; Rossi, Adriano G.

    2016-01-01

    Neutrophilic inflammation is tightly regulated and subsequently resolves to limit tissue damage and promote repair. When the timely resolution of inflammation is dysregulated, tissue damage and disease results. One key control mechanism is neutrophil apoptosis, followed by apoptotic cell clearance by phagocytes such as macrophages. Cyclin-dependent kinase (CDK) inhibitor drugs induce neutrophil apoptosis in vitro and promote resolution of inflammation in rodent models. Here we present the first in vivo evidence, using pharmacological and genetic approaches, that CDK9 is involved in the resolution of neutrophil-dependent inflammation. Using live cell imaging in zebrafish with labelled neutrophils and macrophages, we show that pharmacological inhibition, morpholino-mediated knockdown and CRISPR/cas9-mediated knockout of CDK9 enhances inflammation resolution by reducing neutrophil numbers via induction of apoptosis after tailfin injury. Importantly, knockdown of the negative regulator La-related protein 7 (LaRP7) increased neutrophilic inflammation. Our data show that CDK9 is a possible target for controlling resolution of inflammation. PMID:27833165

  14. The pharmacological mechanism of angiotensin-converting enzyme inhibition by green tea, Rooibos and enalaprilat - a study on enzyme kinetics.

    PubMed

    Persson, Ingrid A-L

    2012-04-01

    Green tea (Camellia sinensis L.) and Rooibos (Aspalathus linearis Dahlg.) inhibit angiotensin-converting enzyme (ACE) in vitro and in vivo. The ACE inhibitor enalaprilat has been described previously as a competitive inhibitor and sometimes as a non-competitive inhibitor. The aim of this study was to investigate the pharmacological mechanism of ACE inhibition of green tea and Rooibos by enzyme kinetics, and to compare this with enalaprilat. A Michaelis-Menten kinetics and Lineweaver-Burk graph showed mean values of V(max)  = 3.73 µM and K(m)  = 0.71 µM for green tea, of V(max)  = 6.76 µM and K(m)  = 0.78 µM for Rooibos, of V(max)  = 12.54 µM and K(m)  = 2.77 µM for enalaprilat, and of V(max)  = 51.33 µM and K(m)  = 9.22 µM for the PBS control. Incubating serum with green tea or Rooibos saturated with zinc chloride did not change the inhibitory effect. Enalaprilat preincubated with zinc chloride showed a decrease in the inhibitory effect. In conclusion, green tea, Rooibos and enalaprilat seem to inhibit ACE activity using a mixed inhibitor mechanism.

  15. Pharmacological BACE1 and BACE2 inhibition induces hair depigmentation by inhibiting PMEL17 processing in mice

    PubMed Central

    Shimshek, Derya R.; Jacobson, Laura H.; Kolly, Carine; Zamurovic, Natasa; Balavenkatraman, Kamal Kumar; Morawiec, Laurent; Kreutzer, Robert; Schelle, Juliane; Jucker, Mathias; Bertschi, Barbara; Theil, Diethilde; Heier, Annabelle; Bigot, Karine; Beltz, Karen; Machauer, Rainer; Brzak, Irena; Perrot, Ludovic; Neumann, Ulf

    2016-01-01

    Melanocytes of the hair follicle produce melanin and are essential in determining the differences in hair color. Pigment cell-specific MELanocyte Protein (PMEL17) plays a crucial role in melanogenesis. One of the critical steps is the amyloid-like functional oligomerization of PMEL17. Beta Site APP Cleaving Enzyme-2 (BACE2) and γ-secretase have been shown to be key players in generating the proteolytic fragments of PMEL17. The β-secretase (BACE1) is responsible for the generation of amyloid-β (Aβ) fragments in the brain and is therefore proposed as a therapeutic target for Alzheimer’s disease (AD). Currently BACE1 inhibitors, most of which lack selectivity over BACE2, have demonstrated efficacious reduction of amyloid-β peptides in animals and the CSF of humans. BACE2 knock-out mice have a deficiency in PMEL17 proteolytic processing leading to impaired melanin storage and hair depigmentation. Here, we confirm BACE2-mediated inhibition of PMEL17 proteolytic processing in vitro in mouse and human melanocytes. Furthermore, we show that wildtype as well as bace2+/− and bace2−/− mice treated with a potent dual BACE1/BACE2 inhibitor NB-360 display dose-dependent appearance of irreversibly depigmented hair. Retinal pigmented epithelium showed no morphological changes. Our data demonstrates that BACE2 as well as additional BACE1 inhibition affects melanosome maturation and induces hair depigmentation in mice. PMID:26912421

  16. Pharmacological BACE1 and BACE2 inhibition induces hair depigmentation by inhibiting PMEL17 processing in mice.

    PubMed

    Shimshek, Derya R; Jacobson, Laura H; Kolly, Carine; Zamurovic, Natasa; Balavenkatraman, Kamal Kumar; Morawiec, Laurent; Kreutzer, Robert; Schelle, Juliane; Jucker, Mathias; Bertschi, Barbara; Theil, Diethilde; Heier, Annabelle; Bigot, Karine; Beltz, Karen; Machauer, Rainer; Brzak, Irena; Perrot, Ludovic; Neumann, Ulf

    2016-02-25

    Melanocytes of the hair follicle produce melanin and are essential in determining the differences in hair color. Pigment cell-specific MELanocyte Protein (PMEL17) plays a crucial role in melanogenesis. One of the critical steps is the amyloid-like functional oligomerization of PMEL17. Beta Site APP Cleaving Enzyme-2 (BACE2) and γ-secretase have been shown to be key players in generating the proteolytic fragments of PMEL17. The β-secretase (BACE1) is responsible for the generation of amyloid-β (Aβ) fragments in the brain and is therefore proposed as a therapeutic target for Alzheimer's disease (AD). Currently BACE1 inhibitors, most of which lack selectivity over BACE2, have demonstrated efficacious reduction of amyloid-β peptides in animals and the CSF of humans. BACE2 knock-out mice have a deficiency in PMEL17 proteolytic processing leading to impaired melanin storage and hair depigmentation. Here, we confirm BACE2-mediated inhibition of PMEL17 proteolytic processing in vitro in mouse and human melanocytes. Furthermore, we show that wildtype as well as bace2(+/-) and bace2(-/-) mice treated with a potent dual BACE1/BACE2 inhibitor NB-360 display dose-dependent appearance of irreversibly depigmented hair. Retinal pigmented epithelium showed no morphological changes. Our data demonstrates that BACE2 as well as additional BACE1 inhibition affects melanosome maturation and induces hair depigmentation in mice.

  17. Novel pharmacologic treatment in acute binge eating disorder – role of lisdexamfetamine

    PubMed Central

    Guerdjikova, Anna I; Mori, Nicole; Casuto, Leah S; McElroy, Susan L

    2016-01-01

    Binge eating disorder (BED) is the most common eating disorder and an important public health problem. It is characterized by recurrent episodes of excessive food consumption accompanied by a sense of loss of control over the binge eating behavior without the inappropriate compensatory weight loss behaviors of bulimia nervosa. BED affects both sexes and all age groups and is associated with medical and psychiatric comorbidities. Until recently, self-help and psychotherapy were the primary treatment options for patients with BED. In early 2015, lisdexamfetamine dimesylate, a prodrug stimulant marketed for attention deficit hyperactive disorder, was the first pharmacologic agent to be approved by the US Food and Drug Administration for the treatment of moderate or severe BED in adults. This article summarizes BED clinical presentation, and discusses the pharmacokinetic profile, efficacy, and safety of lisdexamfetamine dimesylate in the treatment of BED in adults. PMID:27143885

  18. Pharmacological inhibition of S-nitrosoglutathione reductase improves endothelial vasodilatory function in rats in vivo

    PubMed Central

    Chen, Qiumei; Sievers, Richard E.; Varga, Monika; Kharait, Sourabh; Haddad, Daniel J.; Patton, Aaron K.; Delany, Christopher S.; Mutka, Sarah C.; Blonder, Joan P.; Dubé, Gregory P.; Rosenthal, Gary J.

    2013-01-01

    Nitric oxide (NO) exerts a wide range of cellular effects in the cardiovascular system. NO is short lived, but S-nitrosoglutathione (GSNO) functions as a stable intracellular bioavailable NO pool. Accordingly, increased levels can facilitate NO-mediated processes, and conversely, catabolism of GSNO by the regulatory enzyme GSNO reductase (GSNOR) can impair these processes. Because dysregulated GSNOR can interfere with processes relevant to cardiovascular health, it follows that inhibition of GSNOR may be beneficial. However, the effect of GSNOR inhibition on vascular activity is unknown. To study the effects of GSNOR inhibition on endothelial function, we treated rats with a small-molecule inhibitor of GSNOR (N6338) that has vasodilatory effects on isolated aortic rings and assessed effects on arterial flow-mediated dilation (FMD), an NO-dependent process. GSNOR inhibition with a single intravenous dose of N6338 preserved FMD (15.3 ± 5.4 vs. 14.2 ± 6.3%, P = nonsignificant) under partial NO synthase inhibition that normally reduces FMD by roughly 50% (14.1 ± 2.9 vs. 7.6 ± 4.4%, P < 0.05). In hypertensive rats, daily oral administration of N6338 for 14 days reduced blood pressure (170.0 ± 5.3/122.7 ± 6.4 vs. 203.8 ± 1.9/143.7 ± 7.5 mmHg for vehicle, P < 0.001) and vascular resistance index (1.5 ± 0.4 vs. 3.2 ± 1.0 mmHg·min·l−1 for vehicle, P < 0.001), and restored FMD from an initially impaired state (7.4 ± 1.7%, day 0) to a level (13.0 ± 3.1%, day 14, P < 0.001) similar to that observed in normotensive rats. N6338 also reversed the pathological kidney changes exhibited by the hypertensive rats. GSNOR inhibition preserves FMD under conditions of impaired NO production and protects against both microvascular and conduit artery dysfunction in a model of hypertension. PMID:23349456

  19. Reconciling the role of serotonin in behavioral inhibition and aversion: acute tryptophan depletion abolishes punishment-induced inhibition in humans.

    PubMed

    Crockett, Molly J; Clark, Luke; Robbins, Trevor W

    2009-09-23

    The neuromodulator serotonin has been implicated in a large number of affective and executive functions, but its precise contribution to motivation remains unclear. One influential hypothesis has implicated serotonin in aversive processing; another has proposed a more general role for serotonin in behavioral inhibition. Because behavioral inhibition is a prepotent reaction to aversive outcomes, it has been a challenge to reconcile these two accounts. Here, we show that serotonin is critical for punishment-induced inhibition but not overall motor response inhibition or reporting aversive outcomes. We used acute tryptophan depletion to temporarily lower brain serotonin in healthy human volunteers as they completed a novel task designed to obtain separate measures of motor response inhibition, punishment-induced inhibition, and sensitivity to aversive outcomes. After a placebo treatment, participants were slower to respond under punishment conditions compared with reward conditions. Tryptophan depletion abolished this punishment-induced inhibition without affecting overall motor response inhibition or the ability to adjust response bias in line with punishment contingencies. The magnitude of reduction in punishment-induced inhibition depended on the degree to which tryptophan depletion reduced plasma tryptophan levels. These findings extend and clarify previous research on the role of serotonin in aversive processing and behavioral inhibition and fit with current theorizing on the involvement of serotonin in predicting aversive outcomes.

  20. Halogenated pyrrolopyrimidine analogues of adenosine from marine organisms: pharmacological activities and potent inhibition of adenosine kinase.

    PubMed

    Davies, L P; Jamieson, D D; Baird-Lambert, J A; Kazlauskas, R

    1984-02-01

    Two novel halogenated pyrrolopyrimidine analogues of adenosine, isolated from marine sources, have been examined for pharmacological and biochemical activities. 4-Amino-5-bromo-pyrrolo[2,3-d]pyrimidine, from a sponge of the genus Echinodictyum, had bronchodilator activity at least as potent as theophylline but with a different biochemical profile; unlike theophylline it had no antagonist activity at CNS adenosine receptors and it was quite a potent inhibitor of adenosine uptake and adenosine kinase in brain tissue. 5'-Deoxy-5-iodotubercidin, isolated from the red alga Hypnea valentiae, caused potent muscle relaxation and hypothermia when injected into mice. This compound was a very potent inhibitor of adenosine uptake into rat and guinea-pig brain slices and an extremely potent inhibitor of adenosine kinase from guinea-pig brain and rat brain and liver. Neither of these two pyrrolopyrimidine analogues was a substrate for, or an inhibitor of, adenosine deaminase. Neither compound appeared to have any direct agonist activity on guinea-pig brain adenosine-stimulated adenylate cyclase (A2 adenosine receptors). 5'-Deoxy-5-iodotubercidin is unique in two respects: it appears to be the first naturally-occurring example of a 5'-deoxyribosyl nucleoside and is the first example of a specifically iodinated nucleoside from natural sources. It may be the most potent adenosine kinase inhibitor yet described and, by virtue of its structure, may prove to be the most specific.

  1. Contrasting effects of presynaptic alpha2-adrenergic autoinhibition and pharmacologic augmentation of presynaptic inhibition on sympathetic heart rate control.

    PubMed

    Miyamoto, Tadayoshi; Kawada, Toru; Yanagiya, Yusuke; Akiyama, Tsuyoshi; Kamiya, Atsunori; Mizuno, Masaki; Takaki, Hiroshi; Sunagawa, Kenji; Sugimachi, Masaru

    2008-11-01

    Presynaptic alpha2-adrenergic receptors are known to exert feedback inhibition on norepinephrine release from the sympathetic nerve terminals. To elucidate the dynamic characteristics of the inhibition, we stimulated the right cardiac sympathetic nerve according to a binary white noise signal while measuring heart rate (HR) in anesthetized rabbits (n = 6). We estimated the transfer function from cardiac sympathetic nerve stimulation to HR and the corresponding step response of HR, with and without the blockade of presynaptic inhibition by yohimbine (1 mg/kg followed by 0.1 mg.kg(-1).h(-1) iv). We also examined the effect of the alpha2-adrenergic receptor agonist clonidine (0.3 and 1.5 mg.kg(-1).h(-1) iv) in different rabbits (n = 5). Yohimbine increased the maximum step response (from 7.2 +/- 0.8 to 12.2 +/- 1.7 beats/min, means +/- SE, P < 0.05) without significantly affecting the initial slope (0.93 +/- 0.23 vs. 0.94 +/- 0.22 beats.min(-1).s(-1)). Higher dose but not lower dose clonidine significantly decreased the maximum step response (from 6.3 +/- 0.8 to 6.8 +/- 1.0 and 2.8 +/- 0.5 beats/min, P < 0.05) and also reduced the initial slope (from 0.56 +/- 0.07 to 0.51 +/- 0.04 and 0.22 +/- 0.06 beats.min(-1).s(-1), P < 0.05). Our findings indicate that presynaptic alpha2-adrenergic autoinhibition limits the maximum response without significantly compromising the rapidity of effector response. In contrast, pharmacologic augmentation of the presynaptic inhibition not only attenuates the maximum response but also results in a sluggish effector response.

  2. Pharmacological inhibition of PHOSPHO1 suppresses vascular smooth muscle cell calcification.

    PubMed

    Kiffer-Moreira, Tina; Yadav, Manisha C; Zhu, Dongxing; Narisawa, Sonoko; Sheen, Campbell; Stec, Boguslaw; Cosford, Nicholas D; Dahl, Russell; Farquharson, Colin; Hoylaerts, Marc F; Macrae, Vicky E; Millán, José Luis

    2013-01-01

    Medial vascular calcification (MVC) is common in patients with chronic kidney disease, obesity, and aging. MVC is an actively regulated process that resembles skeletal mineralization, resulting from chondro-osteogenic transformation of vascular smooth muscle cells (VSMCs). Here, we used mineralizing murine VSMCs to study the expression of PHOSPHO1, a phosphatase that participates in the first step of matrix vesicles-mediated initiation of mineralization during endochondral ossification. Wild-type (WT) VSMCs cultured under calcifying conditions exhibited increased Phospho1 gene expression and Phospho1(-/-) VSMCs failed to mineralize in vitro. Using natural PHOSPHO1 substrates, potent and specific inhibitors of PHOSPHO1 were identified via high-throughput screening and mechanistic analysis and two of these inhibitors, designated MLS-0390838 and MLS-0263839, were selected for further analysis. Their effectiveness in preventing VSMC calcification by targeting PHOSPHO1 function was assessed, alone and in combination with a potent tissue-nonspecific alkaline phosphatase (TNAP) inhibitor MLS-0038949. PHOSPHO1 inhibition by MLS-0263839 in mineralizing WT cells (cultured with added inorganic phosphate) reduced calcification in culture to 41.8% ± 2.0% of control. Combined inhibition of PHOSPHO1 by MLS-0263839 and TNAP by MLS-0038949 significantly reduced calcification to 20.9% ± 0.74% of control. Furthermore, the dual inhibition strategy affected the expression of several mineralization-related enzymes while increasing expression of the smooth muscle cell marker Acta2. We conclude that PHOSPHO1 plays a critical role in VSMC mineralization and that "phosphatase inhibition" may be a useful therapeutic strategy to reduce MVC.

  3. Acute inhibition of corticosteroidogenesis by inhibitors of calmodulin action.

    PubMed

    Carsia, R V; Moyle, W R; Wolff, D J; Malamed, S

    1982-11-01

    To identify the possible role of calmodulin in ACTH function, we tested the ability of chlorpromazine (CP) and other calmodulin antagonists to inhibit steroidogenesis of isolated adrenocortical cells of the rat. CP reversibly inhibited maximal ACTH-induced corticosterone (B) production. The presence of the drug did not alter the ED50 of ACTH stimulation (3.2 X 10(3) pg/ml), suggesting that it inhibited ACTH-induced steroidogenesis in a noncompetitive manner. The CP concentration required for half-maximal inhibition was 8.2 microM, a value close to the dissociation constant of the CP-calmodulin complex (5.3 microM). Concentrations greater than 40 microM resulted in complete inhibition. Similar concentrations of CP inhibited ACTH-induced cAMP accumulation in a dose-dependent manner, indicating an effect of the drug on early events in ACTH action. In addition, CP also apparently acted at a site distal to the point of cAMP formation, as shown by the finding that it inhibited cAMP-induced B production. CP inhibition of ACTH-induced B production was independent of the Ca2+ concentration, suggesting that the drug did not compete with Ca2+ directly. Concentrations of CP greater than 20 microM inhibited protein synthesis as measured by leucine incorporation into cellular proteins. Thus, although the inhibitory effect of high concentrations of CP on steroidogenesis might be explained by an effect on protein synthesis, the inhibition seen at 10 microM appeared to be independent of protein synthesis. Other antagonists of calmodulin action inhibited maximal ACTH-induced B production with the following relative potencies: trifluoperazine greater than CP greater than haloperidol greater than chlordiazepoxide. This order is similar to that reported for inhibition of calmodulin-activated phosphodiesterase and for binding to calmodulin. These findings suggest that calmodulin may modulate the effect of ACTH on steroidogenesis at multiple sites.

  4. Pharmacological inhibition of KIT activates MET signaling in gastrointestinal stromal tumors

    PubMed Central

    Cohen, Noah A.; Zeng, Shan; Seifert, Adrian M.; Kim, Teresa S.; Sorenson, Eric C.; Greer, Jonathan B.; Beckman, Michael J.; Santamaria-Barria, Juan A.; Crawley, Megan H.; Green, Benjamin L.; Rossi, Ferdinand; Besmer, Peter; Antonescu, Cristina R.; DeMatteo, Ronald P.

    2015-01-01

    Gastrointestinal stromal tumors (GIST) are the most common adult sarcomas and the oncogenic driver is usually a KIT or PDGFRA mutation. While GIST are often initially sensitive to imatinib or other tyrosine kinase inhibitors, resistance generally develops necessitating backup strategies for therapy. In this study, we determined that a subset of human GIST specimens that acquired imatinib resistance acquired expression of activated forms of the MET oncogene. MET activation also developed after imatinib therapy in a mouse model of GIST (KitV558del/+ mice), where it was associated with increased tumor hypoxia. MET activation also occurred in imatinib-sensitive human GIST cell lines after imatinib treatment in vitro. MET inhibition by crizotinib or RNA interference was cytotoxic to an imatinib-resistant human GIST cell population. Moreover, combining crizotinib and imatinib was more effective than imatinib alone in imatinib-sensitive GIST models. Lastly, cabozantinib, a dual MET and KIT small molecule inhibitor, was markedly more effective than imatinib in multiple preclinical models of imatinib-sensitive and imatinib-resistant GIST. Collectively, our findings showed that activation of compensatory MET signaling by KIT inhibition may contribute to tumor resistance. Furthermore, our work offered a preclinical proof of concept for MET inhibition by cabozantinib as an effective strategy for GIST treatment. PMID:25836719

  5. Systems pharmacology modeling of drug‐induced hyperbilirubinemia: Differentiating hepatotoxicity and inhibition of enzymes/transporters

    PubMed Central

    Battista, C; Woodhead, JL; Stahl, SH; Mettetal, JT; Watkins, PB; Siler, SQ; Howell, BA

    2017-01-01

    Elevations in serum bilirubin during drug treatment may indicate global liver dysfunction and a high risk of liver failure. However, drugs also can increase serum bilirubin in the absence of hepatic injury by inhibiting specific enzymes/transporters. We constructed a mechanistic model of bilirubin disposition based on known functional polymorphisms in bilirubin metabolism/transport. Using physiologically based pharmacokinetic (PBPK) model‐predicted drug exposure and enzyme/transporter inhibition constants determined in vitro, our model correctly predicted indinavir‐mediated hyperbilirubinemia in humans and rats. Nelfinavir was predicted not to cause hyperbilirubinemia, consistent with clinical observations. We next examined a new drug candidate that caused both elevations in serum bilirubin and biochemical evidence of liver injury in rats. Simulations suggest that bilirubin elevation primarily resulted from inhibition of transporters rather than global liver dysfunction. We conclude that mechanistic modeling of bilirubin can help elucidate underlying mechanisms of drug‐induced hyperbilirubinemia, and thereby distinguish benign from clinically important elevations in serum bilirubin. PMID:28074467

  6. Acute pharmacologically induced shifts in serotonin availability abolish emotion-selective responses to negative face emotions in distinct brain networks.

    PubMed

    Grady, Cheryl L; Siebner, Hartwig R; Hornboll, Bettina; Macoveanu, Julian; Paulson, Olaf B; Knudsen, Gitte M

    2013-05-01

    Pharmacological manipulation of serotonin availability can alter the processing of facial expressions of emotion. Using a within-subject design, we measured the effect of serotonin on the brain's response to aversive face emotions with functional MRI while 20 participants judged the gender of neutral, fearful and angry faces. In three separate and counterbalanced sessions, participants received citalopram (CIT) to raise serotonin levels, underwent acute tryptophan depletion (ATD) to lower serotonin, or were studied without pharmacological challenge (Control). An analysis designed to identify distributed brain responses identified two brain networks with modulations of activity related to face emotion and serotonin level. The first network included the left amygdala, bilateral striatum, and fusiform gyri. During the Control session this network responded only to fearful faces; increasing serotonin decreased this response to fear, whereas reducing serotonin enhanced the response of this network to angry faces. The second network involved bilateral amygdala and ventrolateral prefrontal cortex, and these regions also showed increased activity to fear during the Control session. Both drug challenges enhanced the neural response of this set of regions to angry faces, relative to Control, and CIT also enhanced activity for neutral faces. The net effect of these changes in both networks was to abolish the selective response to fearful expressions. These results suggest that a normal level of serotonin is critical for maintaining a differentiated brain response to threatening face emotions. Lower serotonin leads to a broadening of a normally fear-specific response to anger, and higher levels reduce the differentiated brain response to aversive face emotions.

  7. Pharmacological interaction with the sigma1 (σ1)-receptor in the acute behavioral effects of antidepressants.

    PubMed

    Villard, Vanessa; Meunier, Johann; Chevallier, Nathalie; Maurice, Tangui

    2011-01-01

    Selective agonists of the sigma-1 (σ(1)) ligand-operated chaperone protein, like igmesine or PRE-084, are antidepressants in preclinical depression models. σ(1)-Protein activation may contribute to the antidepressant efficacy of drugs known to act as selective serotonin-reuptake inhibitors (SSRI) or noradrenaline reuptake inhibitors through direct or indirect involvement of the σ(1)-receptor in the drug effect. We here compared antidepressant effects in two behavioral procedures, the forced swimming test (FST) and conditioned fear stress (CFS). The involvement of the σ(1)-receptor was examined using a co-treatment with the σ(1)-antagonist BD1047 or using σ(1)-knockout (KO) mice. Igmesine but not PRE-084 decreased FST immobility. The SSRI fluoxetine and sertraline, but not fluvoxamine, and the tricyclic antidepressants imipramine, desipramine, and amitriptyline were also effective. Only the effect of igmesine was blocked by BD1047 or in σ(1)-KO mice. Igmesine, PRE-084, fluvoxamine, and sertraline decreased the CFS immobility in a BD1047- and σ(1)-KO-sensitive manner. Among tricyclics, only amitriptyline was effective and its effect was unaffected by BD1047 or in σ(1)-KO mice. The behavioral effects induced by mixed σ(1)-receptor/SSRI antidepressants, like fluvoxamine or sertraline, may therefore involve a non-selective action at both targets. Moreover, the CFS appears to more reliably uncover a σ(1) pharmacological component in antidepressant screening.

  8. Pharmacological brain cooling with indomethacin in acute hemorrhagic stroke: antiinflammatory cytokines and antioxidative effects.

    PubMed

    Dohi, K; Jimbo, H; Ikeda, Y; Fujita, S; Ohtaki, H; Shioda, S; Abe, T; Aruga, T

    2006-01-01

    We evaluated the effects of a novel pharmacological brain cooling (PBC) method with indomethacin (IND), a nonselective cyclooxygenase inhibitor, without the use of cooling blankets in patients with hemorrhagic stroke. Forty-six patients with hemorrhagic stroke (subarachnoid hemorrhage; n = 35, intracerebral hemorrhage; n = 11) were enrolled in this study. Brain temperature was measured directly with a temperature sensor. Patients were cooled by administering transrectal IND (100 mg) and a modified nasopharyngeal cooling method (positive selective brain cooling) initially. Brain temperature was controlled with IND 6 mg/kg/day for 14 days. Cerebrospinal fluid concentrations of interleukin-1beta (CSF IL-1beta) and serum bilirubin levels were measured at 1, 2, 4, and 7 days. The incidence of complicating symptomatic vasospasm after subarachnoid hemorrhage was lower than in non-PBC patients. CSF IL-1beta and serum bilirubin levels were suppressed in treated patients. IND has several beneficial effects on damaged brain tissues (anticytokine, free radical scavenger, antiprostaglandin effects, etc.) and prevents initial and secondary brain damage. PBC treatment for hemorrhagic stroke in patients appears to yield favorable results by acting as an antiinflammatory cytokine and reducing oxidative stress.

  9. Corticofugal outputs facilitate acute, but inhibit chronic pain in rats.

    PubMed

    Wang, Ning; Wang, Jin-Yan; Luo, Fei

    2009-03-01

    It has been widely accepted that the primary somatosensory cortex (SI) plays an essential role in the sensory-discriminative aspect of pain perception. However, it remains unclear whether the SI has a role in the descending modulation of pain. Although there are abundant fibers projecting back from sensory cortex to thalamic nuclei, and the influence of cortical modulation from SI on the thalamic nociceptive relay neurons has been addressed, little is known about how the cortical outputs modulate the nociceptive behaviors resulting from tissue injury or evoked by painful stimulation. The present study was designed to test whether the cortical outputs influenced the nociceptive behaviors using rat models of noxious thermal-induced acute pain, formalin-induced acute and CFA-evoked chronic inflammatory pain. The results showed that intracortical microinjection of GABAA agonist muscimol significantly reduced the first and second phase behaviors in formalin tests and elevated the nociceptive thresholds in the thermal stimulus-elicited acute pain, suggesting a facilitatory influence of SI on the acute pain sensation. By contrast, microinjection of GABAA antagonist bicuculline remarkably reduced the thermal hyperalgesia of the CFA-inflamed hindpaws, indicating an inhibitory effect of SI output in the chronic pain state. The opposite modulatory effects in acute and chronic pain states suggest that there exists a functional switch for the SI cortex at different stages of pain disease, which is of great significance for the biological adaptation.

  10. Pharmacological evaluation of alcohol withdrawal-induced inhibition of exploratory behaviour and supersensitivity to harmine-induced tremor.

    PubMed

    Meert, T F

    1994-01-01

    Rats given a liquid diet containing 10% (v/v) alcohol consume high quantities of alcohol. Within 8 hr after cessation of the alcohol intake, the animals will show alcohol-withdrawal reactions including a supersensitivity to harmine-induced tremor and an inhibition of exploratory behaviour in a neutral environment. Several drugs can overcome one or more of these alcohol-withdrawal reactions. A reduction of the alcohol withdrawal-induced inhibition of exploration, in terms of both the number of transits into the open field and the time spent in the open field, was obtained with chlordiazepoxide, ritanserin, mianserin and propranolol. Of these four compounds, propranolol and mianserin were also active against the supersensitivity to both 5.00 and 10.00 mg/kg harmine-induced tremor. Chlordiazepoxide and ritanserin were only active against 5.00 mg/kg harmine. Other compounds that reversed the supersensitivity to harmine-induced tremor during alcohol withdrawal included buspirone, fluoxetine, haloperidol, clonidine, flunarizine and baclofen. Very limited effects on both alcohol-withdrawal reactions were observed with ondansetron, nimodipine and MK-801. Risperidone and SCH 23390 were inactive. These results demonstrate that some alcohol withdrawal reactions can be studied in a systematic way and that various pharmacological agents can differentially interact with these alcohol withdrawal reactions.

  11. Pharmacological activation/inhibition of the cannabinoid system affects alcohol withdrawal-induced neuronal hypersensitivity to excitotoxic insults.

    PubMed

    Rubio, Marina; Villain, Hélène; Docagne, Fabian; Roussel, Benoit D; Ramos, José Antonio; Vivien, Denis; Fernandez-Ruiz, Javier; Ali, Carine

    2011-01-01

    Cessation of chronic ethanol consumption can increase the sensitivity of the brain to excitotoxic damages. Cannabinoids have been proposed as neuroprotectants in different models of neuronal injury, but their effect have never been investigated in a context of excitotoxicity after alcohol cessation. Here we examined the effects of the pharmacological activation/inhibition of the endocannabinoid system in an in vitro model of chronic ethanol exposure and withdrawal followed by an excitotoxic challenge. Ethanol withdrawal increased N-methyl-D-aspartate (NMDA)-evoked neuronal death, probably by altering the ratio between GluN2A and GluN2B NMDA receptor subunits. The stimulation of the endocannabinoid system with the cannabinoid agonist HU-210 decreased NMDA-induced neuronal death exclusively in ethanol-withdrawn neurons. This neuroprotection could be explained by a decrease in NMDA-stimulated calcium influx after the administration of HU-210, found exclusively in ethanol-withdrawn neurons. By contrast, the inhibition of the cannabinoid system with the CB1 receptor antagonist rimonabant (SR141716) during ethanol withdrawal increased death of ethanol-withdrawn neurons without any modification of NMDA-stimulated calcium influx. Moreover, chronic administration of rimonabant increased NMDA-stimulated toxicity not only in withdrawn neurons, but also in control neurons. In summary, we show for the first time that the stimulation of the endocannabinoid system is protective against the hyperexcitability developed during alcohol withdrawal. By contrast, the blockade of the endocannabinoid system is highly counterproductive during alcohol withdrawal.

  12. SYNERGISM FROM COMBINED IMMUNOLOGIC AND PHARMACOLOGIC INHIBITION OF HER2 IN VIVO

    PubMed Central

    Morse, Michael A.; Wei, Junping; Hartman, Zachary; Xia, Wenle; Ren, Xiu-Rong; Lei, Gangjun; Barry, William T.; Osada, Takuya; Hobeika, Amy C.; Peplinski, Sharon; Jiang, Haixiang; Devi, Gayathri R.; Chen, Wei; Spector, Neil; Amalfitano, Andrea; Lyerly, H. Kim; Clay, Timothy M.

    2009-01-01

    The monoclonal antibody trastuzumab and the EGFR/HER2 tyrosine kinase inhibitor lapatinib improve the clinical outcome of patients with HER2-overexpressing breast cancer. However, the majority of metastatic cancers will eventually progress suggesting the need for other therapies. Because HER2 overexpression persists, we hypothesized that the anti-HER2 immune response induced by cancer vaccines would be an effective strategy for treating trastuzumab and lapatinib-refractory tumors. Furthermore, we hypothesized that the antibody response could synergize with lapatinib to enhance tumor inhibition. We developed a recombinant adenoviral vector expressing a kinase-inactive HER2 (Ad-HER2-ki) to use as a cancer vaccine. Vaccine-induced polyclonal HER2-specific anti-serum was analyzed for receptor internalization and signaling effects alone and in combination with lapatinib. Ad-HER2-ki vaccine induced potent T cell and antibody responses in mice and the vaccine-induced polyclonal HER2-specific anti-serum mediated receptor internalization and degradation much more effectively than trastuzumab. Our in vitro studies demonstrated that HER2-vaccine induced antibodies effectively caused a decrease in HER2 expression, but when combined with lapatinib caused significant inhibition of HER2 signaling, decreased pERK and pAKT levels, and reduced breast tumor cell proliferation. In addition, a known mechanism of resistance to lapatinib, induction of survivin, was inhibited. The combination of Ad-HER2-ki plus lapatinib also showed superior anti-tumor efficacy in vivo. Based on these results, we feel clinical studies using this approach to target HER2-overexpressing breast cancer, including trastuzumab- and lapatinib-resistant tumors is warranted. PMID:19856307

  13. Pharmacologic retinoid signaling and physiologic retinoic acid receptor signaling inhibit basal cell carcinoma tumorigenesis

    PubMed Central

    So, Po-Lin; Fujimoto, Michele A.; Epstein, Ervin H.

    2015-01-01

    Basal cell carcinoma (BCC) is the most common human cancer. Patients with basal cell nevus syndrome (Gorlin syndrome) are highly susceptible to developing many BCCs as a result of a constitutive inactivating mutation in one allele of PATCHED 1, which encodes a tumor suppressor that is a major inhibitor of Hedgehog signaling. Dysregulated Hedgehog signaling is a common feature of both hereditary and sporadic BCCs. Recently, we showed remarkable anti-BCC chemopreventive efficacy of tazarotene, a retinoid with retinoic acid receptor (RAR) β/γ specificity, in Ptch1 +/− mice when treatment was commenced before carcinogenic insults. In this study, we assessed whether the effect of tazarotene against BCC carcinogenesis is sustained after its withdrawal and whether tazarotene is effective against preexisting microscopic BCC lesions. We found that BCCs did not reappear for at least 5 months after topical drug treatment was stopped and that already developed, microscopic BCCs were susceptible to tazarotene inhibition. In vitro, tazarotene inhibited a murine BCC keratinocyte cell line, ASZ001, suggesting that its effect in vivo is by direct action on the actual tumor cells. Down-regulation of Gli1, a target gene of Hedgehog signaling and up-regulation of CRABPII, a target gene of retinoid signaling, were observed with tazarotene treatment. Finally, we investigated the effects of topical applications of other retinoid-related compounds on BCC tumorigenesis in vivo. Tazarotene was the most effective of the preparations studied, and its effect most likely was mediated by RARγ activation. Furthermore, inhibition of basal RAR signaling in the skin promoted BCC carcinogenesis, suggesting that endogenous RAR signaling restrains BCC growth. PMID:18483315

  14. Organ Impairment—Drug–Drug Interaction Database: A Tool for Evaluating the Impact of Renal or Hepatic Impairment and Pharmacologic Inhibition on the Systemic Exposure of Drugs

    PubMed Central

    Yeung, CK; Yoshida, K; Kusama, M; Zhang, H; Ragueneau-Majlessi, I; Argon, S; Li, L; Chang, P; Le, CD; Zhao, P; Zhang, L; Sugiyama, Y; Huang, S-M

    2015-01-01

    The organ impairment and drug–drug interaction (OI-DDI) database is the first rigorously assembled database of pharmacokinetic drug exposure data from publicly available renal and hepatic impairment studies presented together with the maximum change in drug exposure from drug interaction inhibition studies. The database was used to conduct a systematic comparison of the effect of renal/hepatic impairment and pharmacologic inhibition on drug exposure. Additional applications are feasible with the public availability of this database. PMID:26380158

  15. ACUTE PHARMACOLOGICAL INHIBITION OF CHOLINESTERASE RESULTS IN MINIMAL NEUROMUSCULAR JITTER CHANGES.

    EPA Science Inventory

    Concern over the lack of available endpoints to assess peripheral nervous system dysfunction after pesticide exposure has led to the search for new laboratory models. Recently our lab adapted the in vivo clinical practice of stimulation single fiber electromyography (SFEMG) for u...

  16. Genetic knockout and pharmacologic inhibition of NCX2 cause natriuresis and hypercalciuria.

    PubMed

    Gotoh, Yusuke; Kita, Satomi; Fujii, Makoto; Tagashira, Hideaki; Horie, Ichiro; Arai, Yuji; Uchida, Shinichi; Iwamoto, Takahiro

    2015-01-09

    The Na(+)/Ca(2+) exchanger (NCX) is a bidirectional transporter that is controlled by membrane potential and transmembrane gradients of Na(+) and Ca(2+). Although two isoforms of NCX1 and NCX2 are coexpressed on the basolateral membrane of the distal nephron, the functional significance of these isoforms is not entirely clear. Therefore, we used NCX1- and NCX2-heterozygote knockout mice (KO) and their double KO, as well as isoform-selective NCX inhibitors, to determine the roles of NCX isoforms in urine formation and electrolyte excretion in mice. NCX inhibitors, particularly NCX2-sensitive inhibitors, caused a dose-dependent natriuresis and in a higher dose, moreover, hypercalciuria. Consistently, NCX1-KO possessed normal renal function similar to wild-type mice (WT), whereas NCX2-KO and double KO exhibited moderate natriuresis and hypercalciuria. Notably, renal responses to YM-244769 were equivalently observed in NCX1-KO and WT, but disappeared in NCX2-KO and double KO. Thus, functional inhibition of NCX2 initially causes natriuresis, and further inhibition of NCX2 produces hypercalciuria, suggesting that the functional significance of NCX2 lies in Na(+) and Ca(2+) reabsorption of the kidney.

  17. Pharmacological WNT Inhibition Reduces Proliferation, Survival and Clonogenicity of Glioblastoma Cells

    PubMed Central

    Kahlert, Ulf D.; Suwala, Abigail K.; Koch, Katharina; Natsumeda, Manabu; Orr, Brent A.; Hayashi, Masanori; Maciaczyk, Jarek; Eberhart, Charles G.

    2015-01-01

    Wingless (WNT) signaling has been shown to be an important pathway in gliomagenesis and in the growth of stem-like glioma cells. Using immunohistochemistry to assess translocation of β-catenin protein, we identified intranuclear staining, which suggest WNT pathway activation, in 8 of 43 (19%) adult and 9 of 30 (30%) pediatric glioblastoma patient surgical samples. WNT activity, evidenced by nuclear β-catenin in our cohort and high expression of its target AXIN2 in published glioma datasets, was associated with shorter patient survival, although this was not statistically significant. We determined the effects of the porcupine inhibitor LGK974 in 3 glioblastoma cell lines with elevated AXIN2 and found that it reduced WNT pathway activity by 50% or more as assessed by T cell factor-luciferase reporters. WNT inhibition led to suppression of growth and proliferation in the cultures and a modest induction of cell death. LGK974 reduced NANOG mRNA levels and the fraction of cells expressing the stem cell marker CD133 in neurosphere cultures, induced glial differentiation, and suppressed clonogenicity. These data indicate that LGK974 represents a promising new agent that can inhibit the canonical WNT pathway in vitro, slow tumor growth and deplete stem-like clonogenic cells, thereby providing further support for targeting WNT in patients with glioblastoma. PMID:26222502

  18. Identification, synthesis and pharmacological evaluation of novel anti-EV71 agents via cyclophilin A inhibition.

    PubMed

    Yan, Wenzhong; Qing, Jie; Mei, Hanbing; Nong, Junxiu; Huang, Jin; Zhu, Jin; Jiang, Hualiang; Liu, Lei; Zhang, Linqi; Li, Jian

    2015-12-15

    In this work, the relationship between cyclophilin A (CypA) and EV71 prompted us to screen a series of small molecular CypA inhibitors which were previously reported by our group. Among them, compounds 1 and 2 were discovered as non-immunosuppressive anti-EV71 agents with an EC50 values of 1.07±0.17μM and 3.36±0.45μM in virus assay, respectively, which were desirably for the further study. The subsequent chemical modifications derived a novel class of molecules, among which compound 11 demonstrated the most potent anti-EV71 activity in virus assay (EC50=0.37±0.17μM), and low cytotoxicity (CC50>25μM). The following CypA enzyme inhibition studies indicated that there was not only the enzyme inhibition activity, undoubtedly important, functioning in the antiviral process, but also some unknown mechanisms worked in combination, and the further study is underway in our laboratory. Nevertheless, to the best of our knowledge, compound 11 was probably the most potent small molecular anti-EV71 agent via CypA inhibitory mechanism to date. Consequently, our study provided a new potential small molecule for curing EV71 infection.

  19. Pharmacological inhibition of lipid droplet formation enhances the effectiveness of curcumin in glioblastoma.

    PubMed

    Zhang, Issan; Cui, Yiming; Amiri, Abdolali; Ding, Yidan; Campbell, Robert E; Maysinger, Dusica

    2016-03-01

    Increased lipid droplet number and fatty acid synthesis allow glioblastoma multiforme, the most common and aggressive type of brain cancer, to withstand accelerated metabolic rates and resist therapeutic treatments. Lipid droplets are postulated to sequester hydrophobic therapeutic agents, thereby reducing drug effectiveness. We hypothesized that the inhibition of lipid droplet accumulation in glioblastoma cells using pyrrolidine-2, a cytoplasmic phospholipase A2 alpha inhibitor, can sensitize cancer cells to the killing effect of curcumin, a promising anticancer agent isolated from the turmeric spice. We observed that curcumin localized in the lipid droplets of human U251N glioblastoma cells. Reduction of lipid droplet number using pyrrolidine-2 drastically enhanced the therapeutic effect of curcumin in both 2D and 3D glioblastoma cell models. The mode of cell death involved was found to be mediated by caspase-3. Comparatively, the current clinical chemotherapeutic standard, temozolomide, was significantly less effective in inducing glioblastoma cell death. Together, our results suggest that the inhibition of lipid droplet accumulation is an effective way to enhance the chemotherapeutic effect of curcumin against glioblastoma multiforme.

  20. Pharmacological management of acute kidney injury and chronic kidney disease in neonates.

    PubMed

    Jetton, Jennifer G; Sorenson, Mark

    2017-04-01

    Both acute kidney injury (AKI) and chronic kidney disease (CKD) are seen more frequently in the neonatal intensive care unit (NICU) as advances in supportive care improve the survival of critically ill infants as well as those with severe, congenital kidney and urinary tract anomalies. Many aspects of the infant's care, including fluid balance, electrolyte and mineral homeostasis, acid-base balance, and growth and nutrition require close monitoring by and collaboration among neonatologists, nephrologists, dieticians, and pharmacologists. This educational review summarizes the therapies widely used for neonates with AKI and CKD. Use of these therapies is extrapolated from data in older children and adults or based on clinical experience and case series. There is a critical need for more research on the use of therapies in infants with kidney disease as well as for the development of drug delivery systems and preparations scaled more appropriately for these small patients.

  1. Pharmacology of nicotinic receptor-mediated inhibition in rat dorsolateral septal neurones.

    PubMed Central

    Wong, L A; Gallagher, J P

    1991-01-01

    1. Intracellular electrophysiological techniques were employed to investigate the effects of nicotinic receptor stimulation on rat dorsolateral septal nucleus (DLSN) neurones in a submerged rat brain slice preparation. 2. Acetylcholine (in the presence of the muscarinic antagonist, atropine), nicotine or dimethylphenylpiperazinium (DMPP), applied either by pressure ejection or superfusion, produced predominantly a membrane potential hyperpolarization. 3. Following concentration-response comparisons, DMPP appeared to exhibit fewer desensitizing properties and greater efficacy than nicotine with half-maximal hyperpolarizing responses attainable at 3 and 10 microM, respectively. 4. Pharmacological analyses revealed that the agonist-induced membrane hyperpolarization was sensitive to antagonism by mecamylamine (50-100 microM) and neuronal bungarotoxin (0.2-0.3 microM), but not alpha-bungarotoxin (0.5-1.0 microM), curare (10-50 microM) or dihydro-beta-erythroidine (50-100 microM). 5. Hyperpolarizing responses to DMPP were found to reverse near the equilibrium potential for potassium and were sensitive to changes in extracellular potassium concentration as predicted by the Nernst equation. Under single-electrode voltage clamp, application of DMPP produced an outward current (75-100 pA) which approached reversal at around -88 mV. These findings indicated that the hyperpolarizing response to nicotinic receptor stimulation was mediated by changes in membrane permeability to potassium. 6. DMPP-induced membrane hyperpolarization resulted from a direct action on postsynaptic DLSN neurones since the response persisted under conditions of superfusion with calcium-free/high-magnesium media or tetrodotoxin; both conditions blocked orthodromically induced neurotransmission. The hyperpolarizing response remained unaltered in TTX but was diminished in calcium-free/high-magnesium media. Further studies revealed blockade of the DMPP response following intracellular injection of EGTA

  2. A novel pharmacological strategy by PTEN inhibition for improving metabolic resuscitation and survival after mouse cardiac arrest.

    PubMed

    Li, Jing; Wang, Huashan; Zhong, Qiang; Zhu, Xiangdong; Chen, Sy-Jou; Qian, Yuanyu; Costakis, Jim; Bunney, Gabrielle; Beiser, David G; Leff, Alan R; Lewandowski, E Douglas; ÓDonnell, J Michael; Vanden Hoek, Terry L

    2015-06-01

    Sudden cardiac arrest (SCA) is a leading cause of death in the United States. Despite return of spontaneous circulation, patients die due to post-SCA syndrome that includes myocardial dysfunction, brain injury, impaired metabolism, and inflammation. No medications improve SCA survival. Our prior work suggests that optimal Akt activation is critical for cooling protection and SCA recovery. Here, we investigate a small inhibitor of PTEN, an Akt-related phosphatase present in heart and brain, as a potential therapy in improving cardiac and neurological recovery after SCA. Anesthetized adult female wild-type C57BL/6 mice were randomized to pretreatment of VO-OHpic (VO) 30 min before SCA or vehicle control. Mice underwent 8 min of KCl-induced asystolic arrest followed by CPR. Resuscitated animals were hemodynamically monitored for 2 h and observed for 72 h. Outcomes included heart pressure-volume loops, energetics (phosphocreatine and ATP from (31)P NMR), protein phosphorylation of Akt, GSK3β, pyruvate dehydrogenase (PDH) and phospholamban, circulating inflammatory cytokines, plasma lactate, and glucose as measures of systemic metabolic recovery. VO reduced deterioration of left ventricular maximum pressure, maximum rate of change in the left ventricular pressure, and Petco2 and improved 72 h neurological intact survival (50% vs. 10%; P < 0.05). It reduced plasma lactate, glucose, IL-1β, and Pre-B cell colony enhancing factor, while increasing IL-10. VO increased phosphorylation of Akt and GSK3β in both heart and brain, and cardiac phospholamban phosphorylation while reducing p-PDH. Moreover, VO improved cardiac bioenergetic recovery. We concluded that pharmacologic PTEN inhibition enhances Akt activation, improving metabolic, cardiovascular, and neurologic recovery with increased survival after SCA. PTEN inhibitors may be a novel pharmacologic strategy for treating SCA.

  3. Pharmacologic inhibition of the renal outer medullary potassium channel causes diuresis and natriuresis in the absence of kaliuresis.

    PubMed

    Garcia, Maria L; Priest, Birgit T; Alonso-Galicia, Magdalena; Zhou, Xiaoyan; Felix, John P; Brochu, Richard M; Bailey, Timothy; Thomas-Fowlkes, Brande; Liu, Jessica; Swensen, Andrew; Pai, Lee-Yuh; Xiao, Jianying; Hernandez, Melba; Hoagland, Kimberly; Owens, Karen; Tang, Haifeng; de Jesus, Reynalda K; Roy, Sophie; Kaczorowski, Gregory J; Pasternak, Alexander

    2014-01-01

    The renal outer medullary potassium (ROMK) channel, which is located at the apical membrane of epithelial cells lining the thick ascending loop of Henle and cortical collecting duct, plays an important role in kidney physiology by regulating salt reabsorption. Loss-of-function mutations in the human ROMK channel are associated with antenatal type II Bartter's syndrome, an autosomal recessive life-threatening salt-wasting disorder with mild hypokalemia. Similar observations have been reported from studies with ROMK knockout mice and rats. It is noteworthy that heterozygous carriers of Kir1.1 mutations associated with antenatal Bartter's syndrome have reduced blood pressure and a decreased risk of developing hypertension by age 60. Although selective ROMK inhibitors would be expected to represent a new class of diuretics, this hypothesis has not been pharmacologically tested. Compound A [5-(2-(4-(2-(4-(1H-tetrazol-1-yl)phenyl)acetyl)piperazin-1-yl)ethyl)isobenzofuran-1(3H)-one)], a potent ROMK inhibitor with appropriate selectivity and characteristics for in vivo testing, has been identified. Compound A accesses the channel through the cytoplasmic side and binds to residues lining the pore within the transmembrane region below the selectivity filter. In normotensive rats and dogs, short-term oral administration of compound A caused concentration-dependent diuresis and natriuresis that were comparable to hydrochlorothiazide. Unlike hydrochlorothiazide, however, compound A did not cause any significant urinary potassium losses or changes in plasma electrolyte levels. These data indicate that pharmacologic inhibition of ROMK has the potential for affording diuretic/natriuretic efficacy similar to that of clinically used diuretics but without the dose-limiting hypokalemia associated with the use of loop and thiazide-like diuretics.

  4. Pharmacological targeting of VEGFR signaling with axitinib inhibits Tsc2-null lesion growth in the mouse model of lymphangioleiomyomatosis.

    PubMed

    Atochina-Vasserman, Elena N; Abramova, Elena; James, Melane L; Rue, Ryan; Liu, Amy Y; Ersumo, Nathan Tessema; Guo, Chang-Jiang; Gow, Andrew J; Krymskaya, Vera P

    2015-12-15

    Pulmonary lymphangioleiomyomatosis (LAM), a rare progressive lung disease associated with mutations of the tuberous sclerosis complex 2 (Tsc2) tumor suppressor gene, manifests by neoplastic growth of LAM cells, induction of cystic lung destruction, and respiratory failure. LAM severity correlates with upregulation in serum of the prolymphangiogenic vascular endothelial growth factor D (VEGF-D) that distinguishes LAM from other cystic diseases. The goals of our study was to determine whether Tsc2 deficiency upregulates VEGF-D, and whether axitinib, the Food and Drug Administration-approved small-molecule inhibitor of VEGF receptor (VEGFR) signaling, will reduce Tsc2-null lung lesion growth in a mouse model of LAM. Our data demonstrate upregulation of VEGF-D in the serum and lung lining in mice with Tsc2-null lesions. Progressive growth of Tsc2-null lesions induces recruitment and activation of inflammatory cells and increased nitric oxide production. Recruited cells isolated from the lung lining of mice with Tsc2-null lesions demonstrate upregulated expression of provasculogenic Vegfa, prolymphangiogenic Figf, and proinflammatory Nos2, Il6, and Ccl2 genes. Importantly, axitinib is an effective inhibitor of Tsc2-null lesion growth and inflammatory cell recruitment, which correlates with reduced VEGF-D levels in serum and lung lining. Our data demonstrate that pharmacological inhibition of VEGFR signaling with axitinib inhibits Tsc2-null lesion growth, attenuates recruitment and activation of inflammatory cells, and reduces VEGF-D levels systemically and in the lung lining. Our study suggests a potential therapeutic benefit of inhibition of VEGFR signaling for treatment of LAM.

  5. Pharmacological targeting of CSF1R inhibits microglial proliferation and prevents the progression of Alzheimer’s-like pathology

    PubMed Central

    Olmos-Alonso, Adrian; Schetters, Sjoerd T. T.; Sri, Sarmi; Askew, Katharine; Mancuso, Renzo; Vargas-Caballero, Mariana; Holscher, Christian; Perry, V. Hugh

    2016-01-01

    The proliferation and activation of microglial cells is a hallmark of several neurodegenerative conditions. This mechanism is regulated by the activation of the colony-stimulating factor 1 receptor (CSF1R), thus providing a target that may prevent the progression of conditions such as Alzheimer’s disease. However, the study of microglial proliferation in Alzheimer’s disease and validation of the efficacy of CSF1R-inhibiting strategies have not yet been reported. In this study we found increased proliferation of microglial cells in human Alzheimer’s disease, in line with an increased upregulation of the CSF1R-dependent pro-mitogenic cascade, correlating with disease severity. Using a transgenic model of Alzheimer’s-like pathology (APPswe, PSEN1dE9; APP/PS1 mice) we define a CSF1R-dependent progressive increase in microglial proliferation, in the proximity of amyloid-β plaques. Prolonged inhibition of CSF1R in APP/PS1 mice by an orally available tyrosine kinase inhibitor (GW2580) resulted in the blockade of microglial proliferation and the shifting of the microglial inflammatory profile to an anti-inflammatory phenotype. Pharmacological targeting of CSF1R in APP/PS1 mice resulted in an improved performance in memory and behavioural tasks and a prevention of synaptic degeneration, although these changes were not correlated with a change in the number of amyloid-β plaques. Our results provide the first proof of the efficacy of CSF1R inhibition in models of Alzheimer’s disease, and validate the application of a therapeutic strategy aimed at modifying CSF1R activation as a promising approach to tackle microglial activation and the progression of Alzheimer’s disease. PMID:26747862

  6. Chronic pharmacologic inhibition of EGFR leads to cardiac dysfunction in C57BL/6J mice

    SciTech Connect

    Barrick, Cordelia J.; Yu Ming; Chao, H.-H.; Threadgill, David W.

    2008-05-01

    Molecule-targeted therapies like those against the epidermal growth factor receptor (EGFR) are becoming widely used in the oncology clinic. With improvements in treatment efficacy, many cancers are being treated as chronic diseases, with patients having prolonged exposure to several therapies that were previously only given acutely. The consequence of chronic suppression of EGFR activity may lead to unexpected toxicities like altered cardiac physiology, a common organ site for adverse drug effects. To explore this possibility, we treated C57BL/6J (B6) mice with two EGFR small molecule tyrosine kinase inhibitors (TKIs), irreversible EKB-569 and reversible AG-1478, orally for 3 months. In B6 female mice, chronic exposure to both TKIs depressed body weight gain and caused significant changes in left ventricular (LV) wall thickness and cardiac function. No significant differences were observed in heart weight or cardiomyocyte size but histological analysis revealed an increase in fibrosis and in the numbers of TUNEL-positive cells in the hearts from treated female mice. Consistent with histological results, LV apoptotic gene expression was altered, with significant downregulation of the anti-apoptotic gene Bcl2l1. Although there were no significant differences in any of these endpoints in treated male mice, suggesting sex may influence susceptibility to TKI mediated toxicity, the LVs of treated male mice had significant upregulation of Egf, Erbb2 and Nppb over controls. Taken together, these data suggest that chronic dietary exposure to TKIs may result in pathological and physiological changes in the heart.

  7. Inhibition of pancreatic oxidative damage by stilbene derivative dihydro-resveratrol: implication for treatment of acute pancreatitis

    PubMed Central

    Tsang, Siu Wai; Guan, Yi-Fu; Wang, Juan; Bian, Zhao-Xiang; Zhang, Hong-Jie

    2016-01-01

    Trans-resveratrol is a natural stilbenoid possessing multifarious pharmacological benefits; however, when orally consumed, it is rapidly metabolised by colonic microflora and converted to dihydro-resveratrol. Thus, this microbial metabolite is of great therapeutic relevance. In the present study, upon the oral administration of dihydro-resveratrol (10–50 mg/kg), the severity of acute pancreatitis in the cerulein-treated rats was significantly ameliorated as evidenced by decreased α-amylase activities in the plasma and lessened oedema formation in the pancreatic parenchyma. In addition, the generation of intracellular reactive oxidative products, including malondialdehyde and protein carbonyls, was accordingly reduced, so as the production of pro-inflammatory cytokines. While inhibiting the activities of NADPH oxidase and myeloperoxidase, the depletion of glutathione was considerably restored. Importantly, the attenuation of pancreatic oxidative damage by dihydro-resveratrol was associated with a down-regulation of the nuclear factor-kappaB and phosphatidylinositol 3′-kinase-serine/threonine kinase signalling pathways. Furthermore, we demonstrated that the solubility of dihydro-resveratrol was at least 5 times higher than trans-resveratrol whilst exhibiting a much lower cytotoxicity. Collectively, the current findings accentuate new mechanistic insight of dihydro-resveratrol in pancreatic oxidative damage, and advocate its therapeutic potential for the management of acute pancreatitis, particularly for patients unresponsive to trans-resveratrol due to the lack of proper microbial strains. PMID:26971398

  8. Inhibition of pancreatic oxidative damage by stilbene derivative dihydro-resveratrol: implication for treatment of acute pancreatitis.

    PubMed

    Tsang, Siu Wai; Guan, Yi-Fu; Wang, Juan; Bian, Zhao-Xiang; Zhang, Hong-Jie

    2016-03-14

    Trans-resveratrol is a natural stilbenoid possessing multifarious pharmacological benefits; however, when orally consumed, it is rapidly metabolised by colonic microflora and converted to dihydro-resveratrol. Thus, this microbial metabolite is of great therapeutic relevance. In the present study, upon the oral administration of dihydro-resveratrol (10-50 mg/kg), the severity of acute pancreatitis in the cerulein-treated rats was significantly ameliorated as evidenced by decreased α-amylase activities in the plasma and lessened oedema formation in the pancreatic parenchyma. In addition, the generation of intracellular reactive oxidative products, including malondialdehyde and protein carbonyls, was accordingly reduced, so as the production of pro-inflammatory cytokines. While inhibiting the activities of NADPH oxidase and myeloperoxidase, the depletion of glutathione was considerably restored. Importantly, the attenuation of pancreatic oxidative damage by dihydro-resveratrol was associated with a down-regulation of the nuclear factor-kappaB and phosphatidylinositol 3'-kinase-serine/threonine kinase signalling pathways. Furthermore, we demonstrated that the solubility of dihydro-resveratrol was at least 5 times higher than trans-resveratrol whilst exhibiting a much lower cytotoxicity. Collectively, the current findings accentuate new mechanistic insight of dihydro-resveratrol in pancreatic oxidative damage, and advocate its therapeutic potential for the management of acute pancreatitis, particularly for patients unresponsive to trans-resveratrol due to the lack of proper microbial strains.

  9. Characteristics of patients frequently subjected to pharmacological and mechanical restraint--a register study in three Norwegian acute psychiatric wards.

    PubMed

    Knutzen, Maria; Bjørkly, Stål; Eidhammer, Gunnar; Lorentzen, Steinar; Mjøsund, Nina Helen; Opjordsmoen, Stein; Sandvik, Leiv; Friis, Svein

    2014-01-30

    This retrospective study from three catchment-area-based acute psychiatric wards showed that of all the pharmacologically and mechanically restrained patients (n=373) 34 (9.1%) had been frequently restrained (6 or more times). These patients accounted for 39.2% of all restraint episodes during the two-year study period. Adjusted binary logistic regression analyses showed that the odds for being frequently restrained were 91% lower among patients above 50 years compared to those aged 18-29 years; a threefold increase (OR=3.1) for those admitted 3 times or more compared to patients with only one stay; and, finally, a threefold increase (OR=3.1) if the length of stay was 16 days or more compared to those admitted for 0-4 days. Among frequently restrained patients, males (n=15) had significantly longer stays than women (n=19), and 8 of the females had a diagnosis of personality disorder, compared to none among males. Our study showed that being frequently restrained was associated with long inpatient stay, many admissions and young age. Teasing out patient characteristics associated with the risk of being frequently restraint may contribute to reduce use of restraint by developing alternative interventions for these patients.

  10. Pharmacological Inhibition of polysialyltransferase ST8SiaII Modulates Tumour Cell Migration

    PubMed Central

    Al-Saraireh, Yousef M. J.; Sutherland, Mark; Springett, Bradley R.; Freiberger, Friedrich; Ribeiro Morais, Goreti; Loadman, Paul M.; Errington, Rachel J.; Smith, Paul J.; Fukuda, Minoru; Gerardy-Schahn, Rita; Patterson, Laurence H.; Shnyder, Steven D.; Falconer, Robert A.

    2013-01-01

    Polysialic acid (polySia), an α-2,8-glycosidically linked polymer of sialic acid, is a developmentally regulated post-translational modification predominantly found on NCAM (neuronal cell adhesion molecule). Whilst high levels are expressed during development, peripheral adult organs do not express polySia-NCAM. However, tumours of neural crest-origin re-express polySia-NCAM: its occurrence correlates with aggressive and invasive disease and poor clinical prognosis in different cancer types, notably including small cell lung cancer (SCLC), pancreatic cancer and neuroblastoma. In neuronal development, polySia-NCAM biosynthesis is catalysed by two polysialyltransferases, ST8SiaII and ST8SiaIV, but it is ST8SiaII that is the prominent enzyme in tumours. The aim of this study was to determine the effect of ST8SiaII inhibition by a small molecule on tumour cell migration, utilising cytidine monophosphate (CMP) as a tool compound. Using immunoblotting we showed that CMP reduced ST8iaII-mediated polysialylation of NCAM. Utilizing a novel HPLC-based assay to quantify polysialylation of a fluorescent acceptor (DMB-DP3), we demonstrated that CMP is a competitive inhibitor of ST8SiaII (Ki = 10 µM). Importantly, we have shown that CMP causes a concentration-dependent reduction in tumour cell-surface polySia expression, with an absence of toxicity. When ST8SiaII-expressing tumour cells (SH-SY5Y and C6-STX) were evaluated in 2D cell migration assays, ST8SiaII inhibition led to significant reductions in migration, while CMP had no effect on cells not expressing ST8SiaII (DLD-1 and C6-WT). The study demonstrates for the first time that a polysialyltransferase inhibitor can modulate migration in ST8SiaII-expressing tumour cells. We conclude that ST8SiaII can be considered a druggable target with the potential for interfering with a critical mechanism in tumour cell dissemination in metastatic cancers. PMID:23951351

  11. Pharmacological investigations of Punica granatum in glycerol-induced acute renal failure in rats

    PubMed Central

    Singh, Amrit Pal; Singh, Amteshwar Jaggi; Singh, Nirmal

    2011-01-01

    Objective: The present study was designed to investigate the ameliorative potential and possible mechanism of hydroalcoholic extract of flowers of P. granatum in glycerol-induced acute renal failure (ARF) in rats. Materials and Methods: The rats were subjected to rhabdomyolytic ARF by single intramuscular injection of hypertonic glycerol (50% v/v; 8 ml/kg) and the animals were sacrificed after 24 hours of glycerol injection. The plasma creatinine, blood urea nitrogen, creatinine clearance, and histopathological studies were performed to assess the degree of renal injury. Results: Pretreatment with hydroalcoholic extract of flowers of P. granatum (125 and 250 mg/kg p.o. twice daily for 3 days) significantly attenuated hypertonic glycerol-induced renal dysfunction in a dose-dependent manner. BADGE (Bisphenol-A-diglycidyl ether) (30 mg/kg), a peroxisome proliferator-activated receptor (PPAR)-γ antagonist, and N(omega)-nitro-l-arginine-methyl ester (L-NAME) (10, 20, and 40 mg/kg), nitric oxide synthase inhibitor, were employed to explore the mechanism of renoprotective effects of Punica granatum. Administration of BADGE (30 mg/kg) and L-NAME (40 mg/kg) abolished the beneficial effects of P. granatum in glycerol-induced renal dysfunction. Conclusion: Hydroalcoholic extract of flowers of P. granatum has ameliorative potential in attenuating myoglobinuric renal failure and its renoprotective effects involve activation of PPAR-γ and nitric oxide-dependent signaling pathway. PMID:22021999

  12. Behavioral and pharmacological validation of an integrated fear-potentiated startle and prepulse inhibition paradigm.

    PubMed

    Zhang, Mengjiao; Li, Ming

    2016-07-01

    Fear-potentiated startle (FPS) and prepulse inhibition (PPI) of acoustic startle are two widely used paradigms specifically designed to capture the impact of negative emotion (e.g. fear) and preattentive function on startle response. Currently, there is no single paradigm that incorporates both FPS and PPI, making it impossible to examine the potential interactions between fear and attention in the regulation of startle response. In this study, we developed an integrated FPS and PPI test protocol and validated it with psychoactive drugs. In Experiment 1, male Sprague-Dawley rats were randomly assigned to one of five groups, receiving either Light -Shock conditioning trials, non-overlapping Lights and Shocks, Light alone, Shock alone, or no Light and Shock. They were then tested for startle response and PPI concurrently, under the Light or No Light. FPS was observed only in rats subjected to fear conditioning, whereas all rats showed PPI and startle habituation. Experiment 2 used this paradigm and demonstrated a dissociative effect between diazepam (an anxiolytic drug) and phencyclidine (a nonselective NMDA receptor antagonist) on FPS and PPI. Diazepam suppressed both FPS and PPI, while PCP selectively disrupted PPI but not FPS. The diazepam's anxiolytic effect on FPS was further confirmed in the elevated plus maze test. Together, our findings indicate that our paradigm combines FPS and PPI into a single paradigm, and that is useful to examine potential interactions between multiple psychological processes, to identify the common neural substrates and to screen new drugs with multiple psychoactive effects.

  13. Direct pharmacological inhibition of β-catenin by RNA interference in tumors of diverse origin

    PubMed Central

    Ganesh, Shanthi; Koser, Martin; Cyr, Wendy; Chopda, Girish; Tao, Junyan; Shui, Xue; Ying, Bo; Chen, Dongyu; Pandya, Purva; Chipumuro, Edmond; Siddiquee, Zakir; Craig, Kevin; Lai, Chengjung; Dudek, Henryk; Monga, Satdarshan; Wang, Weimin; Brown, Bob D.; Abrams, Marc

    2016-01-01

    The Wnt/β-catenin pathway is among the most frequently altered signaling networks in human cancers. Despite decades of preclinical and clinical research, efficient therapeutic targeting of Wnt/β-catenin has been elusive. RNA interference (RNAi) technology silences genes at the mRNA level, and therefore can be applied to previously-undruggable targets. Lipid nanoparticles (LNPs) represent an elegant solution for delivery of RNAi-triggering oligonucleotides to disease-relevant tissues, but have been mostly restricted to applications in the liver. In this study, we systematically tuned the composition of a prototype LNP to enable tumor-selective delivery of a Dicer-substrate siRNA (DsiRNA) targeting CTNNB1, the gene encoding β-catenin. This formulation, termed EnCore-R, demonstrated pharmacodynamic activity in subcutaneous human tumor xenografts, orthotopic patient-derived xenograft (PDx) tumors, disseminated hematopoietic tumors, genetically induced primary liver tumors, metastatic colorectal tumors, murine metastatic melanoma. DsiRNA delivery was homogeneous in tumor sections, selective over normal liver and independent of apolipoprotein-E binding. Significant tumor growth inhibition was achieved in Wnt-dependent colorectal and hepatocellular carcinoma models, but not in Wnt-independent tumors. Finally, no evidence of accelerated blood clearance or sustained liver transaminase elevation was observed after repeated dosing in nonhuman primates. These data support further investigation to gain mechanistic insight, optimize dose regimens and identify efficacious combinations with standard-of-care therapeutics. PMID:27390343

  14. Structural Basis for Feedback and Pharmacological Inhibition of Saccharomyces cerevisiae Glutamate Cysteine Ligase

    SciTech Connect

    Biterova, Ekaterina I.; Barycki, Joseph J.

    2010-04-30

    Structural characterization of glutamate cysteine ligase (GCL), the enzyme that catalyzes the initial, rate-limiting step in glutathione biosynthesis, has revealed many of the molecular details of substrate recognition. To further delineate the mechanistic details of this critical enzyme, we have determined the structures of two inhibited forms of Saccharomyces cerevisiae GCL (ScGCL), which shares significant sequence identity with the human enzyme. In vivo, GCL activity is feedback regulated by glutathione. Examination of the structure of ScGCL-glutathione complex (2.5 A; R = 19.9%, R(free) = 25.1%) indicates that the inhibitor occupies both the glutamate- and the presumed cysteine-binding site and disrupts the previously observed Mg(2+) coordination in the ATP-binding site. l-Buthionine-S-sulfoximine (BSO) is a mechanism-based inhibitor of GCL and has been used extensively to deplete glutathione in cell culture and in vivo model systems. Inspection of the ScGCL-BSO structure (2.2 A; R = 18.1%, R(free) = 23.9%) confirms that BSO is phosphorylated on the sulfoximine nitrogen to generate the inhibitory species and reveals contacts that likely contribute to transition state stabilization. Overall, these structures advance our understanding of the molecular regulation of this critical enzyme and provide additional details of the catalytic mechanism of the enzyme.

  15. Neprilysin inhibition: A brief review of past pharmacological strategies for heart failure treatment and future directions.

    PubMed

    Howell, Erik H; Cameron, Scott J

    2016-01-01

    Heart failure (HF) is a manifestation of aberrant vascular responses and remains a public health concern with a worldwide prevalence of around 23 million and a 5-year mortality numerically equivalent to many cancers. Over the last two decades, mortality from HF reached a plateau with current pharmaceutical agents and mechanical cardiac support. In the last several years, various "novel" pharmaceutical agents have been tested in clinical trials and ultimately met with disappointment, showing only incremental benefit in the treatment of HF. Designing a HF drug with enhanced efficacy over existing agents seemed like a Sisyphean task. Yet again, pharmaceutical chemists have demonstrated their prowess in lateral thinking by developing a vasoactive agent which is a co-crystallized compound of valsartan and sacubitril in a one-to-one molar ratio; the former molecule belongs to a family of agents that are the current standard of care for HF and the latter molecule is a novel agent which inhibits neprilysin - a neutral endopeptidase found in human plasma which alters neurohumoral responses. In July of 2015, a drug which is a combination of valsartan and sacubitril was formally licensed by the United States Food and Drug Administration for the treatment of HF. This review describes the evolution of HF medications focusing on rational drug design with the first HF medication, the beta-adrenergic receptor antagonist. We then discuss the biochemical and physiological properties of sacubitril/valsartan which likely lead to its dramatic ability to ameliorate HF mortality.

  16. Neprilysin inhibition: a brief review of past pharmacological strategies for heart failure treatment and future directions

    PubMed Central

    Howell, Erik H.; Cameron, Scott J.

    2016-01-01

    Heart failure (HF) is a manifestation of aberrant vascular responses and remains a public health concern with a worldwide prevalence of around 23 million and a 5-year mortality numerically equivalent to many cancers. Over the last two decades, mortality from HF reached a plateau with current pharmaceutical agents and mechanical cardiac support. In the last several years, various “novel” pharmaceutical agents have been tested in clinical trials and ultimately met with disappointment, showing only incremental benefit in the treatment of HF. Designing a HF drug with enhanced efficacy over existing agents seemed like a Sisyphean task. Yet again, pharmaceutical chemists have demonstrated their prowess in lateral thinking by developing a vasoactive agent which is a co-crystallized compound of valsartan and sacubitril in a one-to-one molar ratio; the former molecule belongs to a family of agents that are the current standard of care for HF and the latter molecule is a novel agent which inhibits neprilysin — a neutral endopeptidase found in human plasma which alters neurohumoral responses. In July of 2015, a drug which is a combination of valsartan and sacubitril was formally licensed by the United States Food and Drug Administration for the treatment of HF. This review describes the evolution of HF medications focusing on rational drug design with the first HF medication, the beta adrenergic receptor antagonist. We then discuss the biochemical and physiological properties of sacubitril/valsartan which likely lead to its dramatic ability to ameliorate HF mortality. PMID:27665860

  17. Genetic and Pharmacological Inhibition of p38α Improves Locomotor Recovery after Spinal Cord Injury

    PubMed Central

    Umezawa, Hiroki; Naito, Yusuke; Tanaka, Kensuke; Yoshioka, Kento; Suzuki, Kenichi; Sudo, Tatsuhiko; Hagihara, Masahiko; Hatano, Masahiko; Tatsumi, Koichiro; Kasuya, Yoshitoshi

    2017-01-01

    One of the mitogen-activated protein kinases, p38α plays a crucial role in various inflammatory diseases and apoptosis of various types of cells. In this study, we investigated the pathophysiological roles of p38α in spinal cord injury (SCI), using a mouse model. Lateral hemisection at T9 of the SC was performed in wild type (WT) and p38α+/- mice (p38α-/- showed embryonic lethality). p38α+/- mice showed a better functional recovery from SCI-associated paralyzed hindlimbs compared to WT mice at 7 days post-injury (dpi), which remained until 28 dpi (an end time point of monitoring the behavior). In histopathological analysis at 28 dpi, there was more axonal regeneration with remyelination on the caudal side of the lesion epicenter in p38α+/- mice than in WT mice. At 7 dpi, infiltration of inflammatory cells into the lesion and expression of cytokines in the lesion were reduced in p38α+/- mice compared with WT mice. At the same time point, the number of apoptotic oligodendrocytes in the white matter at the caudal boarder of the lesion of p38α+/- mice was lower than that of WT mice. At 14 dpi, more neural and oligodendrocyte precursor cells in the gray matter and white matter, respectively, were observed around the lesion epicenter of p38α+/- mice compared with the case of WT mice. At the same time point, astrocytic scar formation was less apparent in p38α+/- than in WT mice, while compaction of inflammatory immune cells associated with the wound contraction was more apparent in p38α+/- than in WT mice. Furthermore, we verified the effectiveness of oral administration of SB239063, a p38α inhibitor on the hindlimb locomotor recovery after SCI. These results suggest that p38α deeply contributes to the pathogenesis of SCI and that inhibition of p38α is a beneficial strategy to recovery from SCI. PMID:28261102

  18. Pharmacological inhibition of mannose-binding lectin ameliorates neurobehavioral dysfunction following experimental traumatic brain injury.

    PubMed

    De Blasio, Daiana; Fumagalli, Stefano; Longhi, Luca; Orsini, Franca; Palmioli, Alessandro; Stravalaci, Matteo; Vegliante, Gloria; Zanier, Elisa R; Bernardi, Anna; Gobbi, Marco; De Simoni, Maria-Grazia

    2017-03-01

    Mannose-binding lectin is present in the contusion area of traumatic brain-injured patients and in that of traumatic brain-injured mice, where mannose-binding lectin-C exceeds mannose-binding lectin-A. The reduced susceptibility to traumatic brain injury of mannose-binding lectin double knock-out mice (mannose-binding lectin(-/-)) when compared to wild type mice suggests that mannose-binding lectin may be a therapeutic target following traumatic brain injury. Here, we evaluated the effects of a multivalent glycomimetic mannose-binding lectin ligand, Polyman9, following traumatic brain injury in mice. In vitro surface plasmon resonance assay indicated that Polyman9 dose-dependently inhibits the binding to immobilized mannose residues of plasma mannose-binding lectin-C selectively over that of mannose-binding lectin-A. Male C57Bl/6 mice underwent sham/controlled cortical impact traumatic brain injury and intravenous treatment with Polyman9/saline. Ex-vivo surface plasmon resonance studies confirmed that Polyman9 effectively reduces the binding of plasma mannose-binding lectin-C to immobilized mannose residues. In vivo studies up to four weeks post injury, showed that Polyman9 induces significant improvement in sensorimotor deficits (by neuroscore and beam walk), promotes neurogenesis (73% increase in doublecortin immunoreactivity), and astrogliosis (28% increase in glial fibrillary acid protein). Polyman9 administration in brain-injured mannose-binding lectin(-/-) mice had no effect on post-traumatic brain-injured functional deficits, suggestive of the specificity of its neuroprotective effects. The neurobehavioral efficacy of Polyman9 implicates mannose-binding lectin-C as a novel therapeutic target for traumatic brain injury.

  19. Inhibition of p38 MAPK Phosphorylation Is Critical for Bestatin to Enhance ATRA-Induced Cell Differentiation in Acute Promyelocytic Leukemia NB4 Cells.

    PubMed

    Qian, Xijun; He, Jingsong; Zhao, Yi; Lin, Maofang

    2016-01-01

    Bestatin has been known as an immunomodulating agent in anti-leukemia treatment. The mechanism by which Bestatin enhances all-trans retinoic acid (ATRA)-induced cell differentiation of acute promyelocytic leukemia (APL) cells is generally attributed to inhibition of cell surface CD13/aminopeptidase N activity. Bestatin also exerts its biological activities besides its ability to inhibit aminopeptidase N enzymatic activity. This article provides data to support an alternative mechanism regarding an important role of inhibition of p38 mitogen-activated protein kinase (MAPK) signal pathway in Bestatin's anti-leukemia effect. Bestatin enhanced ATRA-induced differentiation and inhibited ATRA-driven phosphorylation of p38 MAPK in ATRA-sensitive APL NB4 cells. In contrast, Bestatin could not reverse the differentiation block in ATRA-resistant APL MR2 cells, in which ATRA was unable to induce phosphorylation of p38 MAPK. Moreover, CD13 ligation with anti-CD13 antibody WM-15 resulted in phosphorylation of p38 MAPK, reduced the inhibition of Bestatin on the phosphorylation of p38 MAPK, and completely abolished the enhancement of Bestatin on ATRA-inducing differentiation in NB4 cells. This study shows that inhibition of p38 MAPK phosphorylation is critical for Bestatin to enhance ATRA-induced cell differentiation in ATRA-sensitive APL NB4 cells. Results suggested that pharmacological inhibition of the p38 MAPK pathway might enhance ATRA-dependent differentiation.

  20. Inhibition of caspase-9 aggravates acute liver injury through suppression of cytoprotective autophagy

    PubMed Central

    Guo, Rui; Lin, Bin; Pan, Jing Fei; Liong, Emily C.; Xu, Ai Min; Youdim, Moussa; Fung, Man Lung; So, Kwok Fai; Tipoe, George L.

    2016-01-01

    Acute liver disease is characterized by inflammation, oxidative stress and necrosis, which can greatly influence the long term clinical outcome and lead to liver failure or cancer. Here, we initially demonstrated the beneficial role of caspase-9-dependent autophagy in acute liver injury. Treatment with caspase-9 inhibitor z-LEHD-FMK in HepG2 cells, AML12 cells and C57BL/b6N mice exacerbated CCl4-induced acute hepatocellular damage, and also down-regulated autophagy markers expression levels, indicating that caspase-9 inhibition may aggravate acute liver damage by suppressing cytoprotective autophagy. CCl4 was used as an acute liver injury inducer which caused oxidative stress and apoptosis through up-regulation of HIF-1α, as well as triggered hepatic inflammation and necroptosis via TLR4/NF-κB pathway. Caspase-9 Thr125 site was firstly phosphorylated by ERK1/2 which subsequently activated the cytoprotective autophagy process to attenuate acute CCl4 injury. Caspase-9 inhibition further aggravated hepatic necroptosis through NF-κB expression, leading to increased pro-inflammatory mediators levels, suggesting a protective role of caspase-9-dependent autophagy in the inflammatory process as well as its possibility being a new therapeutic target for the treatment of acute liver injury. PMID:27580936

  1. Inhibition of caspase-9 aggravates acute liver injury through suppression of cytoprotective autophagy.

    PubMed

    Guo, Rui; Lin, Bin; Pan, Jing Fei; Liong, Emily C; Xu, Ai Min; Youdim, Moussa; Fung, Man Lung; So, Kwok Fai; Tipoe, George L

    2016-09-01

    Acute liver disease is characterized by inflammation, oxidative stress and necrosis, which can greatly influence the long term clinical outcome and lead to liver failure or cancer. Here, we initially demonstrated the beneficial role of caspase-9-dependent autophagy in acute liver injury. Treatment with caspase-9 inhibitor z-LEHD-FMK in HepG2 cells, AML12 cells and C57BL/b6N mice exacerbated CCl4-induced acute hepatocellular damage, and also down-regulated autophagy markers expression levels, indicating that caspase-9 inhibition may aggravate acute liver damage by suppressing cytoprotective autophagy. CCl4 was used as an acute liver injury inducer which caused oxidative stress and apoptosis through up-regulation of HIF-1α, as well as triggered hepatic inflammation and necroptosis via TLR4/NF-κB pathway. Caspase-9 Thr125 site was firstly phosphorylated by ERK1/2 which subsequently activated the cytoprotective autophagy process to attenuate acute CCl4 injury. Caspase-9 inhibition further aggravated hepatic necroptosis through NF-κB expression, leading to increased pro-inflammatory mediators levels, suggesting a protective role of caspase-9-dependent autophagy in the inflammatory process as well as its possibility being a new therapeutic target for the treatment of acute liver injury.

  2. Rescue from acute neuroinflammation by pharmacological chemokine-mediated deviation of leukocytes

    PubMed Central

    2012-01-01

    observed at the COAM injection site. Conclusions These results demonstrate novel actions of COAM as an anti-inflammatory agent with beneficial effects on EAE through cell deviation. Sequestration of leukocytes in the non-CNS periphery or draining of leukocytes out of the CNS with the use of the chemokine system may thus complement existing treatment options for acute and chronic neuroinflammatory diseases. PMID:23095573

  3. Pharmacological inhibition of epsilon-protein kinase C attenuates cardiac fibrosis and dysfunction in hypertension-induced heart failure.

    PubMed

    Inagaki, Koichi; Koyanagi, Tomoyoshi; Berry, Natalia C; Sun, Lihan; Mochly-Rosen, Daria

    2008-06-01

    Studies on genetically manipulated mice suggest a role for epsilon-protein kinase C (epsilonPKC) in cardiac hypertrophy and in heart failure. The potential clinical relevance of these findings was tested here using a pharmacological inhibitor of epsilonPKC activity during the progression to heart failure in hypertensive Dahl rats. Dahl rats, fed an 8% high-salt diet from the age of 6 weeks, exhibited compensatory cardiac hypertrophy by 11 weeks, followed by heart failure at approximately 17 weeks and death by the age of approximately 20 weeks (123+/-3 days). Sustained treatment between weeks 11 and 17 with the selective epsilonPKC inhibitor epsilonV1-2 or with an angiotensin II receptor blocker olmesartan prolonged animal survival by approximately 5 weeks (epsilonV1-2: 154+/-7 days; olmesartan: 149+/-5 days). These treatments resulted in improved fractional shortening (epsilonV1-2: 58+/-2%; olmesartan: 53+/-2%; saline: 41+/-6%) and decreased cardiac parenchymal fibrosis when measured at 17 weeks without lowering blood pressure at any time during the treatment. Combined treatment with epsilonV1-2, together with olmesartan, prolonged animal survival by 5 weeks (37 days) relative to olmesartan alone (from 160+/-5 to 197+/-14 days, respectively) and by approximately 11 weeks (74 days) on average relative to saline-treated animals, suggesting that the pathway inhibited by epsilonPKC inhibition is not identical to the olmesartan-induced effect. These data suggest that an epsilonPKC-selective inhibitor such as epsilonV1-2 may have a potential in augmenting current therapeutic strategies for the treatment of heart failure in humans.

  4. Pharmacological Inhibition of NLRP3 Inflammasome Attenuates Myocardial Ischemia/Reperfusion Injury by Activation of RISK and Mitochondrial Pathways

    PubMed Central

    Tullio, Francesca; Femminò, Saveria; Nigro, Debora; Chiazza, Fausto; Collotta, Debora; Cocco, Mattia; Bertinaria, Massimo; Aragno, Manuela

    2016-01-01

    Although the nucleotide-binding oligomerization domain- (NOD-) like receptor pyrin domain containing 3 (NLRP3) inflammasome has been recently detected in the heart, its role in cardiac ischemia/reperfusion (IR) is still controversial. Here, we investigate whether a pharmacological modulation of NLRP3 inflammasome exerted protective effects in an ex vivo model of IR injury. Isolated hearts from male Wistar rats (5-6 months old) underwent ischemia (30 min) followed by reperfusion (20 or 60 min) with and without pretreatment with the recently synthetized NLRP3 inflammasome inhibitor INF4E (50 μM, 20 min before ischemia). INF4E exerted protection against myocardial IR, shown by a significant reduction in infarct size and lactate dehydrogenase release and improvement in postischemic left ventricular pressure. The formation of the NLRP3 inflammasome complex was induced by myocardial IR and attenuated by INF4E in a time-dependent way. Interestingly, the hearts of the INF4E-pretreated animals displayed a marked improvement of the protective RISK pathway and this effect was associated increase in expression of markers of mitochondrial oxidative phosphorylation. Our results demonstrate for the first time that INF4E protected against the IR-induced myocardial injury and dysfunction, by a mechanism that involves inhibition of the NLRP3 inflammasome, resulting in the activation of the prosurvival RISK pathway and improvement in mitochondrial function. PMID:28053692

  5. Pharmacologically antagonizing the CXCR4-CXCL12 chemokine pathway with AMD3100 inhibits sunlight-induced skin cancer.

    PubMed

    Sarchio, Seri N E; Scolyer, Richard A; Beaugie, Clare; McDonald, David; Marsh-Wakefield, Felix; Halliday, Gary M; Byrne, Scott N

    2014-04-01

    One way sunlight causes skin cancer is by suppressing anti-tumor immunity. A major mechanism involves altering mast cell migration via the C-X-C motif chemokine receptor 4-C-X-C motif chemokine ligand 12 (CXCR4-CXCL12) chemokine pathway. We have discovered that pharmacologically blocking this pathway with the CXCR4 antagonist AMD3100 prevents both UV radiation-induced immune suppression and skin cancer. The majority of control mice receiving UV-only developed histopathologically confirmed squamous cell carcinomas. In contrast, skin tumor incidence and burden was significantly lower in AMD3100-treated mice. Perhaps most striking was that AMD3100 completely prevented the outgrowth of latent tumors that occurred once UV irradiation ceased. AMD3100 protection from UV immunosuppression and skin cancer was associated with reduced mast cell infiltration into the skin, draining lymph nodes, and the tumor itself. Thus a major target of CXCR4 antagonism was the mast cell. Our results indicate that interfering with UV-induced CXCL12 by antagonizing CXCR4 significantly inhibits skin tumor development by blocking UV-induced effects on mast cells. Hence, the CXCR4-CXCL12 chemokine pathway is a novel therapeutic target in the prevention of UV-induced skin cancer.

  6. Glycosaminoglycan sulodexide inhibition of MMP-9 gelatinase secretion and activity: possible pharmacological role against collagen degradation in vascular chronic diseases.

    PubMed

    Mannello, Ferdinando; Medda, Virginia; Ligi, Daniela; Raffetto, Joseph D

    2013-05-01

    We evaluated the effects of the glycosaminoglycan sulodexide (SDX; antithrombotic/profibrinolytic drug) on the activity and release of matrix metalloproteinases (MMPs) in human blood. This was a prospective non-randomized study, analyzing by zymography and ELISA the in vitro effects of SDX on pro-enzyme, complexed, and active MMP forms in plasma and serum from 60 healthy donors, and in U-937 leukemia cell line. The levels and zymographic profile of MMP-2 did not show significant changes among samples and during SDX treatments. However, pro- and complexed forms of MMP-9 were strongly affected by SDX treatment (P<0.001), with significant decrease of MMP-9 secretion from white blood cells in a dose-dependent fashion (P<0.0001), without any displacement of MMP prodomains. The mechanism of reduced release of MMP-9 forms from leukocytes and inhibition of proteolytic activity due to SDX treatment may support the hypothesis that drugs based upon inhibitors of MMP-9 activity may provide a therapeutic tool for the underlying pathological destruction of extracellular matrix, and offering novel pharmacologic applications for chronic inflammatory vascular diseases, including varicose vein and chronic venous diseases associated with enhanced MMP activation in blood and limbs.

  7. Acute effects of cocaine and cannabis on response inhibition in humans: an ERP investigation.

    PubMed

    Spronk, Desirée B; De Bruijn, Ellen R A; van Wel, Janelle H P; Ramaekers, Johannes G; Verkes, Robbert J

    2016-11-01

    Substance abuse has often been associated with alterations in response inhibition in humans. Not much research has examined how the acute effects of drugs modify the neurophysiological correlates of response inhibition, or how these effects interact with individual variation in trait levels of impulsivity and novelty seeking. This study investigated the effects of cocaine and cannabis on behavioural and event-related potential (ERP) correlates of response inhibition in 38 healthy drug using volunteers. A double-blind placebo-controlled randomized three-way crossover design was used. All subjects completed a standard Go/NoGo task after administration of the drugs. Compared with a placebo, cocaine yielded improved accuracy, quicker reaction times and an increased prefrontal NoGo-P3 ERP. Cannabis produced opposing results; slower reaction times, impaired accuracy and a reduction in the amplitude of the prefrontal NoGo-P3. Cannabis in addition decreased the amplitude of the parietally recorded P3, while cocaine did not affect this. Neither drugs specifically affected the N2 component, suggesting that pre-motor response inhibitory processes remain unaffected. Neither trait impulsivity nor novelty seeking interacted with drug-induced effects on measures of response inhibition. We conclude that acute drug effects on response inhibition seem to be specific to the later, evaluative stages of response inhibition. The acute effects of cannabis appeared less specific to response inhibition than those of cocaine. Together, the results show that the behavioural effects on response inhibition are reflected in electrophysiological correlates. This study did not support a substantial role of vulnerability personality traits in the acute intoxication stage.

  8. Pharmacologic inhibition of RORγt regulates Th17 signature gene expression and suppresses cutaneous inflammation in vivo.

    PubMed

    Skepner, Jill; Ramesh, Radha; Trocha, Mark; Schmidt, Darby; Baloglu, Erkan; Lobera, Mercedes; Carlson, Thaddeus; Hill, Jonathan; Orband-Miller, Lisa A; Barnes, Ashley; Boudjelal, Mohamed; Sundrud, Mark; Ghosh, Shomir; Yang, Jianfei

    2014-03-15

    IL-17-producing CD4(+)Th17 cells, CD8(+)Tc17 cells, and γδ T cells play critical roles in the pathogenesis of autoimmune psoriasis. RORγt is required for the differentiation of Th17 cells and expression of IL-17. In this article, we describe a novel, potent, and selective RORγt inverse agonist (TMP778), and its inactive diastereomer (TMP776). This chemistry, for the first time to our knowledge, provides a unique and powerful set of tools to probe RORγt-dependent functions. TMP778, but not TMP776, blocked human Th17 and Tc17 cell differentiation and also acutely modulated IL-17A production and inflammatory Th17-signature gene expression (Il17a, Il17f, Il22, Il26, Ccr6, and Il23) in mature human Th17 effector/memory T cells. In addition, TMP778, but not TMP776, inhibited IL-17A production in both human and mouse γδ T cells. IL-23-induced IL-17A production was also blocked by TMP778 treatment. In vivo targeting of RORγt in mice via TMP778 administration reduced imiquimod-induced psoriasis-like cutaneous inflammation. Further, TMP778 selectively regulated Th17-signature gene expression in mononuclear cells isolated from both the blood and affected skin of psoriasis patients. In summary, to our knowledge, we are the first to demonstrate that RORγt inverse agonists: 1) inhibit Tc17 cell differentiation, as well as IL-17 production by γδ T cells and CD8(+) Tc17 cells; 2) block imiquimod-induced cutaneous inflammation; 3) inhibit Th17 signature gene expression by cells isolated from psoriatic patient samples; and 4) block IL-23-induced IL-17A expression. Thus, RORγt is a tractable drug target for the treatment of cutaneous inflammatory disorders, which may afford additional therapeutic benefit over existing modalities that target only IL-17A.

  9. Inhibition of hepatic cells pyroptosis attenuates CLP-induced acute liver injury

    PubMed Central

    Chen, Yuan-Li; Xu, Guo; Liang, Xiao; Wei, Juan; Luo, Jing; Chen, Guan-Nan; Yan, Xiao-Di; Wen, Xue-Ping; Zhong, Ming; Lv, Xin

    2016-01-01

    Pyroptosis is a programmed cell death associated with caspase-1 and accompanied by the secretion of a large number of pro-inflammatory cytokines. In the acute stage of sepsis, the release of several pro-inflammatory cytokines aggravates hepatic cell death, and acute liver injury is aggravated with the progress of the disease, resulting in acute liver failure with a very high mortality rate. The present study investigated the effect of inhibiting hepatic cell pyroptosis on the septic acute liver injury. Septic acute liver injury mice model was established by cecal ligation and puncture (CLP model). The liver tissues were assessed for inflammatory infiltration by HE, serum concentrations of ALT, AST, IL-1β, and IL-18 were examined by ELISA, hepatic cell pyroptosis was determined by flow cytometry, and expressions of caspase-1 and NLRP3 were assessed by Western blot. CLP-induced acute liver injury was distinct at 24 h post-operation, with the highest hepatic cell pyroptosis rate. The pyroptosis rate and liver injury indexes were positively correlated. Western blot showed that the expressions of pyroptosis-related proteins, caspase-1, and NLRP3, were increased. Normal mouse hepatic cells were cultured in vitro and LPS+ATP introduced to establish the cell model of septic acute liver injury. The expressions of caspase-1, NLRP3, IL-1β, and IL-18 in LPS+ATP group were significantly higher than the control group by Western blot and ELISA. The inhibitors of NLRP3 (Glyburide) and caspase-1 (AC-YVAD-CMK) alone or in combination were used to pre-treat the hepatic cells, which revealed that the pyroptosis rate was decreased and the cell damage alleviated. The in vivo assay in rats showed that post inhibitor treatment, the 10-days survival was significantly improved and the liver damage reduced. Therefore, inhibiting the hepatic cell pyroptosis could alleviate CLP-induced acute liver injury, providing a novel treatment target for septic acute liver injury. PMID:28078039

  10. Influence of acute stress on response inhibition in healthy men: An ERP study.

    PubMed

    Dierolf, Angelika Margarete; Fechtner, Julia; Böhnke, Robina; Wolf, Oliver T; Naumann, Ewald

    2017-02-07

    The current study investigated the influence of acute stress and the resulting cortisol increase on response inhibition and its underlying cortical processes, using EEG. Before and after an acute stressor or a control condition, 39 healthy men performed a go/no-go task while ERPs (N2, P3), reaction times, errors, and salivary cortisol were measured. Acute stress impaired neither accuracy nor reaction times, but differentially affected the neural correlates of response inhibition; namely, stress led to enhanced amplitudes of the N2 difference waves (N2d, no-go minus go), indicating enhanced response inhibition and conflict monitoring. Moreover, participants responding to the stressor with an acute substantial rise in cortisol (high cortisol responders) showed reduced amplitudes of the P3 of the difference waves (P3d, no-go minus go) after the stressor, indicating an impaired evaluation and finalization of the inhibitory process. Our findings indicate that stress leads to a reallocation of cognitive resources to the neural subprocesses of inhibitory control, strengthening premotor response inhibition and the detection of response conflict, while concurrently diminishing the subsequent finalization process within the stream of processing.

  11. Oral Administration of Escin Inhibits Acute Inflammation and Reduces Intestinal Mucosal Injury in Animal Models

    PubMed Central

    Li, Minmin; Lu, Chengwen; Zhang, Leiming; Zhang, Jianqiao; Du, Yuan; Duan, Sijin; Wang, Tian; Fu, Fenghua

    2015-01-01

    The present study aimed to investigate the effects of oral administration of escin on acute inflammation and intestinal mucosal injury in animal models. The effects of escin on carrageenan-induced paw edema in a rat model of acute inflammation, cecal ligation and puncture (CLP) induced intestinal mucosal injury in a mouse model, were observed. It was shown that oral administration of escin inhibits carrageenan-induced paw edema and decreases the production of prostaglandin E2 (PGE2) and cyclooxygenase- (COX-) 2. In CLP model, low dose of escin ameliorates endotoxin induced liver injury and intestinal mucosal injury and increases the expression of tight junction protein claudin-5 in mice. These findings suggest that escin effectively inhibits acute inflammation and reduces intestinal mucosal injury in animal models. PMID:26199634

  12. Acute inhibition of iron bioavailability by zinc: studies in humans.

    PubMed

    Olivares, Manuel; Pizarro, Fernando; Ruz, Manuel; de Romaña, Daniel López

    2012-08-01

    Iron (Fe) and zinc (Zn) deficiencies constitute two of the most important nutritional and public health problems affecting developing countries. Combined supplementation or fortification with Zn and Fe are strategies that can be used to improve the Zn and Fe status of a population. However, there is concern about potential negative interactions between these two micronutrients due to a competitive binding to DMT1 and Zip14 transporter. Studies performed in humans have shown an inhibitory effect of Zn on Fe absorption when both minerals are given together as a solution in fasting conditions. We found that at low doses of iron (0.5 mg) the threshold for the inhibition of iron bioavailability was at a Zn:Fe wt/wt ratio ≥5.9:1, whereas at higher doses of Fe (10 mg) this inhibition occurred at 1:1 Zn:Fe wt/wt ratio. This differential response could be explained by the variation in the abundance of both cations as they compete for a limited number of shared transporters at the enterocyte. Conflicting results have been obtained when this interaction was studied in different food matrices. A negative interaction was not observed when Fe and Zn were provided in a composite hamburger meal, premature formula, human milk, or cow milk. A decrease on Fe absorption was observed in only 1 of 3 studies when Fe and Zn were supplied in wheat flour. The possibility of a negative interaction should be considered for supplementation or fortification programs with both microminerals.

  13. Calcitonin gene-related peptide inhibits local acute inflammation and protects mice against lethal endotoxemia.

    PubMed

    Gomes, Rachel Novaes; Castro-Faria-Neto, Hugo C; Bozza, Patricia T; Soares, Milena B P; Shoemaker, Charles B; David, John R; Bozza, Marcelo T

    2005-12-01

    Calcitonin gene-related peptide (CGRP), a potent vasodilatory peptide present in central and peripheral neurons, is released at inflammatory sites and inhibits several macrophage, dendritic cell, and lymphocyte functions. In the present study, we investigated the role of CGRP in models of local and systemic acute inflammation and on macrophage activation induced by lipopolysaccharide (LPS). Intraperitoneal pretreatment with synthetic CGRP reduces in approximately 50% the number of neutrophils in the blood and into the peritoneal cavity 4 h after LPS injection. CGRP failed to inhibit neutrophil recruitment induced by the direct chemoattractant platelet-activating factor, whereas it significantly inhibited LPS-induced KC generation, suggesting that the effect of CGRP on neutrophil recruitment is indirect, acting on chemokine production by resident cells. Pretreatment of mice with 1 mug of CGRP protects against a lethal dose of LPS. The CGRP-induced protection is receptor mediated because it is completely reverted by the CGRP receptor antagonist, CGRP 8-37. The protective effect of CGRP correlates with an inhibition of TNF-alpha and an induction of IL-6 and IL-10 in mice sera 90 min after LPS challenge. Finally, CGRP significantly inhibits LPS-induced TNF-alpha released from mouse peritoneal macrophages. These results suggest that activation of the CGRP receptor on macrophages during acute inflammation could be part of the negative feedback mechanism controlling the extension of acute inflammatory responses.

  14. Pharmacological inhibition of ASBT changes bile composition and blocks progression of sclerosing cholangitis in mdr2 knockout mice

    PubMed Central

    Miethke, Alexander G; Zhang, Wujuan; Simmons, Julie; Taylor, Amy; Shi, Tiffany; Shanmukhappa, Shiva Kumar; Karns, Rebekah; White, Shana; Jegga, Anil G; Lages, Celine S; Nkinin, Stephenson; Keller, Bradley T; Setchell, Kenneth D. R.

    2015-01-01

    Deficiency for mdr2, a canalicular phospholipid floppase, leads to excretion of low phospholipid “toxic” bile causing progressive cholestasis. We hypothesize that pharmacological inhibition of the ileal apical sodium-dependent bile acid transporter (ASBT) blocks progression of sclerosing cholangitis in mdr2−/− mice. 30-day-old, female mdr2−/− mice were fed high-fat chow containing 0.006% SC-435, a minimally absorbed, potent inhibitor of ASBT, providing on average 11 mg/kg/day of compound. Bile acids (BA) and phospholipids were measured by mass spectrometry. Compared with untreated mdr2−/− mice, SC-435 treatment for 14 days increased fecal BA excretion by 8-fold, lowered total BA concentration in liver by 65%, reduced total BA and individual hydrophobic BA concentrations in serum by >98%, and decreased plasma ALT, total bilirubin, and serum alkaline phosphatase levels by 86, 93 and 55%, respectively. Liver histology of sclerosing cholangitis improved, and extent of fibrosis decreased concomitant with reduction of hepatic profibrogenic gene expression. Biliary BA concentrations significantly decreased and phospholipids remained low and unchanged with treatment. The phosphatidylcholine/BA ratio in treated mice corrected towards a ratio of 0.28 found in wild type mice, indicating decreased bile toxicity. Hepatic RNAseq studies revealed upregulation of putative anti-inflammatory and antifibrogenic genes, including Ppara and Igf1 and downregulation of several pro-inflammatory genes, including Ccl2 and Lcn2, implicated in leukocyte recruitment. Flow cytometric analysis revealed significant reduction of frequencies of hepatic CD11b+F4/80+ Kupffer cells and CD11b+Gr1+ neutrophils, accompanied by expansion of anti-inflammatory Ly6C− monocytes in treated mdr2−/− mice. Conclusion Inhibition of ASBT reduces BA pool size and retention of hydrophobic BA, favorably alters the biliary PC/BA ratio, profoundly changes the hepatic transcriptome, attenuates

  15. Acute Simvastatin Inhibits KATP Channels of Porcine Coronary Artery Myocytes

    PubMed Central

    Zhang, Qian; Li, Rachel Wai Sum; Kong, Siu Kai; Ngai, Sai Ming; Wan, Song; Ho, Ho Pui; Lee, Simon Ming Yuen; Hoi, Maggie Pui Man; Chan, Shun Wan; Leung, George Pak Heng; Kwan, Yiu Wa

    2013-01-01

    Background Statins (3-hydroxy-3-methyl-glutaryl coenzyme A (HMG-CoA) reductase inhibitors) consumption provides beneficial effects on cardiovascular systems. However, effects of statins on vascular KATP channel gatings are unknown. Methods Pig left anterior descending coronary artery and human left internal mammary artery were isolated and endothelium-denuded for tension measurements and Western immunoblots. Enzymatically-dissociated/cultured arterial myocytes were used for patch-clamp electrophysiological studies and for [Ca2+]i, [ATP]i and [glucose]o uptake measurements. Results The cromakalim (10 nM to 10 µM)- and pinacidil (10 nM to 10 µM)-induced concentration-dependent relaxation of porcine coronary artery was inhibited by simvastatin (3 and 10 µM). Simvastatin (1, 3 and 10 µM) suppressed (in okadaic acid (10 nM)-sensitive manner) cromakalim (10 µM)- and pinacidil (10 µM)-mediated opening of whole-cell KATP channels of arterial myocytes. Simvastatin (10 µM) and AICAR (1 mM) elicited a time-dependent, compound C (1 µM)-sensitive [3H]-2-deoxy-glucose uptake and an increase in [ATP]i levels. A time (2–30 min)- and concentration (0.1–10 µM)-dependent increase by simvastatin of p-AMPKα-Thr172 and p-PP2A-Tyr307 expression was observed. The enhanced p-AMPKα-Thr172 expression was inhibited by compound C, ryanodine (100 µM) and KN93 (10 µM). Simvastatin-induced p-PP2A-Tyr307 expression was suppressed by okadaic acid, compound C, ryanodine, KN93, phloridzin (1 mM), ouabain (10 µM), and in [glucose]o-free or [Na+]o-free conditions. Conclusions Simvastatin causes ryanodine-sensitive Ca2+ release which is important for AMPKα-Thr172 phosphorylation via Ca2+/CaMK II. AMPKα-Thr172 phosphorylation causes [glucose]o uptake (and an [ATP]i increase), closure of KATP channels, and phosphorylation of AMPKα-Thr172 and PP2A-Tyr307 resulted. Phosphorylation of PP2A-Tyr307 occurs at a site downstream of AMPKα-Thr172 phosphorylation. PMID:23799098

  16. Pharmacological Inhibition of Host Heme Oxygenase-1 Suppresses Mycobacterium tuberculosis Infection In Vivo by a Mechanism Dependent on T Lymphocytes.

    PubMed

    Costa, Diego L; Namasivayam, Sivaranjani; Amaral, Eduardo P; Arora, Kriti; Chao, Alex; Mittereder, Lara R; Maiga, Mamoudou; Boshoff, Helena I; Barry, Clifton E; Goulding, Celia W; Andrade, Bruno B; Sher, Alan

    2016-10-25

    Heme oxygenase-1 (HO-1) is a stress response antioxidant enzyme which catalyzes the degradation of heme released during inflammation. HO-1 expression is upregulated in both experimental and human Mycobacterium tuberculosis infection, and in patients it is a biomarker of active disease. Whether the enzyme plays a protective versus pathogenic role in tuberculosis has been the subject of debate. To address this controversy, we administered tin protoporphyrin IX (SnPPIX), a well-characterized HO-1 enzymatic inhibitor, to mice during acute M. tuberculosis infection. These SnPPIX-treated animals displayed a substantial reduction in pulmonary bacterial loads comparable to that achieved following conventional antibiotic therapy. Moreover, when administered adjunctively with antimycobacterial drugs, the HO-1 inhibitor markedly enhanced and accelerated pathogen clearance. Interestingly, both the pulmonary induction of HO-1 expression and the efficacy of SnPPIX treatment in reducing bacterial burden were dependent on the presence of host T lymphocytes. Although M. tuberculosis expresses its own heme-degrading enzyme, SnPPIX failed to inhibit its enzymatic activity or significantly restrict bacterial growth in liquid culture. Together, the above findings reveal mammalian HO-1 as a potential target for host-directed monotherapy and adjunctive therapy of tuberculosis and identify the immune response as a critical regulator of this function.

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

    PubMed Central

    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, JM; Giraldo, J; López-García, JA; Maldonado, R; Plata-Salamán, CR; Vela, JM

    2012-01-01

    BACKGROUND AND PURPOSE The sigma-1 (σ1) 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 σ1 receptor ligands used as pharmacological tools are unclear and the demonstration that σ1 receptor antagonists have efficacy in reversing central sensitization-related pain sensitivity is still missing. EXPERIMENTAL APPROACH The pharmacological properties of a novel σ1 receptor antagonist (S1RA) were first characterized. S1RA was then used to investigate the effect of pharmacological antagonism of σ1 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 σ1 receptor occupancy were measured to substantiate behavioural data. KEY RESULTS 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 σ1 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 σ1 receptors attenuated the wind-up responses in spinal cords sensitized by repetitive nociceptive stimulation. CONCLUSIONS AND IMPLICATIONS These findings contribute to evidence identifying the σ1 receptor as a modulator of activity-induced spinal sensitization and pain hypersensitivity, and suggest σ1 receptor antagonists as potential novel treatments for neuropathic pain. PMID:22404321

  18. Pharmacological inhibition of Polo Like Kinase 2 (PLK2) does not cause chromosomal damage or result in the formation of micronuclei

    SciTech Connect

    Fitzgerald, Kent; Bergeron, Marcelle; Willits, Christopher; Bowers, Simeon; Aubele, Danielle L.; Goldbach, Erich; Tonn, George; Ness, Daniel; Olaharski, Andrew

    2013-05-15

    Polo Like Kinase 2 (PLK2) phosphorylates α-synuclein and is considered a putative therapeutic target for Parkinson's disease. Several lines of evidence indicate that PLK2 is involved with proper centriole duplication and cell cycle regulation, inhibition of which could impact chromosomal integrity during mitosis. The objectives of the series of experiments presented herein were to assess whether specific inhibition of PLK2 is genotoxic and determine if PLK2 could be considered a tractable pharmacological target for Parkinson's disease. Several selective PLK2 inhibitors, ELN 582175 and ELN 582646, and their inactive enantiomers, ELN 582176 and ELN 582647, did not significantly increase the number of micronuclei in the in vitro micronucleus assay. ELN 582646 was administered to male Sprague Dawley rats in an exploratory 14-day study where flow cytometric analysis of peripheral blood identified a dose-dependent increase in the number of micronucleated reticulocytes. A follow-up investigative study demonstrated that ELN 582646 administered to PLK2 deficient and wildtype mice significantly increased the number of peripheral micronucleated reticulocytes in both genotypes, suggesting that ELN 582646-induced genotoxicity is not through the inhibition of PLK2. Furthermore, significant reduction of retinal phosphorylated α-synuclein levels was observed at three non-genotoxic doses, additional data to suggest that pharmacological inhibition of PLK2 is not the cause of the observed genotoxicity. These data, in aggregate, indicate that PLK2 inhibition is a tractable CNS pharmacological target that does not cause genotoxicity at doses and exposures that engage the target in the sensory retina. - Highlights: • Active and inactive enantiomers test negative in the in vitro micronucleus test. • ELN 582646 significantly increased micronuclei at 100 and 300 mg/kg/day doses. • ELN 582646 significantly increased micronuclei in PLK2 knockout mice. • ELN 582646 decreased

  19. Inhibition of gustatory plasticity due to acute nicotine exposure in the nematode Caenorhabditis elegans.

    PubMed

    Matsuura, Tetsuya; Miura, Hitoshi; Nishino, Asuka

    2013-11-01

    The present study investigated the effect of nicotine exposure on gustatory plasticity in the nematode Caenorhabditis elegans. The chemotactic response of wild-type N2 nematodes pre-exposed to 100mM NaCl with 3.0mM nicotine was almost the same as that of mock-conditioned nematodes unexposed to NaCl; however, the response of N2 nematodes pre-exposed to NaCl without nicotine was significantly lower than that of mock-conditioned nematodes. These results indicate that gustatory plasticity is inhibited by acute nicotine exposure. Inhibition of gustatory plasticity was observed when cat-2 mutants with a defect in dopamine biosynthesis were pre-exposed to NaCl with 3.0mM nicotine. Acute nicotine exposure did not cause inhibition of gustatory plasticity in bas-1 mutants, which had defects in both serotonin and dopamine secretion, and tph-1 mutants, which had a defect in serotonin secretion only. However, inhibition of gustatory plasticity was observed when bas-1 and tph-1 mutants were maintained on a growth plate that included serotonin. These results suggest that serotonin signaling plays an essential role in the modulation of the acute effects of nicotine.

  20. Inhibition of autophagy potentiates anticancer property of 20(S)-ginsenoside Rh2 by promoting mitochondria-dependent apoptosis in human acute lymphoblastic leukaemia cells

    PubMed Central

    Wang, Yingnan; Wang, Yuanyuan; Cai, Jianye; Wang, Min; Chen, Qidan; Song, Jia; Yu, Ziqi; Huang, Wei; Fang, Jianpei

    2016-01-01

    Acute lymphoblastic leukaemia (ALL) is the most prevalent childhood malignancy. Although most children with ALL are cured, there is still a group of patients for which therapy fails owing to severe toxicities and drug resistance. Ginsenoside Rh2 (GRh2), a major bioactive component isolated from Panax ginseng, has been shown to have a therapeutic effect on some tumors. However, the molecular mechanisms of cell death induced by 20(S)-GRh2 in ALL cells remains unclear. In this study, we showed that 20(S)-GRh2 inhibited the cell growth and induced mitochondria-dependent apoptosis and autophagy. But it has no cytotoxic effect on human normal blood cells. Furthermore, autophagy plays a protective role in 20(S)-GRh2-induced apoptosis in ALL cell lines and human primary ALL cells. We demonstrated that either genetic or pharmacologic inhibition of autophagy could be more effective in reducing viability and enhancing 20(S)-GRh2-induced toxicity than 20(S)-GRh2 treatment alone. In addition, inhibition of autophagy could aggravate mitochondrial ROS generation and mitochondrial damage, and then accelerate mitochondria-dependent apoptosis. Taken together, these results suggest that inhibition of autophagy can sensitize ALL cells towards 20(S)-GRh2. The appropriate inhibition of autophagy could provide a powerful strategy to increase the potency of 20(S)-GRh2 as a novel anticancer agent for ALL therapy. PMID:27027340

  1. Targeting PDK1 with dichloroacetophenone to inhibit acute myeloid leukemia (AML) cell growth.

    PubMed

    Qin, Lijun; Tian, Yun; Yu, Zhenlong; Shi, Dingbo; Wang, Jingshu; Zhang, Changlin; Peng, Ruoyu; Chen, Xuezhen; Liu, Congcong; Chen, Yiming; Huang, Wenlin; Deng, Wuguo

    2016-01-12

    Pyruvate dehydrogenase kinase-1 (PDK1), a key metabolic enzyme involved in aerobic glycolysis, is highly expressed in many solid tumors. Small molecule compound DAP (2,2-dichloroacetophenone) is a potent inhibitor of PDK1. Whether targeting PDK1 with DAP can inhibit acute myeloid leukemia (AML) and how it works remains unknown. In this study, we evaluated the effect of inhibition of PDK1 with DAP on cell growth, apoptosis and survival in AML cells and identified the underlying mechanisms. We found that treatment with DAP significantly inhibited cell proliferation, increased apoptosis induction and suppressed autophagy in AML cells in vitro, and inhibited tumor growth in an AML mouse model in vivo. We also showed that inhibition of PDK1 with DAP increased the cleavage of pro-apoptotic proteins (PARP and Caspase 3) and decreased the expression of the anti-apoptotic proteins (BCL-xL and BCL-2) and autophagy regulators (ULK1, Beclin-1 and Atg). In addition, we found that DAP inhibited the PI3K/Akt signaling pathway. Furthermore, we demonstrated that PDK1 interacted with ULK1, BCL-xL and E3 ligase CBL-b in AML cells, and DPA treatment could inhibit the interactions. Collectively, our results indicated that targeting PDK1 with DAP inhibited AML cell growth via multiple signaling pathways and suggest that targeting PDK1 may be a promising therapeutic strategy for AMLs.

  2. Enhancement of chemotherapeutic efficacy in hypermethylator breast cancer cells through targeted and pharmacologic inhibition of DNMT3b.

    PubMed

    Sandhu, Rupninder; Rivenbark, Ashley G; Coleman, William B

    2012-01-01

    A subset of primary breast cancers and breast cancer cell lines express a hypermethylation defect (characterized by DNMT hyperactivity and DNMT3b overexpression) which contributes to chemotherapy resistance and provides a target for development of new treatment strategies. The objective of the current study was to determine if targeting the epigenome enhances the sensitivity of breast cancer cells to cytotoxic chemotherapy. Hypermethylator breast cancer cell lines (MDA-MB-453, BT549, and Hs578T) were treated with 250 or 500 nM 5-aza-2'-deoxycytidine (5-aza) and/or were subjected to RNAi-mediated DNMT3b knockdown (KD), and then tested for sensitivity to doxorubicin hydrochloride (DOX), paclitaxel (PAX), and 5-fluorouracil (5-FU). In MDA-MB-453 cells, DNMT3b KD reduces the IC(50) for DOX from 0.086 to 0.048 μM (44% reduction), for PAX from 0.497 to 0.376 nM (24%), and for 5-FU from 0.817 to 0.145 mM (82%). Treatment with 250 nM 5-aza for 7 days did not increase the efficacy of DOX, PAX, or 5-FU, but 7-day treatment with 500 nM 5-aza sensitized cells, reducing the IC(50) for DOX to 0.035 μM (60%), PAX to 0.311 nM (37%), and 5-FU to 0.065 mM (92%). 5-aza treatment of DNMT3b KD cells reduced the IC(50) for DOX to 0.036 μM (59%), for PAX to 0.313 nM (37%) and for 5-FU to 0.067 (92%). Similar trends of enhancement of cell kill were seen in BT549 (13-60%) and Hs578T (29-70%) cells after RNAi-mediated DNMT3b KD and/or treatment with 5-aza. The effectiveness of DOX, PAX, and 5-FU is enhanced through targeted and/or pharmacological inhibition of DNMT3b, strongly suggesting that combined epigenetic and cytotoxic treatment will improve the efficacy of breast cancer chemotherapy.

  3. Cyclic adenosine monophosphate acutely inhibits and chronically stimulates Na/H antiporter in OKP cells.

    PubMed Central

    Cano, A; Preisig, P; Alpern, R J

    1993-01-01

    Parathyroid hormone, dopamine, alpha-adrenergic catecholamines, and angiotensin II regulate renal Na excretion, at least in part through modulation of acute cyclic (c)AMP-induced proximal tubule Na/H antiporter inhibition. The present studies examined the effect of chronic increases in cell cAMP on Na/H antiporter activity in OKP cells. Whereas 8-bromo cAMP acutely inhibited Na/H antiporter activity, chronic application for 6 h led to a 24% increase in Na/H antiporter activity measured 16-20 h after cAMP removal. This chronic persistent activation of the Na/H antiporter required > 2 h exposure. This effect was not a nonspecific effect of 8-bromo cAMP, in that addition of forskolin or forskolin + 3-isobutyl-1-methylxanthine for 6 h also led to a chronic persistent increase in Na/H antiporter activity. Inhibition of protein synthesis with cycloheximide prevented 8-bromo cAMP-induced Na/H antiporter stimulation. Although 8-bromo cAMP addition decreased cell pH by 0.15-0.20 pH U, Na/H antiporter stimulation could be dissociated from cell acidification. In summary, while cAMP acutely inhibits Na/H antiporter activity, it chronically increases antiporter activity. This chronic activation occurs with exogenous addition or endogenous generation of cAMP. These results imply that for hormones that modulate renal Na excretion and proximal tubule Na/H antiporter activity via cAMP and protein kinase A, acute effects may not predict chronic effects. PMID:7691881

  4. Acute Stress Suppresses Synaptic Inhibition and Increases Anxiety via Endocannabinoid Release in the Basolateral Amygdala

    PubMed Central

    Itoga, Christy A.; Fisher, Marc O.; Solomonow, Jonathan; Roltsch, Emily A.; Gilpin, Nicholas W.

    2016-01-01

    Stress and glucocorticoids stimulate the rapid mobilization of endocannabinoids in the basolateral amygdala (BLA). Cannabinoid receptors in the BLA contribute to anxiogenesis and fear-memory formation. We tested for rapid glucocorticoid-induced endocannabinoid regulation of synaptic inhibition in the rat BLA. Glucocorticoid application to amygdala slices elicited a rapid, nonreversible suppression of spontaneous, but not evoked, GABAergic synaptic currents in BLA principal neurons; the effect was also seen with a membrane-impermeant glucocorticoid, but not with intracellular glucocorticoid application, implicating a membrane-associated glucocorticoid receptor. The glucocorticoid suppression of GABA currents was not blocked by antagonists of nuclear corticosteroid receptors, or by inhibitors of gene transcription or protein synthesis, but was blocked by inhibiting postsynaptic G-protein activity, suggesting a postsynaptic nongenomic steroid signaling mechanism that stimulates the release of a retrograde messenger. The rapid glucocorticoid-induced suppression of inhibition was prevented by blocking CB1 receptors and 2-arachidonoylglycerol (2-AG) synthesis, and it was mimicked and occluded by CB1 receptor agonists, indicating it was mediated by the retrograde release of the endocannabinoid 2-AG. The rapid glucocorticoid effect in BLA neurons in vitro was occluded by prior in vivo acute stress-induced, or prior in vitro glucocorticoid-induced, release of endocannabinoid. Acute stress also caused an increase in anxiety-like behavior that was attenuated by blocking CB1 receptor activation and inhibiting 2-AG synthesis in the BLA. Together, these findings suggest that acute stress causes a long-lasting suppression of synaptic inhibition in BLA neurons via a membrane glucocorticoid receptor-induced release of 2-AG at GABA synapses, which contributes to stress-induced anxiogenesis. SIGNIFICANCE STATEMENT We provide a cellular mechanism in the basolateral amygdala (BLA) for

  5. Reversible inhibition of the glycine transporter GlyT2 circumvents acute toxicity while preserving efficacy in the treatment of pain

    PubMed Central

    Mingorance-Le Meur, A; Ghisdal, P; Mullier, B; De Ron, P; Downey, P; Van Der Perren, C; Declercq, V; Cornelis, S; Famelart, M; Van Asperen, J; Jnoff, E; Courade, J P

    2013-01-01

    Background and Purpose Available medications for chronic pain provide only partial relief and often cause unacceptable side effects. There is therefore a need for novel molecular targets to develop new therapeutics with improved efficacy and tolerability. Despite encouraging efficacy data in rodents with inhibitors of the neuronal glycine transporter-2 (GlyT2), there are also some reports of toxicity and their development was discontinued. Experimental Approach In order to clarify the possibility of targeting GlyT2 for the treatment of pain, we have used an integrated approach comprising in vitro pharmacology, selectivity, bioavailability, in vivo efficacy and safety assessment to analyse the properties and efficacy of ALX-1393 and Org-25543, the two published GlyT2 inhibitors from which in vivo data are available. Key Results We report that these compounds have a different set of undesirable properties that limit their usefulness as pharmacological tools. Importantly, we discover that inhibitors of GlyT2 can exert an apparent reversible or irreversible inhibition of the transporter and describe a new class of reversible GlyT2 inhibitors that preserves efficacy while avoiding acute toxicity. Conclusions and Implications Our pharmacological comparison of two closely related GlyT2 inhibitors with different modes of inhibition provides important insights into their safety and efficacy profiles, uncovering that in the presence of a GlyT2 mechanism-based toxicity, reversible inhibitors might allow a tolerable balance between efficacy and toxicity. These findings shed light into the drawbacks associated with the early GlyT2 inhibitors and describe a new mechanism that might serve as the starting point for new drug development. PMID:23962079

  6. Sesamin Attenuates Lipopolysaccharide-Induced Acute Lung Injury by Inhibition of TLR4 Signaling Pathways.

    PubMed

    Qiang, Li; Yuan, Jiang; Shouyin, Jiang; Yulin, Li; Libing, Jiang; Jian-An, Wang

    2016-02-01

    Recent studies suggested that TLR4 signaling pathways played an important role in the development of LPS-induced acute lung injury (ALI). Sesamin, a sesame lignan exacted from sesame seeds, has been shown to exhibit significant anti-inflammatory activity. The purpose of this study was to investigate the anti-inflammatory effects of sesamin on LPS-induced ALI in mice. Mice ALI model was induced by intratracheal instillation of LPS. Sesamin was given 1 h after LPS challenge. Our results showed that sesamin inhibited LPS-induced lung pathological change, edema, and myeloperoxidase (MPO) activity. Sesamin suppressed LPS-induced inflammatory cytokines TNF-α, IL-6, and IL-1β production. Furthermore, sesamin inhibited LPS-induced TLR4 expression and NF-κB activation. In conclusion, the results of this study indicated that sesamin protected against LPS-induced ALI by inhibition of TLR4 signaling pathways.

  7. Inhibiting glutamine uptake represents an attractive new strategy for treating acute myeloid leukemia

    PubMed Central

    Willems, Lise; Jacque, Nathalie; Jacquel, Arnaud; Neveux, Nathalie; Trovati Maciel, Thiago; Lambert, Mireille; Schmitt, Alain; Poulain, Laury; Green, Alexa S.; Uzunov, Madalina; Kosmider, Olivier; Radford-Weiss, Isabelle; Moura, Ivan Cruz; Auberger, Patrick; Ifrah, Norbert; Bardet, Valérie; Chapuis, Nicolas; Lacombe, Catherine; Mayeux, Patrick; Tamburini, Jérôme

    2013-01-01

    Cancer cells require nutrients and energy to adapt to increased biosynthetic activity, and protein synthesis inhibition downstream of mammalian target of rapamycin complex 1 (mTORC1) has shown promise as a possible therapy for acute myeloid leukemia (AML). Glutamine contributes to leucine import into cells, which controls the amino acid/Rag/mTORC1 signaling pathway. We show in our current study that glutamine removal inhibits mTORC1 and induces apoptosis in AML cells. The knockdown of the SLC1A5 high-affinity transporter for glutamine induces apoptosis and inhibits tumor formation in a mouse AML xenotransplantation model. l-asparaginase (l-ase) is an anticancer agent also harboring glutaminase activity. We show that l-ases from both Escherichia coli and Erwinia chrysanthemi profoundly inhibit mTORC1 and protein synthesis and that this inhibition correlates with their glutaminase activity levels and produces a strong apoptotic response in primary AML cells. We further show that l-ases upregulate glutamine synthase (GS) expression in leukemic cells and that a GS knockdown enhances l-ase–induced apoptosis in some AML cells. Finally, we observe a strong autophagic process upon l-ase treatment. These results suggest that l-ase anticancer activity and glutamine uptake inhibition are promising new therapeutic strategies for AML. PMID:24014241

  8. Acute Effects of Whole Body Vibration on Inhibition in Healthy Children

    PubMed Central

    den Heijer, Anne E.; Groen, Yvonne; Fuermaier, Anselm B. M.; van Heuvelen, Marieke J. G.; van der Zee, Eddy A.; Tucha, Lara; Tucha, Oliver

    2015-01-01

    Objectives Whole Body Vibration (WBV) is a passive exercise method known to have beneficial effects on various physical measures. Studies on adults furthermore demonstrated beneficial effects of WBV treatment on cognition (e.g. inhibition). The present study replicated these findings in healthy children and examined acute effects of WBV treatment on inhibition. Methods Fifty-five healthy children (aged 8–13) participated in this within-subject design study. WBV treatment was applied by having the children sit on a chair mounted to a vibrating platform. After each condition (vibration vs. non-vibration), inhibition was measured by using the Stroop Color-Word Interference Test. Repeated measures analyses were applied in order to explore the effects of WBV treatment on inhibition, and correlations were computed between the treatment effect and participant characteristics in order to explore individual differences in treatment sensitivity. Results Three-minute WBV treatments had significant beneficial effects on inhibition in this sample of healthy children. Especially the repeated application (three times) of WBV treatment appeared beneficial for cognition. Stronger WBV treatment effects were correlated with higher intelligence and younger age, but not with symptoms of Attention Deficit Hyperactivity Disorder (ADHD). Conclusions This study demonstrates that especially repeated WBV treatment improves inhibition in healthy children. As this cognitive function is often impaired in children with developmental disorders (e.g. ADHD), future studies should further explore the effects, working mechanism and potential applicability of WBV treatment for this target group. PMID:26524188

  9. Inhibition of HDAC6 protects against rhabdomyolysis-induced acute kidney injury.

    PubMed

    Shi, Yingfeng; Xu, Liuqing; Tang, Jinhua; Fang, Lu; Ma, Shuchen; Ma, Xiaoyan; Nie, Jing; Pi, Xiaoling; Qiu, Andong; Zhuang, Shougang; Liu, Na

    2017-03-01

    Histone deacetylase 6 (HDAC6) inhibition has been reported to protect against ischemic stroke and prolong survival after sepsis in animal models. However, it remains unknown whether HDAC6 inhibition offers a renoprotective effect after acute kidney injury (AKI). In this study, we examined the effect of tubastatin A (TA), a highly selective inhibitor of HDAC6, on AKI in a murine model of glycerol (GL) injection-induced rhabdomyolysis. Following GL injection, the mice developed severe acute tubular injury as indicated by renal dysfunction; expression of neutrophil gelatinase-associated lipocalin (NGAL), an injury marker of renal tubules; and an increase of TdT-mediated dUTP nick-end labeling (TUNEL)-positive tubular cells. These changes were companied by increased HDAC6 expression in the cytoplasm of renal tubular cells. Administration of TA significantly reduced serum creatinine and blood urea nitrogen levels as well as attenuated renal tubular damage in injured kidneys. HDAC6 inhibition also resulted in decreased expression of NGAL, reduced apoptotic cell, and inactivated caspase-3 in the kidney after acute injury. Moreover, injury to the kidney increased phosphorylation of nuclear factor (NF)-κB and expression of multiple cytokines/chemokines including tumor necrotic factor-α and interleukin-6 and monocyte chemoattractant protein-1, as well as macrophage infiltration. Treatment with TA attenuated all those responses. Finally, HDAC6 inhibition reduced the level of oxidative stress by suppressing malondialdehyde (MDA) and preserving expression of superoxide dismutase (SOD) in the injured kidney. Collectively, these data indicate that HDAC6 contributes to the pathogenesis of rhabdomyolysis-induced AKI and suggest that HDAC6 inhibitors have therapeutic potential for AKI treatment.

  10. Acute inhibition of neurosteroid estrogen synthesis suppresses status epilepticus in an animal model

    PubMed Central

    Sato, Satoru M; Woolley, Catherine S

    2016-01-01

    Status epilepticus (SE) is a common neurological emergency for which new treatments are needed. In vitro studies suggest a novel approach to controlling seizures in SE: acute inhibition of estrogen synthesis in the brain. Here, we show in rats that systemic administration of an aromatase (estrogen synthase) inhibitor after seizure onset strongly suppresses both electrographic and behavioral seizures induced by kainic acid (KA). We found that KA-induced SE stimulates synthesis of estradiol (E2) in the hippocampus, a brain region commonly involved in seizures and where E2 is known to acutely promote neural activity. Hippocampal E2 levels were higher in rats experiencing more severe seizures. Consistent with a seizure-promoting effect of hippocampal estrogen synthesis, intra-hippocampal aromatase inhibition also suppressed seizures. These results reveal neurosteroid estrogen synthesis as a previously unknown factor in the escalation of seizures and suggest that acute administration of aromatase inhibitors may be an effective treatment for SE. DOI: http://dx.doi.org/10.7554/eLife.12917.001 PMID:27083045

  11. A systematic review of clinical trials of pharmacological interventions for acute ischaemic stroke (1955-2008) that were completed, but not published in full

    PubMed Central

    2010-01-01

    Background We assessed the prevalence, and potential impact of, trials of pharmacological agents for acute stroke that were completed but not published in full. Failure to publish trial data is to be deprecated as it sets aside the altruism of participants' consent to be exposed to the risks of experimental interventions, potentially biases the assessment of the effects of therapies, and may lead to premature discontinuation of research into promising treatments. Methods We searched the Cochrane Stroke Group's Specialised Register of Trials in June 2008 for completed trials of pharmacological interventions for acute ischaemic stroke, and searched MEDLINE and EMBASE (January 2007 - March 2009) for references to recent full publications. We assessed trial completion status from trial reports, online trials registers and correspondence with experts. Results We identified 940 trials. Of these, 125 (19.6%, 95% confidence interval 16.5-22.6) were completed but not published in full by the point prevalence date. They included 16,058 participants (16 trials had over 300 participants each) and tested 89 different interventions. Twenty-two trials with a total of 4,251 participants reported the number of deaths. In these trials, 636/4251 (15.0%) died. Conclusions Our data suggest that, at the point prevalence date, a substantial body of evidence that was of relevance both to clinical practice in acute stroke and future research in the field was not published in full. Over 16,000 patients had given informed consent and were exposed to the risks of therapy. Responsibility for non-publication lies with investigators, but pharmaceutical companies, research ethics committees, journals and governments can all encourage the timely publication of trial data. PMID:20412562

  12. Inhibition of in vivo histamine metabolism in rats by foodborne and pharmacologic inhibitors of diamine oxidase, histamine N-methyltransferase, and monoamine oxidase

    SciTech Connect

    Hui, J.Y.; Taylor, S.L.

    1985-11-01

    When (/sup 14/C)histamine was administered orally to rats, an average of 80% of the administered radioactivity was recovered in the urine at the end of 24 hr. About 10% of the total dose was excreted via the feces. Analysis of 4-hr urine samples found imidazoleacetic acid to be the predominant metabolite (60.6%), with N tau-methylimidazoleacetic acid (8.6%), N tau-methylhistamine (7.3%), and N-acetylhistamine (4.5%) to be the minor metabolites. Histamine metabolism was inhibited by simultaneous oral administration of aminoguanidine, isoniazid, quinacrine, cadaverine, putrescine, tyramine, and beta-phenylethylamine. The administration of inhibitors resulted in an increased amount of unmetabolized histamine and a decreased amount of metabolites reaching the urine. Pharmacologic inhibitors were found to be more potent and have a longer duration of action than foodborne ones. The inhibitors could potentiate food poisoning caused by histamine by inhibiting its metabolism.

  13. Neutrophil-derived JAML Inhibits Repair of Intestinal Epithelial Injury During Acute Inflammation

    PubMed Central

    Weber, Dominique A.; Sumagin, Ronen; McCall, Ingrid C.; Leoni, Giovanna; Neumann, Philipp A.; Andargachew, Rakieb; Brazil, Jennifer C.; Medina-Contreras, Oscar; Denning, Timothy L.; Nusrat, Asma; Parkos, Charles A.

    2014-01-01

    Neutrophil transepithelial migration (TEM) during acute inflammation is associated with mucosal injury. Using models of acute mucosal injury in-vitro and in-vivo, we describe a new mechanism by which neutrophils infiltrating the intestinal mucosa disrupt epithelial homeostasis. We report that junctional adhesion molecule-like protein (JAML) is cleaved from neutrophil surface by zinc-metalloproteases during TEM. Neutrophil-derived soluble JAML bound to the epithelial tight junction protein coxsackie-adenovirus receptor (CAR) resulting in compromised barrier and inhibition of wound repair, through decreased epithelial proliferation. The deleterious effects of JAML on barrier and wound repair were reversed with an anti-JAML mAb that inhibits JAML-CAR binding. Thus, JAML released from transmigrating neutrophils across inflamed epithelia can promote recruitment of leukocytes and aid in clearance of invading microorganisms. However, sustained release of JAML under pathologic conditions associated with persistence of large numbers of infiltrated neutrophil would compromise intestinal barrier and inhibit mucosal healing. Targeting JAML-CAR interactions may thus improve mucosal healing responses under conditions of dysregulated neutrophil recruitment. PMID:24621992

  14. Kallistatin protects against sepsis-related acute lung injury via inhibiting inflammation and apoptosis.

    PubMed

    Lin, Wei-Chieh; Chen, Chang-Wen; Huang, Yu-Wen; Chao, Lee; Chao, Julie; Lin, Yee-Shin; Lin, Chiou-Feng

    2015-07-22

    Kallistatin, an endogenous plasma protein, exhibits pleiotropic properties in inhibiting inflammation, oxidative stress and apoptosis, as evidenced in various animal models and cultured cells. Here, we demonstrate that kallistatin levels were positively correlated with the concentration of total protein in bronchoalveolar lavage fluids (BALF) from patients with sepsis-related acute respiratory distress syndrome (ARDS), indicating a compensatory mechanism. Lower ratio of kallistatin to total protein in BALF showed a significant trend toward elevated neutrophil counts (P = 0.002) in BALF and increased mortality (P = 0.046). In lipopolysaccharide (LPS)-treated mice, expression of human kallistatin in lung by gene transfer with human kallistatin-encoding plasmid ameliorated acute lung injury (ALI) and reduced cytokine/chemokine levels in BALF. These mice exhibited attenuated lung epithelial apoptosis and decreased Fas/FasL expression compared to the control mice. Mouse survival was improved by kallistatin gene transfer or recombinant human kallistatin treatment after LPS challenge. In LPS-stimulated A549 human lung epithelial cells, kallistatin attenuated apoptosis, down-regulated Fas/FasL signaling, suppressed intracellular reactive oxygen species (ROS) and inhibited ROS-mediated NF-κB activation and inflammation. Furthermore, LPS-induced apoptosis was blocked by antioxidant N-acetylcysteine or NF-κB inhibitor via down-regulating Fas expression. These findings suggest the therapeutic potential of kallistatin for sepsis-related ALI/ARDS.

  15. Inhibition of αvβ6 promotes acute renal allograft rejection in nonhuman primates.

    PubMed

    Lo, D J; Farris, A B; Song, M; Leopardi, F; Anderson, D J; Strobert, E A; Ramakrishnan, S; Turgeon, N A; Mehta, A K; Turnbull, B; Maroni, B; Violette, S M; Kirk, A D

    2013-12-01

    The integrin αvβ6 activates latent transforming growth factor-β (TGF-β) within the kidney and may be a target for the prevention of chronic allograft fibrosis after kidney transplantation. However, TGF-β also has known immunosuppressive properties that are exploited by calcineurin inhibitors (CNIs); thus, the net benefit of αvβ6 inhibition remains undetermined. To assess the acute impact of interference with αvβ6 on acute rejection, we tested a humanized αvβ6-specific monoclonal antibody (STX-100) in a randomized, double-blinded, placebo-controlled nonhuman primate renal transplantation study to evaluate whether αvβ6 blockade alters the risk of acute rejection during CNI-based immunosuppression. Rhesus monkeys underwent renal allotransplantation under standard CNI-based maintenance immunosuppression; 10 biopsy-confirmed rejection-free animals were randomized to receive weekly STX-100 or placebo. Animals treated with STX-100 experienced significantly decreased rejection-free survival compared to placebo animals (p = 0.049). Immunohistochemical analysis confirmed αvβ6 ligand presence, and αvβ6 staining intensity was lower in STX-100-treated animals (p = 0.055), indicating an apparent blockade effect of STX-100. LAP, LTBP-1 and TGF-β were all decreased in animals that rejected on STX-100 compared to those that rejected on standard immunosuppression alone, suggesting a relevant effect of αvβ6 blockade on local TGF-β. These data caution against the use of αvβ6 blockade to achieve TGF-β inhibition in kidney transplantation.

  16. The genetic ablation or pharmacological inhibition of TRPV1 signalling is beneficial for the restoration of quiescent osteoclast activity in ovariectomized mice

    PubMed Central

    Rossi, F; Bellini, G; Torella, M; Tortora, C; Manzo, I; Giordano, C; Guida, F; Luongo, L; Papale, F; Rosso, F; Nobili, B; Maione, S

    2014-01-01

    Background and Purpose Osteoporosis is a condition characterized by a decrease in bone density, which decreases its strength and results in fragile bones. The endocannabinoid/endovanilloid system has been shown to be involved in the regulation of skeletal remodelling. The aim of this study was to investigate the possible modulation of bone mass mediated by the transient receptor potential vanilloid type 1 channel (TRPV1) in vivo and in vitro. Experimental Approach A multidisciplinary approach, including biomolecular, biochemical and morphological analysis, was used to investigate the involvement of TRPV1 in changes in bone density in vivo and osteoclast activity in vitro, in wild-type and Trpv1−/− mice, that had undergone ovariectomy or had a sham operation. Key Results Genetic deletion of Trpv1 as well as pharmacological inhibition/desensitization of TRPV1 signalling dramatically reduced the osteoclast activity in vitro and prevented the ovariectomy-induced bone loss in vivo, whereas the expression of cannabinoid type 2 (CB2) receptors was increased. Conclusions and Implications These findings highlight the pivotal role TRPV1 channels play in bone resorption and suggest a possible cross-talk between TRPV1 and CB2 receptors. Based on these results, hybrid compounds acting on both TRPV1 and CB2 receptors in an opposite manner could provide a future pharmacological tool for the treatment of diseases associated with disturbances in the bone remodelling process. Linked Articles This article is part of a themed section on the pharmacology of TRP channels. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-10 PMID:24308803

  17. Edaravone attenuates brain damage in rats after acute CO poisoning through inhibiting apoptosis and oxidative stress.

    PubMed

    Li, Qin; Bi, Ming Jun; Bi, Wei Kang; Kang, Hai; Yan, Le Jing; Guo, Yun-Liang

    2016-03-01

    Acute carbon monoxide (CO) poisoning is the most common cause of death from poisoning all over the world and may result in neuropathologic and neurophysiologic changes. Acute brain damage and delayed encephalopathy are the most serious complication, yet their pathogenesis is poorly understood. The present study aimed to evaluate the neuroprotective effects of Edaravone against apoptosis and oxidative stress after acute CO poisoning. The rat model of CO poisoning was established in a hyperbaric oxygen chamber by exposed to CO. Ultrastructure changes were observed by transmission electron microscopy (TEM). TUNEL stain was used to assess apoptosis. Immunohistochemistry and immunofluorescence double stain were used to evaluate the expression levels of heme oxygenase-1 (HO-1) and nuclear factor erythroid 2-related factor 2 (Nrf-2) protein and their relationship. By dynamically monitored the carboxyhemoglobin (HbCO) level in blood, we successfully established rat model of severe CO poisoning. Ultrastructure changes, including chromatin condensation, cytoplasm dissolution, vacuoles formation, nucleus membrane and cell organelles decomposition, could be observed after CO poisoning. Edaravone could improve the ultrastructure damage. CO poisoning could induce apoptosis. Apoptotic cells were widely distributed in cortex, striatum and hippocampus. Edaravone treatment attenuated neuronal apoptosis as compared with the poisoning group (P < 0.01). Basal expressions of HO-1 and Nrf-2 proteins were found in normal brain tissue. CO poisoning could activate HO-1/Nrf-2 pathway, start oxidative stress response. After the administration of Edaravone, the expression of HO-1 and Nrf-2 significantly increased (P < 0.01). These findings suggest that Edaravone may inhibit apoptosis, activate the Keapl-Nrf/ARE pathway, and thus improve the ultrastructure damage and neurophysiologic changes following acute CO poisoning.

  18. Effect of inhibition of prostaglandin E2 production on pancreatic infection in experimental acute pancreatitis

    PubMed Central

    Coelho, Ana Maria M.; Sampietre, Sandra; Patzina, Rosely; Jukemura, Jose; Cunha, Jose Eduardo M.; Machado, Marcel C.C.

    2007-01-01

    Objective. Acute pancreatitis is one the important causes of systemic inflammatory response syndrome (SIRS). SIRS results in gut barrier dysfunction that allows bacterial translocation and pancreatic infection to occur. Indomethacin has been used to reduce inflammatory process and bacterial translocation in experimental models. The purpose of this study was to determine the effect of inhibition of prostaglandin E2 (PGE2) production on pancreatic infection. Materials and methods. An experimental model of severe acute pancreatitis (AP) was utilized. The animals were divided into three groups: sham (surgical procedure without AP induction); pancreatitis (AP induction); and indomethacin (AP induction plus administration of 3 mg/kg of indomethacin). Serum levels of interleukin (IL)-6 and IL-10, PGE2, and tumor necrosis factor (TNF)-α were measured 2 h after the induction of AP. We analyzed the occurrence of pancreatic infection with bacterial cultures performed 24 h after the induction of AP. The occurrence of pancreatic infection (considered positive when the CFU/g was >105), pancreatic histologic analysis, and mortality rate were studied. Results. In spite of the reduction of IL-6, IL-10, and PGE2 levels in the indomethacin group, TNF-α level, bacterial translocation, and pancreatic infection were not influenced by administration of indomethacin. The inhibition of PGE2 production did not reduce pancreatic infection, histologic score, or mortality rate. Conclusion. The inhibition of PGE2 production was not able to reduce the occurrence of pancreatic infection and does not have any beneficial effect in this experimental model. Further investigations will be necessary to discover a specific inhibitor that would make it possible to develop an anti-inflammatory therapy. PMID:18345325

  19. Hydrogen-rich saline attenuates acute renal injury in sodium taurocholate-induced severe acute pancreatitis by inhibiting ROS and NF-κB pathway.

    PubMed

    Shi, Qiao; Liao, Kang-Shu; Zhao, Kai-Liang; Wang, Wei-Xing; Zuo, Teng; Deng, Wen-Hong; Chen, Chen; Yu, Jia; Guo, Wen-Yi; He, Xiao-Bo; Abliz, Ablikim; Wang, Peng; Zhao, Liang

    2015-01-01

    Hydrogen (H2), a new antioxidant, was reported to reduce (•)OH and ONOO(-) selectively and inhibit certain proinflammatory mediators to product, without disturbing metabolic redox reactions or ROS involved in cell signaling. We herein aim to explore its protective effects on acute renal injury in sodium taurocholate-induced acute pancreatitis and its possible mechanisms. Rats were injected with hydrogen-rich saline (HRS group) or normal saline (SO and SAP group) through tail intravenously (6 mL/kg) and compensated subcutaneously (20 mL/kg) after successful modeling. Results showed that hydrogen-rich saline attenuated the following: (1) serum Cr and BUN, (2) pancreatic and renal pathological injuries, (3) renal MDA, (4) renal MPO, (5) serum IL-1β, IL-6, and renal TNF-α, HMGB1, and (6) tyrosine nitration, IκB degradation, and NF-κB activation in renal tissues. In addition, it increased the level of IL-10 and SOD activity in renal tissues. These results proved that hydrogen-rich saline attenuates acute renal injury in sodium taurocholate-induced acute pancreatitis, presumably because of its detoxification activity against excessive ROS, and inhibits the activation of NF-κB by affecting IκB nitration and degradation. Our findings highlight the potential value of hydrogen-rich saline as a new therapeutic method on acute renal injury in severe acute pancreatitis clinically.

  20. Inhibition of Angiotensin-II Production Increases Susceptibility to Acute Ischemia/Reperfusion Arrhythmia

    PubMed Central

    Taskin, Eylem; Tuncer, Kadir Ali; Guven, Celal; Kaya, Salih Tunc; Dursun, Nurcan

    2016-01-01

    Background Myocardial ischemia and reperfusion lead to impairment of electrolyte balance and, eventually, lethal arrhythmias. The aim of this study was to investigate the effects of pharmacological inhibition of angiotensin-II (Ang-II) production on heart tissue with ischemia-reperfusion damage, arrhythmia, and oxidative stress. Material/Methods Rats were divided into 4 groups: only ischemia/reperfusion (MI/R), captopril (CAP), aliskiren (AL), and CAP+AL. The drugs were given by gavage 30 min before anesthesia. Blood pressure and electrocardiography (ECG) were recorded during MI/R procedures. The heart tissue and plasma was kept so as to evaluate the total oxidant (TOS), antioxidant status (TAS), and creatine kinase-MB (CK-MB). Results Creatine kinase-MB was not different among the groups. Although TAS was not affected by inhibition of Ang-II production, TOS was significantly lower in the CAP and/or AL groups than in the MI/R group. Furthermore, oxidative stress index was significantly attenuated in the CAP and/or AL groups. Captopril significantly increased the duration of VT during ischemia; however, it did not have any effect on the incidence of arrhythmias. During reperfusion periods, aliskiren and its combinations with captopril significantly reduced the incidence of other types of arrhythmias. Captopril alone had no effect on the incidence of arrhythmias, but significantly increased arrhythmias score and durations of arrhythmias during reperfusion. MAP and heart rate did not show changes in any groups during ischemic and reperfusion periods. Conclusions Angiotensin-II production appears to be associated with elevated levels of reactive oxygen species, but Ang-II inhibitions increases arrhythmia, mainly by initiating ventricular ectopic beats. PMID:27889788

  1. Pharmacological Evidence that Histamine H3 Receptors Mediate Histamine-Induced Inhibition of the Vagal Bradycardic Out-flow in Pithed Rats.

    PubMed

    García, Mónica; García-Pedraza, José Ángel; Villalón, Carlos M; Morán, Asunción

    2016-02-01

    In vivo stimulation of cardiac vagal neurons induces bradycardia by acetylcholine (ACh) release. As vagal release of ACh may be modulated by autoreceptors (muscarinic M2 ) and heteroreceptors (including serotonin 5-HT1 ), this study has analysed the pharmacological profile of the receptors involved in histamine-induced inhibition of the vagal bradycardic out-flow in pithed rats. For this purpose, 180 male Wistar rats were pithed, artificially ventilated and pre-treated (i.v.) with 1 mg/kg atenolol, followed by i.v. administration of physiological saline (1 ml/kg), histamine (10, 50, 100 and 200 μg/kg) or the selective histamine H1 (2-pyridylethylamine), H2 (dimaprit), H3 (methimepip) and H4 (VUF 8430) receptor agonists (1, 10, 50 and 100 μg/kg each). Under these conditions, electrical stimulation (3, 6 and 9 Hz; 15 ± 3 V and 1 ms) of the vagus nerve resulted in frequency-dependent bradycardic responses, which were (i) unchanged during the infusions of saline, 2-pyridylethylamine, dimaprit or VUF 8430; and (ii) dose-dependently inhibited by histamine or methimepip. Moreover, the inhibition of the bradycardia caused by 50 μg/kg of either histamine or methimepip (which failed to inhibit the bradycardic responses to i.v. bolus injections of acetylcholine; 1-10 μg/kg) was abolished by the H3 receptor antagonist JNJ 10181457 (1 mg/kg, i.v.). In conclusion, our results suggest that histamine-induced inhibition of the vagal bradycardic out-flow in pithed rats is mainly mediated by pre-junctional activation of histamine H3 receptors, as previously demonstrated for the vasopressor sympathetic out-flow and the vasodepressor sensory CGRPergic (calcitonin gene-related peptide) out-flow.

  2. Pharmacological evidence that histamine H3 receptors inhibit the vasodepressor responses by selective stimulation of the rat perivascular sensory CGRPergic outflow.

    PubMed

    Manrique-Maldonado, Guadalupe; Altamirano-Espinoza, Alain H; Marichal-Cancino, Bruno A; Rivera-Mancilla, Eduardo; Avilés-Rosas, Victor; Villalón, Carlos M

    2015-05-05

    This study has investigated whether pharmacological activation of Gi/o coupled histamine H3/H4 receptors inhibits the rat vasodepressor sensory outflow. For this purpose, 100 male Wistar rats were pithed, artificially ventilated and pretreated (i.v.) with: 25mg/kg gallamine, 2mg/kg/min hexamethonium and 20μg/kg/min methoxamine, followed by i.v. continuous infusions of physiological saline (0.02ml/min) or immepip (3.1, 10 or 31μg/kg/min; a histamine H3/H4 receptor agonist). Under these conditions, electrical stimulation (0.56-5.6Hz; 50V and 2ms) of the spinal cord (T9-T12) resulted in frequency-dependent vasodepressor responses, which were: (i) unchanged during the infusions of saline or immepip (3.1μg/kg/min); and (ii) significantly but, surprisingly, not dose-dependently inhibited by 10 and 31μg/kg/min immepip. Moreover, the sensory-inhibition by 10μg/kg/min immepip (which failed to inhibit the vasodepressor responses by i.v. bolus injections of α-CGRP; 0.1-1µg/kg) was: (i) essentially unaltered after i.v. administration of saline (1ml/kg) or blocking doses of the antagonists ketotifen (100μg/kg; H1), ranitidine (1000μg/kg; H2) or JNJ7777120 (310μg/kg; H4); and (ii) abolished after i.v. thioperamide (310µg/kg; H3). In conclusion, our results suggest that immepip-induced inhibition of the vasodepressor sensory outflow is mainly mediated by prejunctional activation of histamine H3 receptors.

  3. Inhibition of peroxynitrite-mediated DNA strand cleavage and hydroxyl radical formation by aspirin at pharmacologically relevant concentrations: Implications for cancer intervention

    SciTech Connect

    Chen, Wei; Zhu, Hong; Jia, Zhenquan; Li, Jianrong; Misra, Hara P.; Zhou, Kequan; Li, Yunbo

    2009-12-04

    Epidemiological studies have suggested that the long-term use of aspirin is associated with a decreased incidence of human malignancies, especially colorectal cancer. Since accumulating evidence indicates that peroxynitrite is critically involved in multistage carcinogenesis, this study was undertaken to investigate the ability of aspirin to inhibit peroxynitrite-mediated DNA damage. Peroxynitrite and its generator 3-morpholinosydnonimine (SIN-1) were used to cause DNA strand breaks in {phi}X-174 plasmid DNA. We demonstrated that the presence of aspirin at concentrations (0.25-2 mM) compatible with amounts in plasma during chronic anti-inflammatory therapy resulted in a significant inhibition of DNA cleavage induced by both peroxynitrite and SIN-1. Moreover, the consumption of oxygen caused by 250 {mu}M SIN-1 was found to be decreased in the presence of aspirin, indicating that aspirin might affect the auto-oxidation of SIN-1. Furthermore, EPR spectroscopy using 5,5-dimethylpyrroline-N-oxide (DMPO) as a spin trap demonstrated the formation of DMPO-hydroxyl radical adduct (DMPO-OH) from authentic peroxynitrite, and that aspirin at 0.25-2 mM potently diminished the radical adduct formation in a concentration-dependent manner. Taken together, these results demonstrate for the first time that aspirin at pharmacologically relevant concentrations can inhibit peroxynitrite-mediated DNA strand breakage and hydroxyl radical formation. These results may have implications for cancer intervention by aspirin.

  4. The effect of therapeutic drugs and other pharmacologic agents on activity of porphobilinogen deaminase, the enzyme that is deficient in intermittent acute porphyria.

    PubMed

    Tishler, P V

    1999-01-01

    Drugs and toxins precipitate life-threatening acute attacks in patients with intermittent acute porphyria. These materials may act by directly inhibiting enzyme activity, thus further reducing porphobilinogen (PBG) deaminase activity below the ca. 50% level that results from the gene defect. To test this, we studied the effects of drugs that precipitate acute attacks (lead, phenobarbital, griseofulvin, phenytoin, sulfanilamide, sulfisoxazole, 17alpha-ethinyl estradiol, 5beta-pregnan-3alpha-ol-20-one), drugs that are safe (lithium, magnesium, chlorpromazine, promethazine), and those with uncertain effects (ethyl alcohol, imipramine, diazepam, haloperidol) on activity of PBG deaminase in vitro and in vivo. In the in vitro studies, of PBG deaminase from human erythrocytes from normals and individuals with IAP, only lead (> or = .01 mM) inhibited enzyme activity. Chlorpromazine (> or = .01 mM), promethazine (> or = .01 mM) and imipramine (1 mM) seemed to increase enzyme activity. In most in vivo experiments, male rats were injected intraperitoneally with test material twice daily for 3 days and once on day four; and erythrocyte and hepatic PBG deaminase activity was assayed thereafter. Effects on enzyme activity were observed only with 17alpha-ethinyl estradiol (0.05 microg/kg/day; reduction of 11% in erythrocyte enzyme [NS], and of 20% in liver enzyme [P=.02]), and imipramine (12.5 mg/kg/day; reduction in erythrocyte enzyme activity of 13% [P<.001]). Rats given lead acetate in their drinking water (10 mg/ml) for the first 60 days of life, resulting in high blood and liver lead levels, had increased erythrocyte PBG deaminase (167% of control; P=.004). Thus, enzyme inhibition by lead in vitro was not reflected in a similar in vivo inhibition. The only inhibitory effects in vivo, with ethinyl estradiol and imipramine, appear to be mild and biologically inconsequential. We conclude that inhibition of PBG deaminase activity by materials that precipitate acute attacks is an

  5. Resveratrol attenuates acute kidney injury by inhibiting death receptor-mediated apoptotic pathways in a cisplatin-induced rat model

    PubMed Central

    Hao, Qiufa; Xiao, Xiaoyan; Zhen, Junhui; Feng, Jinbo; Song, Chun; Jiang, Bei; Hu, Zhao

    2016-01-01

    Acute kidney injury is a clinical syndrome characterized by a loss of renal function and acute tubular necrosis. Resveratrol exerts a wide range of pharmacological effects based on its anti-inflammatory, antioxidant and cytoprotective properties. The present study aimed to evaluate whether resveratrol attenuates acute kidney injury in a cisplatin-induced rat model and to investigate the potential mechanisms involved. Rats were randomly divided into four treatment groups: Control, cisplatin, resveratrol, and cisplatin plus resveratrol. Rats exposed to cisplatin displayed acute kidney injury, identified by analysis of renal function and histopathological observation. Resveratrol significantly ameliorated the increased serum creatinine, blood urea nitrogen, renal index and histopathological damage induced by cisplatin. Furthermore, compared with untreated control animals, cisplatin lead to significantly increased expression of Fas ligand, tumor necrosis factor-α (TNF-α), caspase-8 and Bcl-2 associated protein X apoptosis regulator (Bax), and decreased expression of anti-apoptosis regulators, BH3 interacting domain death agonist (BID) and B cell lymphoma 2 apoptosis regulator (Bcl-2). Administration of resveratrol significantly reversed the cisplatin-induced alteration in these apoptosis-associated proteins. In conclusion, these findings suggest that resveratrol attenuates cisplatin-induced acute kidney injury through inactivation of the death receptor-mediated apoptotic pathway, and may provide a new therapeutic strategy to ameliorate the process of acute kidney injury. PMID:27600998

  6. Inhibiting glutaminase in acute myeloid leukemia: metabolic dependency of selected AML subtypes.

    PubMed

    Matre, Polina; Velez, Juliana; Jacamo, Rodrigo; Qi, Yuan; Su, Xiaoping; Cai, Tianyu; Chan, Steven M; Lodi, Alessia; Sweeney, Shannon R; Ma, Helen; Davis, Richard Eric; Baran, Natalia; Haferlach, Torsten; Su, Xiaohua; Flores, Elsa Renee; Gonzalez, Doriann; Konoplev, Sergej; Samudio, Ismael; DiNardo, Courtney; Majeti, Ravi; Schimmer, Aaron D; Li, Weiqun; Wang, Taotao; Tiziani, Stefano; Konopleva, Marina

    2016-11-29

    Metabolic reprogramming has been described as a hallmark of transformed cancer cells. In this study, we examined the role of the glutamine (Gln) utilization pathway in acute myeloid leukemia (AML) cell lines and primary AML samples. Our results indicate that a subset of AML cell lines is sensitive to Gln deprivation. Glutaminase (GLS) is a mitochondrial enzyme that catalyzes the conversion of Gln to glutamate. One of the two GLS isoenzymes, GLS1 is highly expressed in cancer and encodes two different isoforms: kidney (KGA) and glutaminase C (GAC). We analyzed mRNA expression of GLS1 splicing variants, GAC and KGA, in several large AML datasets and identified increased levels of expression in AML patients with complex cytogenetics and within specific molecular subsets. Inhibition of glutaminase by allosteric GLS inhibitor bis-2-(5-phenylacetamido-1, 2, 4-thiadiazol-2-yl) ethyl sulfide or by novel, potent, orally bioavailable GLS inhibitor CB-839 reduced intracellular glutamate levels and inhibited growth of AML cells. In cell lines and patient samples harboring IDH1/IDH2 (Isocitrate dehydrogenase 1 and 2) mutations, CB-839 reduced production of oncometabolite 2-hydroxyglutarate, inducing differentiation. These findings indicate potential utility of glutaminase inhibitors in AML therapy, which can inhibit cell growth, induce apoptosis and/or differentiation in specific leukemia subtypes.

  7. Inhibition of Ras signalling reduces neutrophil infiltration and tissue damage in severe acute pancreatitis.

    PubMed

    Yu, Changhui; Merza, Mohammed; Luo, Lingtao; Thorlacius, Henrik

    2015-01-05

    Neutrophil recruitment is known to be a rate-limiting step in mediating tissue injury in severe acute pancreatitis (AP). However, the signalling mechanisms controlling inflammation and organ damage in AP remain elusive. Herein, we examined the role of Ras signalling in AP. Male C57BL/6 mice were treated with a Ras inhibitor (farnesylthiosalicylic acid, FTS) before infusion of taurocholate into the pancreatic duct. Pancreatic and lung tissues as well as blood were collected 24 h after pancreatitis induction. Pretreatment with FTS decreased serum amylase levels by 82% and significantly attenuated acinar cell necrosis, tissue haemorrhage and oedema formation in taurocholate-induced pancreatitis. Inhibition of Ras signalling reduced myeloperoxidase (MPO) levels in the inflamed pancreas by 42%. In addition, administration of FTS decreased pancreatic levels of CXC chemokines as well as circulating levels of interleukin-6 and high-mobility group box 1 in animals exposed to taurocholate. Moreover, treatment with FTS reduced taurocholate-induced MPO levels in the lung. Inhibition of Ras signalling had no effect on neutrophil expression of Mac-1 in mice with pancreatitis. Moreover, FTS had no direct impact on trypsin activation in isolated pancreatic acinar cells. These results indicate that Ras signalling controls CXC chemokine formation, neutrophil recruitment and tissue injury in severe AP. Thus, our findings highlight a new signalling mechanism regulating neutrophil recruitment in the pancreas and suggest that inhibition of Ras signalling might be a useful strategy to attenuate local and systemic inflammation in severe AP.

  8. Inhibiting glutaminase in acute myeloid leukemia: metabolic dependency of selected AML subtypes

    PubMed Central

    Jacamo, Rodrigo; Qi, Yuan; Su, Xiaoping; Cai, Tianyu; Chan, Steven M.; Lodi, Alessia; Sweeney, Shannon R.; Ma, Helen; Davis, Richard Eric; Baran, Natalia; Haferlach, Torsten; Su, Xiaohua; Flores, Elsa Renee; Gonzalez, Doriann; Konoplev, Sergej; Samudio, Ismael; DiNardo, Courtney; Majeti, Ravi; Schimmer, Aaron D.; Li, Weiqun; Wang, Taotao; Tiziani, Stefano; Konopleva, Marina

    2016-01-01

    Metabolic reprogramming has been described as a hallmark of transformed cancer cells. In this study, we examined the role of the glutamine (Gln) utilization pathway in acute myeloid leukemia (AML) cell lines and primary AML samples. Our results indicate that a subset of AML cell lines is sensitive to Gln deprivation. Glutaminase (GLS) is a mitochondrial enzyme that catalyzes the conversion of Gln to glutamate. One of the two GLS isoenzymes, GLS1 is highly expressed in cancer and encodes two different isoforms: kidney (KGA) and glutaminase C (GAC). We analyzed mRNA expression of GLS1 splicing variants, GAC and KGA, in several large AML datasets and identified increased levels of expression in AML patients with complex cytogenetics and within specific molecular subsets. Inhibition of glutaminase by allosteric GLS inhibitor bis-2-(5-phenylacetamido-1, 2, 4-thiadiazol-2-yl) ethyl sulfide or by novel, potent, orally bioavailable GLS inhibitor CB-839 reduced intracellular glutamate levels and inhibited growth of AML cells. In cell lines and patient samples harboring IDH1/IDH2 (Isocitrate dehydrogenase 1 and 2) mutations, CB-839 reduced production of oncometabolite 2-hydroxyglutarate, inducing differentiation. These findings indicate potential utility of glutaminase inhibitors in AML therapy, which can inhibit cell growth, induce apoptosis and/or differentiation in specific leukemia subtypes. PMID:27806325

  9. Acute inhibition of central c-Jun N-terminal kinase restores hypothalamic insulin signalling and alleviates glucose intolerance in diabetic mice.

    PubMed

    Benzler, J; Ganjam, G K; Legler, K; Stöhr, S; Krüger, M; Steger, J; Tups, A

    2013-05-01

    The hypothalamus has been identified as a main insulin target tissue for regulating normal body weight and glucose metabolism. Recent observations suggest that c-Jun-N-terminal kinase (JNK)-signalling plays a crucial role in the development of obesity and insulin resistance because neuronal JNK-1 ablation in the mouse prevented high-fat diet-induced obesity (DIO) and increased energy expenditure, as well as insulin sensitivity. In the present study, we investigated whether central JNK inhibition is associated with sensitisation of hypothalamic insulin signalling in mice fed a high-fat diet for 3 weeks and in leptin-deficient mice. We determined whether i.c.v. injection of a pharmacological JNK-inhibitor (SP600125) improved impaired glucose homeostasis. By immunohistochemistry, we first observed that JNK activity was increased in the arcuate nucleus (ARC) and the ventromedial hypothalamus (VMH) in both mouse models, relative to normoglycaemic controls. This suggests that up-regulation of JNK in these regions is associated with glucose intolerance and obesity, independent of leptin levels. Acute i.c.v. injection of SP600125 ameliorated glucose tolerance within 30 min in both leptin-deficient and DIO mice. Given the acute nature of i.c.v. injections, these effects cannot be attributed to changes in food intake or energy balance. In a hypothalamic cell line, and in the ARC and VMH of leptin-deficient mice, JNK inhibition by SP600125 consistently improved impaired insulin signalling. This was determined by a reduction of phospho-insulin receptor substrate-1 [IRS-1(Ser612)] protein in a hypothalamic cell line and a decline in the number of pIRS-1(Ser612) immunoreactive cells in the ARC and VMH. Serine 612 phosphorylation of IRS-1 is assumed to negatively regulate insulin signalling. In leptin-deficient mice, in both nuclei, central inhibition of JNK increased the number of cells immunoreactive for phospho-Akt (Ser473) and phospho-GSK-3β (Ser9), which are important

  10. Pharmacological Inhibition of c-Jun N-terminal Kinase Reduces Food Intake and Sensitizes Leptin's Anorectic Signaling Actions.

    PubMed

    Gao, Su; Howard, Shannon; LoGrasso, Philip V

    2017-02-06

    The role for c-Jun N-terminal Kinase (JNK) in the control of feeding and energy balance is not well understood. Here, by use of novel and highly selective JNK inhibitors, we investigated the actions of JNK in the control of feeding and body weight homeostasis. In lean mice, intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) administration of SR-3306, a brain-penetrant and selective pan-JNK (JNK1/2/3) inhibitor, reduced food intake and body weight. Moreover, i.p. and i.c.v. administrations of SR11935, a brain-penetrant and JNK2/3 isoform-selective inhibitor, exerted similar anorectic effects as SR3306, which suggests JNK2 or JNK3 mediates aspect of the anorectic effect by pan-JNK inhibition. Furthermore, daily i.p. injection of SR3306 (7 days) prevented the increases in food intake and weight gain in lean mice upon high-fat diet feeding, and this injection paradigm reduced high-fat intake and obesity in diet-induced obese (DIO) mice. In the DIO mice, JNK inhibition sensitized leptin's anorectic effect, and enhanced leptin-induced STAT3 activation in the hypothalamus. The underlying mechanisms likely involve the downregulation of SOCS3 by JNK inhibition. Collectively, our data suggest that JNK activity promotes positive energy balance, and the therapeutic intervention inhibiting JNK activities represents a promising approach to ameliorate diet-induced obesity and leptin resistance.

  11. Pharmacological inhibition of outwardly rectifying Cl- currents in rat peritoneal mast cells: a comparison of different stilbene derivatives.

    PubMed

    Roloff, Tim; Ziegler, Albrecht; Heber, Dieter; Seebeck, Jörg

    2003-10-08

    Diethylstilbestrol and other stilbene derivatives can provide some inhibition of the outwardly rectifying Cl- current (I(Cl-,OR)) in rat peritoneal mast cells. In order to elucidate structure-activity relationships of diethylstilbestrol, 12 stilbenes as well as 17beta-estradiol and hexestrol were tested in rat peritoneal mast cells using the nystatin-perforated patch approach of the whole-cell patch-clamp technique. Since trans-stilbene showed no effect, the substituents of diethylstilbestrol must be of importance. The introduction of only one hydroxy group in trans-stilbene produced potent inhibition of the I(Cl-,OR) (IC50: 3.3 microM). But in contrast, resveratrol with hydroxy groups at positions 4, 3', and 5' as well as methoxy substituted stilbene derivatives and 17beta-estradiol were ineffective. On the other hand, hexestrol potently inhibited I(Cl-,OR) indicating that the aromatic ring systems can also be connected by an ethyl bridge. In summary, a hydroxy group at position 4 (or 4') is a prerequisite for diethylstilbestrol-mediated inhibition of I(Cl-,OR).

  12. Pharmacological Inhibition of Monoacylglycerol O-Acyltransferase 2 Improves Hyperlipidemia, Obesity, and Diabetes by Change in Intestinal Fat Utilization

    PubMed Central

    Take, Kazumi; Mochida, Taisuke; Maki, Toshiyuki; Satomi, Yoshinori; Hirayama, Megumi; Nakakariya, Masanori; Amano, Nobuyuki; Adachi, Ryutaro; Sato, Kenjiro; Kitazaki, Tomoyuki; Takekawa, Shiro

    2016-01-01

    Monoacylglycerol O-acyltransferase 2 (MGAT2) catalyzes the synthesis of diacylglycerol (DG), a triacylglycerol precursor and potential peripheral target for novel anti-obesity therapeutics. High-throughput screening identified lead compounds with MGAT2 inhibitory activity. Through structural modification, a potent, selective, and orally bioavailable MGAT2 inhibitor, compound A (compA), was discovered. CompA dose-dependently inhibited postprandial increases in plasma triglyceride (TG) levels. Metabolic flux analysis revealed that compA inhibited triglyceride/diacylglycerol resynthesis in the small intestine and increased free fatty acid and acyl-carnitine with shorter acyl chains than originally labelled fatty acid. CompA decreased high-fat diet (HFD) intake in C57BL/6J mice. MGAT2-null mice showed a similar phenotype as compA-treated mice and compA did not suppress a food intake in MGAT2 KO mice, indicating that the anorectic effects were dependent on MGAT2 inhibition. Chronic administration of compA significantly prevented body weight gain and fat accumulation in mice fed HFD. MGAT2 inhibition by CompA under severe diabetes ameliorated hyperglycemia and fatty liver in HFD-streptozotocin (STZ)-treated mice. Homeostatic model assessments (HOMA-IR) revealed that compA treatment significantly improved insulin sensitivity. The proximal half of the small intestine displayed weight gain following compA treatment. A similar phenomenon has been observed in Roux-en-Y gastric bypass-treated animals and some studies have reported that this intestinal remodeling is essential to the anti-diabetic effects of bariatric surgery. These results clearly demonstrated that MGAT2 inhibition improved dyslipidemia, obesity, and diabetes, suggesting that compA is an effective therapeutic for obesity-related metabolic disorders. PMID:26938273

  13. Level of response and safety of pharmacological monotherapy in the treatment of acute bipolar I disorder phases: a systematic review and meta-analysis

    PubMed Central

    Tamayo, Jorge M.; Zarate, Carlos A.; Vieta, Eduard; Vázquez, Gustavo; Tohen, Mauricio

    2010-01-01

    In recent years, combinations of pharmacological treatments have become common for the treatment of bipolar disorder type I (BP I); however, this practice is usually not evidence-based and rarely considers monotherapy drug regimen (MDR) as an option in the treatment of acute phases of BP I. Therefore, we evaluated comparative data of commonly prescribed MDRs for both manic and depressive phases of BP I. Medline, PsycINFO, EMBASE, the Cochrane Library, the ClinicalStudyResults.org and other data sources were searched from 1949 to March 2009 for placebo and active controlled randomized clinical trials (RCTs). Risk ratios (RRs) for response, remission, and discontinuation rates due to adverse events (AEs), lack of efficacy, or discontinuation due to any cause, and the number needed to treat or harm (NNT or NNH) were calculated for each medication individually and for all evaluable trials combined. The authors included 31 RCTs in the analyses comparing a MDR with placebo or with active treatment for acute mania, and 9 RCTs comparing a MDR with placebo or with active treatment for bipolar depression. According to the collected evidence, most of the MDRs when compared to placebo showed significant response and remission rates in acute mania. In the case of bipolar depression only quetiapine and, to a lesser extent, olanzapine showed efficacy as MDR. Overall, MDRs were well tolerated with low discontinuation rates due to any cause or AE, although AE profiles differed among treatments. We concluded that most MDRs were efficacious and safe in the treatment of manic episodes, but very few MDRs have demonstrated being efficacious for bipolar depressive episodes. PMID:20128953

  14. The arsenic-based cure of acute promyelocytic leukemia promotes cytoplasmic sequestration of PML and PML/RARA through inhibition of PML body recycling.

    PubMed

    Lång, Emma; Grudic, Amra; Pankiv, Serhiy; Bruserud, Oystein; Simonsen, Anne; Bjerkvig, Rolf; Bjørås, Magnar; Bøe, Stig Ove

    2012-07-26

    Arsenic in the form of arsenic trioxide (ATO) is used as a therapeutic drug for treatment of acute promyelocytic leukemia (APL). The mechanism by which this agent cures this disease was previously shown to involve direct interactions between ATO and the promyelocytic leukemia protein (PML), as well as accelerated degradation of the APL-associated fusion oncoprotein PML/retinoic acid receptor α (RARA). Here we investigated the fate of PML-generated nuclear structures called PML bodies in ATO-treated cells. We found that ATO inhibits formation of progeny PML bodies while it stabilizes cytoplasmic precursor compartments, referred to as cytoplasmic assemblies of PML and nucleoporins (CyPNs), after cell division. This block in PML body recycling is readily detected at pharmacologic relevant ATO concentrations (0.02-0.5μM) that do not cause detectable cell-cycle defects, and it does not require modification of PML by SUMOylation. In addition, PML and PML/RARA carrying mutations previously identified in ATO-resistant APL patients are impeded in their ability to become sequestered within CyPNs. Thus, ATO may inhibit nuclear activities of PML and PML/RARA in postmitotic cells through CyPN-dependent cytoplasmic sequestration.

  15. Tenuigenin exhibits protective effects against LPS-induced acute kidney injury via inhibiting TLR4/NF-κB signaling pathway.

    PubMed

    Fu, Haiyan; Hu, Zhansheng; Di, Xingwei; Zhang, Qiuhong; Zhou, Rongbin; Du, Hongyang

    2016-11-15

    Tenuigenin (TNG) has been reported to have various pharmacological activities, such as anti-oxidative and anti-inflammatory activities. However, the protective effects of TNG on lipopolysaccharides (LPS)-induced acute kidney injury (AKI) are still not clear. The aim of this study was to investigate the protective effects and mechanism of TGN on LPS-induced AKI in mice. The kidney histological change, levels of blood urea nitrogen (BUN), and creatinine were measured to assess the protective effects of TNG on LPS-induced AKI. The levels of TNF-α, IL-1β, and IL-6 in serum and kidney tissues were detected by ELISA. The extent of nuclear factor kappa-B (NF-κB) p65 and the expression of Toll-like receptor-4 (TLR4) were detected by western blot analysis. The results showed that TNG markedly attenuated the histological alterations, BUN and creatinine levels in kidney. TNG also suppressed LPS-induced TNF-α, IL-1β, and IL-6 production. Furthermore, the expression of TLR4 and NF-κB activation induced by LPS were markedly inhibited by TNG. In conclusion, this study demonstrated that TNG protected against LPS-induced AKI by inhibiting TLR4/NF-κB signaling pathway.

  16. Sodium orthovanadate associated with pharmacological doses of ascorbate causes an increased generation of ROS in tumor cells that inhibits proliferation and triggers apoptosis

    SciTech Connect

    Günther, T-hat nia Mara Fischer; Kviecinski, Maicon Roberto; Baron, Carla Cristine; Felipe, Karina Bettega; Farias, Mirelle Sifroni; Ourique da Silva, Fabiana; Bücker, Nádia Cristina Falcão; Pich, Claus Tröger; Ferreira, Eduardo Antonio; Filho, Danilo Wilhelm; Verrax, Julien; Calderon, Pedro Buc; Pedrosa, Rozangela Curi

    2013-01-18

    Graphical abstract: -- Abstract: Pharmacological doses of ascorbate were evaluated for its ability to potentiate the toxicity of sodium orthovanadate (Na{sub 3}VO{sub 4}) in tumor cells. Cytotoxicity, inhibition of cell proliferation, generation of ROS and DNA fragmentation were assessed in T24 cells. Na{sub 3}VO{sub 4} was cytotoxic against T24 cells (EC{sub 50} = 5.8 μM at 24 h), but in the presence of ascorbate (100 μM) the EC{sub 50} fell to 3.3 μM. Na{sub 3}VO{sub 4} plus ascorbate caused a strong inhibition of cell proliferation (up to 20%) and increased the generation of ROS (4-fold). Na{sub 3}VO{sub 4} did not directly cleave plasmid DNA, at this aspect no synergism was found occurring between Na{sub 3}VO{sub 4} and ascorbate once the resulting action of the combination was no greater than that of both substances administered separately. Cells from Ehrlich ascites carcinoma-bearing mice were used to determine the activity of antioxidant enzymes, the extent of the oxidative damage and the type of cell death. Na{sub 3}VO{sub 4} alone, or combined with ascorbate, increased catalase activity, but only Na{sub 3}VO{sub 4} plus ascorbate increased superoxide dismutase activity (up to 4-fold). Oxidative damage on proteins and lipids was higher due to the treatment done with Na{sub 3}VO{sub 4} plus ascorbate (2–3-fold). Ascorbate potentiated apoptosis in tumor cells from mice treated with Na{sub 3}VO{sub 4}. The results indicate that pharmacological doses of ascorbate enhance the generation of ROS induced by Na{sub 3}VO{sub 4} in tumor cells causing inhibition of proliferation and apoptosis. Apoptosis induced by orthovanadate and ascorbate is closer related to inhibition on Bcl-xL and activation of Bax. Our data apparently rule out a mechanism of cell demise p53-dependent or related to Cdk2 impairment.

  17. Pharmacological characterization of the metabotropic glutamate receptor inhibiting D-[3H]-aspartate output in rat striatum.

    PubMed Central

    Lombardi, G.; Alesiani, M.; Leonardi, P.; Cherici, G.; Pellicciari, R.; Moroni, F.

    1993-01-01

    1. The effects of several agonists of the metabotropic glutamate receptor (mGluR) were studied in adult rat striatal slices by measuring (i) KCl (30 mM)-induced output of previously taken up D-[3H]-aspartate (Asp), (ii) forskolin (30 microM)-induced adenosine 3':5'-cyclic monophosphate (cyclic AMP) accumulation and (iii) phophoinositide (PI) hydrolysis. 2. K(+)-induced efflux of D-[3H]-Asp was inhibited by the following mGluR agonists: (1S,3S,4S)-(carboxycyclopropyl)glycine (L-CCG-I), (1S,3R)-1-aminocyclopentane-1,3-dicarboxylic acid (1S,3R-ACPD) and quisqualic acid (Quis). 2-Amino-4-phosphonobutyrate (L-AP4) was inactive up to 300 microM. The maximal inhibition of D-[3H]-Asp output was 60 +/- 8%. The EC50s of mGluR agonists were: 0.5 microM for L-CCG-I, 100 microM for 1S,3R-ACPD and 100 microM for Quis. 3. Forskolin-induced cyclic AMP accumulation was also inhibited by mGluR agonists. The maximal inhibition was 50 +/- 4% and was obtained at a concentration of 10 microM for L-CCG-I and 100 microM for 1S,3R-ACPD. The EC50s for this inhibition were: 0.9 microM for L-CCG-I and 20 microM for 1S,3R-ACPD. Quis (300 microM) inhibited cyclic AMP accumulation by approximately 20%. L-AP4 slightly potentiated cyclic AMP accumulation. 4. PI hydrolysis was stimulated by mGluR agonists. The most potent compound was Quis (100 microM), which increased inositol phosphate formation up to 2.2 fold over control values. Its EC50 was 15 microM. L-CCG-I and 1S,3R-ACPD increased inositol phosphate formation by approximately 1.8 fold and their EC50 values were 30 and 25 microM, respectively. L-AP4 did not affect PI hydrolysis.(ABSTRACT TRUNCATED AT 250 WORDS) PMID:8306080

  18. Pharmacologic inhibition of MALT1 protease by phenothiazines as a therapeutic approach for the treatment of aggressive ABC-DLBCL.

    PubMed

    Nagel, Daniel; Spranger, Stefani; Vincendeau, Michelle; Grau, Michael; Raffegerst, Silke; Kloo, Bernhard; Hlahla, Daniela; Neuenschwander, Martin; Peter von Kries, Jens; Hadian, Kamyar; Dörken, Bernd; Lenz, Peter; Lenz, Georg; Schendel, Dolores J; Krappmann, Daniel

    2012-12-11

    Proteolytic activity of the mucosa-associated lymphoid tissue lymphoma translocation protein-1 (MALT1) paracaspase is required for survival of the activated B cell subtype of diffuse large B cell lymphoma (ABC-DLBCL). We have identified distinct derivatives of medicinal active phenothiazines, namely mepazine, thioridazine, and promazine, as small molecule inhibitors of the MALT1 protease. These phenothiazines selectively inhibit cleavage activity of recombinant and cellular MALT1 by a noncompetitive mechanism. Consequently, the compounds inhibit anti-apoptotic NF-κB signaling and elicit toxic effects selectively on MALT1-dependent ABC-DLBCL cells in vitro and in vivo. Our data provide a conceptual proof for a clinical application of distinct phenothiazines in the treatment of ABC-DLBCL.

  19. Genetic deletion and pharmacological inhibition of phosphodiesterase 10A protects mice from diet-induced obesity and insulin resistance.

    PubMed

    Nawrocki, Andrea R; Rodriguez, Carlos G; Toolan, Dawn M; Price, Olga; Henry, Melanie; Forrest, Gail; Szeto, Daphne; Keohane, Carol Ann; Pan, Yie; Smith, Karen M; Raheem, Izzat T; Cox, Christopher D; Hwa, Joyce; Renger, John J; Smith, Sean M

    2014-01-01

    Phosphodiesterase 10A (PDE10A) is a novel therapeutic target for the treatment of schizophrenia. Here we report a novel role of PDE10A in the regulation of caloric intake and energy homeostasis. PDE10A-deficient mice are resistant to diet-induced obesity (DIO) and associated metabolic disturbances. Inhibition of weight gain is due to hypophagia after mice are fed a highly palatable diet rich in fats and sugar but not a standard diet. PDE10A deficiency produces a decrease in caloric intake without affecting meal frequency, daytime versus nighttime feeding behavior, or locomotor activity. We tested THPP-6, a small molecule PDE10A inhibitor, in DIO mice. THPP-6 treatment resulted in decreased food intake, body weight loss, and reduced adiposity at doses that produced antipsychotic efficacy in behavioral models. We show that PDE10A inhibition increased whole-body energy expenditure in DIO mice fed a Western-style diet, achieving weight loss and reducing adiposity beyond the extent seen with food restriction alone. Therefore, chronic THPP-6 treatment conferred improved insulin sensitivity and reversed hyperinsulinemia. These data demonstrate that PDE10A inhibition represents a novel antipsychotic target that may have additional metabolic benefits over current medications for schizophrenia by suppressing food intake, alleviating weight gain, and reducing the risk for the development of diabetes.

  20. Pharmacological inhibitions of glutamate transporters EAAT1 and EAAT2 compromise glutamate transport in photoreceptor to ON- bipolar cell synapses

    PubMed Central

    Tse, Dennis Y.; Chung, Inyoung; Wu, Samuel M.

    2015-01-01

    To maintain reliable signal transmission across a synapse, free synaptic neurotransmitters must be removed from the cleft in a timely manner. In the first visual synapse, this critical task is mainly undertaken by glutamate transporters (EAATs). Here we study the differential roles of the EAAT1, EAAT2 and EAAT5 subtypes in glutamate (GLU) uptake at the photoreceptor-to-depolarizing bipolar cell synapse in intact dark-adapted retina. Various doses of EAAT blockers and/or GLU were injected into the eye before the electroretinogram (ERG) was measured. Their effectiveness and potency in inhibiting the ERG b-wave were studied to determine their relative contributions to the GLU clearing activity at the synapse. The results showed that EAAT1 and EAAT2 plays different roles. Selectively blocking glial EAAT1 alone using UCPH101 inhibited the b-wave 2–24 hours following injection, suggesting a dominating role of EAAT1 in the overall GLU clearing capacity in the synaptic cleft. Selectively blocking EAAT2 on photoreceptor terminals had no significant effect on the b-wave, but increased the potency of exogenous GLU in inhibiting the b-wave. These suggest that EAAT2 play a secondary yet significant role in the GLU reuptake activity at the rod and the cone output synapses. Additionally, we have verified our electrophysiological findings with double-label immunohistochemistry, and extend the literature on the spatial distribution of EAAT2 splice variants in the mouse retina. PMID:25152321

  1. Melatonin alleviates acute lung injury through inhibiting the NLRP3 inflammasome.

    PubMed

    Zhang, Yong; Li, Xiru; Grailer, Jamison J; Wang, Na; Wang, Mingming; Yao, Jianfei; Zhong, Rui; Gao, George F; Ward, Peter A; Tan, Dun-Xian; Li, Xiangdong

    2016-05-01

    Acute lung injury (ALI) and acute respiratory distress syndrome (ARDS) are clinically severe respiratory disorders, and there are currently no Food and Drug Administration-approved drug therapies. Melatonin is a well-known anti-inflammatory molecule, which has proven to be effective in ALI induced by many conditions. Emerging studies suggest that the NLRP3 inflammasome plays a critical role during ALI. How melatonin directly blocks activation of the NLRP3 inflammasome in ALI remains unclear. In this study, using an LPS-induced ALI mouse model, we found intratracheal (i.t.) administration of melatonin markedly reduced the pulmonary injury and decreased the infiltration of macrophages and neutrophils into lung. During ALI, the NLRP3 inflammasome is significantly activated with a large amount of IL-1β and the activated caspase-1 occurring in the lung. Melatonin inhibits the activation of the NLRP3 inflammasome by both suppressing the release of extracellular histones and directly blocking histone-induced NLRP3 inflammasome activation. Notably, i.t. route of melatonin administration opens a more efficient therapeutic approach for treating ALI.

  2. Inhibiting glycogen synthase kinase-3 mitigates the hematopoietic acute radiation syndrome in mice.

    PubMed

    Lee, Chang-Lung; Lento, William E; Castle, Katherine D; Chao, Nelson J; Kirsch, David G

    2014-05-01

    Exposure to a nuclear accident or radiological attack can cause death from acute radiation syndrome (ARS), which results from radiation injury to vital organs such as the hematopoietic system. However, the U.S. Food and Drug Administration (FDA) has not approved any medical countermeasures for this specific purpose. With growing concern over nuclear terrorism, there is an urgent need to develop small molecule deliverables that mitigate mortality from ARS. One emerging modulator of hematopoietic stem/progenitor cell (HSPC) activity is glycogen synthase kinase-3 (GSK-3). The inhibition of GSK-3 has been shown to augment hematopoietic repopulation in mouse models of bone marrow transplantation. In this study, we performed an in vitro screen using irradiated bone marrow mononuclear cells (BM-MNCs) to test the effects of four GSK-3 inhibitors: CHIR99021; 6-Bromoindirubin-3'-oxime (BIO); SB415286; and SB216763. This screen showed that SB216763 significantly increased the frequency of c-Kit(+) Lin(-) Sca1(+) (KLS) cells and hematopoietic colony-forming cells in irradiated BM-MNCs. Importantly, administration of a single dose of SB216763 to C57BL/6J mice by subcutaneous injection 24 h after total-body irradiation significantly improved hematopoietic recovery and mitigated hematopoietic ARS. Collectively, our results demonstrate that the GSK-3 inhibitor SB216763 is an effective medical countermeasure against acute radiation injury of the hematopoietic system.

  3. Inhibiting Glycogen Synthase Kinase-3 Mitigates the Hematopoietic Acute Radiation Syndrome in Mice

    PubMed Central

    Lee, Chang-Lung; Lento, William E.; Castle, Katherine D.; Chao, Nelson J.; Kirsch, David G.

    2014-01-01

    Exposure to a nuclear accident or radiological attack can cause death from acute radiation syndrome (ARS), which results from radiation injury to vital organs such as the hematopoietic system. However, the U.S. Food and Drug Administration (FDA) has not approved any medical countermeasures for this specific purpose. With growing concern over nuclear terrorism, there is an urgent need to develop small molecule deliverables that mitigate mortality from ARS. One emerging modulator of hematopoietic stem/progenitor cell (HSPC) activity is glycogen synthase kinase-3 (GSK-3). The inhibition of GSK-3 has been shown to augment hematopoietic repopulation in mouse models of bone marrow transplantation. In this study, we performed an in vitro screen using irradiated bone marrow mononuclear cells (BM-MNCs) to test the effects of four GSK-3 inhibitors: CHIR99021; 6-Bromoindirubin-3′-oxime (BIO); SB415286; and SB216763. This screen showed that SB216763 significantly increased the frequency of c-Kit+ Lin− Sca1+ (KLS) cells and hematopoietic colony-forming cells in irradiated BM-MNCs. Importantly, administration of a single dose of SB216763 to C57BL/6J mice by subcutaneous injection 24 h after total-body irradiation significantly improved hematopoietic recovery and mitigated hematopoietic ARS. Collectively, our results demonstrate that the GSK-3 inhibitor SB216763 is an effective medical countermeasure against acute radiation injury of the hematopoietic system. PMID:24720754

  4. Kynurenine–3–monooxygenase inhibition prevents multiple organ failure in rodent models of acute pancreatitis

    PubMed Central

    Mole, Damian J; Webster, Scott P; Uings, Iain; Zheng, Xiaozhong; Binnie, Margaret; Wilson, Kris; Hutchinson, Jonathan P; Mirguet, Olivier; Walker, Ann; Beaufils, Benjamin; Ancellin, Nicolas; Trottet, Lionel; Bénéton, Véronique; Mowat, Christopher G; Wilkinson, Martin; Rowland, Paul; Haslam, Carl; McBride, Andrew; Homer, Natalie ZM; Baily, James E; Sharp, Matthew GF; Garden, O James; Hughes, Jeremy; Howie, Sarah EM; Holmes, Duncan S; Liddle, John; Iredale, John P

    2015-01-01

    Acute pancreatitis (AP) is a common and devastating inflammatory condition of the pancreas that is considered to be a paradigm of sterile inflammation leading to systemic multiple organ dysfunction syndrome (MODS) and death1,2 Acute mortality from AP-MODS exceeds 20%3 and for those who survive the initial episode, their lifespan is typically shorter than the general population4. There are no specific therapies available that protect individuals against AP-MODS. Here, we show that kynurenine-3-monooxygenase (KMO), a key enzyme of tryptophan metabolism5, is central to the pathogenesis of AP-MODS. We created a mouse strain deficient for Kmo with a robust biochemical phenotype that protected against extrapancreatic tissue injury to lung, kidney and liver in experimental AP-MODS. A medicinal chemistry strategy based on modifications of the kynurenine substrate led to the discovery of GSK180 as a potent and specific inhibitor of KMO. The binding mode of the inhibitor in the active site was confirmed by X-ray co-crystallography at 3.2 Å resolution. Treatment with GSK180 resulted in rapid changes in levels of kynurenine pathway metabolites in vivo and afforded therapeutic protection against AP-MODS in a rat model of AP. Our findings establish KMO inhibition as a novel therapeutic strategy in the treatment of AP-MODS and open up a new area for drug discovery in critical illness. PMID:26752518

  5. Subchronic and acute preclinic toxicity and some pharmacological effects of the water extract from leaves of Petiveria alliacea (Phytolaccaceae).

    PubMed

    García-González, Mildred; Morales, Teresita Coto; Ocampo, Rafael; Pazos, Liliana

    2006-12-01

    We tested the effects of the aqueous extract of Petiveria alliacea leaves on acute and sub-chronic toxicity, hematocrit and blood glucose level and intestinal motility of male albino NGP mice of 20 to 25 g mean weight. Treatments were in all cases doses of 1,000 and 2,000 mg/kg animal weight and a control treatment with 0.5 ml distilled water, using 10 animals per treatment and administered orally every day (5 days per week). Experimental periods were 18 and 70 days for acute and sub chronic toxicity, respectively. No mortality nor any toxicity signs could be observed. A slight but significant increase in the glucose levels during the first three weeks was observed with the 1,000 mg/kg dose but not for the higher 2,000 mg/kg dose. After administering the doses once after a starving period of six hours, no significant differences in intestinal motility could be found.

  6. Pharmacological Evaluation of Antidepressant-Like Effect of Genistein and Its Combination with Amitriptyline: An Acute and Chronic Study

    PubMed Central

    Gupta, Gaurav; Jia Jia, Tay; Yee Woon, Lim; Kumar Chellappan, Dinesh; Candasamy, Mayuren; Dua, Kamal

    2015-01-01

    The present study was designed to evaluate the acute and chronic antidepressant effect of genistein in combination with amitriptyline in mice. Animals were divided into six groups (n = 6) for treatment with water, genistein, or amitriptyline, either alone or in combination for ten days. Animals were subjected to locomotor activity testing; tail suspension test (TST); and forced swim test (FST) and immobility time was recorded on day one and day ten. Acute treatment of all treatment groups did not significantly reduce the immobility time (p > 0.05). Chronic treatment of combination of genistein (10 mg/kg) and amitriptyline (5 mg/kg and 10 mg/kg) significantly reduced the immobility time as compared to control group (p < 0.001) and was comparable to amitriptyline alone (10 mg/kg). However, no changes in anti-immobility activity in combination of subeffective doses of genistein (5 mg/kg) and amitriptyline (5 mg/kg) were observed. Genistein at its standard dose (10 mg/kg) rendered synergistic effects in combination with subeffective dose of amitriptyline (5 mg/kg) and additive effects in combination with therapeutic dose of amitriptyline (10 mg/kg). PMID:26681936

  7. Pharmacologic analysis of inhibition produced by last-order intermediate nucleus interneurons mediating nonreciprocal inhibition of motoneurons in cat spinal cord.

    PubMed

    Rudomin, P; Jiménez, I; Quevedo, J; Solodkin, M

    1990-01-01

    1. The aim of this study was to investigate the effects of drugs blocking glycinergic and GABAergic transmission on the postsynaptic inhibition of hindlimb motoneurons produced by activation of last-order laminae V-VI interneurons, which are coexcited by muscle and cutaneous afferents and have axonal branches projecting to the Clarke's column. 2. In anesthetized cats with right spinal cord hemisected and both dorsal columns cut between L4 and L5 segments, stimulation of the Clarke's column (CC) at L3-L4 level produced a short-latency, presumably monosynaptic, inhibitory potential that could be recorded either from L7 or S1 ventral rootlets by means of the sucrose-gap technique (iVRP) or intracellularly from hindlimb motoneurons (IPSP). These potentials have been attributed to antidromic activation of a population of last-order interneurons mediating nonreciprocal inhibition of motoneurons. 3. The early iVRP and IPSP produced by CC stimulation was practically abolished 10-20 s after the intravenous injection of strychnine (0.1 mg/kg) and replaced by an excitatory synaptic potential followed by delayed, slow, strychnine-resistant inhibitory potential. 4. Monosynaptic reflexes (MSR) elicited by stimulation of group I gastrocnemius (GS) afferents were inhibited during the occurrence of the CC-iVRP. This inhibition was significantly reduced after intravenous strychnine. On the other hand, the inhibition of the GS-MSR, produced by conditioning stimulation of the posterior biceps and semitendinosus (PBSt) nerve with trains of pulses applied 25-35 ms before the test stimulus, was practically unchanged after the intravenous injection of strychnine. 5. The CC-iVRP and the associated inhibition of GS-MSRs were not significantly affected after the intravenous injection of 0.1 mg/kg of picrotoxin, which clearly reduced the dorsal root potentials (DRP), the late component of the iVRP, and the inhibition of MSRs produced by PBSt volleys. 6. The effect of strychnine and picrotoxin

  8. FLT3 inhibition: a moving and evolving target in acute myeloid leukaemia.

    PubMed

    Leung, A Y H; Man, C-H; Kwong, Y-L

    2013-02-01

    Internal tandem duplication (ITD) of the fms-like tyrosine kinase 3 (FLT3) gene is a gain-of-function mutation common in acute myeloid leukaemia (AML). It is associated with inferior prognosis and response to chemotherapy. Single base mutations at the FLT3 tyrosine kinase domain (TKD) also leads to a gain of function, although its prognostic significance is less well defined because of its rarity. The clinical benefits of FLT3 inhibition are generally limited to AML with FLT3-ITD. However, responses are transient and leukaemia progression invariably occurs. There is compelling evidence that leukaemia clones carrying both ITD and TKD mutations appear when resistance to FLT3 inhibitors occurs. Interestingly, the emergence of double ITD and TKD mutants can be recapitulated in vitro when FLT3-ITD+ leukaemia cell lines are treated with mutagens and FLT3 inhibitors. Furthermore, murine xenotransplantation models also suggest that, in some cases, the FTL3-ITD and TKD double mutants actually exist in minute amounts before treatment with FLT3 inhibitors, expand under the selection pressure of FLT3 inhibition and become the predominant resistant clone(s) during the drug-refractory phase. On the basis of this model of clonal evolution, a multipronged strategy using more potent FLT3 inhibitors, and a combinatorial approach targeting both FLT3-dependent and FLT3-independent pathways, will be needed to improve outcome.

  9. Inhibition of NEDD8-activating enzyme: a novel approach for the treatment of acute myeloid leukemia.

    PubMed

    Swords, Ronan T; Kelly, Kevin R; Smith, Peter G; Garnsey, James J; Mahalingam, Devalingam; Medina, Ernest; Oberheu, Kelli; Padmanabhan, Swaminathan; O'Dwyer, Michael; Nawrocki, Steffan T; Giles, Francis J; Carew, Jennifer S

    2010-05-06

    NEDD8 activating enzyme (NAE) has been identified as an essential regulator of the NEDD8 conjugation pathway, which controls the degradation of many proteins with important roles in cell-cycle progression, DNA damage, and stress responses. Here we report that MLN4924, a novel inhibitor of NAE, has potent activity in acute myeloid leukemia (AML) models. MLN4924 induced cell death in AML cell lines and primary patient specimens independent of Fms-like tyrosine kinase 3 expression and stromal-mediated survival signaling and led to the stabilization of key NAE targets, inhibition of nuclear factor-kappaB activity, DNA damage, and reactive oxygen species generation. Disruption of cellular redox status was shown to be a key event in MLN4924-induced apoptosis. Administration of MLN4924 to mice bearing AML xenografts led to stable disease regression and inhibition of NEDDylated cullins. Our findings indicate that MLN4924 is a highly promising novel agent that has advanced into clinical trials for the treatment of AML.

  10. Wnt inhibition leads to improved chemosensitivity in paediatric acute lymphoblastic leukaemia.

    PubMed

    Dandekar, Smita; Romanos-Sirakis, Eleny; Pais, Faye; Bhatla, Teena; Jones, Courtney; Bourgeois, Wallace; Hunger, Stephen P; Raetz, Elizabeth A; Hermiston, Michelle L; Dasgupta, Ramanuj; Morrison, Debra J; Carroll, William L

    2014-10-01

    While childhood acute lymphoblastic leukaemia (ALL) is now highly curable, the dismal prognosis for children who relapse warrants novel therapeutic approaches. Previously, using an integrated genomic analysis of matched diagnosis-relapse paired samples, we identified overactivation of the Wnt pathway as a possible mechanism of recurrence. To validate these findings and document whether Wnt inhibition may sensitize cells to chemotherapy, we analysed the expression of activated β-catenin (and its downstream target BIRC5) using multiparameter phosphoflow cytometry and tested the efficacy of a recently developed Wnt inhibitor, iCRT14, in ALL cell lines and patient samples. We observed increased activation of β-catenin at relapse in 6/10 patients. Furthermore, treatment of leukaemic cell lines with iCRT14 led to significant downregulation of Wnt target genes and combination with traditional chemotherapeutic drugs resulted in a synergistic decrease in viability as well as a significant increase in apoptotic cell death. Finally, pre-treatment of purified blasts from patients with relapsed leukaemia with the Wnt inhibitor followed by exposure to prednisolone, restored chemosensitivity in these cells. Our results demonstrate that overactivation of the Wnt pathway may contribute to chemoresistance in relapsed childhood ALL and that Wnt-inhibition may be a promising therapeutic approach.

  11. Calpain Inhibition Attenuates Apoptosis of Retinal Ganglion Cells in Acute Optic Neuritis

    PubMed Central

    Smith, Amena W.; Das, Arabinda; Guyton, M. Kelly; Ray, Swapan K.; Rohrer, Baerbel

    2011-01-01

    Purpose. Optic neuritis (ON), inflammation of the optic nerve, is strongly associated with the pathogenesis of multiple sclerosis (MS) and is initiated by the attack of autoreactive T cells against self-myelin antigens, resulting in demyelination, degeneration of retinal ganglion cells (RGCs), and cumulative visual impairment. Methods. Experimental autoimmune encephalomyelitis (EAE) was induced in Lewis rats on day 0, and animals received daily intraperitoneal injections of calpain inhibitor (calpeptin) or vehicle from day 1 until killed. Retinal cell death was analyzed by DNA fragmentation, and surviving ganglion cells were quantified after double labeling of retinal tissue with TUNEL and Brn3a. The expression of apoptotic and inflammatory proteins was determined by Western blotting. Results. It was demonstrated that calpain inhibition downregulates expression of proapoptotic proteins and the proinflammatory molecule nuclear factor-kappa B (NF-κB) in the retina of Lewis rats with acute EAE. Immunofluorescent labeling revealed that apoptotic cells in the RGC layer of vehicle-treated EAE animals were Brn3a positive, and a moderate dose of calpeptin dramatically reduced the frequency of apoptotic RGCs. Conclusions. These results suggest that calpain inhibition might be a useful supplement to immunomodulatory therapies such as corticosteroids in ON, due to its neuroprotective effect on RGCs. PMID:21613375

  12. Astragaloside IV ameliorates acute pancreatitis in rats by inhibiting the activation of nuclear factor-κB

    PubMed Central

    QIU, LEI; YIN, GUOJIAN; CHENG, LI; FAN, YUTING; XIAO, WENQIN; YU, GE; XING, MIAO; JIA, RONGRONG; SUN, RUIQING; MA, XIUYING; HU, GUOYONG; WANG, XINGPENG; TANG, MAOCHUN; ZHAO, YAN

    2015-01-01

    This study aimed to investigate the effects of astragaloside IV (AS-IV; 3-O-β-D-xylopyranosyl-6-O-β-D-glucopyranosylcycloastragenol), which has been reported to have comprehensive pharmacological functions, on sodium taurocholate (NaTc)/L-arginine (L-Arg)-induced acute pancreatitis (AP) in rats in vivo and in rat pancreatic acinar cells in vitro. NaTc-induced experimental AP was induced in rats by injecting 4% NaTc (0.1 ml/100 g) in the retrograde direction of the biliopancreatic duct. L-Arg-induced experimental AP was induced in rats by 2 intraperitoneal injections of 20% L-arg (3 g/kg), with an interval of 1 h between the injections. The rats were pre-treated AS-IV (50 mg/kg) or the vehicle (DMSO) 2 h prior to the induction of AP. Enzyme-linked immunosorbent assay, H&E staining, myeloperoxidase (MPO) activity, reverse transcription-quantitative PCR, western blot analysis and immunohistochemistry were used to evaluate the effects of AS-IV on AP. The results revealed that treatment with AS-IV significantly reduced serum amylase and lipase levels, pancreatic pathological alterations, the secretion of pro-inflammatory cytokines, MPO activity, and the protein expression of nuclear factor-κB (NF-κB) in vivo. Moreover, pre-treatment with AS-IV significantly increased the expression levels of manganese superoxide dismutase and cuprum/zinc superoxide dismutase. In the in vitro experiment, treatment of the cells with AS-IV aslo reduced rat pancreatic acinar cell necrosis and nuclear NF-κB activity, and enhanced the protein expression of superoxide dismutase. In conclusion, this study indicates that the protective effects of AS-IV on experimental AP in rats may be closely related to the inhibition of NF-κB. In addition, our results indicate that AS-IV may exert potential antioxidant effects on AP. Therefore, AS-IV may be an effective therapeutic agent for AP. PMID:25604657

  13. Phase I and Pharmacologic Trial of Cytosine Arabinoside with the Selective Checkpoint 1 Inhibitor Sch 900776 in Refractory Acute Leukemias

    PubMed Central

    Karp, Judith E.; Thomas, Brian M.; Greer, Jacqueline M.; Sorge, Christopher; Gore, Steven D.; Pratz, Keith W.; Smith, B. Douglas; Flatten, Karen S.; Peterson, Kevin; Schneider, Paula; Mackey, Karen; Freshwater, Tomoko; Levis, Mark J.; McDevitt, Michael A.; Carraway, Hetty E.; Gladstone, Douglas E.; Showel, Margaret M.; Loechner, Sabine; Parry, David A.; Horowitz, Jo Ann; Isaacs, Randi; Kaufmann, Scott H.

    2013-01-01

    Purpose Incorporation of cytarabine into DNA activates checkpoint kinase 1 (Chk1), which stabilizes stalled replication forks, induces S-phase slowing, and diminishes cytarabine cytotoxicity. The selective Chk1 inhibitor SCH 900776 abrogates cytarabine-induced S-phase arrest and enhances cytarabine cytotoxicity in acute leukemia cell lines and leukemic blasts in vitro. To extend these findings to the clinical setting, we have conducted a phase I study of cytarabine and SCH 900776. Experimental Design Twenty-four adults with relapsed and refractory acute leukemias received timed sequential, continuous infusion cytarabine 2 g/m2 over 72 hours (667 mg/m2/24 hours) beginning on day 1 and again on day 10. SCH 900776 was administered as a 15- to 30-minute infusion on days 2, 3, 11, and 12. The starting dose of SCH 900776 was 10 mg/m2/dose. Results Dose-limiting toxicities consisting of corrected QT interval prolongation and grade 3 palmar-plantar erythrodysesthesia occurred at 140 mg flat dosing (dose level 5, equivalent to 80 mg/m2). Complete remissions occurred in 8 of 24 (33%) patients, with 7 of 8 at 40 mg/m2 or higher. SCH 900776 did not accumulate at any dose level. Marrow blasts obtained pretreatment and during therapy showed increased phosphorylation of H2Ax after SCH 900776 beginning at 40 mg/m2, consistent with unrepaired DNA damage. Conclusions These data support a randomized phase II trial of cytarabine +/− SCH 900776 at a recommended flat dose of 100 mg (equivalent to 56 mg/m2) for adults with poor-risk leukemias. The trial (SP P05247) was registered at www.clinicaltrials.gov as NCT #00907517. PMID:23092873

  14. P2X7 receptor inhibition protects against ischemic acute kidney injury in mice.

    PubMed

    Yan, Yanli; Bai, Jianwen; Zhou, Xiaoxu; Tang, Jinhua; Jiang, Chunming; Tolbert, Evelyn; Bayliss, George; Gong, Rujun; Zhao, Ting C; Zhuang, Shougang

    2015-03-15

    Activation of the purinergic P2X7 receptor (P2X7R) has been associated with the development of experimental nephritis and diabetic and hypertensive nephropathy. However, its role in acute kidney injury (AKI) remains unknown. In this study, we examined the effects of P2X7R inhibition in a murine model of ischemia-reperfusion (I/R)-induced AKI using A438079, a selective inhibitor of P2X7R. At 24 h after I/R, mice developed renal dysfunction and renal tubular damage, which was accompanied by elevated expression of P2X7R. Early administration of A438079 immediately or 6 h after the onset of reperfusion protected against renal dysfunction and attenuated kidney damage whereas delayed administration of A438079 at 24 h after restoration of perfusion had no protective effects. The protective actions of A438079 were associated with inhibition of renal tubule injury and cell death and suppression of renal expression of monocyte chemotactic protein-1 and regulated upon expression normal T cell expressed and secreted (RANTES). Moreover, I/R injury led to an increase in phosphorylation (activation) of extracellular signal-regulated kinases 1/2 in the kidney; treatment with A438079 diminished this response. Collectively, these results indicate that early P2X7R inhibition is effective against renal tubule injury and proinflammatory response after I/R injury and suggest that targeting P2X7R may be a promising therapeutic strategy for treatment of AKI.

  15. Administration of deoxyribonucleosides or inhibition of their catabolism as a pharmacological approach for mitochondrial DNA depletion syndrome.

    PubMed

    Cámara, Yolanda; González-Vioque, Emiliano; Scarpelli, Mauro; Torres-Torronteras, Javier; Caballero, Andrea; Hirano, Michio; Martí, Ramon

    2014-05-01

    Mitochondrial DNA (mtDNA) depletion syndrome (MDS) is characterized by a reduction in mtDNA copy number and consequent mitochondrial dysfunction in affected tissues. A subgroup of MDS is caused by mutations in genes that disrupt deoxyribonucleotide metabolism, which ultimately leads to limited availability of one or several deoxyribonucleoside triphosphates (dNTPs), and subsequent mtDNA depletion. Here, using in vitro experimental approaches (primary cell culture of deoxyguanosine kinase-deficient cells and thymidine-induced mtDNA depletion in culture as a model of mitochondrial neurogastrointestinal encephalomyopathy, MNGIE), we show that supplements of those deoxyribonucleosides (dNs) involved in each biochemical defect (deoxyguanosine or deoxycytidine, dCtd) prevents mtDNA copy number reduction. Similar effects can be obtained by specific inhibition of dN catabolism using tetrahydrouridine (THU; inhibitor of cytidine deaminase) or immucillin H (inhibitor of purine nucleoside phosphorylase). In addition, using an MNGIE animal model, we provide evidence that mitochondrial dNTP content can be modulated in vivo by systemic administration of dCtd or THU. In spite of the severity associated with diseases due to defects in mtDNA replication, there are currently no effective therapeutic options available. Only in the case of MNGIE, allogeneic hematopoietic stem cell transplantation has proven efficient as a long-term therapeutic strategy. We propose increasing cellular availability of the deficient dNTP precursor by direct administration of the dN or inhibition of its catabolism, as a potential treatment for mtDNA depletion syndrome caused by defects in dNTP metabolism.

  16. Pharmacological Inhibition of PERK Attenuates Early Brain Injury After Subarachnoid Hemorrhage in Rats Through the Activation of Akt.

    PubMed

    Yan, Feng; Cao, Shenglong; Li, Jianru; Dixon, Brandon; Yu, Xiaobo; Chen, Jingyin; Gu, Chi; Lin, Wang; Chen, Gao

    2017-04-01

    Neuronal apoptosis is a central pathological process in subarachnoid hemorrhage (SAH)-induced early brain injury. Endoplasmic reticulum (ER) stress was reported to have a vital role in the pathophysiology of neuronal apoptosis in the brain. The present study was designed to investigate the potential effects of ER stress and its downstream signals in early brain injury after SAH. One hundred thirty-four rats were subjected to an endovascular perforation model of SAH. The RNA-activated protein kinase-like ER kinase (PERK) inhibitor GSK2606414 and the Akt inhibitor MK2206 were injected intracerebroventricularly. SAH grade, neurologic scores, and brain water content were measured 72 h after subarachnoid hemorrhage. Expression of PERK and its downstream signals, Akt, Bcl-2, Bax, and cleaved caspase-3, were examined using Western blot analysis. Specific cell types that expressed PERK were detected with double immunofluorescence staining. Neuronal cell death was demonstrated with terminal deoxynucleotidyl transferase (TdT)-mediated dUTP nick end labeling (TUNEL). Our results showed that the expression of p-PERK and its downstream targets, p-eIF2α and ATF4, increased after SAH and peaked at 72 h after SAH. PERK was expressed mostly in neurons. The inhibition of PERK with GSK2606414 reduced p-PERK, p-eIF2α, and ATF4 expression. Furthermore, GSK2606414 treatment increased p-Akt levels and the Bcl-2/Bax ratio as well as decreased cleaved caspase-3 expression and neuronal death, thereby improving neurological deficits at 72 h after SAH. The selective Akt inhibitor MK2206 abolished the beneficial effects of GSK2606414. PERK, the major transducer of ER stress, is involved in neuronal apoptosis after SAH. The inhibition of PERK reduces early brain injury via Akt-related anti-apoptosis pathways. PERK may serve as a promising target for future therapeutic intervention.

  17. Pharmacological evidence that spinal α(2C)- and, to a lesser extent, α(2A)-adrenoceptors inhibit capsaicin-induced vasodilatation in the canine external carotid circulation.

    PubMed

    Villalón, Carlos M; Galicia-Carreón, Jorge; González-Hernández, Abimael; Marichal-Cancino, Bruno A; Manrique-Maldonado, Guadalupe; Centurión, David

    2012-05-15

    During a migraine attack capsaicin-sensitive trigeminal sensory nerves release calcitonin gene-related peptide (CGRP), producing cranial vasodilatation and central nociception; hence, trigeminal inhibition may prevent this vasodilatation and abort migraine headache. This study investigated the role of spinal α₂-adrenoceptors and their subtypes (i.e. α(2A), α(2B) and/or α(2C)-adrenoceptors) in the inhibition of the canine external carotid vasodilator responses to capsaicin. Anaesthetized vagosympathectomized dogs were prepared to measure arterial blood pressure, heart rate and external carotid conductance. The thyroid artery was cannulated for one-min intracarotid infusions of capsaicin, α-CGRP and acetylcholine. A cannula was inserted intrathecally for spinal (C₁-C₃) administration of 2-amino-6-ethyl-4,5,7,8-tetrahydro-6H-oxazolo-[5,4-d]-azepin-dihydrochloride (B-HT 933; a selective α₂-adrenoceptor agonist) and/or the α₂-adrenoceptor antagonists rauwolscine (α(2A/2B/2C)), 2-[(4,5-dihydro-1H-imidazol-2-yl)methyl]-2,3-dihydro-1-methyl-1H-isoindole maleate (BRL44408; α(2A)), imiloxan (α(2B)) or acridin-9-yl-[4-(4-methylpiperazin-1-yl)-phenyl]amine (JP-1302; α(2C)). Infusions of capsaicin, α-CGRP and acetylcholine dose-dependently increased the external carotid conductance. Intrathecal B-HT 933 (1000 and 3100 μg) inhibited the vasodilator responses to capsaicin, but not those to α-CGRP or acetylcholine. This inhibition, abolished by rauwolscine (310 μg), was: (i) unaffected by 3,100 μg imiloxan; (ii) partially blocked by 310 μg of BRL44408 or 100 μg of JP-1302; and (iii) abolished by 1,000 μg of BRL44408 or 310 μg of JP-1302. Thus, intrathecal B-HT 933 inhibited the external carotid vasodilator responses to capsaicin. This response, mediated by spinal α₂-adrenoceptors unrelated to the α(2B)-adrenoceptor subtype, resembles the pharmacological profile of α(2C)-adrenoceptors and, to a lesser extent, α(2A)-adrenoceptors.

  18. [Liver rupture of a subcapsular haematoma after pharmacologic revascularization (Streptokinase) for acute myocardial infarction--case report].

    PubMed

    Tomescu, Dana; Vişan, Anca; Popescu, I; Tulbure, D

    2008-01-01

    We report the case of a 56 years old male patient, smoker, obese, with untreated arterial hypertension, hospitalized on 16.02.07 with the diagnosis of inferior acute myocardial infarction, for which he received thrombolysis with streptokinase, followed by anticoagulation with non fractioned heparin. Two days later he started to complain of acute abdominal pain, and laboratory findings showed a low hemoglobin level. Imaging findings (ultrasonography and CT scan) showed evidence of subcapsular liver haematoma, caused by bleeding at hepatic and splenic level. He received red blood packed cells, fresh frozen plasma, cryoprecipitate, activated factor VII and was transferred by helicopter to Fundeni Clinical Institute--Intensive care unit (ICU). On admission, the patient was conscious, anxious, dyspneic, with mild hypoxia, with no signs of low cardiac output and with a painful abdomen. ECG, echocardiography and elevated myocardial necrosis enzymes confirmed myocardial infarction. Shortly after admission there was a worsening of his clinical condition, with a decrease in hemoglobin level despite red blood packed cells administration (Hb=7.8 g/dl) and thrombocytopenia (82000/mmc), with normal coagulation tests, thus suggesting active intraabdominal bleeding. Echography and CT scan confirmed bleeding. Emergency surgery was performed, showing massive haemoperitoneum (approx 4.5 L of blood), due to spontaneous rupture of a subcapsular hematoma in the liver. The surgical hemostasis was performed on the liver parenchyma laceration. Duration of surgery was 4 hours. There were no significant cardiac events during surgery (no signs of ischemia on ECG, no ST elevation), despite the need for inotropic agent. After surgery, the patient was referred to the ICU, intubated and ventilated, with inotropic support - dobutamine. Sequential ECG's, enzymatic trend and echocardiographies were performed to monitor myocardial ischemia. The outcome was favourable, no further bleeding and no

  19. Pharmacological targeting of miR-155 via the NEDD8-activating enzyme inhibitor MLN4924 (Pevonedistat) in FLT3-ITD acute myeloid leukemia.

    PubMed

    Khalife, J; Radomska, H S; Santhanam, R; Huang, X; Neviani, P; Saultz, J; Wang, H; Wu, Y-Z; Alachkar, H; Anghelina, M; Dorrance, A; Curfman, J; Bloomfield, C D; Medeiros, B C; Perrotti, D; Lee, L J; Lee, R J; Caligiuri, M A; Pichiorri, F; Croce, C M; Garzon, R; Guzman, M L; Mendler, J H; Marcucci, G

    2015-10-01

    High levels of microRNA-155 (miR-155) are associated with poor outcome in acute myeloid leukemia (AML). In AML, miR-155 is regulated by NF-κB, the activity of which is, in part, controlled by the NEDD8-dependent ubiquitin ligases. We demonstrate that MLN4924, an inhibitor of NEDD8-activating enzyme presently being evaluated in clinical trials, decreases binding of NF-κB to the miR-155 promoter and downregulates miR-155 in AML cells. This results in the upregulation of the miR-155 targets SHIP1, an inhibitor of the PI3K/Akt pathway, and PU.1, a transcription factor important for myeloid differentiation, leading to monocytic differentiation and apoptosis. Consistent with these results, overexpression of miR-155 diminishes MLN4924-induced antileukemic effects. In vivo, MLN4924 reduces miR-155 expression and prolongs the survival of mice engrafted with leukemic cells. Our study demonstrates the potential of miR-155 as a novel therapeutic target in AML via pharmacologic interference with NF-κB-dependent regulatory mechanisms. We show the targeting of this oncogenic microRNA with MLN4924, a compound presently being evaluated in clinical trials in AML. As high miR-155 levels have been consistently associated with aggressive clinical phenotypes, our work opens new avenues for microRNA-targeting therapeutic approaches to leukemia and cancer patients.

  20. The pharmacologic basis for the efficacy of high-dose Ara-C and sequential asparaginase in adult acute myelogenous leukemia.

    PubMed Central

    Capizzi, R. L.; White, C.

    1988-01-01

    Dose-related effects of ara-C include overcoming a relative transport impediment in human leukemia cells. This result then allows intracellular metabolism and incorporation into DNA to proceed to the maximum extent possible. In addition, the increased synthesis of ara-CDP-choline associated with these high doses may serve as an alternate substrate for phosphatidyl choline synthesis, which may contribute to membrane fragility and cell lysis. HiDAC also serves as a "prodrug" for high concentrations of ara-U, which in turn diminishes ara-C catabolism with a prolonged gamma phase of systemic clearance and also causes cytostasis in S-phase with enhanced anabolism and cytotoxicity of subsequent doses of ara-C. This metabolite/drug interaction could be termed "self-potentiation," a feature which contributes to the overall activity of HiDAC. Asparaginase enhances these effects in a schedule-dependent fashion by lowering the cellular pool size of dCTP and consequent enhanced metabolism of ara-C. The therapeutic benefit of these pharmacologic manipulations has been verified in a randomized clinical trial in patients with acute myelogenous leukemia. PMID:3163212

  1. Pharmacological targets in the renal peritubular microenvironment: implications for therapy for sepsis-induced acute kidney injury

    PubMed Central

    Mayeux, Philip R.; MacMillan-Crow, Lee Ann

    2012-01-01

    One of the most frequent and serious complications to develop in septic patients is acute kidney injury (AKI), a disorder characterized by a rapid failure of the kidneys to adequately filter the blood, regulate ion and water balance, and generate urine. AKI greatly worsens the already poor prognosis of sepsis and increases cost of care. To date, therapies have been mostly supportive; consequently there has been little change in the mortality rates over the last decade. This is due, at least in part, to the delay in establishing clinical evidence of an infection and the associated presence of the systemic inflammatory response syndrome and thus, a delay in initiating therapy. A second reason is a lack of understanding regarding the mechanisms leading to renal injury, which has hindered the development of more targeted therapies. In this review, we summarize recent studies, which have examined the development of renal injury during sepsis and propose how changes in the peritubular capillary microenvironment lead to and then perpetuate microcirculatory failure and tubular epithelial cell injury. We also discuss a number of potential therapeutic targets in the renal peritubular microenvironment, which may prevent or lessen injury and/or promote recovery. PMID:22274552

  2. Pharmacological inhibition of PTEN attenuates cognitive deficits caused by neonatal repeated exposures to isoflurane via inhibition of NR2B-mediated tau phosphorylation in rats.

    PubMed

    Tan, Lei; Chen, Xin; Wang, Wei; Zhang, Jianfang; Li, Shiyong; Zhao, Yilin; Wang, Jintao; Luo, Ailin

    2017-03-01

    Evidence has shown that children exposed to repeated anesthesia in early childhood display long-term cognitive disabilities. However, the underlying mechanisms remain largely unclear. Our previous study has indicated the involvement of phosphatase and tensin homolog deleted on chromosome 10 (PTEN) in isoflurane-induced decrease of self-renewal capacity in hippocampal neural precursor cells. Additionally, it is demonstrated by others that PTEN inhibition could protect against cognitive impairment via reduction of tau phosphorylation in the alzheimer's disease model. Therefore, in the present in vivo study, we aimed to examine the effects of PTEN inhibition on the cognitive dysfunction and tau hyperphosphorylation caused by neonatal repeated exposures to isoflurane. Our results showed that the neonatal repeated exposures to isoflurane resulted in the activation of PTEN in the hippocampus. The treatment of PTEN inhibitor BPV (pic) restored PSD-95 synthesis, and attenuated tau phosphorylation as well as the cognitive dysfunction caused by the repeated isoflurane exposures. In addition, BPV (pic) treatment reversed the activation of NR2B-containing NMDARs induced by repeated isoflurane exposures, while in turn, the antagonism of NR2B subunit with ifenprodil alleviated tau phosphorylation, indicating a possible role of NR2B as the downstream of PTEN in mediating tau phosphorylation in the neonatal rats repeatedly exposed to isoflurane. In conclusion, our results reveal a novel role of PTEN in mediating tau phosphorylation and cognitive deficits caused by neonatal repeated exposures to isoflurane, implying that targeting on PTEN may be a potential therapeutic approach for the anesthetic-related cognitive decline in the developing brain.

  3. Acute corticosterone sexually dimorphically facilitates social learning and inhibits feeding in mice.

    PubMed

    Choleris, Elena; Cazzin, Laura; Lymer, Jennifer M; Amor, Talya R; Lu, Ray; Kavaliers, Martin; Valsecchi, Paola

    2013-12-01

    In numerous species social learning is predominant and adaptive, yet, we know little of its neurobiological mechanisms. Social learning is modulated by motivations and emotions, in a manner that is often sexually dimorphic. Additionally, stress hormones acutely modulate the related social cognitive process of social recognition. Whether this is true even for social learning is currently unknown. We investigated the acute effects of the stress hormone corticosterone (CORT) on the social transmission of food preferences (STFP) in male and female mice. During a brief social interaction an observer (OBS) acquires a food preference from a same-sex demonstrator (DEM). CORT (1.0, 2.5, 5.0 mg/kg), its ethanol vehicle (0.1%), and saline solution (0.9%) were administered intraperitoneally to the OBS, 10 min before a 30-min social interaction. Levels of plasma CORT were assessed in other mice that had received the same doses of CORT and either had or had not gone through a 30 min social interaction 10 min post-treatment. Exogenous CORT elicited levels of plasma level comparable to those seen at the peak of the circadian cycle and facilitated the STFP with males responding more than females both in terms of the duration of the food preference and the minimum effective dose. CORT also sexually dimorphically inhibited feeding, with females showing a greater dose-response than males. Saline solution and ethanol vehicles also sexually dimorphically facilitated the STFP and reduced feeding, but less than CORT did. These results indicate that CORT facilitates social learning, like social recognition. Hence, CORT may generally increase social information processing.

  4. Pathophysiological regulation of renal SLC22A organic ion transporters in acute kidney injury: pharmacological and toxicological implications.

    PubMed

    Saito, Hideyuki

    2010-01-01

    The kidneys play a primary role in maintaining homeostasis and detoxification of diverse hydrophilic xenobiotics as well as endogenous by-products. Solute carrier (SLC)22A organic ion transporter family members mediate renal excretion of both endogenous and exogenous substances. Thus, the functional and molecular variations of renal SLC22A transporters under acute kidney injury (AKI) have an impact on systemic clearance of their substrate drugs, resulting in altered pharmacokinetics or unexpected adverse events caused by the accumulation of drugs. Recently, there have been significant advances in our understanding of the regulatory mechanisms for transcription, membrane trafficking and/or kidney-specific expression of SLC22A6/OAT1, SLC22A8/OAT3 and SLC22A2/OCT2. Hepatocyte nuclear factor (HNF)-1alpha/beta and HNF-4 appear to play key roles in the transcriptional regulation of OAT1 and OAT3. Furthermore, OAT1 activity/function is modulated via phosphorylation mediated by protein kinase C (PKC) and mitogen-activated protein kinase (MAPK)/extracellular signal-regulated kinase (ERK) pathways. AKI affects renal disposition of organic ions in association with the deteriorated glomerular filtration and tubular transport functions. Thus, dysfunctional regulation of SLC22A transporters during AKI induced by ischemia or toxicants, such as cisplatin, inorganic mercury or uranyl nitrate, cause uremic syndromes or adverse drug reactions. Indoxyl sulfate, a uremic toxin and substrate of OAT1 and OAT3, appears to mediate the progression of AKI evoked by renal ischemia and cisplatin treatment. Precise mechanisms for regulation of the SLC22A transporters in AKI require studies based on the transcription, trafficking, phosphorylation and endogenous factor-dependent modulation. Such analysis will provide a better understanding of the pathophysiological implications of SLC22A transporters.

  5. Increase in SGLT1-mediated transport explains renal glucose reabsorption during genetic and pharmacological SGLT2 inhibition in euglycemia.

    PubMed

    Rieg, Timo; Masuda, Takahiro; Gerasimova, Maria; Mayoux, Eric; Platt, Kenneth; Powell, David R; Thomson, Scott C; Koepsell, Hermann; Vallon, Volker

    2014-01-01

    In the kidney, the sodium-glucose cotransporters SGLT2 and SGLT1 are thought to account for >90 and ∼3% of fractional glucose reabsorption (FGR), respectively. However, euglycemic humans treated with an SGLT2 inhibitor maintain an FGR of 40-50%, mimicking values in Sglt2 knockout mice. Here, we show that oral gavage with a selective SGLT2 inhibitor (SGLT2-I) dose dependently increased urinary glucose excretion (UGE) in wild-type (WT) mice. The dose-response curve was shifted leftward and the maximum response doubled in Sglt1 knockout (Sglt1-/-) mice. Treatment in diet with the SGLT2-I for 3 wk maintained 1.5- to 2-fold higher urine glucose/creatinine ratios in Sglt1-/- vs. WT mice, associated with a temporarily greater reduction in blood glucose in Sglt1-/- vs. WT after 24 h (-33 vs. -11%). Subsequent inulin clearance studies under anesthesia revealed free plasma concentrations of the SGLT2-I (corresponding to early proximal concentration) close to the reported IC50 for SGLT2 in mice, which were associated with FGR of 64 ± 2% in WT and 17 ± 2% in Sglt1-/-. Additional intraperitoneal application of the SGLT2-I (maximum effective dose in metabolic cages) increased free plasma concentrations ∼10-fold and reduced FGR to 44 ± 3% in WT and to -1 ± 3% in Sglt1-/-. The absence of renal glucose reabsorption was confirmed in male and female Sglt1/Sglt2 double knockout mice. In conclusion, SGLT2 and SGLT1 account for renal glucose reabsorption in euglycemia, with 97 and 3% being reabsorbed by SGLT2 and SGLT1, respectively. When SGLT2 is fully inhibited by SGLT2-I, the increase in SGLT1-mediated glucose reabsorption explains why only 50-60% of filtered glucose is excreted.

  6. The Effects of Pharmacological Inhibition of Histone Deacetylase 3 (HDAC3) in Huntington’s Disease Mice

    PubMed Central

    Jia, Haiqun; Wang, Ying; Morris, Charles D.; Jacques, Vincent; Gottesfeld, Joel M.; Rusche, James R.; Thomas, Elizabeth A.

    2016-01-01

    An important epigenetic modification in Huntington’s disease (HD) research is histone acetylation, which is regulated by histone acetyltransferase and histone deacetylase (HDAC) enzymes. HDAC inhibitors have proven effective in HD model systems, and recent work is now focused on functional dissection of the individual HDAC enzymes in these effects. Histone deacetylase 3 (HDAC3), a member of the class I subfamily of HDACs, has previously been implicated in neuronal toxicity and huntingtin-induced cell death. Hence, we tested the effects of RGFP966 ((E)-N-(2-amino-4-fluorophenyl)-3-(1-cinnamyl-1H-pyrazol-4-yl)acrylamide), a benzamide-type HDAC inhibitor that selectively targets HDAC3, in the N171-82Q transgenic mouse model of HD. We found that RGFP966 at doses of 10 and 25 mg/kg improves motor deficits on rotarod and in open field exploration, accompanied by neuroprotective effects on striatal volume. In light of previous studies implicating HDAC3 in immune function, we measured gene expression changes for 84 immune-related genes elicited by RGFP966 using quantitative PCR arrays. RGFP966 treatment did not cause widespread changes in cytokine/chemokine gene expression patterns, but did significantly alter the striatal expression of macrophage migration inhibitory factor (Mif), a hormone immune modulator associated with glial cell activation, in N171-82Q transgenic mice, but not WT mice. Accordingly, RGFP966-treated mice showed decreased glial fibrillary acidic protein (GFAP) immunoreactivity, a marker of astrocyte activation, in the striatum of N171-82Q transgenic mice compared to vehicle-treated mice. These findings suggest that the beneficial actions of HDAC3 inhibition could be related, in part, with lowered Mif levels and its associated downstream effects. PMID:27031333

  7. Acute inhibition of NCC does not activate distal electrogenic Na+ reabsorption or kaliuresis

    PubMed Central

    Craigie, Eilidh; Homer, Natalie Z. M.; Mullins, John J.; Bailey, Matthew A.

    2014-01-01

    Na+ reabsorption from the distal renal tubule involves electroneutral and electrogenic pathways, with the latter promoting K+ excretion. The relative activities of these two pathways are tightly controlled, participating in the minute-to-minute regulation of systemic K+ balance. The pathways are interdependent: the activity of the NaCl cotransporter (NCC) in the distal convoluted tubule influences the activity of the epithelial Na+ channel (ENaC) downstream. This effect might be mediated by changes in distal Na+ delivery per se or by molecular and structural adaptations in the connecting tubule and collecting ducts. We hypothesized that acute inhibition of NCC activity would cause an immediate increase in Na+ flux through ENaC, with a concomitant increase in renal K+ excretion. We tested this using renal clearance methodology in anesthetized mice, by the administration of hydrochlorothiazide (HCTZ) and/or benzamil (BZM) to exert specific blockade of NCC and ENaC, respectively. Bolus HCTZ elicited a natriuresis that was sustained for up to 110 min; urinary K+ excretion was not affected. Furthermore, the magnitude of the natriuresis was no greater during concomitant BZM administration. This suggests that ENaC-mediated Na+ reabsorption was not normally limited by Na+ delivery, accounting for the absence of thiazide-induced kaliuresis. After dietary Na+ restriction, HCTZ elicited a kaliuresis, but the natiuretic effect of HCTZ was not enhanced by BZM. Our findings support a model in which inhibition of NCC activity does not increase Na+ reabsorption through ENaC solely by increasing distal Na+ delivery but rather by inducing a molecular and structural adaptation in downstream nephron segments. PMID:24402096

  8. Phagocytosis by macrophages and endothelial cells inhibits procoagulant and fibrinolytic activity of acute promyelocytic leukemia cells.

    PubMed

    Xie, Rui; Gao, Chunyan; Li, Wen; Zhu, Jiuxin; Novakovic, Valerie; Wang, Jing; Ma, Ruishuang; Zhou, Jin; Gilbert, Gary E; Shi, Jialan

    2012-03-08

    The coagulopathy of acute promyelocytic leukemia (APL) is mainly related to procoagulant substances and fibrinolytic activators of APL blasts, but the fate of these leukemic cells is unknown. The aim of this study was to investigate the removal of APL blasts by macrophages and endothelial cells in vitro and consequent procoagulant and fibrinolytic activity of APL cells. We found that human umbilical vein endothelial cells as well as THP-1 and monocyte-derived macrophages bound, engulfed, and subsequently degraded immortalized APL cell line NB4 and primary APL cells. Lactadherin promoted phagocytosis of APL cells in a time-dependent fashion. Furthermore, factor Xa and prothrombinase activity of phosphatidylserine-exposed target APL cells was time-dependently decreased after incubation with phagocytes (THP-1-derived macrophages or HUVECs). Thrombin production on target APL cells was reduced by 40%-45% after 2 hours of coincubation with phagocytes and 80% by a combination of lactadherin and phagocytes. Moreover, plasmin generation of target APL cells was inhibited 30% by 2 hours of phagocytosis and ∼ 50% by lactadherin-mediated engulfment. These results suggest that engulfment by macrophages and endothelial cells reduce procoagulant and fibrinolytic activity of APL blasts. Lactadherin and phagocytosis could cooperatively ameliorate the clotting disorders in APL.

  9. Baicalin Inhibits Renal Cell Apoptosis and Protects Against Acute Kidney Injury in Pediatric Sepsis

    PubMed Central

    Zhu, Yanping; Fu, Yanxia; Lin, Hairong

    2016-01-01

    Background Pediatric sepsis has high morbidity in children, may lead to acute kidney injury (AKI), and further aggravate the disease. Baicalin is a kind of flavonoid in Scutellaria baicalensis Georgi and has been reported to protect against several diseases, but its roles in septic AKI remain unclear. This study aimed to uncover the effects of baicalin in AKI during pediatric sepsis. Material/Methods Blood urea nitrogen (BUN) and serum creatinine (Cr) levels were detected in 50 pediatric patients, who underwent basic therapy with or without baicalin adjunctive therapy. Mouse sepsis models were constructed by cecal ligation and puncture (CLP) and treated with baicalin intragastrically, after which BUN and Cr examination, TUNEL apoptosis assay, and expression analyses of BAX and BCL2 were performed. Results Baicalin adjunctive therapy significantly decreased BUN and Cr levels in pediatric sepsis patients (P<0.05). CLP led to elevated BUN and Cr levels in the mouse model (P<0.01), indicating kidney injury accompanied by sepsis. Baicalin decreased BUN and Cr levels (P<0.05), and reduced the apoptotic cell percent in the renal tissue (P<0.05) of the CLP model. It inhibited BAX and promoted BCL2 in the renal tissue, which was consistent with cell apoptosis changes. Conclusions Baicalin is capable of suppressing renal cell apoptosis and protecting against AKI in pediatric sepsis. This study provides a potential adjunctive therapy for treating AKI in pediatric sepsis, and further research is necessary to reveal its deeper mechanisms. PMID:28013315

  10. Dexmedetomidine attenuates acute lung injury induced by lipopolysaccharide in mouse through inhibition of MAPK pathway.

    PubMed

    Xu, Yingzhen; Zhang, Ruyi; Li, Chunli; Yin, Xue; Lv, Changjun; Wang, Yaoqi; Zhao, Wenxiang; Zhang, Xiuli

    2015-10-01

    Dexmedetomidine (Dex) is widely used for sedation in intensive care units and can be used as an adjunct to anesthetics. Previous studies have demonstrated that Dex has anti-inflammatory property. In this study, we aim to explore the potential therapeutic effects and mechanisms of Dex on lipopolysaccharide (LPS)-induced acute lung injury (ALI) in mice. To induce ALI, mice were intraperitoneally injected with LPS, while Dex was treated 1 h before LPS injection. The inflammation of lung tissues was evaluated by HE stain, and bronchoalveolar lavage fluid (BALF) was obtained after 6 h to measure protein concentrations. We also used an enzyme-linked immunosorbent assay to detect the secretion levels of proinflammatory cytokines in the serum. Western blotting method was adopted to observe changes in mitogen-activated protein kinases and downstream nuclear transcription factors. The results showed that pretreatment with Dex considerably reduced neutrophil infiltration and pulmonary edema, and significantly reduced protein concentrations in the BALF, as well as suppressed LPS-induced elevation of proinflammatory cytokines (TNF-α and IL-1β) in the serum. In addition, we observed that the molecular mechanism of Dex-mediated anti-inflammation is associated with decreasing phosphorylation of MKK4, MMK3/6, ERK1/2, p38MAPK, and JNK, and diminishing activation of Elk-1, c-Jun, and ATF-2. Dex could attenuate ALI induced by LPS in mice, and this effect may be mediated through the inhibition of MAPK pathway.

  11. Guggulsterone attenuates cerulein-induced acute pancreatitis via inhibition of ERK and JNK activation.

    PubMed

    Kim, Dong-Goo; Bae, Gi-Sang; Choi, Sun-Bok; Jo, Il-Joo; Shin, Joon-Yeon; Lee, Sung-Kon; Kim, Myoung-Jin; Kim, Min-Jun; Jeong, Hyun-Woo; Choi, Chang-Min; Seo, Seung-Hee; Choo, Gab-Chul; Seo, Sang-Wan; Song, Ho-Joon; Park, Sung-Joo

    2015-05-01

    Guggulsterone (GS), a plant steroid and a compound found at high levels in Commiphora myrrha, exhibits anti-inflammatory, anti-cancer, and cholesterol-lowering effects. However, the potential of GS to ameliorate acute pancreatitis (AP) is unknown. The aim of this study was to evaluate the effects of GS on cerulein-induced AP. AP was induced by intraperitoneally injecting supramaximal concentrations of the stable cholecystokinin analog cerulein (50 μg/kg) hourly for 6 h. In the GS-treated group, GS was administered intraperitoneally (10, 25, or 50mg/kg) 1 h before the first cerulein injection. Mice were sacrificed 6 h after the final cerulein injection. Blood samples were collected to measure serum lipase levels and evaluate cytokine production. The pancreas and lung were rapidly removed for morphologic and histological examinations, flow cytometry analysis, myeloperoxidase (MPO) assay, and real-time reverse transcription-polymerase chain reaction analysis. Pre-treatment with GS attenuated cerulein-induced histological damage, reduced pancreas weight/body weight ratio, decreased serum lipase levels, inhibited infiltrations of macrophages and neutrophils, and suppressed cytokine production. Additionally, GS treatment suppressed the activation of extracellular signal-regulated protein kinase (ERK) and c-Jun N-terminal kinase (JNK) in the pancreas in cerulein-induced pancreatitis. In conclusion, our results suggest that GS attenuates AP via deactivation of ERK and JNK.

  12. HOX gene expression predicts response to BCL-2 inhibition in acute myeloid leukemia.

    PubMed

    Kontro, M; Kumar, A; Majumder, M M; Eldfors, S; Parsons, A; Pemovska, T; Saarela, J; Yadav, B; Malani, D; Fløisand, Y; Höglund, M; Remes, K; Gjertsen, B T; Kallioniemi, O; Wennerberg, K; Heckman, C A; Porkka, K

    2017-02-01

    Inhibitors of B-cell lymphoma-2 (BCL-2) such as venetoclax (ABT-199) and navitoclax (ABT-263) are clinically explored in several cancer types, including acute myeloid leukemia (AML), to selectively induce apoptosis in cancer cells. To identify robust biomarkers for BCL-2 inhibitor sensitivity, we evaluated the ex vivo sensitivity of fresh leukemic cells from 73 diagnosed and relapsed/refractory AML patients, and then comprehensively assessed whether the responses correlated to specific mutations or gene expression signatures. Compared with samples from healthy donor controls (nonsensitive) and chronic lymphocytic leukemia (CLL) patients (highly sensitive), AML samples exhibited variable responses to BCL-2 inhibition. Strongest CLL-like responses were observed in 15% of the AML patient samples, whereas 32% were resistant, and the remaining exhibited intermediate responses to venetoclax. BCL-2 inhibitor sensitivity was associated with genetic aberrations in chromatin modifiers, WT1 and IDH1/IDH2. A striking selective overexpression of specific HOXA and HOXB gene transcripts were detected in highly BCL-2 inhibitor sensitive samples. Ex vivo responses to venetoclax showed significant inverse correlation to β2-microglobulin expression and to a lesser degree to BCL-XL and BAX expression. As new therapy options for AML are urgently needed, the specific HOX gene expression pattern can potentially be used as a biomarker to identify venetoclax-sensitive AML patients for clinical trials.

  13. NF-κB transcriptional inhibition ameliorates cisplatin-induced acute kidney injury (AKI).

    PubMed

    Ozkok, Abdullah; Ravichandran, Kameswaran; Wang, Qian; Ljubanovic, Danica; Edelstein, Charles L

    2016-01-05

    The nuclear factor kappa-light-chain-enhancer of activated B cells (NF-κB) cell signaling pathway is important in inflammation and cell survival. Inflammation and cell death in the kidney are features of cisplatin-induced AKI. While it is known that cisplatin induces NF-κB signaling in the kidney, the NF-κB responsive genes and the effect of direct NF-κB transcriptional inhibition in cisplatin-induced AKI is not known. Mice injected with cisplatin, 25mg/kg, developed AKI, acute tubular necrosis (ATN) and apoptosis on day 3. Mice were treated with JSH-23 (20 or 40 mg/kg) which directly affects NF-κB transcriptional activity. Kidney function, tubular injury (ATN, serum neutrophil gelatinase-associated lipocalin [NGAL], but not apoptosis) and myeloperoxidase (MPO) activity were significantly improved by JSH-23 (40 mg/kg). Sixty one NF-κB responsive genes were increased by cisplatin of which 21 genes were decreased by JSH-23. Genes that were decreased by JSH-23 that are known to play a role in cisplatin-induced AKI were IL-10, IFN-γ, chemokine [C-C motif] ligand 2 (CCL2) and caspase-1. Another gene, caspase recruitment domain family, member 11 (CARD11), not previously known to play a role in AKI, was increased more than 20-fold and completely inhibited by JSH-23. CXCL1 and TNF-α, known mediators of cisplatin-induced AKI, were decreased by JSH-23. RIPK1 and 3, receptor-interacting serine/threonine-protein kinases, that play an important role in necroptosis, were decreased by JSH-23. In mouse proximal tubule cells in culture, JSH-23 resulted in an increase in apoptosis suggesting that the mechanism of protection against AKI by JSH-23 is not due to a direct effect on proximal tubules. In conclusion, NF-κB transcriptional inhibition in cisplatin-induced AKI ameliorates kidney function and ATN without a significant effect on apoptosis and is associated with a decrease pro-inflammatory mediators and CARD11.

  14. Monitoring Pharmacologically Induced Immunosuppression by Immune Repertoire Sequencing to Detect Acute Allograft Rejection in Heart Transplant Patients: A Proof-of-Concept Diagnostic Accuracy Study

    PubMed Central

    Valantine, Hannah A.; Penland, Lolita; Luikart, Helen; Strehl, Calvin; Cohen, Garrett; Khush, Kiran K.; Quake, Stephen R.

    2015-01-01

    Background It remains difficult to predict and to measure the efficacy of pharmacological immunosuppression. We hypothesized that measuring the B-cell repertoire would enable assessment of the overall level of immunosuppression after heart transplantation. Methods and Findings In this proof-of-concept study, we implemented a molecular-barcode-based immune repertoire sequencing assay that sensitively and accurately measures the isotype and clonal composition of the circulating B cell repertoire. We used this assay to measure the temporal response of the B cell repertoire to immunosuppression after heart transplantation. We selected a subset of 12 participants from a larger prospective cohort study (ClinicalTrials.gov NCT01985412) that is ongoing at Stanford Medical Center and for which enrollment started in March 2010. This subset of 12 participants was selected to represent post-heart-transplant events, with and without acute rejection (six participants with moderate-to-severe rejection and six without). We analyzed 130 samples from these patients, with an average follow-up period of 15 mo. Immune repertoire sequencing enables the measurement of a patient’s net state of immunosuppression (correlation with tacrolimus level, r = −0.867, 95% CI −0.968 to −0.523, p = 0.0014), as well as the diagnosis of acute allograft rejection, which is preceded by increased immune activity with a sensitivity of 71.4% (95% CI 30.3% to 94.9%) and a specificity of 82.0% (95% CI 72.1% to 89.1%) (cell-free donor-derived DNA as noninvasive gold standard). To illustrate the potential of immune repertoire sequencing to monitor atypical post-transplant trajectories, we analyzed two more patients, one with chronic infections and one with amyloidosis. A larger, prospective study will be needed to validate the power of immune repertoire sequencing to predict rejection events, as this proof-of-concept study is limited to a small number of patients who were selected based on several

  15. Acute ethanol administration inhibits Toll-like receptor 4 signaling pathway in rat intestinal epithelia.

    PubMed

    Zhou, Chao; Zhao, Ji; Li, Jing; Wang, Haiying; Tang, Chengwei

    2013-05-01

    Excess alcohol intake, as in binge drinking, increases susceptibility to microbial pathogens. Alcohol impairs macrophage function by suppression of the Toll-like receptor 4 (TLR4) pathway. This study investigated the effects of acute ethanol intake on the TLR4 pathway in rat intestinal epithelia, which usually encounters luminal antigens at first and participates in the development of intestinal immunity. Twenty Wistar rats were randomly assigned to an ethanol group given ethanol as a 25% (v/v) solution in water at 7.5 g/kg, or a control group given saline, by oral gavage daily for 3 days. The epithelial histology and ultrastructure, the intestinal microflora, peripheral and portal venous plasma lipopolysaccharide (LPS) levels, and somatostatin (SST) levels in the peripheral plasma and small intestine were evaluated. Somatostatin receptor 2 (SSTR2), TLR4, TANK binding kinase-1 (TBK1), activated nuclear factor-κB (NF-κB), interferon-γ (IFN-γ) and tumor necrosis factor-α (TNF-α) in the intestinal mucosa were assayed. LPS responsiveness with or without SST pretreatment was assayed in vitro by quantification of TLR4, TBK1, activated NF-κB, IFN-γ and TNF-α in isolated intestinal epithelia. Mucosal damage was observed in the ethanol group by light and electron microscopy. Escherichia coli cultures were unchanged in rat intestine of the ethanol group compared with controls, but lactobacilli cultures were reduced (p < 0.05). LPS levels increased in peripheral and portal venous plasma (p < 0.05), but mucosal TLR4, TBK1, nuclear NF-κB, IFN-γ and TNF-α were unchanged in the ethanol group. LPS treatment in vitro up-regulated the level of TLR4, TBK1 and nuclear NF-κB as well as the production of IFN-γ and TNF-α in isolated intestinal epithelia in the control (p < 0.05), but not the ethanol group. The stimulatory effects of LPS on intestinal epithelia isolated from the control group were significantly inhibited by SST pretreatment (p < 0.05). The

  16. Mechanisms responsible for the synergistic antileukemic interactions between ATR inhibition and cytarabine in acute myeloid leukemia cells

    PubMed Central

    Ma, Jun; Li, Xinyu; Su, Yongwei; Zhao, Jianyun; Luedtke, Daniel A.; Epshteyn, Valeria; Edwards, Holly; Wang, Guan; Wang, Zhihong; Chu, Roland; Taub, Jeffrey W.; Lin, Hai; Wang, Yue; Ge, Yubin

    2017-01-01

    Acute myeloid leukemia (AML) continues to be a challenging disease to treat, thus new treatment strategies are needed. In this study, we investigated the antileukemic effects of ATR inhibition alone or combined with cytarabine in AML cells. Treatment with the ATR-selective inhibitor AZ20 caused proliferation inhibition in AML cell lines and primary patient samples. It partially abolished the G2 cell cycle checkpoint and caused DNA replication stress and damage, accompanied by CDK1-independent apoptosis and downregulation of RRM1 and RRM2. AZ20 synergistically enhanced cytarabine-induced proliferation inhibition and apoptosis, abolished cytarabine-induced S and G2/M cell cycle arrest, and cooperated with cytarabine in inducing DNA replication stress and damage in AML cell lines. These key findings were confirmed with another ATR-selective inhibitor AZD6738. Therefore, the cooperative induction of DNA replication stress and damage by ATR inhibition and cytarabine, and the ability of ATR inhibition to abrogate the G2 cell cycle checkpoint both contributed to the synergistic induction of apoptosis and proliferation inhibition in AML cell lines. Synergistic antileukemic interactions between AZ20 and cytarabine were confirmed in primary AML patient samples. Our findings provide insight into the mechanism of action underlying the synergistic antileukemic activity of ATR inhibition in combination with cytarabine in AML. PMID:28176818

  17. Effects of chronic nitric oxide synthase inhibition on responses to acute exercise in swine.

    PubMed

    McAllister, Richard M; Newcomer, Sean C; Pope, Eric R; Turk, James R; Laughlin, M Harold

    2008-01-01

    Nitric oxide (NO) is potentially involved in several responses to acute exercise. We tested the hypotheses that inhibition of NO formation reduces maximal O(2) delivery to muscle, but does not affect O(2) utilization by muscle, therefore lowering maximal O(2) consumption. To test these hypotheses, swine (approximately 30 kg) drank either tap water (Con, n = 25) or water with N(G)-nitro-l-arginine methyl ester (8.0 +/- 0.4 mg x kg(-1) x day(-1) for >or=4 wk; LN, n = 24). Treatment efficacy was reflected by higher mean arterial pressure and lower plasma NO metabolite concentration in LN than Con (both P < 0.05). Swine completed two graded treadmill running tests to maximum. In the first test, O(2) consumption was determined at rest through maximal exercise intensity. O(2) consumption did not differ between groups at rest or at most exercise intensities, including maximum (Con, 40.8 +/- 1.8 ml x min(-1) x kg(-1); LN, 40.4 +/- 2.9; not significant). In the second test, tissue-specific blood flows were determined using the radiolabeled-microsphere technique. At rest, blood flows were lower (P < 0.05) in LN compared with Con for a number of tissues, including kidney, adrenal, lung, and several skeletal muscles. During both submaximal and maximal exercise, however, blood flows were similar between Con and LN for all 16 muscles examined; only blood flows to kidney (Con, 99 +/- 16 ml x min(-1) x 100 g; LN, 55 +/- 15; P < 0.05) and pancreas (Con, 25 +/- 7; LN, 6 +/- 2; P < 0.05) were lower in LN at maximum. Endothelium-dependent, but not -independent, relaxation of renal arterial segments was reduced (P < 0.05) in vitro. These data indicate that exercise-induced increases in muscle blood flows are maintained with chronic inhibition of NO formation and that maximal O(2) consumption is therefore preserved. Redundant vasodilatory pathways and/or upregulation of these pathways may underlie these findings.

  18. Effects of chronic nitric oxide synthase inhibition on responses to acute exercise in swine

    PubMed Central

    McAllister, Richard M.; Newcomer, Sean C.; Pope, Eric R.; Turk, James R.; Laughlin, M. Harold

    2012-01-01

    Nitric oxide (NO) is potentially involved in several responses to acute exercise. We tested the hypotheses that inhibition of NO formation reduces maximal O2 delivery to muscle, but does not affect O2 utilization by muscle, therefore lowering maximal O2 consumption. To test these hypotheses, swine (~30 kg) drank either tap water (Con, n = 25) or water with NG-nitro-L-arginine methyl ester (8.0 ± 0.4 mg · kg−1 · day−1 for ≥4 wk; LN, n = 24). Treatment efficacy was reflected by higher mean arterial pressure and lower plasma NO metabolite concentration in LN than Con (both P < 0.05). Swine completed two graded treadmill running tests to maximum. In the first test, O2 consumption was determined at rest through maximal exercise intensity. O2 consumption did not differ between groups at rest or at most exercise intensities, including maximum (Con, 40.8 ± 1.8 ml · min−1 · kg−1; LN, 40.4 ± 2.9; not significant). In the second test, tissue-specific blood flows were determined using the radiolabeled-microsphere technique. At rest, blood flows were lower (P < 0.05) in LN compared with Con for a number of tissues, including kidney, adrenal, lung, and several skeletal muscles. During both submaximal and maximal exercise, however, blood flows were similar between Con and LN for all 16 muscles examined; only blood flows to kidney (Con, 99 ± 16 ml · min−1 · 100 g; LN, 55 ± 15; P < 0.05) and pancreas (Con, 25 ± 7; LN, 6 ± 2; P < 0.05) were lower in LN at maximum. Endothelium-dependent, but not -independent, relaxation of renal arterial segments was reduced (P < 0.05) in vitro. These data indicate that exercise-induced increases in muscle blood flows are maintained with chronic inhibition of NO formation and that maximal O2 consumption is therefore preserved. Redundant vasodilatory pathways and/or upregulation of these pathways may underlie these findings. PMID:17975123

  19. The Ly49E Receptor Inhibits the Immune Control of Acute Trypanosoma cruzi Infection

    PubMed Central

    Filtjens, Jessica; Coltel, Nicolas; Cencig, Sabrina; Taveirne, Sylvie; Van Ammel, Els; Van Acker, Aline; Kerre, Tessa; Matthys, Patrick; Taghon, Tom; Vandekerckhove, Bart; Carlier, Yves; Truyens, Carine; Leclercq, Georges

    2016-01-01

    The protozoan parasite Trypanosoma cruzi circulates in the blood upon infection and invades various cells. Parasites intensively multiply during the acute phase of infection and persist lifelong at low levels in tissues and blood during the chronic phase. Natural killer (NK) and NKT cells play an important role in the immune control of T. cruzi infection, mainly by releasing the cytokine IFN-γ that activates the microbicidal action of macrophages and other cells and shapes a protective type 1 immune response. The mechanisms by which immune cells are regulated to produce IFN-γ during T. cruzi infection are still incompletely understood. Here, we show that urokinase plasminogen activator (uPA) is induced early upon T. cruzi infection and remains elevated until day 20 post-infection. We previously demonstrated that the inhibitory receptor Ly49E, which is expressed, among others, on NK and NKT cells, is triggered by uPA. Therefore, we compared wild type (WT) to Ly49E knockout (KO) mice for their control of experimental T. cruzi infection. Our results show that young, i.e., 4- and 6-week-old, Ly49E KO mice control the infection better than WT mice, indicated by a lower parasite load and less cachexia. The beneficial effect of Ly49E depletion is more obvious in 4-week-old male than in female mice and weakens in 8-week-old mice. In young mice, the lower T. cruzi parasitemia in Ly49E KO mice is paralleled by higher IFN-γ production compared to their WT controls. Our data indicate that Ly49E receptor expression inhibits the immune control of T. cruzi infection. This is the first demonstration that the inhibitory Ly49E receptor can interfere with the immune response to a pathogen in vivo. PMID:27891126

  20. Healthspan Pharmacology

    PubMed Central

    2015-01-01

    Abstract The main goal of this paper is to present the case for shifting the focus of research on aging and anti-aging from lifespan pharmacology to what I like to call healthspan pharmacology, in which the desired outcome is the extension of healthy years of life rather than lifespan alone. Lifespan could be influenced by both genetic and epigenetic factors, but a long lifespan may not be a good indicator of an optimal healthspan. Without improving healthspan, prolonging longevity would have enormous negative socioeconomic outcomes for humans. Therefore, the goal of aging and anti-aging research should be to add healthy years to life and not merely to increase the chronological age. This article summarizes and compares two categories of pharmacologically induced lifespan extension studies in animal model systems from the last two decades—those reporting the effects of pharmacological interventions on lifespan extension alone versus others that include their effects on both lifespan and healthspan in the analysis. The conclusion is that the extrapolation of pharmacological results from animal studies to humans is likely to be more relevant when both lifespan and healthspan extension properties of pharmacological intervention are taken into account. PMID:26444965

  1. Healthspan Pharmacology.

    PubMed

    Jafari, Mahtab

    2015-12-01

    The main goal of this paper is to present the case for shifting the focus of research on aging and anti-aging from lifespan pharmacology to what I like to call healthspan pharmacology, in which the desired outcome is the extension of healthy years of life rather than lifespan alone. Lifespan could be influenced by both genetic and epigenetic factors, but a long lifespan may not be a good indicator of an optimal healthspan. Without improving healthspan, prolonging longevity would have enormous negative socioeconomic outcomes for humans. Therefore, the goal of aging and anti-aging research should be to add healthy years to life and not merely to increase the chronological age. This article summarizes and compares two categories of pharmacologically induced lifespan extension studies in animal model systems from the last two decades-those reporting the effects of pharmacological interventions on lifespan extension alone versus others that include their effects on both lifespan and healthspan in the analysis. The conclusion is that the extrapolation of pharmacological results from animal studies to humans is likely to be more relevant when both lifespan and healthspan extension properties of pharmacological intervention are taken into account.

  2. Silvestrol exhibits significant in vivo and in vitro antileukemic activities and inhibits FLT3 and miR-155 expressions in acute myeloid leukemia

    PubMed Central

    2013-01-01

    Background Activating mutations [internal tandem duplication (ITD)] or overexpression of the FMS-like tyrosine kinase receptor-3 (FLT3) gene are associated with poor outcome in acute myeloid leukemia (AML) patients, underscoring the need for novel therapeutic approaches. The natural product silvestrol has potent antitumor activity in several malignancies, but its therapeutic impact on distinct molecular high-risk AML subsets remains to be fully investigated. We examined here the preclinical activity of silvestrol in FLT3-ITD and FLT3 wild-type (wt) AML. Methods Silvestrol in vitro anti-leukemic activity was examined by colorimetric cell viability assay, colony-forming and flow cytometry assays assessing growth inhibition and apoptosis, respectively. Pharmacological activity of silvestrol on FLT3 mRNA translation, mRNA and protein expression was determined by RNA-immunoprecipitation, qRT-PCR and immunoblot analyses, respectively. Silvestrol in vivo efficacy was investigated using MV4-11 leukemia-engrafted mice. Results Silvestrol shows antileukemia activity at nanomolar concentrations both in FLT3-wt overexpressing (THP-1) and FLT3-ITD (MV4-11) expressing AML cell lines (IC50 = 3.8 and 2.7 nM, respectively) and patients’ primary blasts [IC50 = ~12 nM (FLT3-wt) and ~5 nM (FLT3-ITD)]. Silvestrol increased apoptosis (~4fold, P = 0.0001), and inhibited colony-formation (100%, P < 0.0001) in primary blasts. Silvestrol efficiently inhibited FLT3 translation reducing FLT3 protein expression by 80–90% and decreased miR-155 levels (~60%), a frequently co-regulated onco-miR in FLT3-ITD-positive AML. The median survival of silvestrol-treated vs vehicle-treated mice was 63 vs 29 days post-engraftment, respectively (P < 0.0001). Conclusions Silvestrol exhibits significant in vivo and in vitro antileukemic activities in AML through a novel mechanism resulting in inhibition of FLT3 and miR-155 expression. These encouraging results warrant a rapid

  3. Artemisinin-derived dimer ART-838 potently inhibited human acute leukemias, persisted in vivo, and synergized with antileukemic drugs

    PubMed Central

    Fox, Jennifer M.; Moynihan, James R.; Mott, Bryan T.; Mazzone, Jennifer R.; Anders, Nicole M.; Brown, Patrick A.; Rudek, Michelle A.; Liu, Jun O.; Arav-Boger, Ravit; Posner, Gary H.

    2016-01-01

    Artemisinins, endoperoxide-containing molecules, best known as antimalarials, have potent antineoplastic activity. The established antimalarial, artesunate (AS), and the novel artemisinin-derived trioxane diphenylphosphate dimer 838 (ART-838) inhibited growth of all 23 tested acute leukemia cell lines, reduced cell proliferation and clonogenicity, induced apoptosis, and increased intracellular levels of reactive oxygen species (ROS). ART-838 was 88-fold more potent that AS in vitro, inhibiting all leukemia cell lines at submicromolar concentrations. Both ART-838 and AS cooperated with several established antileukemic drugs and newer kinase inhibitors to inhibit leukemia cell growth. ART-838 had a longer plasma half-life than AS in immunodeficient NOD-SCID-IL2Rgnull (NSG) mice, remaining at effective antileukemic concentrations for >8h. Intermittent cycles of ART-838 inhibited growth of acute leukemia xenografts and primagrafts in NSG mice, at higher potency than AS. Based on these preclinical data, we propose that AS, with its established low toxicity and low cost, and ART-838, with its higher potency and longer persistence in vivo, should be further developed toward integration into antileukemic regimens. PMID:26771236

  4. Artemisinin-derived dimer ART-838 potently inhibited human acute leukemias, persisted in vivo, and synergized with antileukemic drugs.

    PubMed

    Fox, Jennifer M; Moynihan, James R; Mott, Bryan T; Mazzone, Jennifer R; Anders, Nicole M; Brown, Patrick A; Rudek, Michelle A; Liu, Jun O; Arav-Boger, Ravit; Posner, Gary H; Civin, Curt I; Chen, Xiaochun

    2016-02-09

    Artemisinins, endoperoxide-containing molecules, best known as antimalarials, have potent antineoplastic activity. The established antimalarial, artesunate (AS), and the novel artemisinin-derived trioxane diphenylphosphate dimer 838 (ART-838) inhibited growth of all 23 tested acute leukemia cell lines, reduced cell proliferation and clonogenicity, induced apoptosis, and increased intracellular levels of reactive oxygen species (ROS). ART-838 was 88-fold more potent that AS in vitro, inhibiting all leukemia cell lines at submicromolar concentrations. Both ART-838 and AS cooperated with several established antileukemic drugs and newer kinase inhibitors to inhibit leukemia cell growth. ART-838 had a longer plasma half-life than AS in immunodeficient NOD-SCID-IL2Rgnull (NSG) mice, remaining at effective antileukemic concentrations for >8h. Intermittent cycles of ART-838 inhibited growth of acute leukemia xenografts and primagrafts in NSG mice, at higher potency than AS. Based on these preclinical data, we propose that AS, with its established low toxicity and low cost, and ART-838, with its higher potency and longer persistence in vivo, should be further developed toward integration into antileukemic regimens.

  5. Acute inhibition of the cystic fibrosis transmembrane conductance regulator (CFTR) Cl- channel by thyroid hormones involves multiple mechanisms.

    PubMed

    Cai, Zhiwei; Li, Hongyu; Chen, Jeng-Haur; Sheppard, David N

    2013-10-15

    The chemical structures of the thyroid hormones triiodothyronine (T3) and thyroxine (T4) resemble those of small-molecules that inhibit the cystic fibrosis transmembrane conductance regulator (CFTR) Cl(-) channel. We therefore tested the acute effects of T3, T4 and reverse T3 (rT3) on recombinant wild-type human CFTR using the patch-clamp technique. When added directly to the intracellular solution bathing excised membrane patches, T3, T4, and rT3 (all tested at 50 μM) inhibited CFTR in several ways: they strongly reduced CFTR open probability by impeding channel opening; they moderately decreased single-channel current amplitude, and they promoted transitions to subconductance states. To investigate the mechanism of CFTR inhibition, we studied T3. T3 (50 μM) had multiple effects on CFTR gating kinetics, suggestive of both allosteric inhibition and open-channel blockade. Channel inhibition by T3 was weakly voltage dependent and stronger than the allosteric inhibitor genistein, but weaker than the open-channel blocker glibenclamide. Raising the intracellular ATP concentration abrogated T3 inhibition of CFTR gating, but not the reduction in single-channel current amplitude nor the transitions to subconductance states. The decrease in single-channel current amplitude was relieved by membrane depolarization, but not the transitions to subconductance states. We conclude that T3 has complex effects on CFTR consistent with both allosteric inhibition and open-channel blockade. Our results suggest that there are multiple allosteric mechanisms of CFTR inhibition, including interference with ATP-dependent channel gating and obstruction of conformational changes that gate the CFTR pore. CFTR inhibition by thyroid hormones has implications for the development of innovative small-molecule CFTR inhibitors.

  6. Inhibiting Polo-like kinase 1 causes growth reduction and apoptosis in pediatric acute lymphoblastic leukemia cells.

    PubMed

    Hartsink-Segers, Stefanie A; Exalto, Carla; Allen, Matthew; Williamson, Daniel; Clifford, Steven C; Horstmann, Martin; Caron, Huib N; Pieters, Rob; Den Boer, Monique L

    2013-10-01

    This study investigated Polo-like kinase 1, a mitotic regulator often over-expressed in solid tumors and adult hematopoietic malignancies, as a potential new target in the treatment of pediatric acute lymphoblastic leukemia. Polo-like kinase 1 protein and Thr210 phosphorylation levels were higher in pediatric acute lymphoblastic leukemia (n=172) than in normal bone marrow mononuclear cells (n=10) (P<0.0001). High Polo-like kinase 1 protein phosphorylation, but not expression, was associated with a lower probability of event-free survival (P=0.042) and was a borderline significant prognostic factor (P=0.065) in a multivariate analysis including age and initial white blood cell count. Polo-like kinase 1 was necessary for leukemic cell survival, since short hairpin-mediated Polo-like kinase 1 knockdown in acute lymphoblastic leukemia cell lines inhibited cell proliferation by G2/M cell cycle arrest and induced apoptosis through caspase-3 and poly (ADP-ribose) polymerase cleavage. Primary patient cells with a high Polo-like kinase 1 protein expression were sensitive to the Polo-like kinase 1-specific inhibitor NMS-P937 in vitro, whereas cells with a low expression and normal bone marrow cells were resistant. This sensitivity was likely not caused by Polo-like kinase 1 mutations, since only one new mutation (Ser335Arg) was found by 454-sequencing of 38 pediatric acute lymphoblastic leukemia cases. This mutation did not affect Polo-like kinase 1 expression or NMS-P937 sensitivity. Together, these results indicate a pivotal role for Polo-like kinase 1 in pediatric acute lymphoblastic leukemia and show potential for Polo-like kinase 1-inhibiting drugs as an addition to current treatment strategies for cases expressing high Polo-like kinase 1 levels.

  7. Acute Reversal of Phospholamban Inhibition Facilitates the Rhythmic Whole-cell Propagating Calcium Waves in Isolated Ventricular Myocytes

    PubMed Central

    Chan, Yi-Hsin; Tsai, Wei-Chung; Song, Zhen; Ko, Christopher Y.; Qu, Zhilin; Weiss, James N.; Lin, Shien-Fong; Chen, Peng-Sheng; Jones, Larry R.; Chen, Zhenhui

    2015-01-01

    Phospholamban (PLB) inhibits the activity of cardiac sarcoplasmic reticulum (SR) Ca2+-ATPase (SERCA2a). Phosphorylation of PLB during sympathetic activation reverses SERCA2a inhibition, increasing SR Ca2+ uptake. However, sympathetic activation also modulates multiple other intracellular targets in ventricular myocytes (VMs), making it impossible to determine the specific effects of reversal of PLB inhibition on the spontaneous SR Ca2+ release. Therefore, it remains unclear how PLB regulates rhythmic activity in VMs. Here we used the Fab fragment of 2D12, a monoclonal anti-PLB antibody, to test how acute reversal of PLB inhibition affects the spontaneous SR Ca2+ release in normal VMs. Ca2+ sparks and spontaneous Ca2+ waves (SCWs) were recorded in the line-scan mode of confocal microscopy using the Ca2+ fluorescent dye Fluo-4 in isolated permeabilized mouse VMs. Fab, which reverses PLB inhibition, significantly increased the frequency, amplitude, and spatial/temporal spread of Ca2+ sparks in VMs exposed to 50 nM free [Ca2+]. At physiological diastolic free [Ca2+] (100–200 nM), Fab facilitated the formation of whole-cell propagating SCWs. At higher free [Ca2+], Fab increased the frequency and velocity, but decreased the decay time of the SCWs. cAMP had little additional effect on the frequency or morphology of Ca2+ sparks or SCWs after Fab addition. These findings were complemented by computer simulations. In conclusion, acute reversal of PLB inhibition alone significantly increased the spontaneous SR Ca2+ release, leading to the facilitation and organization of whole-cell propagating SCWs in normal VMs. PLB thus plays a key role in subcellular Ca2+ dynamics and rhythmic activity of VMs. PMID:25596331

  8. Ethanol Acutely Inhibits Ionotropic Glutamate Receptor-mediated Responses and Long-Term Potentiation in the Developing CA1 Hippocampus

    PubMed Central

    Puglia, Michael P.; Valenzuela, C. Fernando

    2011-01-01

    Background Developmental ethanol (EtOH) exposure damages the hippocampus, causing long-lasting alterations in learning and memory. Alterations in glutamatergic synaptic transmission and plasticity may play a role in the mechanism of action of EtOH. This signaling is fundamental for synaptogenesis, which occurs during the third-trimester of human pregnancy (first 12 days of life in rats). Methods Acute coronal brain slices were prepared from 7–9 day-old rats. Extracellular and patch-clamp electrophysiological recording techniques were used to characterize the acute effects of EtOH on α-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptor (AMPAR)- and N-methyl-D-aspartate receptor (NMDAR)-mediated responses and long-term potentiation (LTP) in the CA1 hippocampal region. Results EtOH (40 and 80 mM) inhibited AMPAR- and NMDAR-mediated field excitatory postsynaptic potentials (fEPSPs). EtOH (80 mM) also reduced AMPAR-mediated fEPSPs in presence of an inhibitor of Ca2+ permeable AMPARs. The effect of 80 mM EtOH on NMDAR-mediated fEPSPs was significantly greater in presence of Mg2+. EtOH (80 mM) neither affected the paired-pulse ratio of AMPAR-mediated fEPSPs nor the presynaptic volley. The paired-pulse ratio of AMPAR-mediated excitatory postsynaptic currents was not affected either, and the amplitude of these currents was inhibited to a lesser extent than that of fEPSPs. EtOH (80 mM) inhibited LTP of AMPAR-mediated fEPSPs. Conclusions Acute EtOH exposure during the third-trimester equivalent of human pregnancy inhibits hippocampal glutamatergic transmission and LTP induction, which could alter synapse refinement and ultimately contribute to the pathophysiology of fetal alcohol spectrum disorder. PMID:20102565

  9. Pretreatment with low doses of acenocoumarol inhibits the development of acute ischemia/reperfusion-induced pancreatitis.

    PubMed

    Warzecha, Z; Sendur, P; Ceranowicz, P; Dembinski, M; Cieszkowski, J; Kusnierz-Cabala, B; Tomaszewska, R; Dembinski, A

    2015-10-01

    Coagulative disorders are known to occur in acute pancreatitis and are related to the severity of this disease. Various experimental and clinical studies have shown protective and therapeutic effect of heparin in acute pancreatitis. Aim of the present study was to determine the influence of acenocoumarol, a vitamin K antagonist, on the development of acute pancreatitis. Studies were performed on male Wistar rats weighing 250 - 270 g. Acenocoumarol at the dose of 50, 100 or 150 μg/kg/dose or vehicle were administered once a day for 7 days before induction of acute pancreatitis. Acute pancreatitis was induced in rats by pancreatic ischemia followed by reperfusion. The severity of acute pancreatitis was assessed after 5-h reperfusion. Pretreatment with acenocoumarol given at the dose of 50 or 100 μg/kg/dose reduced morphological signs of acute pancreatitis. These effects were accompanied with a decrease in the pancreatitis-evoked increase in serum activity of lipase and serum concentration of pro-inflammatory interleukin-1β. Moreover, the pancreatitis-evoked reductions in pancreatic DNA synthesis and pancreatic blood flow were partially reversed by pretreatment with acenocoumarol given at the dose of 50 and 100 μg/kg/dose. Administration of acenocoumarol at the dose of 150 μg/kg/dose did not exhibit any protective effect against ischemia/reperfusion-induced pancreatitis. We concluded that pretreatment with low doses of acenocoumarol reduces the severity of ischemia/reperfusion-induced acute pancreatitis.

  10. Extended-duration versus short-duration pharmacological thromboprophylaxis in acutely Ill hospitalized medical patients: a systematic review and meta-analysis of randomized controlled trials.

    PubMed

    Liew, Aaron Y L; Piran, Siavash; Eikelboom, John W; Douketis, James D

    2017-04-01

    Extended-duration pharmacological thromboprophylaxis, for at least 28 days, is effective for the prevention of symptomatic venous thromboembolism (VTE) in high-risk surgical patients but is of uncertain benefit in hospitalized medical patients. We aimed to evaluate the efficacy and safety of extended-duration thromboprophylaxis in hospitalized medical patients. We conducted a systematic PubMed, Medline and EMBASE literature search until June 2016 and a meta-analysis of randomized controlled trials which compared extended-duration with short-duration thromboprophylaxis in hospitalized medical patients. Four randomized controlled trials comparing extended-duration prophylaxis (24-47 days) with short-duration prophylaxis (6-14 days) in a total of 34,068 acutely ill hospitalized medical patients were included. When compared with short-duration prophylaxis, extended-duration prophylaxis was associated with a decrease in symptomatic proximal or distal deep vein thrombosis (DVT) [relative risk (RR) = 0.52; 95% confidence interval (Cl): 0.35-0.77: p = 0.001; absolute risk reduction (ARR) = 0.32%, number needed to treat (NNT) = 313], and symptomatic non-fatal pulmonary embolism (RR = 0.61; 95% Cl 0.38-0.99: p = 0.04; ARR = 0.16%; NNT = 625), an increase in major bleeding (RR = 2.08; 95% Cl 1.50-2.90: p < 0.0001, absolute risk increase = 0.41%, number needed to harm = 244), and no significant reduction in VTE-related mortality (RR = 0.69; 95% Cl 0.45-1.06: p = 0.09) or all-cause mortality (RR = 1.00; 95% CI 0.89-1.12; p = 0.95). There was heterogeneity for major bleeding due to results from the APEX trial (no difference between betrixaban and enoxaparin). Compared with short-duration thromboprophylaxis, extended-duration treatment reduces the risk for symptomatic DVT and non-fatal pulmonary embolism. Extended treatment with apixaban, enoxaparin and rivaroxaban but not betrixaban increases the risk for major

  11. Role of nitric oxide synthase inhibition in the acute hypertensive response to intracerebroventricular cadmium

    PubMed Central

    Demontis, Maria Piera; Varoni, Maria Vittoria; Volpe, Anna Rita; Emanueli, Costanza; Madeddu, Paolo

    1998-01-01

    In the rat, intracerebroventricular (i.c.v.) injection of cadmium, a pollutant with long biological half-life, causes a sustained increase in blood pressure at doses that are ineffective by peripheral route. Since cadmium inhibits calcium-calmodulin constitutive nitric oxide (NO) synthase in cytosolic preparations of rat brain, this mechanism may be responsible for the acute pressor action of this heavy metal.To test this possibility, we evaluated the effect of i.c.v. injection of 88 nmol cadmium in normotensive unanaesthetized Wistar rats, which were i.c.v. pre-treated with: (1) saline (control), (2) L-arginine (L-Arg), to increase the availability of substrate for NO biosynthesis, (3) D-arginine (D-Arg), (4) 3-[4-morpholinyl]-sydnonimine-hydrochloride (SIN-1), an NO donor, or (5) CaCl2, a cofactor of brain calcium-calmodulin-dependent cNOSI. In additional experiments, the levels of L-citrulline (the stable equimolar product derived from enzymatic cleavage of L-Arg by NO synthase) were determined in the brain of vehicle- or cadmium-treated rats.The pressor response to cadmium reached its nadir at 5 min (43±4 mmHg) and lasted over 20 min in controls. L-Citrulline/protein content was reduced from 35 up to 50% in the cerebral cortex, pons, hippocampus, striatus, hypothalamus (P<0.01) of cadmium-treated rats compared with controls. Central injection of NG nitro-L-arginine-methylester (L-NAME) also reduced the levels of L-citrulline in the brain.Both the magnitude and duration of the response were attenuated by 1.21 and 2.42 μmol SIN-1 (32±3 and 15±4 mmHg, P<0.05), or 1 μmol CaCl2 (6±4 mmHg, P<0.05). Selectivity of action exerted by SIN-1 was confirmed by the use of another NO donor, S-nitroso-N-acetyl-penicillamine (SNAP). Both L-Arg and D-Arg caused a mild but significant attenuation in the main phase of the pressor response evoked by cadmium. However, only L-Arg reduced the magnitude of the delayed, pressor response. Despite their similarity in

  12. Inhalation of ambroxol inhibits cigarette smoke-induced acute lung injury in a mouse model by inhibiting the Erk pathway.

    PubMed

    Ge, Ling-tian; Liu, Ya-nan; Lin, Xi-xi; Shen, Hui-juan; Jia, Yong-liang; Dong, Xin-wei; Sun, Yun; Xie, Qiang-min

    2016-04-01

    Oral and injection administration of ambroxol has been clinically used to treat airway disease. However, little is known about its potentials in inhalation therapy. In present studies, we tested the effects of ambroxol by inhalation with intravenous administration, and explored the underlying working mechanism. The mice received 10 cigarettes exposure every day for 4 days. Inhaled solution of ambroxol was aerosolized 20 min before the exposure of cigarette smoke (CS). The effect of ambroxol on the expression of mucoprotein 5 AC (MUC5AC) and proinflammatory cytokines in NCI-H292 cells stimulated with cigarette smoke extract (CSE). Four days of daily inhalation of ambroxol at 3.75 or 7.5mg/ml for 20 min suppressed the accumulation of neutrophils and macrophages in the bronchoalveolar lavage fluid (BALF) and lung tissues, and inhibited increases in the mRNA and protein levels of tumor necrosis factor (TNF)-α, CCL-2 and KC, but not interleukin (IL)-1β in the CS-exposed mice. Moreover, ambroxol at 3.75 or 7.5mg/ml facilitated airway mucosa cilia clearance, reduced glycosaminoglycans level in BALF and MUC5AC mRNA levels in lung tissues. The effects of ambroxol by inhalation at 7.5mg/ml was comparable to that of ambroxol at 20mg/kg i.v. and dexamethasone at 0.5mg/kg i.p. Using cultured lung epithelial cells, we demonstrated that pretreatment with ambroxol at 2 or 20 μM inhibited the CSE-induced up-regulation of MUC5AC, TNF-α, IL-1β mRNA levels, which was through inhibiting Erk signaling pathway. Our results demonstrate the beneficial effects of ambroxol as an inhalation replace systemic administration for COPD therapy.

  13. [Methotrexate pharmacology].

    PubMed

    Lagarce, L; Zenut, M; Lainé-Cessac, P

    2015-03-01

    Methotrexate is a folic acid analog, which is a thymidylate synthetase and dihydrofolate reductase inhibitor. It is used in oncology, dermatology and rheumatology and off labelling in the treatment of ectopic pregnancies. This paper is a review of methotrexate pharmacology with focus on data concerning ectopic pregnancies.

  14. Central Agonism of GPR120 Acutely Inhibits Food Intake and Food Reward and Chronically Suppresses Anxiety-Like Behavior in Mice

    PubMed Central

    Fisette, Alexandre; Fernandes, Maria F.; Hryhorczuk, Cécile; Poitout, Vincent; Alquier, Thierry; Fulton, Stephanie

    2016-01-01

    Background: GPR120 (FFAR4) is a G-protein coupled receptor implicated in the development of obesity and the antiinflammatory and insulin-sensitizing effects of omega-3 (ω-3) polyunsaturated fatty acids. Increasing central ω-3 polyunsaturated fatty acid levels has been shown to have both anorectic and anxiolytic actions. Despite the strong clinical interest in GPR120, its role in the brain is largely unknown, and thus we sought to determine the impact of central GPR120 pharmacological activation on energy balance, food reward, and anxiety-like behavior. Methods: Male C57Bl/6 mice with intracerebroventricular cannulae received a single injection (0.1 or 1 µM) or continuous 2-week infusion (1 µM/d; mini-pump) of a GPR120 agonist or vehicle. Free-feeding intake, operant lever-pressing for palatable food, energy expenditure (indirect calorimetry), and body weight were measured. GPR120 mRNA expression was measured in pertinent brain areas. Anxiety-like behavior was assessed in the elevated-plus maze and open field test. Results: GPR120 agonist injections substantially reduced chow intake during 4 hours postinjection, suppressed the rewarding effects of high-fat/-sugar food, and blunted approach-avoidance behavior in the open field. Conversely, prolonged central GPR120 agonist infusions reduced anxiety-like behavior in the elevated-plus maze and open field, yet failed to affect free-feeding intake, energy expenditure, and body weight on a high-fat diet. Conclusion: Acute reductions in food intake and food reward suggest that GPR120 could mediate the effects of central ω-3 polyunsaturated fatty acids to inhibit appetite. The anxiolytic effect elicited by GPR120 agonist infusions favors the testing of compounds that can enter the brain to activate GPR120 for the mitigation of anxiety. PMID:26888796

  15. Pro-cognitive and antipsychotic efficacy of the alpha7 nicotinic partial agonist SSR180711 in pharmacological and neurodevelopmental latent inhibition models of schizophrenia.

    PubMed

    Barak, Segev; Arad, Michal; De Levie, Amaya; Black, Mark D; Griebel, Guy; Weiner, Ina

    2009-06-01

    Schizophrenia symptoms can be segregated into positive, negative and cognitive, which exhibit differential sensitivity to drug treatments. Accumulating evidence points to efficacy of alpha7 nicotinic receptor (nAChR) agonists for cognitive deficits in schizophrenia but their activity against positive symptoms is thought to be minimal. The present study examined potential pro-cognitive and antipsychotic activity of the novel selective alpha7 nAChR partial agonist SSR180711 using the latent inhibition (LI) model. LI is the reduced efficacy of a previously non-reinforced stimulus to gain behavioral control when paired with reinforcement, compared with a novel stimulus. Here, no-drug controls displayed LI if non-reinforced pre-exposure to a tone was followed by weak but not strong conditioning (2 vs 5 tone-shock pairings). MK801 (0.05 mg/kg, i.p.) -treated rats as well as rats neonatally treated with nitric oxide synthase inhibitor L-NoArg (10 mg/kg, s.c.) on postnatal days 4-5, persisted in displaying LI with strong conditioning, whereas amphetamine (1 mg/kg) -treated rats failed to show LI with weak conditioning. SSR180711 (0.3, 1, 3 mg/kg, i.p.) was able to alleviate abnormally persistent LI produced by acute MK801 and neonatal L-NoArg; these models are believed to model cognitive aspects of schizophrenia and activity here was consistent with previous findings with alpha7-nAChR agonists. In addition, unexpectedly, SSR180711 (1, 3 mg/kg, i.p.) potentiated LI with strong conditioning in no-drug controls and reversed amphetamine-induced LI disruption, two effects considered predictive of activity against positive symptoms of schizophrenia. These findings suggest that SSR180711 may be beneficial not only for the treatment of cognitive symptoms in schizophrenia, as reported multiple times previously, but also positive symptoms.

  16. Pharmacological inhibition of FAAH modulates TLR-induced neuroinflammation, but not sickness behaviour: An effect partially mediated by central TRPV1.

    PubMed

    Henry, Rebecca J; Kerr, Daniel M; Flannery, Lisa E; Killilea, Marykate; Hughes, Edel M; Corcoran, Louise; Finn, David P; Roche, Michelle

    2017-05-01

    Aberrant activation of toll-like receptors (TLRs), key components of the innate immune system, has been proposed to underlie and exacerbate a range of central nervous system disorders. Increasing evidence supports a role for the endocannabinoid system in modulating inflammatory responses including those mediated by TLRs, and thus this system may provide an important treatment target for neuroinflammatory disorders. However, the effect of modulating endocannabinoid tone on TLR-induced neuroinflammation in vivo and associated behavioural changes is largely unknown. The present study examined the effect of inhibiting fatty acid amide hydrolyase (FAAH), the primary enzyme responsible for the metabolism of anandamide (AEA), in vivo on TLR4-induced neuroimmune and behavioural responses, and evaluated sites and mechanisms of action. Systemic administration of the FAAH inhibitor PF3845 increased levels of AEA, and related FAAH substrates N-oleoylethanolamide (OEA) and N-palmitoylethanolamide (PEA), in the frontal cortex and hippocampus of rats, an effect associated with an attenuation in the expression of pro- and anti-inflammatory cytokines and mediators measured 2hrs following systemic administration of the TLR4 agonist, lipopolysaccharide (LPS). These effects were mimicked by central i.c.v. administration of PF3845, but not systemic administration of the peripherally-restricted FAAH inhibitor URB937. Central antagonism of TRPV1 significantly attenuated the PF3845-induced decrease in IL-6 expression, effects not observed following antagonism of CB1, CB2, PPARα, PPARγ or GPR55. LPS-induced a robust sickness-like behavioural response and increased the expression of markers of glial activity and pro-inflammatory cytokines over 24hrs. Systemic administration of PF3845 modulated the TLR4-induced expression of neuroimmune mediators and anhedonia without altering acute sickness behaviour. Overall, these findings support an important role for FAAH substrates directly within

  17. Activation of AMP-activated protein kinase, inhibition of pyruvate dehydrogenase activity, and redistribution of substrate partitioning mediate the acute insulin-sensitizing effects of troglitazone in skeletal muscle cells.

    PubMed

    Fediuc, S; Pimenta, A S; Gaidhu, M P; Ceddia, R B

    2008-05-01

    The aim of this study was to investigate the acute effects of troglitazone on several pathways of glucose and fatty acid (FA) partitioning and the molecular mechanisms involved in these processes in skeletal muscle. Exposure of L6 myotubes to troglitazone for 1 h significantly increased phosphorylation of AMPK and ACC, which was followed by approximately 30% and approximately 60% increases in palmitate oxidation and carnitine palmitoyl transferase-1 (CPT-1) activity, respectively. Troglitazone inhibited basal ( approximately 25%) and insulin-stimulated ( approximately 35%) palmitate uptake but significantly increased basal and insulin-stimulated glucose uptake by approximately 2.2- and 2.7-fold, respectively. Pharmacological inhibition of AMPK completely prevented the effects of troglitazone on palmitate oxidation and glucose uptake. Interestingly, even though troglitazone exerted an insulin sensitizing effect, it reduced basal and insulin-stimulated rates of glycogen synthesis, incorporation of glucose into lipids, and glucose oxidation to values corresponding to approximately 30%, approximately 60%, and 30% of the controls, respectively. These effects were accompanied by an increase in basal and insulin-stimulated phosphorylation of Akt(Thr308), Akt(Ser473), and GSK3alpha/beta. Troglitazone also powerfully suppressed pyruvate decarboxylation, which was followed by a significant increase in basal ( approximately 3.5-fold) and insulin-stimulated ( approximately 5.5-fold) rates of lactate production by muscle cells. In summary, we provide novel evidence that troglitazone exerts acute insulin sensitizing effects by increasing FA oxidation, reducing FA uptake, suppressing pyruvate dehydrogenase activity, and shifting glucose metabolism toward lactate production in muscle cells. These effects seem to be at least partially dependent on AMPK activation and may account for potential acute PPAR-gamma-independent anti-diabetic effects of thiazolidinediones in skeletal

  18. Inhibition of vascular endothelial growth factor signaling facilitates liver repair from acute ethanol-induced injury in zebrafish

    PubMed Central

    Zhang, Changwen; Ellis, Jillian L.

    2016-01-01

    ABSTRACT Alcoholic liver disease (ALD) results from alcohol overconsumption and is among the leading causes of liver-related morbidity and mortality worldwide. Elevated expression of vascular endothelial growth factor (VEGF) and its receptors has been observed in ALD, but how it contributes to ALD pathophysiology is unclear. Here, we investigated the impact of VEGF signaling inhibition on an established zebrafish model of acute alcoholic liver injury. Kdrl activity was blocked by chemical inhibitor treatment or by genetic mutation. Exposing 4-day-old zebrafish larvae to 2% ethanol for 24 h induced hepatic steatosis, angiogenesis and fibrogenesis. The liver started self-repair once ethanol was removed. Although inhibiting Kdrl did not block the initial activation of hepatic stellate cells during ethanol treatment, it suppressed their proliferation, extracellular matrix protein deposition and fibrogenic gene expression after ethanol exposure, thus enhancing the liver repair. It also ameliorated hepatic steatosis and attenuated hepatic angiogenesis that accelerated after the ethanol treatment. qPCR showed that hepatic stellate cells are the first liver cell type to increase the expression of VEGF ligand and receptor genes in response to ethanol exposure. Both hepatic stellate cells and endothelial cells, but not hepatic parenchymal cells, expressed kdrl upon ethanol exposure and were likely the direct targets of Kdrl inhibition. Ethanol-induced steatosis and fibrogenesis still occurred in cloche mutants that have hepatic stellate cells but lack hepatic endothelial cells, and Kdrl inhibition suppressed both phenotypes in the mutants. These results suggest that VEGF signaling mediates interactions between activated hepatic stellate cells and hepatocytes that lead to steatosis. Our study demonstrates the involvement of VEGF signaling in regulating sustained liver injuries after acute alcohol exposure. It also provides a proof of principle of using the zebrafish model

  19. Golgi tendon organ reflex inhibition following manually applied acute static stretching.

    PubMed

    Miller, Kevin C; Burne, John A

    2014-01-01

    Golgi tendon organ disinhibition may contribute to exercise-associated muscle cramp (henceforth referred to as "cramps") genesis. Static stretching pre-exercise is prescribed to prevent cramps based on the assumption golgi tendon organ inhibition remains elevated post-stretching. We determined whether stretching increased gastrocnemius golgi tendon organ inhibition and, if so, the time course of this inhibition post-stretching. Twelve participants' dominant limb medial gastrocnemius inhibition was measured before, and at 1, 5, 10, 15 and 30 min after investigators applied three, 1-min duration stretches. Participants maintained voluntary contraction intensities of 5% of their maximum while the Achilles tendon was stimulated transcutaneously 50 times. Five-hundred millisecond epochs of raw electromyographic activity were band-pass filtered, full-wave rectified and averaged. An algorithm identified inhibitory points and calculated the area, maximum and duration of inhibition. Area of inhibition (F1,14 = 1.5, P = 0.25), maximum inhibition (F1,14 = 0.2, P = 0.72) and duration of inhibition (F1,14 = 1.5, P = 0.24) were unaffected by static stretching over the 30-min post-stretching period. If pre-stretching does prevent fatigue-induced cramping, the mechanism is unlikely to involve the autoinhibition produced by the golgi tendon organ reflex. Further empirical research is needed to validate the proposed link between static stretching and cramping and then to investigate alternative mechanisms.

  20. 2,4-dinitrophenol acutely inhibits rabbit atrial Ca2+ -sensitive Cl- current (I(TO2)).

    PubMed

    Ravesloot, J H; Rombouts, E

    2000-10-01

    We investigated the effects of 2,4-dinitrophenol (DNP), the uncoupler of mitochondrial oxidative phosphorylation, on the Ca2+ -sensitive Cl- current component of the transient outward current (I(TO2)). Amphotericin B perforated-patch, whole-cell patch-clamp technique was employed (35 degrees C) using enzymatically isolated single rabbit atrial myocytes. We defined I(TO2) as the amplitude of the 2 mM 4-aminopyridine resistant transient outward current sensitive to anthracene-9-carboxylic acid (A9C). Between +5 and +45 mV, 0.2 mM A9C inhibited I(TO2) by approximately 70% (n = 13). Within 30 s after application of 0.2 mM DNP, both normal I(TO2) transients (n = 8) and the I(TO2) transients that remained after A9C treatment (n = 8) were inhibited completely. In cells expressing I(TO2) (70% of total), DNP also suppressed an A9C-insensitive slow outward current by approximately 40%, but the holding current at -80 mV was unaffected. There was a approximately 2 min latency between inhibitory effects of DNP and subsequent membrane current increase, presumably caused by activation of the ATP-sensitive K+ channels (n = 16). We conclude that DNP acutely inhibits I(TO2) via a mechanism presumably separate from metabolic inhibition.

  1. Acute Lymphoblastic Leukemia Cells Inhibit the Differentiation of Bone Mesenchymal Stem Cells into Osteoblasts In Vitro by Activating Notch Signaling

    PubMed Central

    Yang, Gui-Cun; Xu, You-Hua; Chen, Hong-Xia; Wang, Xiao-Jing

    2015-01-01

    The disruption of normal hematopoiesis has been observed in leukemia, but the mechanism is unclear. Osteoblasts originate from bone mesenchymal stem cells (BMSCs) and can maintain normal hematopoiesis. To investigate how leukemic cells inhibit the osteogenic differentiation of BMSCs and the role of Notch signaling in this process, we cocultured BMSCs with acute lymphoblastic leukemia (ALL) cells in osteogenic induction medium. The expression levels of Notch1, Hes1, and the osteogenic markers Runx2, Osteopontin (OPN), and Osteocalcin (OCN) were assessed by real-time RT-PCR and western blotting on day 3. Alkaline phosphatase (ALP) activity was analyzed using an ALP kit, and mineralization deposits were detected by Alizarin red S staining on day 14. And then we treated BMSCs with Jagged1 and anti-Jagged1 neutralizing Ab. The expression of Notch1, Hes1, and the abovementioned osteogenic differentiation markers was measured. Inhibition of the expression of Runx2, OPN, and OCN and reduction of ALP activity and mineralization deposits were observed in BMSCs cocultured with ALL cells, while Notch signal inhibiting rescued these effects. All these results indicated that ALL cells could inhibit the osteogenic differentiation of BMSCs by activating Notch signaling, resulting in a decreased number of osteoblastic cells, which may impair normal hematopoiesis. PMID:26339248

  2. Quercetin Inhibits Peripheral and Spinal Cord Nociceptive Mechanisms to Reduce Intense Acute Swimming-Induced Muscle Pain in Mice

    PubMed Central

    Borghi, Sergio M.; Pinho-Ribeiro, Felipe A.; Fattori, Victor; Bussmann, Allan J. C.; Vignoli, Josiane A.; Camilios-Neto, Doumit; Casagrande, Rubia; Verri, Waldiceu A.

    2016-01-01

    The present study aimed to evaluate the effects of the flavonoid quercetin (3,3´,4´,5,7-pentahydroxyflavone) in a mice model of intense acute swimming-induced muscle pain, which resembles delayed onset muscle soreness. Quercetin intraperitoneal (i.p.) treatment dose-dependently reduced muscle mechanical hyperalgesia. Quercetin inhibited myeloperoxidase (MPO) and N-acetyl-β-D- glucosaminidase (NAG) activities, cytokine production, oxidative stress, cyclooxygenase-2 (COX-2) and gp91phox mRNA expression and muscle injury (creatinine kinase [CK] blood levels and myoblast determination protein [MyoD] mRNA expression) as well as inhibited NFκB activation and induced Nrf2 and HO-1 mRNA expression in the soleus muscle. Beyond inhibiting those peripheral effects, quercetin also inhibited spinal cord cytokine production, oxidative stress and glial cells activation (glial fibrillary acidic protein [GFAP] and ionized calcium-binding adapter molecule 1 [Iba-1] mRNA expression). Concluding, the present data demonstrate that quercetin is a potential molecule for the treatment of muscle pain conditions related to unaccustomed exercise. PMID:27583449

  3. ABT-869, a multitargeted receptor tyrosine kinase inhibitor: inhibition of FLT3 phosphorylation and signaling in acute myeloid leukemia.

    PubMed

    Shankar, Deepa B; Li, Junling; Tapang, Paul; Owen McCall, J; Pease, Lori J; Dai, Yujia; Wei, Ru-Qi; Albert, Daniel H; Bouska, Jennifer J; Osterling, Donald J; Guo, Jun; Marcotte, Patrick A; Johnson, Eric F; Soni, Niru; Hartandi, Kresna; Michaelides, Michael R; Davidsen, Steven K; Priceman, Saul J; Chang, Jenny C; Rhodes, Katrin; Shah, Neil; Moore, Theodore B; Sakamoto, Kathleen M; Glaser, Keith B

    2007-04-15

    In 15% to 30% of patients with acute myeloid leukemia (AML), aberrant proliferation is a consequence of a juxtamembrane mutation in the FLT3 gene (FMS-like tyrosine kinase 3-internal tandem duplication [FLT3-ITD]), causing constitutive kinase activity. ABT-869 (a multitargeted receptor tyrosine kinase inhibitor) inhibited the phosphorylation of FLT3, STAT5, and ERK, as well as Pim-1 expression in MV-4-11 and MOLM-13 cells (IC(50) approximately 1-10 nM) harboring the FLT3-ITD. ABT-869 inhibited the proliferation of these cells (IC(50) = 4 and 6 nM, respectively) through the induction of apoptosis (increased sub-G(0)/G(1) phase, caspase activation, and PARP cleavage), whereas cells harboring wild-type (wt)-FLT3 were less sensitive. In normal human blood spiked with AML cells, ABT-869 inhibited phosphorylation of FLT3 (IC(50) approximately 100 nM), STAT5, and ERK, and decreased Pim-1 expression. In methylcellulose-based colony-forming assays, ABT-869 had no significant effect up to 1000 nM on normal hematopoietic progenitor cells, whereas in AML patient samples harboring both FLT3-ITD and wt-FLT3, ABT-869 inhibited colony formation (IC(50) = 100 and 1000 nM, respectively). ABT-869 dose-dependently inhibited MV-4-11 and MOLM-13 flank tumor growth, prevented tumor formation, regressed established MV-4-11 xenografts, and increased survival by 20 weeks in an MV-4-11 engraftment model. In tumors, ABT-869 inhibited FLT3 phosphorylation, induced apoptosis (transferase-mediated dUTP nick-end labeling [TUNEL]) and decreased proliferation (Ki67). ABT-869 is under clinical development for AML.

  4. Pharmacologic vitreolysis.

    PubMed

    Rhéaume, Marc-André; Vavvas, Demetrios

    2010-01-01

    It is now well recognized that vitreous plays an important role in the pathogenesis of various retinal disorders. In many instances it can be addressed with pars plana vitrectomy, although this approach, like any surgery, has its limitations. The search for alternatives or adjunct to surgery has led to the development of pharmacologic vitreolysis. The use of intravitreal agents to alter the vitreous in order to reduce or eliminate its role in disease seems promising. The purpose of this article is to summarize the present knowledge on pharmacologic vitreolysis. A review of the different agents used and of ongoing trials will be presented. Also, current understanding of vitreous structure and its interaction with the retina will be discussed.

  5. The role of FOXO and PPAR transcription factors in diet-mediated inhibition of PDC activation and carbohydrate oxidation during exercise in humans and the role of pharmacological activation of PDC in overriding these changes.

    PubMed

    Constantin-Teodosiu, Dumitru; Constantin, Despina; Stephens, Francis; Laithwaite, David; Greenhaff, Paul L

    2012-05-01

    High-fat feeding inhibits pyruvate dehydrogenase complex (PDC)-controlled carbohydrate (CHO) oxidation, which contributes to muscle insulin resistance. We aimed to reveal molecular changes underpinning this process in resting and exercising humans. We also tested whether pharmacological activation of PDC overrides these diet-induced changes. Healthy males consumed a control diet (CD) and on two further occasions an isocaloric high-fat diet (HFD). After each diet, subjects cycled for 60 min after intravenous infusion with saline (CD and HFD) or dichloroacetate (HFD+DCA). Quadriceps muscle biopsies obtained before and after 10 and 60 min of exercise were used to estimate CHO use, PDC activation, and mRNAs associated with insulin, fat, and CHO signaling. Compared with CD, HFD increased resting pyruvate dehydrogenase kinase 2 (PDK2), PDK4, forkhead box class O transcription factor 1 (FOXO1), and peroxisome proliferator-activated receptor transcription factor α (PPARα) mRNA and reduced PDC activation. Exercise increased PDC activation and whole-body CHO use in HFD, but to a lower extent than in CD. Meanwhile PDK4 and FOXO1, but not PPARα or PDK2, mRNA remained elevated. HFD+DCA activated PDC throughout and restored whole-body CHO use during exercise. FOXO1 appears to play a role in HFD-mediated muscle PDK4 upregulation and inhibition of PDC and CHO oxidation in humans. Also, pharmacological activation of PDC restores HFD-mediated inhibition of CHO oxidation during exercise.

  6. Inhibition of the NLRP3 inflammasome reduces the severity of experimentally-induced acute pancreatitis in obese mice

    PubMed Central

    York, Jason M; Castellanos, Karla J; Cabay, Robert J; Fantuzzi, Giamila

    2014-01-01

    Acute pancreatitis (AP), while most often a mild and self-limiting inflammatory disease, worsens to a characteristically necrotic severe acute pancreatitis (SAP) in about 20% of cases. Obesity, affecting more than a third of American adults, is a risk factor for the development of SAP, but the exact mechanism of this association has not been identified. Coincidental with chronic low-grade inflammation, activation of the NLRP3 inflammasome increases with obesity. Lean mice genetically deficient for specific components of the NLRP3 inflammasome are protected from experimentally-induced AP, indicating a direct involvement of this pathway in AP pathophysiology. We hypothesized that inhibition of the NLRP3 inflammasome with the sulfonylurea drug glyburide would reduce disease severity in obese mice with cerulein-induced SAP. Treatment with glyburide led to significantly reduced relative pancreatic mass and water content and less pancreatic damage and cell death in genetically obese ob/ob mice with SAP compared to vehicle-treated obese SAP mice. Glyburide administration in ob/ob mice with cerulein induced SAP also resulted in significantly reduced serum levels of interleukin-6, lipase and amylase, and led to lower production of LPS-stimulated IL-1β release in cultured peritoneal cells, compared to vehicle treated ob/ob mice with SAP. Together, these data indicate involvement of the NLRP3 inflammasome in obesity-associated SAP, and expose the possible utility of its inhibition in prevention or treatment of SAP in obese individuals. PMID:25152324

  7. Targeting BET proteins improves the therapeutic efficacy of BCL-2 inhibition in T-cell acute lymphoblastic leukemia.

    PubMed

    Peirs, S; Frismantas, V; Matthijssens, F; Van Loocke, W; Pieters, T; Vandamme, N; Lintermans, B; Dobay, M P; Berx, G; Poppe, B; Goossens, S; Bornhauser, B C; Bourquin, J-P; Van Vlierberghe, P

    2017-02-03

    Inhibition of anti-apoptotic BCL-2 (B-cell lymphoma 2) has recently emerged as a promising new therapeutic strategy for the treatment of a variety of human cancers, including leukemia. Here, we used T-cell acute lymphoblastic leukemia (T-ALL) as a model system to identify novel synergistic drug combinations with the BH3 mimetic venetoclax (ABT-199). In vitro drug screening in primary leukemia specimens that were derived from patients with high risk of relapse or relapse and cell lines revealed synergistic activity between venetoclax and the BET (bromodomain and extraterminal) bromodomain inhibitor JQ1. Notably, this drug synergism was confirmed in vivo using T-ALL cell line and patient-derived xenograft models. Moreover, the therapeutic benefit of this drug combination might, at least in part, be mediated by an acute induction of the pro-apoptotic factor BCL2L11 and concomitant reduction of BCL-2 upon BET bromodomain inhibition, ultimately resulting in an enhanced binding of BIM (encoded by BCL2L11) to BCL-2. Altogether, our work provides a rationale to develop a new type of targeted combination therapy for selected subgroups of high-risk leukemia patients.Leukemia advance online publication, 3 February 2017; doi:10.1038/leu.2017.10.

  8. [Sodium butyrate inhibits HMGB1 expression and release and attenuates concanavalin A-induced acute liver injury in mice].

    PubMed

    Gong, Quan; Chen, Mao-Jian; Wang, Chao; Nie, Hao; Zhang, Yan-Xiang; Shu, Ke-Gang; Li, Gang

    2014-10-25

    The purpose of the present study is to explore the protective effects of sodium butyrate (SB) pretreatment on concanavalin A (Con A)-induced acute liver injury in mice. The model animals were first administered intraperitoneally with SB. Half an hour later, acute liver injury mouse model was established by caudal vein injection with Con A (15 mg/kg). Then, levels of serous alanine aminotransferase (ALT) and aspartate aminotransferase (AST) were measured using standard clinical method by an automated chemistry analyzer, tumor necrosis factor-α (TNF-α) and interferon-γ (IFN-γ) were measured by ELISA, and pathological changes in hepatic tissue were observed by using HE staining and light microscopy. The expression and release of high-mobility group box 1 (HMGB1) were assessed by using reverse transcription polymerase chain reaction (RT-PCR), immunohistochemistry and ELISA. The results showed that the pretreatment of SB significantly protected Con A-treated mice from liver injury as evidenced by the decrease of serum ALT, AST (P < 0.01) and reduction of hepatic tissues necrosis. SB also decreased levels of serous TNF-α and IFN-γ (P < 0.01). Furthermore, the expression and release of HMGB1 were markedly inhibited by SB pretreatment (P < 0.05 or P < 0.01). These results suggest that the attenuating effect of SB on Con A-induced acute liver injury may be due to its role of reducing the TNF-α and IFN-γ production, and inhibiting HMGB1 expression and release.

  9. CFTR pharmacology.

    PubMed

    Zegarra-Moran, Olga; Galietta, Luis J V

    2017-01-01

    CFTR protein is an ion channel regulated by cAMP-dependent phosphorylation and expressed in many types of epithelial cells. CFTR-mediated chloride and bicarbonate secretion play an important role in the respiratory and gastrointestinal systems. Pharmacological modulators of CFTR represent promising drugs for a variety of diseases. In particular, correctors and potentiators may restore the activity of CFTR in cystic fibrosis patients. Potentiators are also potentially useful to improve mucociliary clearance in patients with chronic obstructive pulmonary disease. On the other hand, CFTR inhibitors may be useful to block fluid and electrolyte loss in secretory diarrhea and slow down the progression of polycystic kidney disease.

  10. The role of serotonin in reward, punishment and behavioural inhibition in humans: insights from studies with acute tryptophan depletion.

    PubMed

    Faulkner, Paul; Deakin, J F William

    2014-10-01

    Deakin and Graeff proposed that forebrain 5-hydroxytryptamine (5-HT) projections are activated by aversive events and mediate anticipatory coping responses including avoidance learning and suppression of the fight-flight escape/panic response. Other theories proposed 5-HT mediates aspects of behavioural inhibition or reward. Most of the evidence comes from rodent studies. We review 36 experimental studies in humans in which the technique of acute tryptophan depletion (ATD) was used to explicitly address the role of 5-HT in response inhibition, punishment and reward. ATD did not cause disinhibition of responding in the absence of rewards or punishments (9 studies). A major role for 5-HT in reward processing is unlikely but further tests are warranted by some ATD findings. Remarkably, ATD lessened the ability of punishments (losing points or notional money) to restrain behaviour without affecting reward processing in 7 studies. Two of these studies strongly indicate that ATD blocks 5-HT mediated aversively conditioned Pavlovian inhibition and this can explain a number of the behavioural effects of ATD.

  11. SphK1 inhibitor II (SKI-II) inhibits acute myelogenous leukemia cell growth in vitro and in vivo.

    PubMed

    Yang, Li; Weng, Wei; Sun, Zhi-Xin; Fu, Xian-Jie; Ma, Jun; Zhuang, Wen-Fang

    2015-05-15

    Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, and concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent.

  12. A review on advantages of implementing luminescence inhibition test (Vibrio fischeri) for acute toxicity prediction of chemicals.

    PubMed

    Parvez, Shahid; Venkataraman, Chandra; Mukherji, Suparna

    2006-02-01

    Evaluation of biological effects using a rapid, sensitive and cost effective method can indicate specific information on toxicity/ecotoxicity. Since assays based on animals, plants and algae are expensive, time consuming and require large sample volume, recent studies have emphasized the benefits of rapid, reproducible and cost effective bacterial assays for toxicity screening and assessment. This review focuses on a bacterial assay, i.e., Vibrio fischeri bioluminescence inhibition assay, which is often chosen as the first test in a test battery based on speed and cost consideration. The test protocol is simple and was originally applied for aqueous phase samples or extracts. The versatility of the assay has increased with subsequent modification, i.e., the kinetic assay for turbid and colored samples and the solid phase test for analyzing sediment toxicity. Researchers have reported the Vibrio fischeri bioluminescence assay as the most sensitive across a wide range of chemicals compared to other bacterial assays such as nitrification inhibition, respirometry, ATP luminescence and enzyme inhibition. This assay shows good correlations with other standard acute toxicity assays and is reported to detect toxicity across a wide spectrum of toxicants.

  13. Cooperative and acute inhibition by multiple C-terminal motifs of L-type Ca2+ channels

    PubMed Central

    Liu, Nan; Yang, Yaxiong; Ge, Lin; Liu, Min; Colecraft, Henry M; Liu, Xiaodong

    2017-01-01

    Inhibitions and antagonists of L-type Ca2+ channels are important to both research and therapeutics. Here, we report C-terminus mediated inhibition (CMI) for CaV1.3 that multiple motifs coordinate to tune down Ca2+ current and Ca2+ influx toward the lower limits determined by end-stage CDI (Ca2+-dependent inactivation). Among IQV (preIQ3-IQ domain), PCRD and DCRD (proximal or distal C-terminal regulatory domain), spatial closeness of any two modules, e.g., by constitutive fusion, facilitates the trio to form the complex, compete against calmodulin, and alter the gating. Acute CMI by rapamycin-inducible heterodimerization helps reconcile the concurrent activation/inactivation attenuations to ensure Ca2+ influx is reduced, in that Ca2+ current activated by depolarization is potently (~65%) inhibited at the peak (full activation), but not later on (end-stage inactivation, ~300 ms). Meanwhile, CMI provides a new paradigm to develop CaV1 inhibitors, the therapeutic potential of which is implied by computational modeling of CaV1.3 dysregulations related to Parkinson’s disease. DOI: http://dx.doi.org/10.7554/eLife.21989.001 PMID:28059704

  14. Inhibition effect of glyphosate on the acute and subacute toxicity of cadmium to earthworm Eisenia fetida.

    PubMed

    Zhou, Chui-Fan; Wang, Yu-Jun; Sun, Rui-Juan; Liu, Cun; Fan, Guang-Ping; Qin, Wen-Xiu; Li, Cheng-Cheng; Zhou, Dong-Mei

    2014-10-01

    The acute and subacute toxicities of cadmium (Cd) to earthworm Eisenia fetida in the presence and absence of glyphosate were studied. Although Cd is highly toxic to E. fetida, the presence of glyphosate markedly reduced the acute toxicity of Cd to earthworm; both the mortality rate of the earthworms and the accumulation of Cd decreased with the increase of the glyphosate/Cd molar ratio. The subcellular distribution of Cd in E. fetida tissues showed that internal Cd was dominant in the intact cells fraction and the heat-stable proteins fraction. The presence of glyphosate reduced the concentration of Cd in all fractions, especially the intact cells. During a longer period of exposure, the weight loss of earthworm and the total Cd absorption was alleviated by glyphosate. Thus, the herbicide glyphosate can reduce the toxicity and bioavailability of Cd in the soil ecosystems at both short- and long-term exposures.

  15. 5-Aminosalicylic Acid Inhibits Acute Clostridium difficile Toxin A-Induced Colitis in Rats

    PubMed Central

    Vigna, Steven R.

    2014-01-01

    We tested the hypothesis that 5-aminosalicylic acid (5-ASA) inhibits toxin A-induced generation of colonic leukotriene B4 (LTB4) and toxin A colitis in rats. Isolated colonic segments in anesthetized rats were treated intraluminally with toxin A for 3 hours with or without 30 minutes of pretreatment with either 5-ASA or sulfapyridine and then colonic tissue levels of LTB4 were measured and inflammation was assessed. Separately, sulfasalazine was administered to rats in their drinking water for 5 days, isolated colonic segments were then prepared, toxin A was administered, and inflammation was assessed as before. Pretreatment with 5-ASA inhibited toxin A-induced increased tissue LTB4 concentration in the colon. Sulfasalazine and 5-ASA but not sulfapyridine significantly inhibited toxin A colitis. However, pretreatment with 5-ASA did not protect against direct TRPV1-mediated colitis caused by capsaicin. Toxin A stimulated the release of substance P (SP), and this effect was also inhibited by sulfasalazine and 5-ASA but not by sulfapyridine. Thus, toxin A stimulates colonic LTB4 resulting in activation of TRPV1, release of SP, and colitis. Inhibition of 5-LO by 5-ASA disrupts this pathway and supports the concept that LTB4 activation of TRPV1 plays a role in toxin A colitis. PMID:25045574

  16. 5-Aminosalicylic Acid Inhibits Acute Clostridium difficile Toxin A-Induced Colitis in Rats.

    PubMed

    Vigna, Steven R

    2014-01-01

    We tested the hypothesis that 5-aminosalicylic acid (5-ASA) inhibits toxin A-induced generation of colonic leukotriene B4 (LTB4) and toxin A colitis in rats. Isolated colonic segments in anesthetized rats were treated intraluminally with toxin A for 3 hours with or without 30 minutes of pretreatment with either 5-ASA or sulfapyridine and then colonic tissue levels of LTB4 were measured and inflammation was assessed. Separately, sulfasalazine was administered to rats in their drinking water for 5 days, isolated colonic segments were then prepared, toxin A was administered, and inflammation was assessed as before. Pretreatment with 5-ASA inhibited toxin A-induced increased tissue LTB4 concentration in the colon. Sulfasalazine and 5-ASA but not sulfapyridine significantly inhibited toxin A colitis. However, pretreatment with 5-ASA did not protect against direct TRPV1-mediated colitis caused by capsaicin. Toxin A stimulated the release of substance P (SP), and this effect was also inhibited by sulfasalazine and 5-ASA but not by sulfapyridine. Thus, toxin A stimulates colonic LTB4 resulting in activation of TRPV1, release of SP, and colitis. Inhibition of 5-LO by 5-ASA disrupts this pathway and supports the concept that LTB4 activation of TRPV1 plays a role in toxin A colitis.

  17. Kefir induces apoptosis and inhibits cell proliferation in human acute erythroleukemia.

    PubMed

    Jalali, Fatemeh; Sharifi, Mohammadreza; Salehi, Rasoul

    2016-01-01

    Acute erythroleukemia is an uncommon subtype of acute myeloid leukemia which has been considered to be a subtype of AML with a worse prognosis. Intensive chemotherapy is the first line of treatment. In recent years, the effect of kefir on some malignancies has been experimented. Kefir is a kind of beverage, which obtained by incubation of kefir grains with raw milk. Kefir grains are a symbiotic complex of different kinds of yeasts and bacteria, especially lactic acid bacteria which gather in a mostly carbohydrate matrix, named kefiran. We investigated the effect of kefir on acute erythroleukemia cell line (KG-1) and peripheral blood mononuclear cells (PBMCs). The cell line and PBMCs were treated with different doses of kefir and milk and incubated for three different times. We used Polymixin B to block the lipopolysaccharide and NaOH (1 mol/l) to neutralize the acidic media. Viability was detected by MTT assay. Apoptosis and necrosis were assessed by annexin-propidium iodide staining. Our results showed that kefir induced apoptosis and necrosis in KG-1 cell line. It was revealed that kefir decreased proliferation in erythroleukemia cell line. We did not observe a remarkable effect of kefir on PBMCs. Our study suggested that kefir may have potential to be an effective treatment for erythroleukemia.

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

    PubMed Central

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

    2016-01-01

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

  19. Some recent pharmacological findings with nitrendipine

    SciTech Connect

    Scriabine, A.; Anderson, C.L.; Janis, R.A.; Kojima, K.; Rasmussen, H.; Lee, S.; Michal, U.

    1984-01-01

    The available evidence indicates that nitrendipine and other dihydropyridines with a similar pharmacological action exert their therapeutic effects by inhibiting Ca/sup 2 +/ channels. In recent experiments, nitrendipine was shown to block K+-stimulated /sup 45/Ca/sup 2 +/ uptake and K+-induced contractions of isolated rabbit aortic rings. Its IC/sub 50/ were 4.7 and 8.9 nM for inhibition of Ca/sup 2 +/ uptake and of contractions, respectively. At higher concentrations, nitrendipine also reduced norepinephrine-induced /sup 45/Ca/sup 2 +/ uptake and norepinephrine-induced contractions of rabbit aortic strips. The norepinephrine-induced contractions were only slightly (21%) reduced by nitrendipine at 10 microM. Nitrendipine at 10 nM and higher concentrations inhibited K+- or angiotensin-II-(AII) induced release of aldosterone from isolated bovine adrenal glomerulosa cells. Dantrolene, 25 microM, enhanced the inhibitory activity of nitrendipine on AII-stimulated aldosterone release. Acute renal failure produced by either glycerol or gentamicin in rats was antagonized by nitrendipine at oral doses of 15-25 mg/kg/day. The studies confirmed previously reported observations that the usefulness of nitrendipine in the treatment of hypertension may be determined not only by its vasodilator action.

  20. Pharmacologic agents targeting autophagy

    PubMed Central

    Vakifahmetoglu-Norberg, Helin; Xia, Hong-guang; Yuan, Junying

    2015-01-01

    Autophagy is an important intracellular catabolic mechanism critically involved in regulating tissue homeostasis. The implication of autophagy in human diseases and the need to understand its regulatory mechanisms in mammalian cells have stimulated research efforts that led to the development of high-throughput screening protocols and small-molecule modulators that can activate or inhibit autophagy. Herein we review the current landscape in the development of screening technology as well as the molecules and pharmacologic agents targeting the regulatory mechanisms of autophagy. We also evaluate the potential therapeutic application of these compounds in different human pathologies. PMID:25654545

  1. Intracellular Hmgb1 Inhibits Inflammatory Nucleosome Release and Limits Acute Pancreatitis in Mice

    PubMed Central

    Kang, Rui; Zhang, Qiuhong; Hou, Wen; Yan, Zhenwen; Chen, Ruochan; Bonaroti, Jillian; Bansal, Preeti; Billiar, Timothy R.; Tsung, Allan; Wang, Qingde; Bartlett, David L.; Whitcomb, David C; Chang, Eugene B.; Zhu, Xiaorong; Wang, Haichao; Lu, Ben; Tracey, Kevin J.; Cao, Lizhi; Fan, Xue-Gong; Lotze, Michael T.; Zeh, Herbert J.; Tang, Daolin

    2014-01-01

    BACKGROUND & AIMS: High mobility group box 1 (HMGB1) is an abundant protein that regulates chromosome architecture and also functions as a damage-associated molecular pattern molecule. Little is known about its intracellular roles in response to tissue injury or during subsequent local and systemic inflammatory responses. We investigated the function of Hmgb1 in mice following induction of acute pancreatitis. METHODS: We utilized a Cre/LoxP system to create mice with pancreas-specific disruption in Hmbg1 (Pdx1-Cre; HMGB1flox/flox mice). Acute pancreatitis was induced in these mice (HMGB1flox/flox mice served as controls) following injection of L-arginine or cerulein. Pancreatic tissues and acinar cells were collected and analyzed by histologic, immunoblot, and immunohistochemical analyses. RESULTS: Following injection of L-arginine or cerulein, Pdx1-Cre; HMGB1flox/flox mice developed acute pancreatitis more rapidly than controls, with increased mortality. Pancreatic tissues of these mice also had higher levels of serum amylase, acinar cell death, leukocyte infiltration, and interstitial edema than controls. Pancreatic tissues and acinar cells collected from the Pdx1-Cre; HMGB1flox/flox mice following L-arginine- or cerulein injection demonstrated nuclear catastrophe with greater nucleosome release when compared with controls, along with increased phosphorylation/activation of RELA Nfκb, degradation of Iκb, and phosphorylation of Mapk. Inhibitors of reactive oxygen species (N-acetyl-L-cysteine) blocked L-arginine–induced DNA damage, necrosis, apoptosis, release of nucleosomes, and activation of Nfκb in pancreatic tissues and acinar cells from Pdx1-Cre; HMGB1flox/flox and control mice. Exogenous genomic DNA and recombinant histone H3 proteins significantly induced release of HMGB1 from mouse macrophages; administration of antibodies against H3 to mice reduced serum levels of HMGB1 and increased survival following L-arginine injection. CONCLUSIONS: In 2 mouse

  2. BCL2 Inhibition by Venetoclax: Targeting the Achilles' Heel of the Acute Myeloid Leukemia Stem Cell?

    PubMed

    Pullarkat, Vinod A; Newman, Edward M

    2016-10-01

    Venetoclax is an oral drug with an excellent side-effect profile that has the potential to revolutionize acute myeloid leukemia (AML) therapy in two areas. Venetoclax-based combination therapies could be a bridge to hematopoietic cell transplant with curative intent for patients with refractory/relapsed AML, and venetoclax-based therapy could provide meaningful survival prolongation for older patients with AML who are not candidates for more aggressive therapies. Cancer Discov; 6(10); 1082-3. ©2016 AACR.See related article by Konopleva and colleagues, p. 1106.

  3. Activation of the IL-1 gene in UV-irradiated mouse skin: association with inflammatory sequelae and pharmacologic intervention.

    PubMed

    Griswold, D E; Connor, J R; Dalton, B J; Lee, J C; Simon, P; Hillegass, L; Sieg, D J; Hanna, N

    1991-12-01

    The relationship between ultraviolet irradiation, interleukin-1 production, and inflammatory sequelae and the pharmacologic inhibition of these events was investigated in Balb/c mice exposed to ultraviolet irradiation from a bank of six Westinghouse FS40 sunlamps. The resulting edema (66% increase), inflammatory cell infiltration, and rise in the acute-phase reactant (fourfold) serum amyloid P component was preceded by the activation of the interleukin-1 beta gene and enhanced product formation. Administration of dexamethasone, which is known to inhibit interleukin-1 production, inhibited the inflammatory response to ultraviolet irradiation. Thus, production of interleukin-1 may be one of the initial events leading to the consequences of ultraviolet irradiation exposure.

  4. Induction or inhibition of cytochrome P450 2E1 modifies the acute toxicity of acrylonitrile in rats: biochemical evidence.

    PubMed

    Suhua, Wang; Rongzhu, Lu; Wenrong, Xu; Guangwei, Xing; Xiaowu, Zhao; Shizhong, Wang; Ye, Zhang; Fangan, Han; Aschner, Michael

    2010-06-01

    The present study was designed to examine the effects of the inhibition or induction of CYP2E1 activity on acute acrylonitrile (AN) toxicity in rats. Increased or decreased hepatic CYP2E1 activity was achieved by pretreatment with acetone or trans-1,2-dichloroethylene (DCE), respectively. AN (50 mg/kg) was administered by intraperitoneal injection. Onset of convulsions and death were observed in rats with increased CYP2E1 activity, whereas convulsions and death did not appear in rats within 1 h after treatment with AN alone. Convulsions occurred in all AN-treated animals with increased CYP2E1 activity at approximately 18 min. The levels of cyanide (CN(-)), a terminal metabolite of AN, were significantly increased in the brains and livers of the AN-treated rats with increased CYP2E1 activity, compared with the levels in rats treated with AN alone, DCE + AN or acetone + DCE + AN. The cytochrome c oxidase (CcOx) activities in the brains and livers of the rats treated with AN or AN + acetone were significantly lower than those in the normal control rats and the rats treated with DCE, whereas the CcOx activities in the brains and livers of rats with decreased CYP2E1 activity were significantly higher than those in AN-treated rats. Brain lipid peroxidation was enhanced, and the antioxidant capacity was significantly compromised in rats with decreased CYP2E1 activity compared with rats with normal or increased CYP2E1 activity. Therefore, inhibition of CYP2E1 and simultaneous antioxidant therapy should be considered as supplementary therapeutic interventions in acute AN intoxication cases with higher CYP2E1 activity, thus a longer window of opportunity would be got to offer further emergency medication.

  5. Protective Effects of Dioscin against Lipopolysaccharide-Induced Acute Lung Injury through Inhibition of Oxidative Stress and Inflammation

    PubMed Central

    Yao, Hong; Sun, Yiping; Song, Shasha; Qi, Yan; Tao, Xufeng; Xu, Lina; Yin, Lianhong; Han, Xu; Xu, Youwei; Li, Hua; Sun, Huijun; Peng, Jinyong

    2017-01-01

    The protective effects of dioscin, a natural steroidal saponin from some medicinal plants including Dioscorea nipponica Makino, against lipopolysaccharide (LPS)- induced acute liver and renal damages have been reported in our previous works. However, the actions of dioscin against LPS-induced acute lung injury (ALI) is still unknown. In the present study, we investigated the effects and mechanisms of dioscin against LPS-induced ALI in vitro and in vivo. The results showed that dioscin obviously inhibited cell proliferation and markedly decreased reactive oxidative species level in 16HBE cells treated by LPS. In addition, dioscin significantly protected LPS-induced histological changes, inhibited the infiltration of inflammatory cells, as well as decreased the levels of MDA, SOD, NO and iNOS in mice and rats (p < 0.05). Mechanistically, dioscin significantly decreased the protein levels of TLR4, MyD88, TRAF6, TKB1, TRAF3, phosphorylation levels of PI3K, Akt, IκBα, NF-κB, and the mRNA levels of IL-1β, IL-6, and TNF-α against oxidative stress and inflammation (p < 0.05). Dioscin significantly reduced the overexpression of TLR4, and obviously down-regulated the levels of MyD88, TRAF6, TKB1, TRAF3, p-PI3K, p-Akt, p-IκBα, and p-NF-κB. These findings provide new perspectives for the study of ALI. Dioscin has protective effects on LPS-induced ALI via adjusting TLR4/MyD88- mediated oxidative stress and inflammation, which should be a potent drug in the treatment of ALI. PMID:28377715

  6. Autophagy induced by AXL receptor tyrosine kinase alleviates acute liver injury via inhibition of NLRP3 inflammasome activation in mice.

    PubMed

    Han, Jihye; Bae, Joonbeom; Choi, Chang-Yong; Choi, Sang-Pil; Kang, Hyung-Sik; Jo, Eun-Kyeong; Park, Jongsun; Lee, Young Sik; Moon, Hyun-Seuk; Park, Chung-Gyu; Lee, Myung-Shik; Chun, Taehoon

    2016-12-01

    Severe hepatic inflammation is a common cause of acute or chronic liver disease. Macrophages are one of the key mediators which regulate the progress of hepatic inflammation. Increasing evidence shows that the TAM (TYRO3, AXL and MERTK) family of RTKs (receptor tyrosine kinases), which is expressed in macrophages, alleviates inflammatory responses through a negative feedback loop. However, the functional contribution of each TAM family member to the progression of hepatic inflammation remains elusive. In this study, we explore the role of individual TAM family proteins during autophagy induction and evaluate their contribution to hepatic inflammation. Among the TAM family of RTKs, AXL (AXL receptor tyrosine kinase) only induces autophagy in macrophages after interaction with its ligand, GAS6 (growth arrest specific 6). Based on our results, autophosphorylation of 2 tyrosine residues (Tyr815 and Tyr860) in the cytoplasmic domain of AXL in mice is required for autophagy induction and AXL-mediated autophagy induction is dependent on MAPK (mitogen-activated protein kinase)14 activity. Furthermore, induction of AXL-mediated autophagy prevents CASP1 (caspase 1)-dependent IL1B (interleukin 1, β) and IL18 (interleukin 18) maturation by inhibiting NLRP3 (NLR family, pyrin domain containing 3) inflammasome activation. In agreement with these observations, axl(-/-) mice show more severe symptoms than do wild-type (Axl(+/+)) mice following acute hepatic injury induced by administration of lipopolysaccharide (LPS) or carbon tetrachloride (CCl4). Hence, GAS6-AXL signaling-mediated autophagy induction in murine macrophages ameliorates hepatic inflammatory responses by inhibiting NLRP3 inflammasome activation.

  7. Pharmacologic ATM but not ATR kinase inhibition abrogates p21-dependent G1 arrest and promotes gastrointestinal syndrome after total body irradiation.

    PubMed

    Vendetti, Frank P; Leibowitz, Brian J; Barnes, Jennifer; Schamus, Sandy; Kiesel, Brian F; Abberbock, Shira; Conrads, Thomas; Clump, David Andy; Cadogan, Elaine; O'Connor, Mark J; Yu, Jian; Beumer, Jan H; Bakkenist, Christopher J

    2017-02-01

    We show that ATM kinase inhibition using AZ31 prior to 9 or 9.25 Gy total body irradiation (TBI) reduced median time to moribund in mice to 8 days. ATR kinase inhibition using AZD6738 prior to TBI did not reduce median time to moribund. The striking finding associated with ATM inhibition prior to TBI was increased crypt loss within the intestine epithelium. ATM inhibition reduced upregulation of p21, an inhibitor of cyclin-dependent kinases, and blocked G1 arrest after TBI thereby increasing the number of S phase cells in crypts in wild-type but not Cdkn1a(p21(CIP/WAF1))-/- mice. In contrast, ATR inhibition increased upregulation of p21 after TBI. Thus, ATM activity is essential for p21-dependent arrest while ATR inhibition may potentiate arrest in crypt cells after TBI. Nevertheless, ATM inhibition reduced median time to moribund in Cdkn1a(p21(CIP/WAF1))-/- mice after TBI. ATM inhibition also increased cell death in crypts at 4 h in Cdkn1a(p21(CIP/WAF1))-/-, earlier than at 24 h in wild-type mice after TBI. In contrast, ATR inhibition decreased cell death in crypts in Cdkn1a(p21(CIP/WAF1))-/- mice at 4 h after TBI. We conclude that ATM activity is essential for p21-dependent and p21-independent mechanisms that radioprotect intestinal crypts and that ATM inhibition promotes GI syndrome after TBI.

  8. Pharmacologic ATM but not ATR kinase inhibition abrogates p21-dependent G1 arrest and promotes gastrointestinal syndrome after total body irradiation

    PubMed Central

    Vendetti, Frank P.; Leibowitz, Brian J.; Barnes, Jennifer; Schamus, Sandy; Kiesel, Brian F.; Abberbock, Shira; Conrads, Thomas; Clump, David Andy; Cadogan, Elaine; O’Connor, Mark J.; Yu, Jian; Beumer, Jan H.; Bakkenist, Christopher J.

    2017-01-01

    We show that ATM kinase inhibition using AZ31 prior to 9 or 9.25 Gy total body irradiation (TBI) reduced median time to moribund in mice to 8 days. ATR kinase inhibition using AZD6738 prior to TBI did not reduce median time to moribund. The striking finding associated with ATM inhibition prior to TBI was increased crypt loss within the intestine epithelium. ATM inhibition reduced upregulation of p21, an inhibitor of cyclin-dependent kinases, and blocked G1 arrest after TBI thereby increasing the number of S phase cells in crypts in wild-type but not Cdkn1a(p21CIP/WAF1)−/− mice. In contrast, ATR inhibition increased upregulation of p21 after TBI. Thus, ATM activity is essential for p21-dependent arrest while ATR inhibition may potentiate arrest in crypt cells after TBI. Nevertheless, ATM inhibition reduced median time to moribund in Cdkn1a(p21CIP/WAF1)−/− mice after TBI. ATM inhibition also increased cell death in crypts at 4 h in Cdkn1a(p21CIP/WAF1)−/−, earlier than at 24 h in wild-type mice after TBI. In contrast, ATR inhibition decreased cell death in crypts in Cdkn1a(p21CIP/WAF1)−/− mice at 4 h after TBI. We conclude that ATM activity is essential for p21-dependent and p21-independent mechanisms that radioprotect intestinal crypts and that ATM inhibition promotes GI syndrome after TBI. PMID:28145510

  9. Impact of DPP-4 inhibition on acute and chronic endothelial function in humans with type 2 diabetes on background metformin therapy.

    PubMed

    Widlansky, Michael E; Puppala, Venkata K; Suboc, Tisha M; Malik, Mobin; Branum, Amberly; Signorelli, Kara; Wang, Jingli; Ying, Rong; Tanner, Michael J; Tyagi, Sudhi

    2017-01-01

    Cell culture and animal work indicate that dipeptidyl peptidase-4 (DPP-4) inhibition may exert cardiovascular benefits through favorable effects on the vascular endothelium. Prior human studies evaluating DPP-4 inhibition have shown conflicting results that may in part be related to heterogeneity of background anti-diabetes therapies. No study has evaluated the acute response of the vasculature to DPP-4 inhibition in humans. We recruited 38 patients with type 2 diabetes on stable background metformin therapy for a randomized, double-blind, placebo-controlled crossover trial of DPP-4 inhibition with sitagliptin (100 mg/day). Each treatment period was 8 weeks long separated by 4 weeks of washout. Endothelial function and plasma markers of endothelial activation (intercellular adhesion molecule 1 (ICAM-1) and vascular cell adhesion molecule 1 (VCAM-1)) were measured prior to and 2 hours following acute dosing of sitagliptin or placebo, as well as following 8 weeks of intervention with each pill. Thirty subjects completed the study and were included in analyses. Neither acute nor chronic sitagliptin therapy resulted in significant changes in vascular endothelial function. While post-acute sitagliptin ICAM-1 levels were lower than that post-chronic sitagliptin, the ICAM-1 concentration was not significantly different than pre-acute sitagliptin levels or levels measured in relationship to placebo. There were no significant changes in plasma VCAM-1 levels at any time point. Acute and chronic sitagliptin therapies have neutral effects on the vascular endothelium in the setting of metformin background therapy. In conclusion, our findings suggest DPP-4 inhibition has a neutral effect on cardiovascular risk in patients without a history of heart failure or renal insufficiency.

  10. Beta-adrenergic or parasympathetic inhibition, heart rate and cardiac output during normoxic and acute hypoxic exercise in humans.

    PubMed

    Hopkins, Susan R; Bogaard, Harm J; Niizeki, Kyuichi; Yamaya, Yoshiki; Ziegler, Michael G; Wagner, Peter D

    2003-07-15

    Acute hypoxia increases heart rate (HR) and cardiac output (Qt) at a given oxygen consumption (VO2) during submaximal exercise. It is widely believed that the underlying mechanism involves increased sympathetic activation and circulating catecholamines acting on cardiac beta receptors. Recent evidence indicating a continued role for parasympathetic modulation of HR during moderate exercise suggests that increased parasympathetic withdrawal plays a part in the increase in HR and Qt during hypoxic exercise. To test this, we separately blocked the beta-sympathetic and parasympathetic arms of the autonomic nervous system (ANS) in six healthy subjects (five male, one female; mean +/- S.E.M. age = 31.7+/-1.6 years, normoxic maximal VO2 (VO2,max)=3.1+/-0.3 l min(-1)) during exercise in conditions of normoxia and acute hypoxia (inspired oxygen fraction=0.125) to VO2,max. Data were collected on different days under the following conditions: (1)control, (2) after 8.0 mg propranolol i.v. and (3) after 0.8 mg glycopyrrolate i.v. Qt was measured using open-circuit acetylene uptake. Hypoxia increased venous [adrenaline] and [noradrenaline] but not [dopamine] at a given VO2 (P<0.05, P<0.01 and P=0.2, respectively). HR/VO2 and Qt/VO2 increased during hypoxia in all three conditions (P<0.05). Unexpectedly, the effects of hypoxia on HR and Qt were not significantly different from control with either beta-sympathetic or parasympathetic inhibition. These data suggest that although acute exposure to hypoxia increases circulating [catecholamines], the effects of hypoxia on HR and Qt do not necessarily require intact cardiac muscarinic and beta receptors. It may be that cardiac alpha receptors play a primary role in elevating HR and Qt during hypoxic exercise, or perhaps offer an alternative mechanism when other ANS pathways are blocked.

  11. Effects of acute aerobic exercise on neural correlates of attention and inhibition in adolescents with bipolar disorder

    PubMed Central

    Metcalfe, A W S; MacIntosh, B J; Scavone, A; Ou, X; Korczak, D; Goldstein, B I

    2016-01-01

    Executive dysfunction is common during and between mood episodes in bipolar disorder (BD), causing social and functional impairment. This study investigated the effect of acute exercise on adolescents with BD and healthy control subjects (HC) to test for positive or negative consequences on neural response during an executive task. Fifty adolescents (mean age 16.54±1.47 years, 56% female, 30 with BD) completed an attention and response inhibition task before and after 20 min of recumbent cycling at ~70% of age-predicted maximum heart rate. 3 T functional magnetic resonance imaging data were analyzed in a whole brain voxel-wise analysis and as regions of interest (ROI), examining Go and NoGo response events. In the whole brain analysis of Go trials, exercise had larger effect in BD vs HC throughout ventral prefrontal cortex, amygdala and hippocampus; the profile of these effects was of greater disengagement after exercise. Pre-exercise ROI analysis confirmed this 'deficit in deactivation' for BDs in rostral ACC and found an activation deficit on NoGo errors in accumbens. Pre-exercise accumbens NoGo error activity correlated with depression symptoms and Go activity with mania symptoms; no correlations were present after exercise. Performance was matched to controls and results survived a series of covariate analyses. This study provides evidence that acute aerobic exercise transiently changes neural response during an executive task among adolescents with BD, and that pre-exercise relationships between symptoms and neural response are absent after exercise. Acute aerobic exercise constitutes a biological probe that may provide insights regarding pathophysiology and treatment of BD. PMID:27187236

  12. GSPE Inhibits HMGB1 Release, Attenuating Renal IR-Induced Acute Renal Injury and Chronic Renal Fibrosis

    PubMed Central

    Zhan, Juan; Wang, Kun; Zhang, Conghui; Zhang, Chunxiu; Li, Yueqiang; Zhang, Ying; Chang, Xiaoyan; Zhou, Qiaodan; Yao, Ying; Liu, Yanyan; Xu, Gang

    2016-01-01

    Grape seed proanthocyanindin extract (GSPE) is a polyphenolic bioflavonoid derived from grape seeds and has been widely studied for its potent antioxidant, anti-inflammatory and antitumor activities. HMGB1 is a newly discovered danger-associated molecular pattern (DAMP) that has potent proinflammatory effects once released by necrotic cells. However, the effect of GSPE on the HMGB1, and the relationship of those two with acute kidney injury and chronic kidney fibrosis are unknown. This study aimed to investigate the impact of GSPE on acute kidney injury and chronic fibrosis. C57bl/6 mice were subjected to bilateral ischemia/reperfusion (I/R) and unilateral I/R with or without GSPE administration. After bilateral I/R, mice administered GSPE had a marked improvement in renal function (BUN and Cr), decreased pathological damage and reduced inflammation. In unilateral I/R, mice subjected GSPE showed reduced tubulointerstitial fibrosis and decreased inflammatory reaction. The renoprotection of GSPE on both models was associated with the inhibition of HMGB1 nucleocytoplasmic shuttling and release, which can amplify the inflammation through binding to its downstream receptor TLR4 and facilitated P65 transcription. Thus, we have reason to believe that GSPE could be a good alternative therapy for the prevention and treatment of IR-induced renal injury and fibrosis in clinical practice. PMID:27690015

  13. FAAH inhibition produces antidepressant-like efforts of mice to acute stress via synaptic long-term depression.

    PubMed

    Wang, Ying; Zhang, Xia

    2017-05-01

    Recent studies have shown that inhibition of fatty acid amide hydrolase (FAAH), the major degradative enzyme of the endocannabinoid N-arachidonoylethanolamine (AEA), produced antidepressant behavioral responses, but its underlying mechanism is not clear. Here we find that a systemic administration of the FAAH inhibitor PF3845 or an intra-CA1 application of AEA elicits an in vivo long-term depression (LTD) at excitatory glutamatergic CA3-CA1 synapses of the hippocampus. The PF3845- and/or AEA-elicited LTD are abolished by the LTD-blocking peptide Tat-GluR2. PF3845 significantly decreases passive behavioral coping of naïve mice to acute inescapable stress, which is also abolished by Tat-GluR2 peptide. However, PF3845 does not significantly affect sucrose assumption ratio of mice receiving chronic administration of corticosterone. These results suggest that FAAH inhibitors are able to produce antidepressant effects in naïve animals in response to acute stress through LTD at hippocampal glutamatergic CA3-CA1 synapses.

  14. NDRG1/2 expression is inhibited in primary acute myeloid leukemia.

    PubMed

    Tschan, Mario P; Shan, Deborah; Laedrach, Judith; Eyholzer, Marianne; Leibundgut, Elisabeth Oppliger; Baerlocher, Gabriela M; Tobler, Andreas; Stroka, Deborah; Fey, Martin F

    2010-03-01

    Expression of N-myc downregulated gene 1 (NDRG1) is associated with growth arrest and differentiation of tumor cells. In hematopoietic cells, NDRG1 was identified in a screen for differentiation-related genes in human myelomonocytic leukemic U937 cells. In the present study, we found significantly higher NDRG1 mRNA levels in granulocytes of healthy donors than in primary acute myeloid leukemia (AML) cells. Another NDRG family member, NDRG2, was significantly higher expressed in normal macrophages compared to primary AML cells. Moreover, NDRG1 mRNA levels increased in two acute promyelocytic leukemia (APL) patients as well as in NB4 and HT93 APL cells upon all-trans retinoic acid (ATRA) therapy. In line with these observations, silencing of NDRG1 diminished neutrophil differentiation of leukemic cell lines. In conclusion, we found an association of low NDRG1 levels with an immature cell phenotype and provide evidence that NDRG1 is functionally involved in neutrophil maturation.

  15. Acute Ethanol Inhibition of γ Oscillations Is Mediated by Akt and GSK3β

    PubMed Central

    Wang, JianGang; Zhao, JingXi; Liu, ZhiHua; Guo, FangLi; Wang, Yali; Wang, Xiaofang; Zhang, RuiLing; Vreugdenhil, Martin; Lu, Chengbiao

    2016-01-01

    Hippocampal network oscillations at gamma band frequency (γ, 30–80 Hz) are closely associated with higher brain functions such as learning and memory. Acute ethanol exposure at intoxicating concentrations (≥50 mM) impairs cognitive function. This study aimed to determine the effects and the mechanisms of acute ethanol exposure on γ oscillations in an in vitro model. Ethanol (25–100 mM) suppressed kainate-induced γ oscillations in CA3 area of the rat hippocampal slices, in a concentration-dependent, reversible manner. The ethanol-induced suppression was reduced by the D1R antagonist SCH23390 or the PKA inhibitor H89, was prevented by the Akt inhibitor triciribine or the GSk3β inhibitor SB415286, was enhanced by the NMDA receptor antagonist D-AP5, but was not affected by the MAPK inhibitor U0126 or PI3K inhibitor wortmanin. Our results indicate that the intracellular kinases Akt and GSk3β play a critical role in the ethanol-induced suppression of γ oscillations and reveal new cellular pathways involved in the ethanol-induced cognitive impairment. PMID:27582689

  16. Jumihaidokuto effectively inhibits colon inflammation and apoptosis in mice with acute colitis.

    PubMed

    Sreedhar, Remya; Arumugam, Somasundaram; Karuppagounder, Vengadeshprabhu; Thandavarayan, Rajarajan A; Giridharan, Vijayasree V; Pitchaimani, Vigneshwaran; Afrin, Mst Rejina; Harima, Meilei; Nakamura, Takashi; Nakamura, Masahiko; Suzuki, Kenji; Watanabe, Kenichi

    2015-12-01

    Jumihaidokuto, a Japanese kampo medicine, is prescribed in Japan for its anti-inflammatory activity. Here we have examined its beneficial effects against acute colitis induced by dextran sulfate sodium (DSS) in mice. We have used C57BL/6 female mice, divided into two groups and received 3% DSS in drinking water during the experimental period (8days). Treatment group mice received 1g/kg/day dose of Jumihaidokuto orally whereas DSS control group received equal volume of distilled water. Normal control group mice received plain drinking water. Jumihaidokuto treatment attenuated the colitis symptoms along with suppression of various inflammatory marker proteins such as IL-1β, IL-2Rα, IL-4, CTGF and RAGE. It has also down-regulated the oxidative stress and apoptotic signaling in the colons of mice with colitis. The present study has confirmed the beneficial effects of Jumihaidokuto on DSS induced acute colitis in mice and suggests that it can be a potential agent for the treatment of colitis.

  17. Neuroprotective effect of acute melatonin treatment on hippocampal neurons against irradiation by inhibition of caspase-3

    PubMed Central

    LI, JIANGUO; ZHANG, GUOWEI; MENG, ZHUANGZHI; WANG, LINGZHAN; LIU, HAIYING; LIU, QIANG; BUREN, BATU

    2016-01-01

    Neuronal cell apoptosis is associated with various factors that induce neurological damage, including radiation exposure. When administered prior to exposure to radiation, a protective agent may prevent cellular and molecular injury. The present study aimed to investigate whether melatonin exerts a neuroprotective effect by inhibiting the caspase cell death pathway. Male Sprague-Dawley rats were administered melatonin (100 mg/kg body weight) 30 min prior to radiation exposure in red light during the evening. In order to elucidate whether melatonin has a neuroprotective role, immunohistochemistry, terminal deoxynucleotidyl transferase dUTP nick-end labeling, Nissl staining, reverse transcription-quantitative polymerase chain reaction, reactive oxygen species analysis and western blotting were performed. At 24 h post-melatonin treatment, caspase-3 mRNA and protein expression levels were significantly decreased. These results demonstrated that melatonin may protect hippocampal neurons via the inhibition of caspase-3 when exposed to irradiation. Therefore, caspase-3 inhibition serves a neuroprotective and antioxidant role in the interventional treatment of melatonin. The results of the present study suggested that melatonin may have a potential therapeutic effect against irradiation; however, further studies are required in order to elucidate the underlying antioxidant mechanisms. PMID:27313671

  18. Effects of Acute Nitric Oxide Synthase Inhibition on Lower Leg Vascular Function in Chronic Tetraplegia

    PubMed Central

    La Fountaine, Michael F; Radulovic, Miroslav; Cardozo, Christopher P; Spungen, Ann M; DeMeersman, Ronald E; Bauman, William A

    2009-01-01

    Background/Objective: To improve our understanding of the lower-leg vascular responses of nitric oxide synthase inhibition in persons with tetraplegia. Participants: Six people with chronic tetraplegia and 6 age-matched controls. Methods: Lower-leg relative vascular resistance and venous volume variation were obtained by venous occlusion plethysmography and blood pressure by auscultation at baseline. Postintravenous infusion of the nitric oxide synthase inhibitor NG-nitro-l-arginine-methyl-ester (1 mg·kg−1) or placebo on separate days. Results: At baseline in the group with tetraplegia compared with controls, mean arterial pressure and relative vascular resistance of the leg were significantly lower. After nitric oxide synthase inhibition, mean arterial pressure and lower leg vascular resistance were significantly elevated in both groups. There were no group or intervention differences in venous volume variation. Conclusion: These preliminary results suggest that nitric oxide synthase inhibition with 1 mg·kg−1 NG-nitro-l-arginine-methyl-ester normalizes seated blood pressure and lower leg vascular resistance to control group baseline levels. PMID:20025149

  19. Fucoidan inhibits LPS-induced inflammation in vitro and during the acute response in vivo.

    PubMed

    Park, Jisang; Cha, Jeong-Dan; Choi, Kyung-Min; Lee, Kyung-Yeol; Han, Kang Min; Jang, Yong-Suk

    2017-02-01

    Studies have been focused on natural products with antibacterial and anti-inflammatory activities, such as fucoidan. Many in vivo studies have evaluated the effect of fucoidan on tumor growth, diabetes, obesity, ischemia reperfusion, and oxidative stress. However, the effects of fucoidan on bacteria-induced gingival inflammation and periodontitis have not been reported. We previously characterized the anti-inflammatory effect of fucoidan in vitro. Here, we confirmed the anti-inflammatory activity of fucoidan in a macrophage cell line in terms of its inhibition of the expression of inflammatory mediators and pro-inflammatory cytokines. Additionally, we confirmed the ability of fucoidan to inhibit gingival inflammation, expression of pro-inflammatory cytokines, and neutrophil recruitment in the gingival tissue of mice injected with LPS prepared from P. gingivalis. Interestingly, however, fucoidan did not inhibit the expression of pro-inflammatory cytokines in a P. gingivalis-infected mouse model of periodontitis. Additionally, fucoidan treatment did not lead to clearance of P. gingivalis or improvement of P. gingivalis infection-mediated bone loss in the periodontitis model. We conclude that fucoidan exerts anti-inflammatory effects in vitro and in vivo, together with a limited antibacterial effect in vivo.

  20. High glucose-induced mitochondrial respiration and reactive oxygen species in mouse cerebral pericytes is reversed by pharmacological inhibition of mitochondrial carbonic anhydrases: Implications for cerebral microvascular disease in diabetes.

    PubMed

    Shah, Gul N; Morofuji, Yoichi; Banks, William A; Price, Tulin O

    2013-10-18

    Hyperglycemia-induced oxidative stress leads to diabetes-associated damage to the microvasculature of the brain. Pericytes in close proximity to endothelial cells in the brain microvessels are vital to the integrity of the blood-brain barrier and are especially susceptible to oxidative stress. According to our recently published results, streptozotocin-diabetic mouse brain exhibits oxidative stress and loose pericytes by twelve weeks of diabetes, and cerebral pericytes cultured in high glucose media suffer intracellular oxidative stress and apoptosis. Oxidative stress in diabetes is hypothesized to be caused by reactive oxygen species (ROS) produced during hyperglycemia-induced enhanced oxidative metabolism of glucose (respiration). To test this hypothesis, we investigated the effect of high glucose on respiration rate and ROS production in mouse cerebral pericytes. Previously, we showed that pharmacological inhibition of mitochondrial carbonic anhydrases protects the brain from oxidative stress and pericyte loss. The high glucose-induced intracellular oxidative stress and apoptosis of pericytes in culture were also reversed by inhibition of mitochondrial carbonic anhydrases. Therefore, we extended our current study to determine the effect of these inhibitors on high glucose-induced increases in pericyte respiration and ROS. We now report that both the respiration and ROS are significantly increased in pericytes challenged with high glucose. Furthermore, inhibition of mitochondrial carbonic anhydrases significantly slowed down both the rate of respiration and ROS production. These data provide new evidence that pharmacological inhibitors of mitochondrial carbonic anhydrases, already in clinical use, may prove beneficial in protecting the brain from oxidative stress caused by ROS produced as a consequence of hyperglycemia-induced enhanced respiration.

  1. Dexmedetomidine attenuates lipopolysaccharide-induced acute lung injury by inhibiting oxidative stress, mitochondrial dysfunction and apoptosis in rats

    PubMed Central

    Fu, Chunlai; Dai, Xingui; Yang, You; Lin, Mengxiang; Cai, Yeping; Cai, Shaoxi

    2016-01-01

    Previous studies have identified that dexmedetomidine (DEX) treatment can ameliorate the acute lung injury (ALI) induced by lipopolysaccharide and ischemia-reperfusion. However, the molecular mechanisms by which DEX ameliorates lung injury remain unclear. The present study investigated whether DEX, which has been reported to exert effects on oxidative stress, mitochondrial permeability transition pores and apoptosis in other disease types, can exert protective effects in lipopolysaccharide (LPS)-induced ALI by inhibiting oxidative stress, mitochondrial dysfunction and mitochondrial-dependent apoptosis. It was revealed that LPS-challenged rats exhibited significant lung injury, characterized by the deterioration of histopathology, vascular hyperpermeability, wet-to-dry weight ratio and oxygenation index (PaO2/FIO2), which was attenuated by DEX treatment. DEX treatment inhibited LPS-induced mitochondrial dysfunction, as evidenced by alleviating the cellular ATP and mitochondrial membrane potential in vitro. In addition, DEX treatment markedly prevented the LPS-induced mitochondrial-dependent apoptotic pathway in vitro (increases of cell apoptotic rate, cytosolic cytochrome c, and caspase 3 activity) and in vivo (increases of |terminal deoxynucleotidyl transferase dUTP nick-end labeling positive cells, cleaved caspase 3, Bax upregulation and Bcl-2 downregulation). Furthermore, DEX treatment markedly attenuated LPS-induced oxidative stress, as evidenced by downregulation of cellular reactive oxygen species in vitro and lipid peroxides in serum. Collectively, the present results demonstrated that DEX ameliorates LPS-induced ALI by reducing oxidative stress, mitochondrial dysfunction and mitochondrial-dependent apoptosis. PMID:27959438

  2. Interferon-alpha production by swine dendritic cells is inhibited during acute infection with foot-and-mouth disease virus.

    PubMed

    Nfon, Charles K; Ferman, Geoffrey S; Toka, Felix N; Gregg, Douglas A; Golde, William T

    2008-03-01

    Viruses have evolved multiple mechanisms to evade the innate immune response, particularly the actions of interferons (IFNs). We have previously reported that exposure of dendritic cells (DCs) to foot-and-mouth disease virus (FMDV) in vitro yields no infection and induces a strong type I IFN (IFN-alpha and IFN-beta) response, indicating that DCs may play a critical role in the innate response to the virus. In vivo, FMDV induces lymphopenia and reduced T-cell proliferative responses to mitogen, viral effects that may contribute to evasion of early immune responses. In this study we analyzed the in vivo effects of FMDV infection on the IFN-alpha response of two populations of dendritic cells. During the acute phase of infection of swine, production of IFN-alpha from monocyte-derived DCs (MoDCs) and skin-derived DCs (skin DCs) is inhibited. This effect occurs concurrently with rising viral titers in the blood; however, these cells are not productively infected. Interestingly, there are no changes in the capability of these DCs to take up particles and process antigens, indicating that antigen-presenting cell function is normal. These data indicate that inhibition of the IFN-alpha response of dendritic cell populations from blood and skin by FMDV enhances viral pathogenesis in infected animals.

  3. Dexmedetomidine attenuates lipopolysaccharide-induced acute lung injury by inhibiting oxidative stress, mitochondrial dysfunction and apoptosis in rats.

    PubMed

    Fu, Chunlai; Dai, Xingui; Yang, You; Lin, Mengxiang; Cai, Yeping; Cai, Shaoxi

    2017-01-01

    Previous studies have identified that dexmedetomidine (DEX) treatment can ameliorate the acute lung injury (ALI) induced by lipopolysaccharide and ischemia-reperfusion. However, the molecular mechanisms by which DEX ameliorates lung injury remain unclear. The present study investigated whether DEX, which has been reported to exert effects on oxidative stress, mitochondrial permeability transition pores and apoptosis in other disease types, can exert protective effects in lipopolysaccharide (LPS)‑induced ALI by inhibiting oxidative stress, mitochondrial dysfunction and mitochondrial‑dependent apoptosis. It was revealed that LPS‑challenged rats exhibited significant lung injury, characterized by the deterioration of histopathology, vascular hyperpermeability, wet‑to‑dry weight ratio and oxygenation index (PaO2/FIO2), which was attenuated by DEX treatment. DEX treatment inhibited LPS‑induced mitochondrial dysfunction, as evidenced by alleviating the cellular ATP and mitochondrial membrane potential in vitro. In addition, DEX treatment markedly prevented the LPS‑induced mitochondrial‑dependent apoptotic pathway in vitro (increases of cell apoptotic rate, cytosolic cytochrome c, and caspase 3 activity) and in vivo (increases of |terminal deoxynucleotidyl transferase dUTP nick‑end labeling positive cells, cleaved caspase 3, Bax upregulation and Bcl‑2 downregulation). Furthermore, DEX treatment markedly attenuated LPS‑induced oxidative stress, as evidenced by downregulation of cellular reactive oxygen species in vitro and lipid peroxides in serum. Collectively, the present results demonstrated that DEX ameliorates LPS‑induced ALI by reducing oxidative stress, mitochondrial dysfunction and mitochondrial-dependent apoptosis.

  4. PEDF improves cardiac function in rats with acute myocardial infarction via inhibiting vascular permeability and cardiomyocyte apoptosis.

    PubMed

    Zhang, Hao; Wang, Zheng; Feng, Shou-Jie; Xu, Lei; Shi, He-Xian; Chen, Li-Li; Yuan, Guang-Da; Yan, Wei; Zhuang, Wei; Zhang, Yi-Qian; Zhang, Zhong-Ming; Dong, Hong-Yan

    2015-03-11

    Pigment epithelium-derived factor (PEDF) is a pleiotropic gene with anti-inflammatory, antioxidant and anti-angiogenic properties. However, recent reports about the effects of PEDF on cardiomyocytes are controversial, and it is not known whether and how PEDF acts to inhibit hypoxic or ischemic endothelial injury in the heart. In the present study, adult Sprague-Dawley rat models of acute myocardial infarction (AMI) were surgically established. PEDF-small interfering RNA (siRNA)-lentivirus (PEDF-RNAi-LV) or PEDF-LV was delivered into the myocardium along the infarct border to knockdown or overexpress PEDF, respectively. Vascular permeability, cardiomyocyte apoptosis, myocardial infarct size and animal cardiac function were analyzed. We also evaluated PEDF's effect on the suppression of the endothelial permeability and cardiomyocyte apoptosis under hypoxia in vitro. The results indicated that PEDF significantly suppressed the vascular permeability and inhibited hypoxia-induced endothelial permeability through PPARγ-dependent tight junction (TJ) production. PEDF protected cardiomyocytes against ischemia or hypoxia-induced cell apoptosis both in vivo and in vitro via preventing the activation of caspase-3. We also found that PEDF significantly reduced myocardial infarct size and enhanced cardiac function in rats with AMI. These data suggest that PEDF could protect cardiac function from ischemic injury, at least by means of reducing vascular permeability, cardiomyocyte apoptosis and myocardial infarct size.

  5. Small Molecule Inhibition of cAMP Response Element Binding Protein in Human Acute Myeloid Leukemia Cells

    PubMed Central

    Mitton, Bryan; Chae, Hee-Don; Hsu, Katie; Dutta, Ritika; Aldana-Masangkay, Grace; Ferrari, Roberto; Davis, Kara; Tiu, Bruce C.; Kaul, Arya; Lacayo, Norman; Dahl, Gary; Xie, Fuchun; Li, Bingbing X.; Breese, Marcus R.; Landaw, Elliot M.; Nolan, Garry; Pellegrini, Matteo; Romanov, Sergei; Xiao, Xiangshu; Sakamoto, Kathleen M.

    2016-01-01

    The transcription factor CREB (cAMP Response Element Binding Protein) is overexpressed in the majority of acute myeloid leukemia (AML) patients, and this is associated with a worse prognosis. Previous work revealed that CREB overexpression augmented AML cell growth, while CREB knockdown disrupted key AML cell functions in vitro. In contrast, CREB knockdown had no effect on long-term hematopoietic stem cell activity in mouse transduction/transplantation assays. Together, these studies position CREB as a promising drug target for AML. To test this concept, a small molecule inhibitor of CREB, XX-650-23, was developed. This molecule blocks a critical interaction between CREB and its required co-activator CBP (CREB Binding Protein), leading to disruption of CREB-driven gene expression. Inhibition of CBP-CREB interaction induced apoptosis and cell cycle arrest in AML cells, and prolonged survival in vivo in mice injected with human AML cells. XX-650-23 had little toxicity on normal human hematopoietic cells and tissues in mice. To understand the mechanism of XX-650-23, we performed RNA-seq, ChIP-seq and Cytometry Time of Flight with human AML cells. Our results demonstrate that small molecule inhibition of CBP-CREB interaction mostly affects apoptotic, cell cycle, and survival pathways, which may represent a novel approach for AML therapy. PMID:27211267

  6. Zingerone ameliorates lipopolysaccharide-induced acute kidney injury by inhibiting Toll-like receptor 4 signaling pathway.

    PubMed

    Song, Jie; Fan, Hao-jun; Li, Hui; Ding, Hui; Lv, Qi; Hou, Shi-ke

    2016-02-05

    Acute kidney injury (AKI) is a serious complication of sepsis. Zingerone, a phenolic alkanone isolated from ginger, has been reported to have anti-inflammatory effect. The aim of this study was to investigate the therapeutic effects of zingerone on lipopolysaccharide (LPS)-induced AKI in mice. Zingerone was administrated 1h after LPS challenge. The production of blood urea nitrogen (BUN) and creatinine were measured in this study. The expressions of inflammatory cytokines in serum and kidney tissues were detected by ELISA. The expressions of Toll-like receptor 4 (TLR4), MyD88, TRIF, Nuclear factor Kappa B (NF-κB) and IκB were measured by Western blotting. The results showed that zingerone suppressed LPS-induced BUN, creatinine, and inflammatory cytokines TNF-α, IL-6 and IL-1β levels in a dose-dependent manner. Zingerone also attenuated LPS-induced kidney histopathologic changes. Furthermore, zingerone was found to inhibit LPS-induced TLR4, MyD88, TRIF expression and NF-κB activation. In conclusion, the current study demonstrated that zingerone inhibited LPS-induced AKI by suppressing TLR4/NF-κB signaling pathway.

  7. Protective effect of Trillium tschonoskii saponin on CCl4-induced acute liver injury of rats through apoptosis inhibition.

    PubMed

    Wu, Hao; Qiu, Yong; Shu, Ziyang; Zhang, Xu; Li, Renpeng; Liu, Su; Chen, Longquan; Liu, Hong; Chen, Ning

    2016-12-01

    To explore hepatoprotective role and underlying mechanisms of Trillium tschonoskii Maxim (TTM), 36 rats were randomly divided into control, CCl4-induced liver injury model, and biphenyl dimethyl dicarboxylate (DDB) and low-, moderate-, and high-dose TTM treatment groups. After CCl4-induced model establishment, the rats from DDB and TTM groups were administrated with DDB at 0.2 g/kg per day and TTM at 0.1, 0.5, and 1.0 g/kg per day, while the rats from control and model groups were administrated with saline. After 5 days of treatments, all rats were sacrificed for determining serum ALT and AST levels and liver index, examining histopathological changes in liver through HE and TUNEL staining, and evaluating TNF-α and IL-6 mRNA expression by real-time PCR, and caspase-3, Bcl-2, and Bax expression by Western blot. Results indicated that CCl4 could induce acute liver injury and abnormal liver function in rats with obvious hepatomegaly, increased liver index, high ALT and AST levels, up-regulated TNF-α and IL-6, and overexpressed Bax and caspase-3. However, DDB and TTM could execute protective role in CCl4-induced liver injury in rats through reducing ALT and AST levels, rescuing hepatomegaly, down-regulating inflammatory factors and inhibiting hepatocyte apoptosis in a dose-dependent manner. Therefore, TTM has obvious protective role in CCl4-induced liver injury of rats through inhibiting hepatocyte apoptosis.

  8. Integrated in vivo genetic and pharmacologic screening identifies co-inhibition of EGRF and ROCK as a potential treatment regimen for triple-negative breast cancer

    PubMed Central

    Iskit, Sedef; Lieftink, Cor; Halonen, Pasi; Shahrabi, Aida; Possik, Patricia A.; Beijersbergen, Roderick L.; Peeper, Daniel S.

    2016-01-01

    Breast cancer is the second most common cause of cancer-related deaths worldwide among women. Despite several therapeutic options, 15% of breast cancer patients succumb to the disease owing to tumor relapse and acquired therapy resistance. Particularly in triple-negative breast cancer (TNBC), developing effective treatments remains challenging owing to the lack of a common vulnerability that can be exploited by targeted approaches. We have previously shown that tumor cells have different requirements for growth in vivo than in vitro. Therefore, to discover novel drug targets for TNBC, we performed parallel in vivo and in vitro genetic shRNA dropout screens. We identified several potential drug targets that were required for tumor growth in vivo to a greater extent than in vitro. By combining pharmacologic inhibitors acting on a subset of these candidates, we identified a synergistic interaction between EGFR and ROCK inhibitors. This combination effectively reduced TNBC cell growth by inducing cell cycle arrest. These results illustrate the power of in vivo genetic screens and warrant further validation of EGFR and ROCK as combined pharmacologic targets for breast cancer. PMID:27374095

  9. Integrated in vivo genetic and pharmacologic screening identifies co-inhibition of EGRF and ROCK as a potential treatment regimen for triple-negative breast cancer.

    PubMed

    Iskit, Sedef; Lieftink, Cor; Halonen, Pasi; Shahrabi, Aida; Possik, Patricia A; Beijersbergen, Roderick L; Peeper, Daniel S

    2016-07-12

    Breast cancer is the second most common cause of cancer-related deaths worldwide among women. Despite several therapeutic options, 15% of breast cancer patients succumb to the disease owing to tumor relapse and acquired therapy resistance. Particularly in triple-negative breast cancer (TNBC), developing effective treatments remains challenging owing to the lack of a common vulnerability that can be exploited by targeted approaches. We have previously shown that tumor cells have different requirements for growth in vivo than in vitro. Therefore, to discover novel drug targets for TNBC, we performed parallel in vivo and in vitro genetic shRNA dropout screens. We identified several potential drug targets that were required for tumor growth in vivo to a greater extent than in vitro. By combining pharmacologic inhibitors acting on a subset of these candidates, we identified a synergistic interaction between EGFR and ROCK inhibitors. This combination effectively reduced TNBC cell growth by inducing cell cycle arrest. These results illustrate the power of in vivo genetic screens and warrant further validation of EGFR and ROCK as combined pharmacologic targets for breast cancer.

  10. Inhibition of glutaminase selectively suppresses the growth of primary acute myeloid leukemia cells with IDH mutations.

    PubMed

    Emadi, Ashkan; Jun, Sung Ah; Tsukamoto, Takashi; Fathi, Amir T; Minden, Mark D; Dang, Chi V

    2014-04-01

    The incidence of mutations in isocitrate dehydrogenase 1 and 2 (IDH1/2) in de novo acute myeloid leukemia (AML) is approximately 20%. These mutations result in distinct metabolic characteristics including dependency of cancer cells on glutamine as the main source for α-ketoglutarate, which is consumed by leukemia cells to produce a cancer-derived metabolite, 2-hydroxyglutarate. We sought to exploit this glutamine addiction therapeutically in mutant IDH primary AML cells from patients by measuring cell growth after exposure to a small molecule glutaminase inhibitor, BPTES. We found that BPTES only suppressed the growth of AML cells expressing mutant IDH compared with those expressing wild type IDH. This study lays the groundwork for strategies to target a specific subtype of AML metabolically with IDH mutations with a unique reprogramming of intermediary metabolism that culminates in glutamine dependency of cancer cells for survival.

  11. Inhibition of MDMA-induced increase in cortisol does not prevent acute impairment of verbal memory

    PubMed Central

    Kuypers, KPC; Torre, R; Farre, M; Pujadas, M; Ramaekers, JG

    2013-01-01

    Background Ecstasy use is commonly linked with memory deficits in abstinent ecstasy users. Similar impairments are being found during ecstasy intoxication after single doses of ± 3,4 metylenedioxymethamphetamine (MDMA). The concordance of memory impairments during intoxication and abstinence suggests a similar neuropharmacological mechanism underlying acute and chronic memory impairments. The mechanism underlying this impairment is to date not known. We hypothesized that cortisol might play an important role in this mechanism as cortisol, implicated in the regulation of memory performance, can be brought out of balance by stressors like MDMA. Methods In the present study, we aimed to block the MDMA-induced acute memory defect by giving participants a cortisol synthesis inhibitor (metyrapone) together with a single dose of MDMA. Seventeen polydrug MDMA users entered this placebo-controlled within subject study with four treatment conditions. The treatments consisted of MDMA (75 mg) and metyrapone (750 mg), alone and in combination, and double placebo. Pre-treatment with metyrapone or Placebo occurred 1 h prior to MDMA or Placebo administration. Memory performance was tested at peak drug concentrations by means of several memory tests. Cortisol levels were determined in blood and oral fluid; this served as a control measure to see whether manipulations were effective. Results Main findings indicated that whereas treatment with metyrapone blocked the expected MDMA-induced increase in cortisol levels in blood, it did not prevent the MDMA-induced memory deficit from happening. Conclusion We therefore conclude that MDMA-induced increments in cortisol concentrations are not related to MDMA-induced memory impairments. PMID:22946487

  12. Acute injection of ASP in the third ventricle inhibits food intake and locomotor activity in rats.

    PubMed

    Roy, Christian; Roy, Marie-Claude; Gauvreau, Danny; Poulin, Anne-Marie; Tom, Fun-Qun; Timofeeva, Elena; Richard, Denis; Cianflone, Katherine

    2011-07-01

    Acylation-stimulating protein (ASP; also known as C3adesArg) stimulates triglyceride synthesis and glucose transport via interaction with its receptor C5L2, which is expressed peripherally (adipose tissue, muscle) and centrally. Previous studies have shown that ASP-deficient mice (C3KO) and C5L2-deficient mice (C5L2KO) are hyperphagic (59 to 229% increase, P < 0.0001), which is counterbalanced by increased energy expenditure measured as oxygen consumption (Vo(2)) and a lower RQ. The aim of the present study was to evaluate ASP's effect on food intake, energy expenditure, and neuropeptide expression. Male rats were surgically implanted with intracerebroventricular (icv) cannulas directed toward the third ventricle. After a 5-h fast, rats were injected, and food intake was assessed at 0.5, 1, 2, 4, 16, 24, and 48 h, with a 5- to 7-day washout period between each injection. Acute icv injections of ASP (0.3-1,065 pmol) had a time-dependent effect on decreasing food intake by 20 to 57% (P < 0.05). Decreases were detected by 30 min (maximum 57%, P < 0.01) and at the highest dose effects extended to 48 h (19%, P < 0.05, 24- to 48-h period). Daily body weight gain was decreased by 131% over the first 24 h and 29% over the second 24 h (P < 0.05). A conditioned taste aversion test indicated that there was no malaise. Furthermore, acute ASP injection affected energy substrate usage, demonstrated by decreased Vo(2) and RQ (P < 0.05; implicating greater fatty acid usage), with a 49% decrease in total activity over 24 h (P < 0.05). ASP administration also increased anorexic neuropeptide POMC expression (44%) in the arcuate nucleus, with no change in NPY. Altogether ASP may have central in addition to peripheral effects.

  13. Cholinesterase Inhibition and Depression of the Photic After Discharge of Flash Evoked Potentials Following Acute or Repeated Exposures to a Mixture of Carbaryl and Propoxur

    EPA Science Inventory

    While information exists regarding inhibition of cholinesterase (ChE) activity, little is known about neurophysiological changes produced by a mixture of N-methyl carbamate pesticides. Previously, we reported that acute treatment with propoxur or carbaryl decreased the duration o...

  14. Inflammation and exercise: Inhibition of monocytic intracellular TNF production by acute exercise via β2-adrenergic activation.

    PubMed

    Dimitrov, Stoyan; Hulteng, Elaine; Hong, Suzi

    2017-03-01

    Regular exercise is shown to exert anti-inflammatory effects, yet the effects of acute exercise on cellular inflammatory responses and its mechanisms remain unclear. We tested the hypothesis that sympathoadrenergic activation during a single bout of exercise has a suppressive effect on monocytic cytokine production mediated by β2 adrenergic receptors (AR). We investigated the effects of 20-min moderate (65-70% VO2 peak) exercise-induced catecholamine production on LPS-stimulated TNF production by monocytes in 47 healthy volunteers and determined AR subtypes involved. We also examined the effects of β-agonist isoproterenol and endogenous β- and α-agonists epinephrine and norepinephrine, and receptor-subtype-specific β- and α-antagonists on TNF production in a series of in vitro investigations. LPS-stimulated TNF production by peripheral blood monocytes was determined intracellularly by flow cytometry, using an intracellular protein transport inhibitor. Percent TNF-producing monocytes and per-cell TNF production with and without LPS was suppressed by exercise with moderate to large effects, which was reversed by a β2-AR antagonist in spite that plasma TNF levels did not change. This inhibitory response in TNF production by exercise was mirrored by β-AR agonists in an agonist-specific and dose-dependent manner in vitro: similar isoproterenol (EC50=2.1-4.7×10(-10)M) and epinephrine (EC50=4.4-10×10(-10)M) potency and higher norepinephrine concentrations (EC50=2.6-4.3×10(-8)M) needed for the effects. Importantly, epinephrine levels observed during acute exercise in vivo significantly inhibited TNF production in vitro. The inhibitory effect of the AR agonists was abolished by β2-, but not by β1- or α-AR blockers. We conclude that the downregulation of monocytic TNF production during acute exercise is mediated by elevated epinephrine levels through β2-ARs. Decreased inflammatory responses during acute exercise may protect against chronic conditions with low

  15. Prostaglandin E(2) inhibits calcium current in two sub-populations of acutely isolated mouse trigeminal sensory neurons.

    PubMed

    Borgland, Stephanie L; Connor, Mark; Ryan, Renae M; Ball, Helen J; Christie, MacDonald J

    2002-03-01

    Prostaglandins are important mediators of pain and inflammation. We have examined the effects of prostanoids on voltage-activated calcium currents (I(Ca)) in acutely isolated mouse trigeminal sensory neurons, using standard whole cell voltage clamp techniques. Trigeminal neurons were divided into two populations based on the presence (Type 2) or absence (Type 1) of low voltage-activated T-type I(Ca). The absence of T-type I(Ca) is highly correlated with sensitivity to mu-opioid agonists and the VR1 agonist capsaicin. In both populations of cells, high voltage-activated I(Ca) was inhibited by PGE(2) with an EC(50) of about 35 nM, to a maximum of 30 %. T-type I(Ca) was not inhibited by PGE(2). Pertussis toxin pre-treatment abolished the effects of PGE(2) in Type 2 cells, but not in Type 1 cells, whereas treatment with cholera toxin prevented the effects of PGE(2) in Type 1 cells, but not in Type 2 cells. Inhibition of I(Ca) by PGE(2) was associated with slowing of current activation and could be relieved with a large positive pre-pulse, consistent with inhibition of I(Ca) by G protein betagamma subunits. Reverse transcription-polymerase chain reaction of mRNA from trigeminal ganglia indicated that all four EP prostanoid receptors were present. However, in both Type 1 and Type 2 cells the effects of PGE(2) were only mimicked by the selective EP(3) receptor agonist ONO-AE-248, and not by selective agonists for EP(1) (ONO-DI-004), EP(2) (ONO-AE1-259) and EP(4) (ONO-AE1-329) receptors. These data indicate that two populations of neurons in trigeminal ganglia differing in their calcium channel expression, sensitivity to mu-opioids and capsaicin also have divergent mechanisms of PGE(2)-mediated inhibition of calcium channels, with Gi/Go type G proteins involved in one population, and Gs type G proteins in the other.

  16. Acute insulin-induced elevations of circulating leptin and feeding inhibition in lean but not obese rats.

    PubMed

    Singh, Kimberly A; Boozer, Carol N; Vasselli, Joseph R

    2005-08-01

    Insulin has been shown to stimulate leptin mRNA expression acutely in rat adipose tissue, but its short-term effects on circulating leptin levels, and subsequent feeding behavior, have not been well described. We used 11-mo-old female selectively bred obesity-resistant (OR) and obesity-prone (OP) Sprague-Dawley rats maintained on laboratory chow to investigate this question. At testing, body weights and basal leptin levels of the OP rats were significantly elevated compared with the OR rats. In the 3-h fasted state, injection of 2.0 U insulin/kg ip resulted in significant elevations of plasma leptin at 4 h postinjection in both OP and OR groups (hour 4, +2.50 and +5.98 ng/ml, respectively). In separate feeding tests with the same groups, intake of laboratory chow pellets was significantly inhibited during hours 2-4 after 2.0 U/kg of insulin in the OR (-80.1%, P < 0.05), but not in the OP group, compared with intake after saline injections. In feeding tests with palatable moderately high-fat pellets after 2.0 and 3.0 U insulin/kg ip, significant decreases between hours 2 and 4 in intake were seen in the OR group only (-41.0 and -68.3%, respectively). Thus feeding inhibition coincides with insulin-induced elevations of plasma leptin in lean but not obese Sprague-Dawley rats. Our data suggest that elevations of leptin within the physiological range may contribute to short-term inhibition of food intake in rats and that this process may be stimulated by feeding-related insulin release.

  17. Pharmacologic treatment of impotence.

    PubMed

    Malloy, T R; Malkowicz, B

    1987-05-01

    A discussion of the anatomy, neurophysiology, endocrinology, and organ pharmacology pertinent to erectile function is presented, highlighting recent innovations in the pharmacologic treatment of impotence. Both oral and intracorporal pharmacologic agents that affect erectile dysfunction are discussed.

  18. Systems Pharmacology

    PubMed Central

    Boran, Aislyn D. W.; Iyengar, Ravi

    2011-01-01

    We examine how physiology and pathophysiology are studied from a systems perspective, using high-throughput experiments and computational analysis of regulatory networks. We describe the integration of these analyses with pharmacology, which leads to new understanding of drug action and enables drug discovery for complex diseases. Network studies of drug-target relationships can serve as an indication on the general trends in the approved drugs and the drug-discovery progress. There is a growing number of targeted therapies approved and in the pipeline, which meets a new set of problems with efficacy and adverse effects. The pitfalls of these mechanistically based drugs are described, along with how a systems view of drug action is increasingly important to uncover intricate signaling mechanisms that play an important part in drug action, resistance mechanisms, and off-target effects. Computational methodologies enable the classification of drugs according to their structures and to which proteins they bind. Recent studies have combined the structural analyses with analysis of regulatory networks to make predictions about the therapeutic effects of drugs for complex diseases and possible off-target effects. PMID:20687178

  19. A comparison of the potency of trimedoxime and other currently available oximes to reactivate tabun-inhibited acetylcholinesterase and eliminate acute toxic effects of tabun.

    PubMed

    Kassa, Jirí; Kuca, Kamil; Cabal, Jirí

    2005-12-01

    Tabun (O-ethyl-N,N-dimethyl phosphoramidocyanidate) belongs to highly toxic organophosphorus compounds misused as chemical warfare agents for military as well as terroristic purposes. It differs from other highly toxic organophosphates by its chemical structure and by the fact that tabun-inhibited acetylcholinesterase is extraordinarily difficult to reactivate. The potency of trimedoxime and other commonly used oximes (pralidoxime, obidoxime, the oxime HI-6) to reactivate tabun-inhibited acetylcholinesterase and to eliminate tabun-induced acute effects was evaluated using in vitro and in vivo methods. In vitro calculated kinetic parameters of reactivation of tabun-inhibited acetylcholinesterase from rat brain homogenate and in vivo determined percentage of reactivation of tabun-inhibited blood and tissue acetylcholinesterase in poisoned rats show that trimedoxime seems to be the most efficacious reactivator in the case of tabun poisonings. Trimedoxime was also found to be the most efficacious oxime in the elimination of acute lethal toxic effects in tabun-poisoned rats and mice. The oxime HI-6, so efficacious against soman, does not seem to be sufficiently effective oxime to reactivate tabun-inhibited acetylcholinesterase and to counteract acute lethal effects of tabun.

  20. Water-Filtered Infrared A Irradiation in Combination with Visible Light Inhibits Acute Chlamydial Infection

    PubMed Central

    Marti, Hanna; Koschwanez, Maria; Pesch, Theresa; Blenn, Christian; Borel, Nicole

    2014-01-01

    New therapeutic strategies are needed to overcome drawbacks in treatment of infections with intracellular bacteria. Chlamydiaceae are Gram-negative bacteria implicated in acute and chronic diseases such as abortion in animals and trachoma in humans. Water-filtered infrared A (wIRA) is short wavelength infrared radiation with a spectrum ranging from 780 to 1400 nm. In clinical settings, wIRA alone and in combination with visible light (VIS) has proven its efficacy in acute and chronic wound healing processes. This is the first study to demonstrate that wIRA irradiation combined with VIS (wIRA/VIS) diminishes recovery of infectious elementary bodies (EBs) of both intra- and extracellular Chlamydia (C.) in two different cell lines (Vero, HeLa) regardless of the chlamydial strain (C. pecorum, C. trachomatis serovar E) as shown by indirect immunofluorescence and titration by subpassage. Moreover, a single exposure to wIRA/VIS at 40 hours post infection (hpi) led to a significant reduction of C. pecorum inclusion frequency in Vero cells and C. trachomatis in HeLa cells, respectively. A triple dose of irradiation (24, 36, 40 hpi) during the course of C. trachomatis infection further reduced chlamydial inclusion frequency in HeLa cells without inducing the chlamydial persistence/stress response, as ascertained by electron microscopy. Irradiation of host cells (HeLa, Vero) neither affected cell viability nor induced any molecular markers of cytotoxicity as investigated by Alamar blue assay and Western blot analysis. Chlamydial infection, irradiation, and the combination of both showed a similar release pattern of a subset of pro-inflammatory cytokines (MIF/GIF, Serpin E1, RANTES, IL-6, IL-8) and chemokines (IL-16, IP-10, ENA-78, MIG, MIP-1α/β) from host cells. Initial investigation into the mechanism indicated possible thermal effects on Chlamydia due to irradiation. In summary, we demonstrate a non-chemical reduction of chlamydial infection using the combination of water

  1. Electrolyzed-reduced water inhibits acute ethanol-induced hangovers in Sprague-Dawley rats.

    PubMed

    Park, Seung-Kyu; Qi, Xu-Feng; Song, Soon-Bong; Kim, Dong-Heui; Teng, Yung-Chien; Yoon, Yang-Suk; Kim, Kwang-Yong; Li, Jian-Hong; Jin, Dan; Lee, Kyu-Jae

    2009-10-01

    Ethanol consumption disturbs the balance between the pro- and anti-oxidant systems of the organism, leading to oxidative stress. Electrolyzed-reduced water (ERW) is widely used by people in East Asia for drinking purposes because of its therapeutic properties including scavenging effect of reactive oxygen species. This study was performed to investigate the effect of ERW on acute ethanol-induced hangovers in Sprague-Dawley rats. Alcohol concentration in serum of ERW-treated rats showed significant difference at 1 h, 3 h and 5 h respectively as compared with the rats treated with distilled water. Both alcohol dehydrogenase type 1 and acetaldehyde dehydrogenase related with oxidation of alcohol were significantly increased in liver tissue while the level of aspartate aminotransferase and alanine aminotransferase in serum was markedly decreased 24 h after pre-oral administration of ERW. Moreover, oral administration of ERW significantly activated non-ezymatic (glutathione) and enzymatic (glutathione peroxidase, glutathione-S-transferase, Cu/Zn-superoxide dismutase and catalase) antioxidants in liver tissues compared with the control group. These results suggest that drinking ERW has an effect of alcohol detoxification by antioxidant mechanism and has potentiality for relief of ethanol-induced hangover symptoms.

  2. Response inhibition and serotonin in autism: a functional MRI study using acute tryptophan depletion.

    PubMed

    Daly, Eileen; Ecker, Christine; Hallahan, Brian; Deeley, Quinton; Craig, Michael; Murphy, Clodagh; Johnston, Patrick; Spain, Debbie; Gillan, Nicola; Gudbrandsen, Maria; Brammer, Michael; Giampietro, Vincent; Lamar, Melissa; Page, Lisa; Toal, Fiona; Schmitz, Nicole; Cleare, Anthony; Robertson, Dene; Rubia, Katya; Murphy, Declan G M

    2014-09-01

    It has been suggested that the restricted, stereotyped and repetitive behaviours typically found in autism are underpinned by deficits of inhibitory control. The biological basis of this is unknown but may include differences in the modulatory role of neurotransmitters, such as serotonin, which are implicated in the condition. However, this has never been tested directly. We therefore assessed the modifying role of serotonin on inhibitory brain function during a Go/No-Go task in 14 adults with autism and normal intelligence and 14 control subjects that did not differ in gender, age and intelligence. We undertook a double-blind, placebo-controlled, crossover trial of acute tryptophan depletion using functional magnetic resonance imaging. Following sham, adults with autism relative to controls had reduced activation in key inhibitory regions of inferior frontal cortex and thalamus, but increased activation of caudate and cerebellum. However, brain activation was modulated in opposite ways by depletion in each group. Within autistic individuals depletion upregulated fronto-thalamic activations and downregulated striato-cerebellar activations toward control sham levels, completely 'normalizing' the fronto-cerebellar dysfunctions. The opposite pattern occurred in controls. Moreover, the severity of autism was related to the degree of differential modulation by depletion within frontal, striatal and thalamic regions. Our findings demonstrate that individuals with autism have abnormal inhibitory networks, and that serotonin has a differential, opposite, effect on them in adults with and without autism. Together these factors may partially explain the severity of autistic behaviours and/or provide a novel (tractable) treatment target.

  3. Pharmacological inhibition of Polo-like kinase 1 (PLK1) by BI-2536 decreases the viability and survival of hamartin and tuberin deficient cells via induction of apoptosis and attenuation of autophagy.

    PubMed

    Valianou, Matthildi; Cox, Andrew M; Pichette, Benjamin; Hartley, Shannon; Paladhi, Unmesha Roy; Astrinidis, Aristotelis

    2015-01-01

    The mechanistic target of rapamycin complex 1 (mTORC1) increases translation, cell size and angiogenesis, and inhibits autophagy. mTORC1 is negatively regulated by hamartin and tuberin, the protein products of the tumor suppressors TSC1 and TSC2 that are mutated in Tuberous Sclerosis Complex (TSC) and sporadic Lymphangioleiomyomatosis (LAM). Hamartin interacts with the centrosomal and mitotic kinase polo-like kinase 1 (PLK1). Hamartin and tuberin deficient cells have abnormalities in centrosome duplication, mitotic progression, and cytokinesis, suggesting that the hamartin/tuberin heterodimer and mTORC1 signaling are involved in centrosome biology and mitosis. Here we report that PLK1 protein levels are increased in hamartin and tuberin deficient cells and LAM patient-derived specimens, and that this increase is rapamycin-sensitive. Pharmacological inhibition of PLK1 by the small-molecule inhibitor BI-2536 significantly decreased the viability and clonogenic survival of hamartin and tuberin deficient cells, which was associated with increased apoptosis. BI-2536 increased p62, LC3B-I and GFP-LC3 punctae, and inhibited HBSS-induced degradation of p62, suggesting that PLK1 inhibition attenuates autophagy. Finally, PLK1 inhibition repressed the expression and protein levels of key autophagy genes and proteins and the protein levels of Bcl(-)2 family members, suggesting that PLK1 regulates both autophagic and apoptotic responses. Taken together, our data point toward a previously unrecognized role of PLK1 on the survival of cells with mTORC1 hyperactivation, and the potential use of PLK1 inhibitors as novel therapeutics for tumors with dysregulated mTORC1 signaling, including TSC and LAM.

  4. Frontline Science: ATF3 is responsible for the inhibition of TNF-α release and the impaired migration of acute ethanol-exposed monocytes and macrophages.

    PubMed

    Hu, Chaojie; Meng, Xiaoming; Huang, Cheng; Shen, Chenlin; Li, Jun

    2017-03-01

    Binge drinking represses host innate immunity and leads to a high risk of infection. Acute EtOH-pretreated macrophages exhibit a decreased production of proinflammatory mediators in response to LPS. ATF3 is induced and counter-regulates the LPS/TLR4 inflammatory cascade. Here, we investigated the potential role of ATF3 in LPS tolerance in acute ethanol-pretreated macrophages. We found that there was an inverse correlation between ATF3 and LPS-induced TNF-α production in acute ethanol-pretreated murine monocytes and macrophages. The knockdown of ATF3 attenuated the inhibitory effects of acute ethanol treatment on LPS-induced TNF-α production. Furthermore, ChIP assays and co-IP demonstrated that ATF3, together with HDAC1, negatively modulated the transcription of TNF-α. In binge-drinking mice challenged with LPS, an up-regulation of ATF3 and HDAC1 and a concomitant decrease in TNF-α were observed. Given that HDAC1 was concomitantly induced in acute ethanol-exposed monocytes and macrophages, we used the HDACi TSA or silenced HDAC1 to explore the role of HDAC1 in acute ethanol-treated macrophages. Our results revealed that TSA treatment and HDAC1 knockdown prevented acute ethanol-induced ATF3 expression and the inhibition of TNF-α transcription. These data indicated a dual role for HDAC1 in acute ethanol-induced LPS tolerance. Furthermore, we showed that the induction of ATF3 led to the impaired migration of BM monocytes and macrophages. Overall, we present a novel role for ATF3 in the inhibition of LPS-induced TNF-α and in the impairment of monocyte and macrophage migration.

  5. Targeting pro-inflammatory cytokines following joint injury: acute intra-articular inhibition of interleukin-1 following knee injury prevents post-traumatic arthritis

    PubMed Central

    2014-01-01

    Introduction Post-traumatic arthritis (PTA) is a progressive, degenerative response to joint injury, such as articular fracture. The pro-inflammatory cytokines, interleukin 1(IL-1) and tumor necrosis factor alpha (TNF-α), are acutely elevated following joint injury and remain elevated for prolonged periods post-injury. To investigate the role of local and systemic inflammation in the development of post-traumatic arthritis, we targeted both the initial acute local inflammatory response and a prolonged 4 week systemic inflammatory response by inhibiting IL-1 or TNF-α following articular fracture in the mouse knee. Methods Anti-cytokine agents, IL-1 receptor antagonist (IL-1Ra) or soluble TNF receptor II (sTNFRII), were administered either locally via an acute intra-articular injection or systemically for a prolonged 4 week period following articular fracture of the knee in C57BL/6 mice. The severity of arthritis was then assessed at 8 weeks post-injury in joint tissues via histology and micro computed tomography, and systemic and local biomarkers were assessed in serum and synovial fluid. Results Intra-articular inhibition of IL-1 significantly reduced cartilage degeneration, synovial inflammation, and did not alter bone morphology following articular fracture. However, systemic inhibition of IL-1, and local or systemic inhibition of TNF provided no benefit or conversely led to increased arthritic changes in the joint tissues. Conclusion These results show that intra-articular IL-1, rather than TNF-α, plays a critical role in the acute inflammatory phase of joint injury and can be inhibited locally to reduce post-traumatic arthritis following a closed articular fracture. Targeted local inhibition of IL-1 following joint injury may represent a novel treatment option for PTA. PMID:24964765

  6. Methamphetamine acutely inhibits voltage-gated calcium channels but chronically up-regulates L-type channels.

    PubMed

    Andres, Marilou A; Cooke, Ian M; Bellinger, Frederick P; Berry, Marla J; Zaporteza, Maribel M; Rueli, Rachel H; Barayuga, Stephanie M; Chang, Linda

    2015-07-01

    In neurons, calcium (Ca(2+) ) channels regulate a wide variety of functions ranging from synaptic transmission to gene expression. They also induce neuroplastic changes that alter gene expression following psychostimulant administration. Ca(2+) channel blockers have been considered as potential therapeutic agents for the treatment of methamphetamine (METH) dependence because of their ability to reduce drug craving among METH users. Here, we studied the effects of METH exposure on voltage-gated Ca(2+) channels using SH-SY5Y cells as a model of dopaminergic neurons. We found that METH has different short- and long-term effects. A short-term effect involves immediate (< 5 min) direct inhibition of Ca(2+) ion movements through Ca(2+) channels. Longer exposure to METH (20 min or 48 h) selectively up-regulates the expression of only the CACNA1C gene, thus increasing the number of L-type Ca(2+) channels. This up-regulation of CACNA1C is associated with the expression of the cAMP-responsive element-binding protein (CREB), a known regulator of CACNA1C gene expression, and the MYC gene, which encodes a transcription factor that putatively binds to a site proximal to the CACNA1C gene transcription initiation site. The short-term inhibition of Ca(2+) ion movement and later, the up-regulation of Ca(2+) channel gene expression together suggest the operation of cAMP-responsive element-binding protein- and C-MYC-mediated mechanisms to compensate for Ca(2+) channel inhibition by METH. Increased Ca(2+) current density and subsequent increased intracellular Ca(2+) may contribute to the neurodegeneration accompanying chronic METH abuse. Methamphetamine (METH) exposure has both short- and long-term effects. Acutely, methamphetamine directly inhibits voltage-gated calcium channels. Chronically, neurons compensate by up-regulating the L-type Ca(2+) channel gene, CACNA1C. This compensatory mechanism is mediated by transcription factors C-MYC and CREB, in which CREB is linked to the

  7. The acute inhibition of rapid eye movement sleep by citalopram may impair spatial learning and passive avoidance in mice.

    PubMed

    Bridoux, A; Laloux, C; Derambure, P; Bordet, R; Monaca Charley, C

    2013-03-01

    Rapid eye movement (REM) sleep is known to be essential for memory. Hence, REM sleep deprivation impairs memory processes. The frequently prescribed selective serotonin reuptake inhibitors (SSRIs) are known to cause REM sleep deprivation and to impair cognitive performance in humans and rodents. We suggested that impaired memory processes by citalopram in C57/BL6 mice could be explained by the acute inhibition of REM sleep. We hypothesized that those acute citalopram 5 and 10 mg/kg injections induced REM sleep deprivation, altered cognitive performance in passive avoidance, impaired spatial memory compared to controls. Three experiments have been realized: (1) mice received successively physiological saline, injection of citalopram 5 and 10 mg/kg and were recorded by polysomnographic recording after each injection. (2) Cognitive performance was evaluated in the passive avoidance with two groups of mice. One group received citalopram before training and one, after training. (3) Spatial learning was evaluated with another group of animals in the Y-maze test. At 5 and 10 mg/kg, citalopram delayed REM sleep onset and decreased REM sleep amounts (vs. controls). The same doses were administrated in the passive avoidance test and have significantly shortened latency to enter the dark compartment. In the Y-maze, citalopram-treated mice showed a decreased percentage of time spent in the novel arm in contrast to the two other arms compared with controls. We showed that citalopram impaired cognitive performance in behavioral tasks. Those impairments could be linked to REM sleep deprivation induced by citalopram although causal relationship needs to be investigated in further studies.

  8. Taraxerol, a pentacyclic triterpene from Abroma augusta leaf, attenuates acute inflammation via inhibition of NF-κB signaling.

    PubMed

    Khanra, Ritu; Dewanjee, Saikat; Dua, Tarun K; Bhattacharjee, Niloy

    2017-04-01

    Abroma augusta L. (Malvaceae) leaf is traditionally used to treat inflammatory disorders. In our laboratory, we have scientifically validated the anti-inflammatory effect of A. augusta leaf extract. In this study, it has been aimed to evaluate in vivo anti-inflammatory effect of taraxerol isolated from the methanol extract of A. augusta leaf. It was further intended to find out the probable mechanism of anti-inflammatory effect of taraxerol. The anti-inflammatory effect of taraxerol (5 and 10mg/kg, i.p.) was measured employing carrageenan-induced paw edema model of acute inflammation. The carrageenan injection resulted significant edema formation in the right paw when compared with un-injected left paw. However, taraxerol (10mg/kg) treatment could significantly (p<0.05-0.01) attenuate carrageenan induced paw edema 2h onward. The effect of taraxerol at the dose of 5mg/kg was found to be significant (p<0.05) only after 4h of carrageenan treatment. Taraxerol (10mg/kg) treatment could significantly (p<0.01) attenuate carrageenan mediated up-regulation in the levels of IL 1β, IL 6, IL 12 and TNF α in the right paw tissues. In search of molecular mechanism, taraxerol (10mg/kg) could significantly (p<0.05-0.01) reinstate carrageenan provoked NF-κB signaling and thereby caused significant down-regulation in the expressions of COX-2 (p<0.01) and iNOS (p<0.05). In conclusion, taraxerol would attenuate acute inflammation via inhibition of NF-κB signaling.

  9. Attenuation of Acute Phase Injury in Rat Intracranial Hemorrhage by Cerebrolysin that Inhibits Brain Edema and Inflammatory Response.

    PubMed

    Yang, Yang; Zhang, Yan; Wang, Zhaotao; Wang, Shanshan; Gao, Mou; Xu, Ruxiang; Liang, Chunyang; Zhang, Hongtian

    2016-04-01

    The outcome of intracerebral hemorrhage (ICH) is mainly determined by the volume of the hemorrhage core and the secondary brain damage to penumbral tissues due to brain swelling, microcirculation disturbance and inflammation. The present study aims to investigate the protective effects of cerebrolysin on brain edema and inhibition of the inflammation response surrounding the hematoma core in the acute stage after ICH. The ICH model was induced by administration of type VII bacterial collagenase into the stratum of adult rats, which were then randomly divided into three groups: ICH + saline; ICH + Cerebrolysin (5 ml/kg) and sham. Cerebrolysin or saline was administered intraperitoneally 1 h post surgery. Neurological scores, extent of brain edema content and Evans blue dye extravasation were recorded. The levels of pro-inflammatory factors (IL-1β, TNF-α and IL-6) were assayed by Real-time PCR and Elisa kits. Aquaporin-4 (AQP4) and tight junction proteins (TJPs; claudin-5, occludin and zonula occluden-1) expression were measured at multiple time points. The morphological and intercellular changes were characterized by Electron microscopy. It is found that cerebrolysin (5 ml/kg) improved the neurological behavior and reduced the ipsilateral brain water content and Evans blue dye extravasation. After cerebrolysin treated, the levels of pro-inflammatory factors and AQP4 in the peri-hematomal areas were markedly reduced and were accompanied with higher expression of TJPs. Electron microscopy showed the astrocytic swelling and concentrated chromatin in the ICH group and confirmed the cell junction changes. Thus, early cerebrolysin treatment ameliorates secondary injury after ICH and promotes behavioral performance during the acute phase by reducing brain edema, inflammatory response, and blood-brain barrier permeability.

  10. Inhibition of hyaluronan synthesis in rats reduces renal ability to excrete fluid and electrolytes during acute hydration

    PubMed Central

    Stridh, Sara; Palm, Fredrik

    2013-01-01

    Background. Hyaluronan (HA) is the dominant glycosaminoglycan in the renomedullary interstitium. Renomedullary HA has been implicated in tubular fluid handling due to its water-attracting properties and the changes occurring in parallel to acute variations in the body hydration status. Methods. HA production was inhibited by 4-methylumbelliferone (4-MU in drinking water for 5 days, 1.45 ± 0.07 g/day/kg body weight) in rats prior to hydration. Results. Following hypotonic hydration for 135 min in control animals, diuresis and osmotic excretion increased while sodium excretion and glomerular filtration rate (GFR) remained unchanged. The medullary and cortical HA contents were 7.85 ± 1.29 ng/mg protein and 0.08 ± 0.01 ng/mg protein, respectively. Medullary HA content after 4-MU was 38% of that in controls (2.98 ± 0.95 ng/g protein, p < 0.05), while the low cortical levels were unaffected. Baseline urine flow was not different from that in controls. The diuretic response to hydration was, however, only 51% of that in controls (157 ± 36 versus 306 ± 54 µl/g kidney weight/135 min, p < 0.05) and the osmolar excretion only 47% of that in controls (174 ± 47 versus 374 ± 41 µOsm/g kidney weight/135 min, p < 0.05). Sodium excretion, GFR, and arterial blood pressure were similar to that in control rats and unaltered during hydration. Conclusions. Reduction of renomedullary interstitial HA using 4-MU reduces the ability of the kidney to respond appropriately upon acute hydration. The results strengthen the concept of renomedullary HA as a modulator of tubular fluid handling by changing the physicochemical properties of the interstitial space. PMID:24102146

  11. The pharmacological profile and clinical prospects of the oral 5-HT1F receptor agonist lasmiditan in the acute treatment of migraine

    PubMed Central

    Israel, Heike; Neeb, Lars

    2015-01-01

    More than 20 years have passed without the launch of a new substance class for acute migraine therapy. Triptans were the latest class of substances which successfully passed all developmental stages with a significant antimigraine efficacy and a sufficient safety profile. New drugs with a better adverse event profile and at least similar efficacy are needed for migraine subjects who cannot tolerate triptans for attack treatment. Lasmiditan is a novel highly specific 5-HT1F receptor agonist currently in clinical trials for acute migraine therapy and devoid of vasoconstriction in coronary arteries as determined in a surrogate assay. In both phase II randomized, placebo-controlled trials in acute migraine the primary endpoint was met. For the intravenous formulation a clear dose-dependent effect on headaches could be determined. Lasmiditan tablets in doses of 50–400 mg show significant headache relief after 2 hours compared with placebo and improved accompanying symptoms. This substance is chemically clearly different from other antimigraine drugs, which is also reflected by its dose-dependent adverse event profile chiefly including dizziness, vertigo, paresthesia and fatigue. Adverse events are usually linked to the central nervous system. Future phase III clinical trials with an active triptan comparator or in a preferential trial design will allow a better comparison of lasmiditan and triptans. They will also determine whether lasmiditan will become available to the migraine patient. PMID:25584073

  12. Berberine inhibits acute radiation intestinal syndrome in human with abdomen radiotherapy.

    PubMed

    Li, Guang-hui; Wang, Dong-lin; Hu, Yi-de; Pu, Ping; Li, De-zhi; Wang, Wei-dong; Zhu, Bo; Hao, Ping; Wang, Jun; Xu, Xian-qiong; Wan, Jiu-qing; Zhou, Yi-bing; Chen, Zheng-tang

    2010-09-01

    Radiation-induced acute intestinal symptoms (RIAISs) are the most relevant complication of abdominal or pelvic radiation. Considering the negative impact of RIAIS on patients' daily activities, the preventive effects of berberine on RIAIS in patients were investigated. Thirty-six patients with seminoma or lymphomas were randomized to receive berberine oral (n = 18) or not (n = 18). Forty-two patients with cervical cancer were randomized to a trial group (n = 21) and control group (n = 21). Radiotherapy used a parallel opposed anterior and posterior. 300-mg berberine was administered orally three times daily in trial groups. Eight patients with RIAIS were treated with 300-mg berberine three times daily from the third to the fifth week. Toxicities, such as fatigue, anorexia/nausea, etc., were graded weekly according to CTC version 2.0. Patients with abdominal/pelvic radiation in the control group showed grade 1 fatigue, anorexia/nausea, colitis, vomiting, proctitis, weight loss, diarrhea and grade 2 anorexia/nausea, fatigue. Only grade 1 colitis, anorexia/nausea, and fatigue were seen in patients of abdominal radiation treated with berberine. Grade 1 fatigue, colitis, anorexia/nausea, and proctitis occurred in patients of pelvic radiotherapy treated with berberine. Pretreatment with berberine significantly decreased the incidence and severity of RIAIS in patients with abdominal/pelvic radiotherapy when compared with the patients of the control group (P < 0.05). RIAIS were reduced in patients with abdominal radiotherapy/pelvic radiation after receiving berberine treatment. Berberine significantly reduced the incidence and severity of RIAIS and postponed the occurrence of RIAIS in patients with abdominal or whole pelvic radiation.

  13. Inhibition of myostatin signaling through Notch activation following acute resistance exercise.

    PubMed

    MacKenzie, Matthew G; Hamilton, David Lee; Pepin, Mark; Patton, Amy; Baar, Keith

    2013-01-01

    Myostatin is a TGFβ family member and negative regulator of muscle size. Due to the complexity of the molecular pathway between myostatin mRNA/protein and changes in transcription, it has been difficult to understand whether myostatin plays a role in resistance exercise-induced skeletal muscle hypertrophy. To circumvent this problem, we determined the expression of a unique myostatin target gene, Mighty, following resistance exercise. Mighty mRNA increased by 6 h (82.9 ± 24.21%) and remained high out to 48 h (56.5 ± 19.67%) after resistance exercise. Further examination of the soleus, plantaris and tibialis anterior muscles showed that the change in Mighty mRNA at 6 h correlated with the increase in muscle size associated with this protocol (R(2) = 0.9996). The increase in Mighty mRNA occurred both independent of Smad2 phosphorylation and in spite of an increase in myostatin mRNA (341.8 ± 147.14% at 3 h). The myostatin inhibitor SKI remained unchanged. However, activated Notch, another potential inhibitor of TGFβ signaling, increased immediately following resistance exercise (83 ± 11.2%) and stayed elevated out to 6 h (78 ± 16.6%). Electroportion of the Notch intracellular domain into the tibialis anterior resulted in an increase in Mighty mRNA (63 ± 13.4%) that was equivalent to the canonical Notch target HES-1 (94.4 ± 7.32%). These data suggest that acute resistance exercise decreases myostatin signaling through the activation of the TGFβ inhibitor Notch resulting in a decrease in myostatin transcriptional activity that correlates well with muscle hypertrophy.

  14. Diethylcarbamazine inhibits NF-κB activation in acute lung injury induced by carrageenan in mice.

    PubMed

    Santos, Laise Aline Martins; Ribeiro, Edlene Lima; Barbosa, Karla Patrícia Sousa; Fragoso, Ingrid Tavares; Gomes, Fabiana Oliveira Dos Santos; Donato, Mariana Aragão Matos; Silva, Bruna Santos; Silva, Amanda Karolina Soares; Rocha, Sura Wanessa Santos; França, Maria Eduarda Rocha; Rodrigues, Gabriel Barros; Silva, Teresinha Gonçalves; Peixoto, Christina Alves

    2014-11-01

    Diethylcarbamazine citrate (DEC) is widely used to treat lymphatic filariasis and Tropical Pulmonary Eosinophilia. A number of studies have reported a possible role in the host immune system, but exactly how DEC exerts this effect is still unknown. The present study reports the effects of DEC pretreatment on NF-κB regulation using the pleurisy model induced by carrageenan. Swiss male mice (Mus musculus) were divided into four experimental groups: control (SAL); carrageenan (CAR); diethylcarbamazine (DEC) and curcumin (CUR). The animals were pretreated with DEC (50mg/kg, v.o), CUR (50mg/kg, i.p) or distilled water for three consecutive days before pleurisy. One way analysis of variance (ANOVA) was performed by Tukey post-hoc test, and values were considered statistically significant when p<0.05. DEC pretreatment reduced tissue damage and the production of inflammatory markers, such as NO, iNOS, PGE2, COX-2, and PARP induced by carrageenan. Similarly, a known inhibitor of NF-κB pathway (curcumin) was also able to reduce these parameters. Like curcumin, DEC prevents NF-κB activation by reducing NF-κB p65 phosphorylation and IκBα degradation. DEC prevented NF-κB activation via p38 MAPK, but did not interfere in the ERK pathway in this experimental model. However, further studies should be developed to confirm this hypothesis. These findings suggest that DEC could be a promising drug for inflammatory disorders, especially in pulmonary diseases such as Acute Lung Inflammation, due its high anti-inflammatory potential which prevents NF-κB activation.

  15. Pharmacological Inhibition of c-Jun N-terminal Kinase Reduces Food Intake and Sensitizes Leptin’s Anorectic Signaling Actions

    PubMed Central

    Gao, Su; Howard, Shannon; LoGrasso, Philip V.

    2017-01-01

    The role for c-Jun N-terminal Kinase (JNK) in the control of feeding and energy balance is not well understood. Here, by use of novel and highly selective JNK inhibitors, we investigated the actions of JNK in the control of feeding and body weight homeostasis. In lean mice, intraperitoneal (i.p.) or intracerebroventricular (i.c.v.) administration of SR-3306, a brain-penetrant and selective pan-JNK (JNK1/2/3) inhibitor, reduced food intake and body weight. Moreover, i.p. and i.c.v. administrations of SR11935, a brain-penetrant and JNK2/3 isoform-selective inhibitor, exerted similar anorectic effects as SR3306, which suggests JNK2 or JNK3 mediates aspect of the anorectic effect by pan-JNK inhibition. Furthermore, daily i.p. injection of SR3306 (7 days) prevented the increases in food intake and weight gain in lean mice upon high-fat diet feeding, and this injection paradigm reduced high-fat intake and obesity in diet-induced obese (DIO) mice. In the DIO mice, JNK inhibition sensitized leptin’s anorectic effect, and enhanced leptin-induced STAT3 activation in the hypothalamus. The underlying mechanisms likely involve the downregulation of SOCS3 by JNK inhibition. Collectively, our data suggest that JNK activity promotes positive energy balance, and the therapeutic intervention inhibiting JNK activities represents a promising approach to ameliorate diet-induced obesity and leptin resistance. PMID:28165482

  16. Inhibition of CD34+ cell migration by matrix metalloproteinase-2 during acute myocardial ischemia, counteracted by ischemic preconditioning

    PubMed Central

    Lukovic, Dominika; Zlabinger, Katrin; Gugerell, Alfred; Spannbauer, Andreas; Pavo, Noemi; Mandic, Ljubica; Weidenauer, Denise T.; Kastl, Stefan; Kaun, Christoph; Posa, Aniko; Sabdyusheva Litschauer, Inna; Winkler, Johannes; Gyöngyösi, Mariann

    2017-01-01

    Background. Mobilization of bone marrow-origin CD34+ cells was investigated 3 days (3d) after acute myocardial infarction (AMI) with/without ischemic preconditioning (IP) in relation to stromal-derived factor-1 (SDF-1α)/ chemokine receptor type 4 (CXCR4) axis, to search for possible mechanisms behind insufficient cardiac repair in the first days post-AMI.  Methods. Closed-chest reperfused AMI was performed by percutaneous balloon occlusion of the mid-left anterior descending (LAD) coronary artery for 90min, followed by reperfusion in pigs. Animals were randomized to receive either IP initiated by 3x5min cycles of re-occlusion/re-flow prior to AMI (n=6) or control AMI (n=12). Blood samples were collected at baseline, 3d post-AMI, and at 1-month follow-up to analyse chemokines and mobilized CD34+ cells. To investigate the effect of acute hypoxia, SDF-1α and matrix metalloproteinase (MMP)-2 in vitro were assessed, and a migration assay of CD34+ cells toward cardiomyocytes was performed.  Results. Reperfused AMI induced significant mobilisation of CD34+ cells (baseline: 260±75 vs. 3d: 668±180; P<0.001) and secretion of MMP-2 (baseline: 291.83±53.40 vs. 3d: 369.64±72.89; P=0.011) into plasma, without affecting the SDF-1α concentration. IP led to the inhibition of MMP-2 (IP: 165.67±47.99 vs. AMI: 369.64±72.89; P=0.004) 3d post-AMI, accompanied by increased release of SDF-1α (baseline: 23.80±12.36 vs. 3d: 45.29±11.31; P=0.05) and CXCR4 (baseline: 0.59±0.16 vs. 3d: 2.06±1.42; P=0.034), with a parallel higher level of mobilisation of CD34+ cells (IP: 881±126 vs. AMI: 668±180; P=0.026), compared to non-conditioned AMI. In vitro, CD34+ cell migration toward cardiomyocytes was enhanced by SDF-1α, which was completely abolished by 90min hypoxia and co-incubation with MMP-2.  Conclusions. Non-conditioned AMI induces MMP-2 release, hampering the ischemia-induced increase in SDF-1α and CXCR4 by cleaving the SDF-1α/CXCR4 axis, with diminished mobilization of

  17. The pharmacology of topical analgesics.

    PubMed

    Barkin, Robert L

    2013-07-01

    Pain management of patients continues to pose challenges to clinicians. Given the multiple dimensions of pain--whether acute or chronic, mild, moderate, or severe, nociceptive or neuropathic--a multimodal approach may be needed. Fortunately, clinicians have an array of nonpharmacologic and pharmacologic treatment choices; however, each modality must be chosen carefully, because some often used oral agents are associated with safety and tolerability issues that restrict their use in certain patients. In particular, orally administered nonsteroidal antiinflammatory drugs, opioids, antidepressants, and anticonvulsants are known to cause systemic adverse effects in some patients. To address this problem, a number of topical therapies in various therapeutic classes have been developed to reduce systemic exposure and minimize the risks of patients developing adverse events. For example, topical nonsteroidal anti-inflammatory drug formulations produce a site-specific effect (ie, cyclo-oxygenase inhibition) while decreasing the systemic exposure that may lead to undesired effects in patients. Similarly, derivatives of acetylsalicylic acid (ie, salicylates) are used in topical analgesic formulations that do not significantly enter the patient's systemic circulation. Salicylates, along with capsaicin, menthol, and camphor, compose the counterirritant class of topical analgesics, which produce analgesia by activating and then desensitizing epidermal nociceptors. Additionally, patches and creams that contain the local anesthetic lidocaine, alone or co-formulated with other local anesthetics, are also used to manage patients with select acute and chronic pain states. Perhaps the most common topical analgesic modality is the cautious application of cutaneous cold and heat. Such treatments may decrease pain not by reaching the target tissue through systemic distribution, but by acting more directly on the affected tissue. Despite the tolerability benefits associated with avoiding

  18. Acute withdrawal from repeated cocaine treatment enhances latent inhibition of a conditioned fear response.

    PubMed

    Murphy, C A; Heidbreder, C; Feldon, J

    2001-02-01

    Psychostimulant-induced locomotor sensitization and disrupted latent inhibition (LI) of a classically conditioned association are two paradigms that have been widely studied as animal behavioural models of psychosis. In this study we assessed the effects of withdrawal from the repeated intermittent administration of cocaine on LI of a conditioned fear response. Animals which were either preexposed (PE) to a tone conditioned stimulus (CS) or naive to the tone (i.e. non-preexposed: NPE) subsequently experienced 10 pairings of the tone CS with footshock. Afterwards, both groups received five daily injections of cocaine (20 mg/kg, i.p.) or saline. After 3 days of withdrawal from drug treatment, animals were tested for conditioned freezing to the context of the footshock chamber, and 1 day later, for conditioned freezing to the tone CS. Cocaine-sensitized animals exhibited markedly enhanced LI compared to saline-treated animals, due to the fact that NPE-cocaine animals spent more time freezing during the tone CS than NPE-saline animals, whereas PE-cocaine animals showed a tendency toward reduced freezing compared to the saline groups. While these results suggest the presence of increased anxiety in cocaine-withdrawn NPE animals, the absence of this effect in cocaine-withdrawn PE rats indicates that cocaine withdrawal also influences the retrieval of previously learned information.

  19. Cyclic strain inhibits acute pro-inflammatory gene expression in aortic valve interstitial cells.

    PubMed

    Smith, Kathryn E; Metzler, Scott A; Warnock, James N

    2010-02-01

    Mechanical in vitro preconditioning of tissue engineered heart valves is viewed as an essential process for tissue development prior to in vivo implantation. However, a number of pro-inflammatory genes are mechanosensitive and their elaboration could elicit an adverse response in the host. We hypothesized that the application of normal physiological levels of strain to isolated valve interstitial cells would inhibit the expression of pro-inflammatory genes. Cells were subjected to 0, 5, 10, 15 and 20% strain. Expression of VCAM-1, MCP-1, GM-CSF and OPN was then measured using qRT-PCR. With the exception of OPN, all genes were significantly up regulated when no strain was applied. MCP-1 expression was significantly lower in the presence of strain, although strain magnitude did not affect the expression level. VCAM-1 and GM-CSF had the lowest expression levels at 15% strain, which represent normal physiological conditions. These findings were confirmed using confocal microscopy. Additionally, pSMAD 2/3 and IkappaBalpha expression were imaged to elucidate potential mechanisms of gene expression. Data showed that 15% strain increased pSMAD 2/3 expression and prevented phosphorylation of IkappaBalpha. In conclusion, cyclic strain reduces expression of pro-inflammatory genes, which may be beneficial for the in vitro pre-conditioning of tissue engineered heart valves.

  20. Inhibiting PLK1 induces autophagy of acute myeloid leukemia cells via mammalian target of rapamycin pathway dephosphorylation.

    PubMed

    Tao, Yan-Fang; Li, Zhi-Heng; Du, Wei-Wei; Xu, Li-Xiao; Ren, Jun-Li; Li, Xiao-Lu; Fang, Fang; Xie, Yi; Li, Mei; Qian, Guang-Hui; Li, Yan-Hong; Li, Yi-Ping; Li, Gang; Wu, Yi; Feng, Xing; Wang, Jian; He, Wei-Qi; Hu, Shao-Yan; Lu, Jun; Pan, Jian

    2017-03-01

    Decreased autophagy is accompanied by the development of a myeloproliferative state or acute myeloid leukemia (AML). AML cells are often sensitive to autophagy‑inducing stimuli, prompting the idea that targeting autophagy can be useful in AML cytotoxic therapy. AML NB4 cells overexpressing microtubule-associated protein 1 light chain 3-green fluorescent protein were screened with 69 inhibitors to analyze autophagy activity. AML cells were treated with the polo-like kinase 1 (PLK1) inhibitors RO3280 and BI2536 before autophagy analysis. Cleaved LC3 (LC3-II) and the phosphorylation of mammalian target of rapamycin (mTOR), adenosine monophosphate-activated protein kinase, and Unc-51-like kinase 1 during autophagy was detected with western blotting. Autophagosomes were detected using transmission electron microscopy. Several inhibitors had promising autophagy inducer effects: BI2536, MLN0905, SK1-I, SBE13 HCL and RO3280. Moreover, these inhibitors all targeted PLK1. Autophagy activity was increased in the NB4 cells treated with RO3280 and BI2536. Inhibition of PLK1 expression in NB4, K562 and HL-60 leukemia cells with RNA interference increased LC3-II and autophagy activity. The phosphorylation of mTOR was reduced significantly in NB4 cells treated with RO3280 and BI2536, and was also reduced significantly when PLK1 expression was downregulated in the NB4, K562 and HL-60 cells. We demonstrate that PLK1 inhibition induces AML cell autophagy and that it results in mTOR dephosphorylation. These results may provide new insights into the molecular mechanism of PLK1 in regulating autophagy.

  1. Inhibiting PLK1 induces autophagy of acute myeloid leukemia cells via mammalian target of rapamycin pathway dephosphorylation

    PubMed Central

    Tao, Yan-Fang; Li, Zhi-Heng; Du, Wei-Wei; Xu, Li-Xiao; Ren, Jun-Li; Li, Xiao-Lu; Fang, Fang; Xie, Yi; Li, Mei; Qian, Guang-Hui; Li, Yan-Hong; Li, Yi-Ping; Li, Gang; Wu, Yi; Feng, Xing; Wang, Jian; He, Wei-Qi; Hu, Shao-Yan; Lu, Jun; Pan, Jian

    2017-01-01

    Decreased autophagy is accompanied by the development of a myeloproliferative state or acute myeloid leukemia (AML). AML cells are often sensitive to autophagy-inducing stimuli, prompting the idea that targeting autophagy can be useful in AML cytotoxic therapy. AML NB4 cells overexpressing microtubule-associated protein 1 light chain 3-green fluorescent protein were screened with 69 inhibitors to analyze autophagy activity. AML cells were treated with the polo-like kinase 1 (PLK1) inhibitors RO3280 and BI2536 before autophagy analysis. Cleaved LC3 (LC3-II) and the phosphorylation of mammalian target of rapamycin (mTOR), adenosine monophosphate-activated protein kinase, and Unc-51-like kinase 1 during autophagy was detected with western blotting. Autophagosomes were detected using transmission electron microscopy. Several inhibitors had promising autophagy inducer effects: BI2536, MLN0905, SK1-I, SBE13 HCL and RO3280. Moreover, these inhibitors all targeted PLK1. Autophagy activity was increased in the NB4 cells treated with RO3280 and BI2536. Inhibition of PLK1 expression in NB4, K562 and HL-60 leukemia cells with RNA interference increased LC3-II and autophagy activity. The phosphorylation of mTOR was reduced significantly in NB4 cells treated with RO3280 and BI2536, and was also reduced significantly when PLK1 expression was downregulated in the NB4, K562 and HL-60 cells. We demonstrate that PLK1 inhibition induces AML cell autophagy and that it results in mTOR dephosphorylation. These results may provide new insights into the molecular mechanism of PLK1 in regulating autophagy. PMID:28184925

  2. Effects of p38α/β inhibition on acute lymphoblastic leukemia proliferation and survival in vivo

    PubMed Central

    Alsadeq, A; Strube, S; Krause, S; Carlet, M; Jeremias, I; Vokuhl, C; Loges, S; Aguirre-Ghiso, JA; Trauzold, A; Cario, G; Stanulla, M; Schrappe, M; Schewe, DM

    2017-01-01

    P38α/β has been described as a tumor-suppressor controlling cell cycle checkpoints and senescence in epithelial malignancies. However, p38α/β also regulates other cellular processes. Here, we describe a role of p38α/β as a regulator of acute lymphoblastic leukemia (ALL) proliferation and survival in experimental ALL models. We also report first evidence that p38α/β phosphorylation is associated with the occurrence of relapses in TEL-AML1-positive leukemia. First, in vitro experiments show that p38α/β signaling is induced in a cyclical manner upon initiation of proliferation and remains activated during log-phase of cell growth. Next, we provide evidence that growth-permissive signals in the bone marrow activate p38α/β in a novel avian ALL model, in which therapeutic targeting can be tested. We further demonstrate that p38α/β inhibition by small molecules can suppress leukemic expansion and prolong survival of mice bearing ALL cell lines and primary cells. Knockdown of p38α strongly delays leukemogenesis in mice xenografted with cell lines. Finally, we show that in xenografted TEL-AML1 patients, ex vivo p38α/β phosphorylation is associated with an inferior long-term relapse-free survival. We propose p38α/β as a mediator of proliferation and survival in ALL and show first preclinical evidence for p38α/β inhibition as an adjunct approach to conventional therapies. PMID:26104660

  3. MicroRNAs mediate the cardioprotective effect of angiotensin-converting enzyme inhibition in acute kidney injury.

    PubMed

    Rana, Indrajeetsinh; Velkoska, Elena; Patel, Sheila K; Burrell, Louise M; Charchar, Fadi J

    2015-12-01

    Cardiovascular disease, including cardiac hypertrophy, is common in patients with kidney disease and can be partially attenuated using blockers of the renin-angiotensin system (RAS). It is unknown whether cardiac microRNAs contribute to the pathogenesis of cardiac hypertrophy or to the protective effect of RAS blockade in kidney disease. Using a subtotal nephrectomy rat model of kidney injury, we investigated changes in cardiac microRNAs that are known to have direct target genes involved in the regulation of apoptosis, fibrosis, and hypertrophy. The effect of treatment with the angiotensin-converting enzyme (ACE) inhibitor ramipril on cardiac microRNAs was also investigated. Kidney injury led to a significant increase in cardiac microRNA-212 and microRNA-132 expression. Ramipril reduced cardiac hypertrophy, attenuated the increase in microRNA-212 and microRNA-132, and significantly increased microRNA-133 and microRNA-1 expression. There was altered expression of caspase-9, B cell lymphoma-2, transforming growth factor-β, fibronectin 1, collagen type 1A1, and forkhead box protein O3, which are all known to be involved in the regulation of apoptosis, fibrosis, and hypertrophy in cardiac cells while being targets for the above microRNAs. ACE inhibitor treatment increased expression of microRNA-133 and microRNA-1. The inhibitory action of ACE inhibitor treatment on increased cardiac NADPH oxidase isoform 1 expression after subtotal nephrectomy surgery suggests that inhibition of oxidative stress is also one of mechanism of ACE inhibitor-mediated cardioprotection. These finding suggests the involvement of microRNAs in the cardioprotective action of ACE inhibition in acute renal injury, which is mediated through an inhibitory action on profibrotic and proapoptotic target genes and stimulatory action on antihypertrophic and antiapoptotic target genes.

  4. Nongenomic effects of cisplatin: acute inhibition of mechanosensitive transporters and channels without actin remodeling.

    PubMed

    Milosavljevic, Nina; Duranton, Christophe; Djerbi, Nadir; Puech, Pierre Henri; Gounon, Pierre; Lagadic-Gossmann, Dominique; Dimanche-Boitrel, Marie Thérèse; Rauch, Cyril; Tauc, Michel; Counillon, Laurent; Poët, Mallorie

    2010-10-01

    Cisplatin is an antineoplastic drug, mostly documented to cause cell death through the formation of DNA adducts. In patients, it exhibits a range of short-term side effects that are unlikely to be related to its genomic action. As cisplatin has been shown to modify membrane properties in different cell systems, we investigated its effects on mechanosensitive ion transporters and channels. We show here that cisplatin is a noncompetitive inhibitor of the mechanosensitive Na(+)/H(+) exchanger NHE-1, with a half-inhibition concentration of 30 μg/mL associated with a decrease in V(max) and Hill coefficient. We also showed that it blocks the Cl(-) and K(+) mechanosensitive channels VSORC and TREK-1 at similar concentrations. In contrast, the nonmechanosensitive Cl(-) and K(+) channels CFTR and TASK-1 and the Na(+)-coupled glucose transport, which share functional features with VSORC, TREK-1, and NHE-1, respectively, were insensitive to cisplatin. We next investigated whether cisplatin action was due to a direct effect on membrane or to cortical actin remodeling that would affect mechanosensors. Using scanning electron microscopy, in vivo actin labeling, and atomic force microscopy, we did not observe any modification of the Young's modulus and actin cytoskeleton for up to 60 and 120 μg/mL cisplatin, whereas these concentrations modified membrane morphology. Our results reveal a novel mechanism for cisplatin, which affects mechanosensitive channels and transporters involved in cell fate programs and/or expressed in mechanosensitive organs in which cisplatin elicits strong secondary effects, such as the inner ear or the peripheral nervous system. These results might constitute a common denominator to previously unrelated effects of this drug.

  5. Acute Copper and Ascorbic Acid Supplementation Inhibits Non-heme Iron Absorption in Humans.

    PubMed

    Olivares, Manuel; Figueroa, Constanza; Pizarro, Fernando

    2016-08-01

    The objective of the study is to determine the effect of copper (Cu) plus the reducing agent ascorbic acid (AA) on the absorption of non-heme iron (Fe). Experimental study with block design in which each subject was his own control. After signing an informed consent, 14 adult women using an effective method of contraception and negative pregnancy test received 0.5 mg Fe, as ferrous sulfate, alone or with Cu, as copper sulfate, plus ascorbic acid (AA/Cu 2/1 molar ratio) at 4/1; 6/1 and 8/1 Cu/Fe molar ratios as an aqueous solution on days 1, 2, 14, and 15 of the study. Fe absorption was assessed by erythrocyte incorporation of iron radioisotopes (55)Fe and (59)Fe. Geometric mean (range ± SD) absorption of Fe at 4/1 and 6/1 Cu/Fe molar ratios (and AA/Cu 2/1 molar ratio) and Fe alone was 57.4 % (35.7-92.1 %), 64.2 % (45.8-89.9 %), and 38.8 % (20.4-73.8 %), respectively (ANOVA for repeated measures p < 0.001; post hoc test Scheffé, p < 0.05). This is attributable to the enhancing effect of AA on non-heme Fe absorption; however, Fe absorption at Cu/Fe 8/1 molar ratio was 47.3 % (27.7-80.8) (p = NS compared with Fe alone). It was expected that Fe absorption would have been equal or greater than at 4/1 and 6/1 molar ratios. Copper in the presence of ascorbic acid inhibits non-heme Fe absorption at Cu/Fe 8/1 molar ratio.

  6. Pharmacological inhibition of p38 mitogen-activated protein kinases affects KC/CXCL1-induced intraluminal crawling, transendothelial migration, and chemotaxis of neutrophils in vivo.

    PubMed

    Xu, Najia; Hossain, Mokarram; Liu, Lixin

    2013-01-01

    p38 mitogen-activated protein kinase (MAPK) signalling is critical in the pathophysiology of a variety of inflammatory processes. Leukocyte recruitment to the site of inflammation is a multistep process governed by specific signalling cascades. After adhesion in the lumen, many leukocytes crawl to optimal sites at endothelial junctions and transmigrate to extravascular tissue in a Mac-1-dependent manner. The signalling mechanisms that regulate postadhesion steps of intraluminal crawling, transmigration, and chemotaxis in tissue remain incompletely understood. The present study explored the effect of p38 MAPK inhibitor SB203580 on various parameters of neutrophil recruitment triggered by chemokine KC (CXCL1) gradient. Neutrophil-endothelial interactions in microvasculature of murine cremaster muscle were determined using intravital microscopy and time-lapsed video analysis. SB203580 (100 nM) did not change leukocyte rolling but significantly attenuated neutrophil adhesion, emigration, and transmigration and impaired the initiation of neutrophil crawling and transmigration. In response to KC chemotactic gradient, SB203580 significantly reduced the velocity of migration and chemotaxis index of neutrophils in tissue. The upregulation of Mac-1 expression in neutrophils stimulated by KC was significantly blunted by SB203580 in vitro. Collectively, our findings demonstrate that pharmacological suppression of p38 MAPK significantly impairs multiple steps of neutrophil recruitment in vivo.

  7. The inhibition of the dorsal paragigantocellular reticular nucleus induces waking and the activation of all adrenergic and noradrenergic neurons: a combined pharmacological and functional neuroanatomical study.

    PubMed

    Clément, Olivier; Valencia Garcia, Sara; Libourel, Paul-Antoine; Arthaud, Sébastien; Fort, Patrice; Luppi, Pierre-Hervé

    2014-01-01

    GABAergic neurons specifically active during paradoxical sleep (PS) localized in the dorsal paragigantocellular reticular nucleus (DPGi) are known to be responsible for the cessation of activity of the noradrenergic neurons of the locus coeruleus during PS. In the present study, we therefore sought to determine the role of the DPGi in PS onset and maintenance and in the inhibition of the LC noradrenergic neurons during this state. The effect of the inactivation of DPGi neurons on the sleep-waking cycle was examined in rats by microinjection of muscimol, a GABAA agonist, or clonidine, an alpha-2 adrenergic receptor agonist. Combining immunostaining of the different populations of wake-inducing neurons with that of c-FOS, we then determined whether muscimol inhibition of the DPGi specifically induces the activation of the noradrenergic neurons of the LC. Slow wave sleep and PS were abolished during 3 and 5 h after muscimol injection in the DPGi, respectively. The application of clonidine in the DPGi specifically induced a significant decrease in PS quantities and delayed PS appearance compared to NaCl. We further surprisingly found out that more than 75% of the noradrenergic and adrenergic neurons of all adrenergic and noradrenergic cell groups are activated after muscimol treatment in contrast to the other wake active systems significantly less activated. These results suggest that, in addition to its already know inhibition of LC noradrenergic neurons during PS, the DPGi might inhibit the activity of noradrenergic and adrenergic neurons from all groups during PS, but also to a minor extent during SWS and waking.

  8. Ibrutinib inhibits pre-BCR(+) B-cell acute lymphoblastic leukemia progression by targeting BTK and BLK.

    PubMed

    Kim, Ekaterina; Hurtz, Christian; Koehrer, Stefan; Wang, Zhiqiang; Balasubramanian, Sriram; Chang, Betty Y; Müschen, Markus; Davis, R Eric; Burger, Jan A

    2017-03-02

    Targeting B-cell receptor (BCR) signaling is a successful therapeutic strategy in mature B-cell malignancies. Precursor BCR (pre-BCR) signaling, which is critical during normal B lymphopoiesis, also plays an important role in pre-BCR(+) B cell acute lymphoblastic leukemia (B-ALL). Here, we investigated the activity and mechanism of action of the BTK inhibitor ibrutinib in preclinical models of B-ALL. Pre-BCR(+) ALL cells were exquisitely sensitive to ibrutinib at therapeutically relevant drug concentrations. In pre-BCR(+) ALL, ibrutinib thwarted autonomous and induced pre-BCR signaling, resulting in deactivation of PI3K/Akt signaling. Ibrutinib modulated the expression of pre-BCR regulators (PTPN6, CD22, CD72, and PKCβ) and substantially reduced BCL6 levels. Ibrutinib inhibited ALL cell migration toward CXCL12 and beneath marrow stromal cells and reduced CD44 expression. CRISPR-Cas9 gene editing revealed that both BTK and B lymphocyte kinase (BLK) are relevant targets of ibrutinib in pre-BCR(+) ALL. Consequently, in mouse xenograft models of pre-BCR(+) ALL, ibrutinib treatment significantly prolonged survival. Combination treatment of ibrutinib with dexamethasone or vincristine demonstrated synergistic activity against pre-BCR(+) ALL. These data corroborate ibrutinib as a promising targeted agent for pre-BCR(+) ALL and highlight the importance of ibrutinib effects on alternative kinase targets.

  9. Coxsackievirus B3 Directly Induced Th17 Cell Differentiation by Inhibiting Nup98 Expression in Patients with Acute Viral Myocarditis

    PubMed Central

    Long, Qi; Liao, Yu-Hua; Xie, Yu; Liang, Wei; Cheng, Xiang; Yuan, Jing; Yu, Miao

    2016-01-01

    Th17 cells play a key role in the progression of coxsackievirus B3 (CVB3)-induced acute viral myocarditis (AVMC). However, the direct effect of virus on Th17 cell differentiation is still unknown. Recently, nucleoporin (Nup) 98 has been proved to be associated with lymphocyte differentiation. Therefore, we investigated whether Nup98 mediated Th17 cell differentiation in AVMC. In our study, patients with AVMC and healthy controls were recruited. The results showed that CVB3 could enter into the CD4+ T cells in AVMC patients and healthy controls. After transfecting purified CD4+ T cells with CVB3 in vitro, the Th17 cell frequency, IL-17 secretion, and RORγT synthesis were increased while the Nup98 levels were decreased. Furthermore, down-regulating Nup98 expression by siRNA-Nup98 in CD4+ T cells resulted in the elevated Th17 cell frequency and IL-17 secretion, along with enhanced levels of RORγT, dissociative p300/CBP, and acetylated Stat3. Up-regulation of Nup98 expression by pcDNA3.1-Nup98 showed the opposite effects. Our results suggested that CVB3 directly induced CD4+ T cell differentiation into Th17 cells by inhibiting Nup98 expression, representing a therapeutic target in AVMC. PMID:28018858

  10. PI3K inhibition synergizes with glucocorticoids but antagonizes with methotrexate in T-cell acute lymphoblastic leukemia

    PubMed Central

    Silveira, André Bortolini; Laranjeira, Angelo Brunelli Albertoni; Rodrigues, Gisele Olinto Libanio; Leal, Paulo César; Cardoso, Bruno António; Barata, João Taborda; Yunes, Rosendo Augusto; Zanchin, Nilson Ivo Tonin; Brandalise, Sílvia Regina; Yunes, José Andrés

    2015-01-01

    The PI3K pathway is frequently hyperactivated in primary T-cell acute lymphoblastic leukemia (T-ALL) cells. Activation of the PI3K pathway has been suggested as one mechanism of glucocorticoid resistance in T-ALL, and patients harboring mutations in the PI3K negative regulator PTEN may be at increased risk of induction failure and relapse. By gene expression microarray analysis of T-ALL cells treated with the PI3K inhibitor AS605240, we identified Myc as a prominent downstream target of the PI3K pathway. A significant association was found between the AS605240 gene expression signature and that of glucocorticoid resistance and relapse in T-ALL. AS605240 showed anti-leukemic activity and strong synergism with glucocorticoids both in vitro and in a NOD/SCID xenograft model of T-ALL. In contrast, PI3K inhibition showed antagonism with methotrexate and daunorubicin, drugs that preferentially target dividing cells. This antagonistic interaction, however, could be circumvented by the use of correct drug scheduling schemes. Our data indicate the potential benefits and difficulties for the incorporation of PI3K inhibitors in T-ALL therapy. PMID:25869207

  11. [Subgroup analysis results of platelet inhibition trial in acute coronary syndrome patients (PLATO) who underwent intervention or medical treatment].

    PubMed

    Aksakal, Enbiya

    2013-04-01

    Antiplatelet agents are among the most important drug classes in reducing mortality in patients with acute coronary syndromes (ACS). Ticagrelor is the first reversible and direct acting P2Y(12) receptor inhibitor with an earlier onset of action compared to clopidogrel. The PLATO study (Platelet Inhibition and Patient Outcomes) with ticagrelor was conducted with a design providing consistency with the current clinical practice, including all forms of ACS and a wide spectrum of treatment options in 18624 patients from 862 centers in 43 countries. Of these patients, 13408 underwent interventional procedures (ticagrelor/clopidogrel; 6732/6676) (PLATO-INVASIVE). As reported by the investigator, non-invasive treatment strategy was planned for 5216 patients (ticagrelor/clopidogrel; 2601/2615). However, 2040 patients in this group received interventional treatment during the follow-up (PLATO-NON-INVASIVE/MEDICAL TREATMENT). 1261 patients requiring surgical treatment underwent coronary artery bypass grafting (CABG) within 7 days after the discontinuation of study treatment (ticagrelor/clopidogrel; 632/629) (PLATO-CABG). The results of these three subgroups were consistent with the main PLATO study results, demonstrating that ticagrelor reduced the primary (cardiovascular death, myocardial Infarction and stroke) and secondary composite endpoints without increasing bleeding compared with clopidogrel. Ticagrelor fulfills an important unmet need regarding antiplatelet effectiveness in patients with ACS. This review evaluates the INVASIVE and MEDICAL subgroup studies of the PLATO study.

  12. Acute Inhibition of MEK Suppresses Congenital Melanocytic Nevus Syndrome in a Murine Model Driven by Activated NRAS and Wnt Signaling.

    PubMed

    Pawlikowski, Jeffrey S; Brock, Claire; Chen, Sheau-Chiann; Al-Olabi, Lara; Nixon, Colin; McGregor, Fiona; Paine, Simon; Chanudet, Estelle; Lambie, Wendy; Holmes, William M; Mullin, James M; Richmond, Ann; Wu, Hong; Blyth, Karen; King, Ayala; Kinsler, Veronica A; Adams, Peter D

    2015-08-01

    Congenital melanocytic nevus (CMN) syndrome is the association of pigmented melanocytic nevi with extra-cutaneous features, classically melanotic cells within the central nervous system, most frequently caused by a mutation of NRAS codon 61. This condition is currently untreatable and carries a significant risk of melanoma within the skin, brain, or leptomeninges. We have previously proposed a key role for Wnt signaling in the formation of melanocytic nevi, suggesting that activated Wnt signaling may be synergistic with activated NRAS in the pathogenesis of CMN syndrome. Some familial pre-disposition suggests a germ-line contribution to CMN syndrome, as does variability of neurological phenotypes in individuals with similar cutaneous phenotypes. Accordingly, we performed exome sequencing of germ-line DNA from patients with CMN to reveal rare or undescribed Wnt-signaling alterations. A murine model harboring activated NRAS(Q61K) and Wnt signaling in melanocytes exhibited striking features of CMN syndrome, in particular neurological involvement. In the first model of treatment for this condition, these congenital, and previously assumed permanent, features were profoundly suppressed by acute post-natal treatment with a MEK inhibitor. These data suggest that activated NRAS and aberrant Wnt signaling conspire to drive CMN syndrome. Post-natal MEK inhibition is a potential candidate therapy for patients with this debilitating condition.

  13. Protective effects of ethyl pyruvate on lipopolysaccharide-induced acute lung injury through inhibition of autophagy in neutrophils

    PubMed Central

    Zhu, Qingteng; Wang, Hui; Wang, Hairong; Luo, Yong; Yu, Yang; Du, Qirong; Fei, Aihua; Pan, Shuming

    2017-01-01

    Among a number of clinical factors, bacterial infection is one of the most common causes of acute lung injury (ALI), a serious complication that carries a high risk of mortality (~40%). During the process of ALI, intense local and systemic inflammation is elicited, which exacerbates the injury. Neutrophil infiltration into airspace is observed in early stage of ALI, and is required for the full development of ALI through an array of mechanisms, including the release of granule contents and the production of pro-inflammatory cytokines, due to the overactivation of complement and cytokines. The present study noted that ethyl pyruvate alleviated ALI in lipopolysaccharide (LPS)-induced ALI mice. Increased autophagy in neutrophils from ALI mice was observed, while ethyl pyruvate diminished autophagy in neutrophils and constrained granule release, and therefore myeloperoxidase (MPO) in bronchoalveolar lavage fluid and the production of proinflammatory cytokines. Using neutrophil cells, it was identified that autophagy was required for neutrophil activation and granule release, and that ethyl pyruvate caused neutrophil autophagy, leading to the restriction of granule release, and thus contributing to the mitigation of ALI. If autophagy was obviated through knockdown of key regulator of autophagy Atg5, the effects of ethyl pyruvate on granule release by neutrophils disappeared. Taken together, the results demonstrated that ethyl pyruvate alleviates ALI through inhibition of autophagy-induced granule release by neutrophils, and this mechanism suggested a novel potential therapeutic target in autophagy regulation for ALI. PMID:28098908

  14. Acute hemodynamic effects of angiotensin- converting enzyme inhibition after prolonged cardiac arrest with Bretschneider's solution.

    PubMed

    Hoyer, Alexandro; Kempfert, Jörg; Pritzwald-Stegmann, Patrick; Mohr, Friedrich-Wilhelm; Dhein, Stefan

    2014-12-01

    Evidence as to how ACE inhibitors attenuate ischemia-reperfusion injury (IR) after cardioplegic arrest remains scarce. Twenty-four rabbit hearts were perfused on a Langendorff apparatus. Control hearts (n = 6) were arrested with pure histidine-tryptophan-ketoglutarate (HTK)-Bretschneider. Treatment groups received added to the cardioplegic solution (n = 6) captopril (100 μmol/l) and losartan (100 μmol/l) for selective AT1-receptor antagonism or BQ123 (100 nmol/l) for selective ETA-receptor antagonism. Pre-ischemic equilibration of 45 min was followed by 90 min of cardioplegic arrest and 30 min of reperfusion. Indices of myocardial contractility (LVP, dp/dt max, dp/dt min), coronary flow, heart rate, and O2 consumption were recorded before and after ischemic arrest. Tissue adenosine triphosphate (ATP) and malondialdehyde (MDA) contents were measured to evaluate energy content and oxidative stress, respectively. After selective cardiac arrest with Bretschneider, captopril-treated hearts showed improved hemodynamics compared to control and the other treatment groups. Oxygen consumption was significantly decreased during early reperfusion in captopril-treated hearts (34 ± 3 μmol/min/g/mmHg) compared to controls and losartan- and BQ123-treated hearts (controls: 77 ± 9 μmol/min/g/mmHg, p = 0.003; losartan: 54 ± 9 μmol/min/g/mmHg, p = 0.015; BQ123: 64 ± 13 μmol/min/g/mmHg, p = 0.046). The ATP content of the reperfused tissue was significantly elevated after captopril treatment compared to control group (24 ± 2 vs. 16 ± 2 μmol/g, p = 0.033), whereas the level of MDA was substantially decreased (0.58 ± 0.163 vs. 1.5 ± 0.28 μmol/g, p = 0.009). ACE inhibition leads to a significantly greater and faster recovery of myocardial contractility after prolonged cardiac arrest with Bretschneider solution. Due to decreased oxygen consumption, myocardial protection is enhanced. The association between ACE and ischemia cannot be clarified by selective blockade of

  15. Paradoxical pharmacology: turning our pharmacological models upside down.

    PubMed

    Page, Clive

    2011-04-01

    Paradoxical pharmacology is a term first suggested by Richard Bond to refer to intriguing observations that chronic use of some drug types can have the opposite biological effect(s) to those seen following acute administration of the same drug. A good example of 'paradoxical pharmacology' is the research Richard has pioneered showing that whereas acute administration of β-blockers is contraindicated in the treatment of asthma, chronic use of certain β-blockers can have therapeutic benefit. It would appear that those β-blockers that can act as inverse agonists at the β2 receptor particularly show this paradoxical effect and the findings of Richard's research not only challenge the dogma of the treatment of asthma but also challenge many of the pharmacological principles of ligand/receptor interactions established by Sir James Black and others. In this paper, I discuss Richard's efforts to evaluate the chronic effects of β-blockers in the airways and how this research caught the imagination of Sir James Black.

  16. The pharmacology of TRP channels

    PubMed Central

    Holzer, Peter; Izzo, Angelo A

    2014-01-01

    This themed issue of the British Journal of Pharmacology contains review and research articles on recent advances in transient receptor potential (TRP) channel pharmacology. The review articles, written by a panel of distinguished experts, address the rapid progress in TRP channel research in fields as diverse as oncology, urology, dermatology, migraine, inflammation and pain. These reviews are complemented by original research reports focusing, among others, on the emerging roles of TRPV1 in osteoporosis and cystitis and on evodiamine as a lead structure for the development of potent TRPV1 agonists/desensitizers. Other papers highlight the differences in TRPV3 pharmacology between recombinant and native systems, the mechanisms of TRPM3 activation/inhibition and TRPP2 as a target of naringenin, a dietary flavonoid with anticancer actions. New therapeutic opportunities in pain may arise from the strategy to combine TRP channel and cell membrane impermeant sodium channel blockers to inhibit sensory nerve activity. LINKED ARTICLES This article is part of a themed section on the pharmacology of TRP channels. To view the other articles in this section visit http://dx.doi.org/10.1111/bph.2014.171.issue-10 PMID:24773265

  17. American Society of Clinical Oncology Clinical Practice Guideline Update on the Use of Pharmacologic Interventions Including Tamoxifen, Raloxifene, and Aromatase Inhibition for Breast Cancer Risk Reduction

    PubMed Central

    Visvanathan, Kala; Chlebowski, Rowan T.; Hurley, Patricia; Col, Nananda F.; Ropka, Mary; Collyar, Deborah; Morrow, Monica; Runowicz, Carolyn; Pritchard, Kathleen I.; Hagerty, Karen; Arun, Banu; Garber, Judy; Vogel, Victor G.; Wade, James L.; Brown, Powel; Cuzick, Jack; Kramer, Barnett S.; Lippman, Scott M.

    2009-01-01

    Purpose To update the 2002 American Society of Clinical Oncology guideline on pharmacologic interventions for breast cancer (BC) risk reduction. Methods A literature search identified relevant randomized trials published since 2002. Primary outcome of interest was BC incidence (invasive and noninvasive). Secondary outcomes included BC mortality, adverse events, and net health benefits. An expert panel reviewed the literature and developed updated consensus guidelines. Results Seventeen articles met inclusion criteria. In premenopausal women, tamoxifen for 5 years reduces the risk of BC for at least 10 years, particularly estrogen receptor (ER) –positive invasive tumors. Women ≤ 50 years of age experience fewer serious side effects. Vascular and vasomotor events do not persist post-treatment across all ages. In postmenopausal women, raloxifene and tamoxifen reduce the risk of ER-positive invasive BC with equal efficacy. Raloxifene is associated with a lower risk of thromboembolic disease, benign uterine conditions, and cataracts than tamoxifen in postmenopausal women. No evidence exists establishing whether a reduction in BC risk from either agent translates into reduced BC mortality. Recommendations In women at increased risk for BC, tamoxifen (20 mg/d for 5 years) may be offered to reduce the risk of invasive ER-positive BC, with benefits for at least 10 years. In postmenopausal women, raloxifene (60 mg/d for 5 years) may also be considered. Use of aromatase inhibitors, fenretinide, or other selective estrogen receptor modulators to lower BC risk is not recommended outside of a clinical trial. Discussion of risks and benefits of preventive agents by health providers is critical to patient decision making. PMID:19470930

  18. Genetic and pharmacological evidence that 5-HT2C receptor activation, but not inhibition, affects motivation to feed under a progressive ratio schedule of reinforcement.

    PubMed

    Fletcher, Paul J; Sinyard, Judy; Higgins, Guy A

    2010-11-01

    Previous work showed that 5-HT(2C) receptor agonists reduce cocaine self-administration on a progressive ratio (PR) schedule of reinforcement, whereas a 5-HT(2C) receptor antagonist enhances responding for cocaine. The present experiments examined the effects of Ro60-0175 (5-HT(2C) agonist) and SB242084 (5-HT(2C) receptor antagonist) in rats on responding for food on a PR schedule; responding was also determined in mice lacking functional 5-HT(2C) receptors. In food-restricted rats, lever pressing reinforced by regular food pellets or sucrose pellets was reduced by Ro60-0175. This effect was blocked by SB242084, and was absent in mice lacking functional 5-HT(2C) receptors. A number of studies examined the effects of SB242084 on responding for food under a variety of conditions. These included manipulation of food type (regular pellets versus sucrose pellets), nutritional status of the animals (food restriction versus no restriction), and rate of progression of the increase in ratio requirements on the PR schedule. In all cases there was no evidence of enhanced responding for food by SB242084. Mice lacking functional 5-HT(2C) receptors did not differ from wildtype mice in responding for food in either food-restricted or non-restricted states. The effects of Ro60-0175 are consistent with its effects on food consumption and motivation to self-administer cocaine. Unlike their effects on cocaine self-administration, pharmacological blockade of 5-HT(2C) receptors, and genetic disruption of 5-HT(2C) receptor function do not alter the motivation to respond for food. Because the 5-HT(2C) receptor exerts a modulatory effect on dopamine function, the differential effects of reduced 5-HT(2C) receptor mediated transmission on responding for food versus cocaine may relate to a differential role of this neurotransmitter in mediating these two behaviours.

  19. Pharmacological profile of the clonidine-induced inhibition of vasodepressor sensory outflow in pithed rats: correlation with α2A/2C-adrenoceptors

    PubMed Central

    Villalón, C M; Albarrán-Juárez, J A; Lozano-Cuenca, J; Pertz, H H; Görnemann, T; Centurión, D

    2008-01-01

    Background and purpose: Resistance blood vessels are innervated by sympathetic and primary sensory nerves, which modulate vascular tone through the release of noradrenaline and calcitonin gene-related peptide (CGRP), respectively. Moreover, electrical stimulation of the perivascular sensory outflow in pithed rats results in vasodepressor responses which are mainly mediated by CGRP release. The present study has investigated the role of α2-adrenoceptors in the inhibition of these vasodepressor responses. Experimental approach: 144 pithed male Wistar rats were pretreated with hexamethonium (2 mg kg−1 min−1) followed by i.v. continuous infusions of either methoxamine (15 and 30 μg kg−1 min−1) or clonidine (3, 10 and 30 μg kg−1 min−1). Under these conditions, electrical stimulation (0.56–5.6 Hz; 50 V and 2 ms) of the spinal cord (T9–T12) resulted in frequency-dependent decreases in diastolic blood pressure. Key results: The infusion of clonidine (10 μg kg−1 min−1), as compared to those of methoxamine (15 or 30 μg kg−1 min−1), inhibited the vasodepressor responses to electrical stimulation without affecting those to i.v. bolus injections of α-CGRP (0.1–1 μg kg−1). This inhibition by clonidine was: (i) antagonized by 300 μg kg−1 rauwolscine (α2A/2B/2C), 300 and 1000 μg kg−1 BRL44408 (α2A), or 10 and 30 μg kg−1 MK912 (α2C); and (ii) unaffected by 1 ml kg−1 saline, 100 μg kg−1 BRL44408, 3000 and 10000 μg kg−1 imiloxan (α2B) or 3 μg kg−1 MK912. Conclusions and implications: The inhibition produced by 10 μg kg−1 min−1 clonidine on the vasodepressor (perivascular) sensory outflow in rats may be mainly mediated by prejunctional α2A/α2C-adrenoceptors. PMID:18297098

  20. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis.

    PubMed

    Li, Jingjing; Chen, Kan; Li, Sainan; Liu, Tong; Wang, Fan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA)-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis.

  1. Pharmacologic IKK/NF-κB inhibition causes antigen presenting cells to undergo TNFα dependent ROS-mediated programmed cell death

    NASA Astrophysics Data System (ADS)

    Tilstra, Jeremy S.; Gaddy, Daniel F.; Zhao, Jing; Davé, Shaival H.; Niedernhofer, Laura J.; Plevy, Scott E.; Robbins, Paul D.

    2014-01-01

    Monocyte-derived antigen presenting cells (APC) are central mediators of the innate and adaptive immune response in inflammatory diseases. As such, APC are appropriate targets for therapeutic intervention to ameliorate certain diseases. APC differentiation, activation and functions are regulated by the NF-κB family of transcription factors. Herein, we examined the effect of NF-κB inhibition, via suppression of the IκB Kinase (IKK) complex, on APC function. Murine bone marrow-derived macrophages and dendritic cells (DC), as well as macrophage and DC lines, underwent rapid programmed cell death (PCD) after treatment with several IKK/NF-κB inhibitors through a TNFα-dependent mechanism. PCD was induced proximally by reactive oxygen species (ROS) formation, which causes a loss of mitochondrial membrane potential and activation of a caspase signaling cascade. NF-κB-inhibition-induced PCD of APC may be a key mechanism through which therapeutic targeting of NF-κB reduces inflammatory pathologies.

  2. Suppression of Invasion and Metastasis of Triple-Negative Breast Cancer Lines by Pharmacological or Genetic Inhibition of Slug Activity123

    PubMed Central

    Ferrari-Amorotti, Giovanna; Chiodoni, Claudia; Shen, Fei; Cattelani, Sara; Soliera, Angela Rachele; Manzotti, Gloria; Grisendi, Giulia; Dominici, Massimo; Rivasi, Francesco; Colombo, Mario Paolo; Fatatis, Alessandro; Calabretta, Bruno

    2014-01-01

    Most triple-negative breast cancers (TNBCs) exhibit gene expression patterns associated with epithelial-to-mesenchymal transition (EMT), a feature that correlates with a propensity for metastatic spread. Overexpression of the EMT regulator Slug is detected in basal and mesenchymal-type TNBCs and is associated with reduced E-cadherin expression and aggressive disease. The effects of Slug depend, in part, on the interaction of its N-terminal SNAG repressor domain with the chromatin-modifying protein lysine demethylase 1 (LSD1); thus, we investigated whether tranylcypromine [also known as trans-2-phenylcyclopropylamine hydrochloride (PCPA) or Parnate], an inhibitor of LSD1 that blocks its interaction with Slug, suppresses the migration, invasion, and metastatic spread of TNBC cell lines. We show here that PCPA treatment induces the expression of E-cadherin and other epithelial markers and markedly suppresses migration and invasion of TNBC cell lines MDA-MB-231 and BT-549. These effects were phenocopied by Slug or LSD1 silencing. In two models of orthotopic breast cancer, PCPA treatment reduced local tumor growth and the number of lung metastases. In mice injected directly in the blood circulation with MDA-MB-231 cells, PCPA treatment or Slug silencing markedly inhibited bone metastases but had no effect on lung infiltration. Thus, blocking Slug activity may suppress the metastatic spread of TNBC and, perhaps, specifically inhibit homing/colonization to the bone. PMID:25499218

  3. AChE Inhibition-based Multi-target-directed Ligands, a Novel Pharmacological Approach for the Symptomatic and Disease-modifying Therapy of Alzheimer's Disease

    PubMed Central

    Wang, Yu; Wang, Hao; Chen, Hong-zhuan

    2016-01-01

    Alzheimer's disease (AD) is the most common form of dementia in elder people, characterised by a progressive decline in memory as a result of an impairment of cholinergic neurotransmission. To date acetylcholinesterase inhibitors (AChEIs) have become the most prescribed drugs for the symptomatic treatment of mild to moderate AD. However, the traditional “one molecule-one target” paradigm is not sufficient and appropriate to yield the desired therapeutic efficacy since multiple factors, such as amyloid-β (Aβ) deposits, neuroinflammation, oxidative stress, and decreased levels of acetylcholine (ACh) have been thought to play significant roles in the AD pathogenesis. New generation of multi-target drugs is earnestly demanded not only for ameliorating symptoms but also for modifying the disease. Herein, we delineated the catalytic and non-catalytic functions of AChE, and summarized the works of our group and others in research and development of novel AChEI-based multi-target-directed ligands (MTDLs), such as dual binding site AChEIs and multi-target AChEIs inhibiting Aβ aggregation, regulating Aβ procession, antagonizing platelet-activating factor (PAF) receptor, scavenging oxygen radical, chelating metal ions, inhibiting monoamine oxidase B (MAO-B), blocking N-methyl-D-aspartic acid (NMDA) receptor and others. PMID:26786145

  4. Lipid transfer to HDL is higher in marathon runners than in sedentary subjects, but is acutely inhibited during the run.

    PubMed

    Vaisberg, Mauro; Bachi, André L L; Latrilha, Conceição; Dioguardi, Giuseppe S; Bydlowski, Sergio P; Maranhão, Raul C

    2012-07-01

    Although exercise increases HDL-cholesterol, exercise-induced changes in HDL metabolism have been little explored. Lipid transfer to HDL is essential for HDL's role in reverse cholesterol transport. We investigated the effects of acute exhaustive exercise on lipid transfer to HDL. We compared plasma lipid, apolipoprotein and cytokine levels and in vitro transfer of four lipids from a radioactively labeled lipid donor nanoemulsion to HDL in sedentary individuals (n = 28) and in marathon runners (n = 14) at baseline, immediately after and 72 h after a marathon. While HDL-cholesterol concentrations and apo A1 levels were higher in marathon runners, LDL-cholesterol, apo B and triacylglycerol levels were similar in both groups. Transfers of non-esterified cholesterol [6.8 (5.7-7.2) vs. 5.2 (4.5-6), p = 0.001], phospholipids [21.7 (20.4-22.2) vs. 8.2 (7.7-8.9), p = 0.0001] and triacylglycerol [3.7 (3.1-4) vs. 1.3 (0.8-1.7), p = 0.0001] were higher in marathon runners, but esterified-cholesterol transfer was similar. Immediately after the marathon, LDL- and HDL-cholesterol concentrations and apo A1 levels were unchanged, but apo B and triacylglycerol levels increased. Lipid transfer of non-esterified cholesterol [6.8 (5.7-7.2) vs. 5.8 (4.9-6.6), p = 0.0001], phospholipids [21.7 (20.4-22.2) vs. 19.1 (18.6-19.3), p = 0.0001], esterified-cholesterol [3.2 (2.2-3.8) vs. 2.3 (2-2.9), p = 0.02] and triacylglycerol [3.7 (3.1-4) vs. 2.6 (2.1-2.8), p = 0.0001] to HDL were all reduced immediately after the marathon but returned to baseline 72 h later. Running a marathon increased IL-6 and TNF-α levels, but after 72 h these values returned to baseline. Lipid transfer, except esterified-cholesterol transfer, was higher in marathon runners than in sedentary individuals, but the marathon itself acutely inhibited lipid transfer. In light of these novel observations, further study is required to clarify how these metabolic changes can influence HDL composition and

  5. Inhibition of secretory phospholipase A2 activity attenuates acute cardiogenic pulmonary edema induced by isoproterenol infusion in mice after myocardial infarction.

    PubMed

    Kawabata, Kenichi; Fujioka, Daisuke; Kobayashi, Tsuyoshi; Saito, Yukio; Obata, Jun-Ei; Nakamura, Takamitsu; Yano, Toshiaki; Watanabe, Kazuhiro; Watanabe, Yosuke; Mishina, Hideto; Kugiyama, Kiyotaka

    2010-10-01

    Several types of secretory phospholipase A2 (sPLA2) are expressed in lung tissue, yielding various eicosanoids that might cause pulmonary edema. This study examined whether inhibition of sPLA2 activity attenuates acute cardiogenic pulmonary edema in mice. Acute cardiogenic pulmonary edema was induced in C57BL/6J male mice by an increase in heart rate with continuous intravenous infusion of isoproterenol (ISP) (10 mg/kg/h) at 2 weeks after the creation of myocardial infarction by left coronary artery ligation. Just before ISP infusion, a single intraperitoneal injection of 100 mg/kg LY374388, a prodrug of LY329722 that inhibits sPLA2 activity, or vehicle was administered. The ISP infusion after myocardial infarction induced interstitial and alveolar edema on lung histology. Furthermore, it increased the lung-to-body weight ratio, pulmonary vascular permeability evaluated by the Evans blue extravasation method, lung activity of sPLA2, and lung content of thromboxane A2 and leukotriene B4. These changes were significantly attenuated by LY374388 treatment. In Kaplan-Meier analysis, the survival rate during the ISP infusion after myocardial infarction was significantly higher in LY374388- than in vehicle-treated mice. Similar results were obtained with another inhibitor of sPLA2 activity, para-bromophenacyl bromide. In conclusion, inhibition of sPLA2 activity suppressed acute cardiogenic pulmonary edema.

  6. Does cortisol influence core executive functions? A meta-analysis of acute cortisol administration effects on working memory, inhibition, and set-shifting.

    PubMed

    Shields, Grant S; Bonner, Joseph C; Moons, Wesley G

    2015-08-01

    The hormone cortisol is often believed to play a pivotal role in the effects of stress on human cognition. This meta-analysis is an attempt to determine the effects of acute cortisol administration on core executive functions. Drawing on both rodent and stress literatures, we hypothesized that acute cortisol administration would impair working memory and set-shifting but enhance inhibition. Additionally, because cortisol is thought to exert different nongenomic (rapid) and genomic (slow) effects, we further hypothesized that the effects of cortisol would differ as a function of the delay between cortisol administration and cognitive testing. Although the overall analyses were nonsignificant, after separating the rapid, nongenomic effects of cortisol from the slower, genomic effects of cortisol, the rapid effects of cortisol enhanced response inhibition, g+ = 0.113, p=.016, but impaired working memory, g+ = -0.315, p=.008, although these effects reversed over time. Contrary to our hypotheses, there was no effect of cortisol administration on set-shifting. Thus, although we did not find support for the idea that increases in cortisol influence set-shifting, we found that acute increases in cortisol exert differential effects on working memory and inhibition over time.

  7. Modulation of mGlu2 Receptors, but Not PDE10A Inhibition Normalizes Pharmacologically-Induced Deviance in Auditory Evoked Potentials and Oscillations in Conscious Rats

    PubMed Central

    Ahnaou, Abdallah; Biermans, Ria; Drinkenburg, Wilhelmus H.

    2016-01-01

    Improvement of cognitive impairments represents a high medical need in the development of new antipsychotics. Aberrant EEG gamma oscillations and reductions in the P1/N1 complex peak amplitude of the auditory evoked potential (AEP) are neurophysiological biomarkers for schizophrenia that indicate disruption in sensory information processing. Inhibition of phosphodiesterase (i.e. PDE10A) and activation of metabotropic glutamate receptor (mGluR2) signaling are believed to provide antipsychotic efficacy in schizophrenia, but it is unclear whether this occurs with cognition-enhancing potential. The present study used the auditory paired click paradigm in passive awake Sprague Dawley rats to 1) model disruption of AEP waveforms and oscillations as observed in schizophrenia by peripheral administration of amphetamine and the N-methyl-D-aspartate (NMDA) antagonist phencyclidine (PCP); 2) confirm the potential of the antipsychotics risperidone and olanzapine to attenuate these disruptions; 3) evaluate the potential of mGluR2 agonist LY404039 and PDE10 inhibitor PQ-10 to improve AEP deficits in both the amphetamine and PCP models. PCP and amphetamine disrupted auditory information processing to the first click, associated with suppression of the P1/N1 complex peak amplitude, and increased cortical gamma oscillations. Risperidone and olanzapine normalized PCP and amphetamine-induced abnormalities in AEP waveforms and aberrant gamma/alpha oscillations, respectively. LY404039 increased P1/N1 complex peak amplitudes and potently attenuated the disruptive effects of both PCP and amphetamine on AEPs amplitudes and oscillations. However, PQ-10 failed to show such effect in either models. These outcomes indicate that modulation of the mGluR2 results in effective restoration of abnormalities in AEP components in two widely used animal models of psychosis, whereas PDE10A inhibition does not. PMID:26808689

  8. Pharmacological study of the mechanisms involved in the vasodilator effect produced by the acute application of triiodothyronine to rat aortic rings

    PubMed Central

    Lozano-Cuenca, J.; López-Canales, O.A.; Aguilar-Carrasco, J.C.; Villagrana-Zesati, J.R.; López-Mayorga, R.M.; Castillo-Henkel, E.F.; López-Canales, J.S.

    2016-01-01

    A relationship between thyroid hormones and the cardiovascular system has been well established in the literature. The present in vitro study aimed to investigate the mechanisms involved in the vasodilator effect produced by the acute application of 10-8–10-4 M triiodothyronine (T3) to isolated rat aortic rings. Thoracic aortic rings from 80 adult male Wistar rats were isolated and mounted in tissue chambers filled with Krebs-Henseleit bicarbonate buffer in order to analyze the influence of endothelial tissue, inhibitors and blockers on the vascular effect produced by T3. T3 induced a vasorelaxant response in phenylephrine-precontracted rat aortic rings at higher concentrations (10-4.5–10-4.0 M). This outcome was unaffected by 3.1×10-7 M glibenclamide, 10-3 M 4-aminopyridine (4-AP), 10-5 M indomethacin, or 10-5 M cycloheximide. Contrarily, vasorelaxant responses to T3 were significantly (P<0.05) attenuated by endothelium removal or the application of 10-6 M atropine, 10-5 M L-NG-nitroarginine methyl ester (L-NAME), 10-7 M 1H-(1,2,4)oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), 10-6 M (9S,10R,12R)-2,3,9,10,11,12-Hexahydro-10-methoxy-2,9-dimethyl-1-oxo-9,12-epoxy-1H-diindolo[1,2,3-fg:3′,2′,1′-kl]pyrrolo[3,4-i](1,6)benzodiazocine-10-carboxylic acid, methyl ester KT 5823, 10-2 M tetraethylammonium (TEA), or 10-7 M apamin plus 10-7 M charybdotoxin. The results suggest the involvement of endothelial mechanisms in the vasodilator effect produced by the acute in vitro application of T3 to rat aortic rings. Possible mechanisms include the stimulation of muscarinic receptors, activation of the NO-cGMP-PKG pathway, and opening of Ca2+-activated K+ channels. PMID:27464023

  9. Piperlongumine inhibits the proliferation and survival of B-cell acute lymphoblastic leukemia cell lines irrespective of glucocorticoid resistance

    SciTech Connect

    Han, Seong-Su; Han, Sangwoo; Kamberos, Natalie L.

    2014-09-26

    Highlights: • PL inhibits the proliferation of B-ALL cell lines irrespective of GC-resistance. • PL selectively kills B-ALL cells by increasing ROS, but not normal counterpart. • PL does not sensitize majority of B-ALL cells to DEX. • PL represses the network of constitutively activated TFs and modulates their target genes. • PL may serve as a new therapeutic molecule for GC-resistant B-ALL. - Abstract: Piperlongumine (PL), a pepper plant alkaloid from Piper longum, has anti-inflammatory and anti-cancer properties. PL selectively kills both solid and hematologic cancer cells, but not normal counterparts. Here we evaluated the effect of PL on the proliferation and survival of B-cell acute lymphoblastic leukemia (B-ALL), including glucocorticoid (GC)-resistant B-ALL. Regardless of GC-resistance, PL inhibited the proliferation of all B-ALL cell lines, but not normal B cells, in a dose- and time-dependent manner and induced apoptosis via elevation of ROS. Interestingly, PL did not sensitize most of B-ALL cell lines to dexamethasone (DEX). Only UoC-B1 exhibited a weak synergistic effect between PL and DEX. All B-ALL cell lines tested exhibited constitutive activation of multiple transcription factors (TFs), including AP-1, MYC, NF-κB, SP1, STAT1, STAT3, STAT6 and YY1. Treatment of the B-ALL cells with PL significantly downregulated these TFs and modulated their target genes. While activation of AURKB, BIRC5, E2F1, and MYB mRNA levels were significantly downregulated by PL, but SOX4 and XBP levels were increased by PL. Intriguingly, PL also increased the expression of p21 in B-ALL cells through a p53-independent mechanism. Given that these TFs and their target genes play critical roles in a variety of hematological malignancies, our findings provide a strong preclinical rationale for considering PL as a new therapeutic agent for the treatment of B-cell malignancies, including B-ALL and GC-resistant B-ALL.

  10. Pharmacological profile of the 5-HT-induced inhibition of cardioaccelerator sympathetic outflow in pithed rats: correlation with 5-HT1 and putative 5-ht5A/5B receptors

    PubMed Central

    Sánchez-López, Araceli; Centurión, David; Vázquez, Erika; Arulmani, Udayasankar; Saxena, Pramod R; Villalón, Carlos M

    2003-01-01

    Continuous infusions of 5-hydroxytryptamine (5-HT) inhibit the tachycardiac responses to preganglionic (C7-T1) sympathetic stimulation in pithed rats pretreated with desipramine. The present study identified the pharmacological profile of this inhibitory action of 5-HT. The inhibition induced by intravenous (i.v.) continuous infusions of 5-HT (5.6 μg kg−1 min−1) on sympathetically induced tachycardiac responses remained unaltered after i.v. treatment with saline or the antagonists GR 127935 (5-HT1B/1D), the combination of WAY 100635 (5-HT1A) plus GR 127935, ritanserin (5-HT2), tropisetron (5-HT3/4), LY215840 (5-HT7) or a cocktail of antagonists/inhibitors consisting of yohimbine (α2), prazosin (α1), ritanserin, GR 127935, WAY 100635 and indomethacin (cyclooxygenase), but was abolished by methiothepin (5-HT1/2/6/7 and recombinant 5-ht5A/5B). These drugs, used in doses high enough to block their respective receptors/mechanisms, did not modify the sympathetically induced tachycardiac responses per se. I.v. continuous infusions of the agonists 5-carboxamidotryptamine (5-CT; 5-HT1/7 and recombinant 5-ht5A/5B), CP 93,129 (r5-HT1B), sumatriptan (5-HT1B/1D), PNU-142633 (5-HT1D) and ergotamine (5-HT1B/1D and recombinant 5-ht5A/5B) mimicked the above sympatho-inhibition to 5-HT. In contrast, the agonists indorenate (5-HT1A) and LY344864 (5-ht1F) were inactive. Interestingly, 5-CT-induced cardiac sympatho-inhibition was abolished by methiothepin, the cocktail of antagonists/inhibitors, GR 127935 or the combination of SB224289 (5-HT1B) plus BRL15572 (5-HT1D), but remained unchanged when SB224289 or BRL15572 were given separately. Therefore, 5-HT-induced cardiac sympatho-inhibition, being unrelated to 5-HT2, 5-HT3, 5-HT4, 5-ht6, 5-HT7 receptors, α1/2-adrenoceptor or prostaglandin synthesis, seems to be primarily mediated by (i) 5-HT1 (probably 5-HT1B/1D) receptors and (ii) a novel mechanism antagonized by methiothepin that, most likely, involves putative 5-ht5A/5B

  11. Maternal prolactin inhibition during lactation affects physical performance evaluated by acute exhaustive swimming exercise in adult rat offspring.

    PubMed

    Casimiro-Lopes, G; Lisboa, P C; Koury, J C; Boaventura, G; Passos, M C F; Moura, E G

    2012-02-01

    Maternal prolactin inhibition at the end of lactation programs for metabolic syndrome and hypothyroidism in adult offspring, which could negatively affect exercise performance. We evaluated the effects of maternal hypoprolactinemia in late lactation on physical performance in adult progeny. Lactating Wistar rats were treated with bromocriptine (BRO, 1 mg per day) or saline on days 19, 20, and 21 of lactation and offspring were followed until 180 days old. Physical performance was recorded in untrained rats at 90 and 180 days by an acute exhaustive swimming test (exercise group-Ex). At day 90, BRO offspring showed higher visceral fat mass, higher plasma thiobarbituric acid reactive substances, lower total antioxidant capacity, higher liver glycogen, lower glycemia, and normal insulinemia. Although thyroid hormones (TH) levels were unchanged, mitochondrial glycerol phosphate dehydrogenase (mGPD) activity was lower in muscle and in brown adipose tissue (BAT). At this age, BRO-Ex offspring showed higher exercise capacity, lower blood lactate, higher serum T3, and higher muscle and BAT mGPD activities. At day 180, BRO offspring showed central obesity, hypothyroidism, insulin resistance, and lower EDL (extensor digitorum longus) muscle glycogen with unaltered plasma oxidative stress markers. This group showed no alteration of exercise capacity or blood lactate. After exercise, EDL and liver glycogen were lower, while T3 levels, BAT and muscle mGPD activities were normalized. Liver glycogen seem to be related with higher exercise capacity in younger BRO offspring, while the loss of this temporary advantage maybe related to the hypothyroidism and insulin resistance developed with age.

  12. Inhibition of leukotriene B4 synthesis does not prevent development of acute renal failure following storage and transplantation.

    PubMed

    Lane, N J; Thorniley, M S; Manek, S; Fuller, B J; Green, C J

    1994-12-27

    Compound BW B70C, a selective 5-lipoxygenase inhibitor was tested for its ability to reduce inflammatory damage in an in vivo rabbit model of renal storage and transplantation. Kidneys were stored at 0-2 degrees C for 48 hr prior to autografting. In controls, renal vein LTB4 levels rose significantly after 30 min reperfusion but fell after 2 hr to baseline. TxB2 levels remained at baseline for the 6 hr measured. 6-k-PGF1 alpha levels rose significantly after 1 hr of reperfusion and remained elevated thereafter. Histology after 6 hr reperfusion showed moderate-to-severe cortical edema and mild congestion. Infused colloidal carbon was retained in the perivascular area in a narrow band at the corticomedullary junction, indicating a zone of vascular permeability. At 3 days after transplant, kidneys exhibited widespread tubular necrosis and calcification but little inflammation. Serum creatinine and urea peaked between days 3 and 5. 3/6 rabbits showed no symptoms of renal failure after 3 weeks. Pretreatment with BW B70C prevented the increase in LTB4 but had little effect on TxB2 and 6-k-PGF1 alpha levels. Histology showed no amelioration of cortical edema at 6 hr and congestion and hemorrhage were exacerbated. BW B70C had no effect on either colloidal carbon retention or distribution but did significantly reduce tubular necrosis and calcification at day 3. There was very little inflammatory infiltrate. BW B70C treatment did not improve the long-term viability of transplanted kidneys: 2/6 rabbits showed no symptoms of renal failure after 3 weeks. These data indicate that inhibition of LTB4 synthesis by BW B70C does not prevent the development of acute renal failure following 48 hr hypothermic storage and transplantation.

  13. Acanthopanax versus 3-Methyladenine Ameliorates Sodium Taurocholate-Induced Severe Acute Pancreatitis by Inhibiting the Autophagic Pathway in Rats

    PubMed Central

    Zhou, Guoxiong; Liu, Chun; Wei, Ronglong; Zhu, Shunxing; Xu, Yuefen; Wu, Mengjie; Miao, Qing

    2016-01-01

    Objectives. To observe the therapeutic effects of Acanthopanax and 3-methyladenine against severe acute pancreatitis (SAP). Methods. Sodium taurocholate-induced SAP rats were equally randomized into a SAP group, an Acanthopanax group, and a 3-methyladenine group. Serum amylase levels were determined by ELISA; protein and mRNA expression levels of nucleus nuclear factor kappa B (NF-κB) p65, light chain 3II (LC3-II), and Beclin-1 and mRNA expression levels of Class III phosphatidylinositol 3-kinase (PI3K-III) in pancreas tissue were detected by Western blot and quantitative real-time PCR, respectively; mortality and pathological change of the pancreas were observed at 3, 12, and 24 h after operation. Results. There was no significant difference in mortality between SAP group and both treatment groups (P > 0.05). Serum amylase levels, protein, and mRNA expression levels of nucleus NF-κB p65, LC3-II, and Beclin-1 protein, mRNA expression levels of PI3K-III, and pathological score of the pancreas in both treatment groups were significantly lower than those in SAP group at 12 and 24 h after operation (P < 0.05 or 0.01). The number of autophagosomes and autophagolysosomes of pancreatic acinar cells in both treatment groups was smaller than that in SAP group at 12 and 24 h. Conclusions. Acanthopanax and 3-methyladenine had similar therapeutic effects against SAP in rats. The mechanism may be through inhibiting abnormal autophagy activation of pancreatic acinar cells. PMID:28115794

  14. [Hydrogen sulfide reduces lipopolysaccharide-induced acute lung injury and inhibits expression of phosphorylated p38 MAPK in rats].

    PubMed

    Fan, Ya-Min; Huang, Xin-Li; Dong, Ze-Fei; Ling, Yi-Ling

    2012-12-25

    To investigate the influence of hydrogen sulfide (H₂S) on p38 MAPK signaling pathway during acute lung injury (ALI) caused by lipopolysaccharide (LPS), the rats were randomly divided into six groups: control group, LPS group, LPS + NaHS group, LPS + PPG (cystathionine-γ-lyase inhibitor) group, NaHS group and PPG group. The rats were sacrificed 6 h after injection and lung tissues were obtained. The structure of lung tissues and the number of polymorphonuclear leucocyte (PMN) was observed under optical microscope; the lung myeloperoxidase (MPO) activity, superoxide dismutase (SOD) activity and malondialdehyde (MDA) content were tested; intercellular adhesion molecule-1 (ICAM-1) protein expression changes were detected by immunohistochemical staining; phosphorylated p38 MAPK (p-p38 MAPK) protein expression was detected by Western blotting. The results showed that the lung injury in LPS group was observed, at the same time the MPO activity, the content of MDA, ICAM-1 and p-p38 MAPK protein expressions, the number of PMN were all higher than those in control group (all P < 0.05). Pre-injection of NaHS alleviated the changes induced by LPS, while pre-injection of PPG aggravated those alterations (all P < 0.05). ICAM-1 and p-p38 MAPK protein expressions in lung tissue were positively correlated (r = 0.923, P < 0.01). The results suggest that H2S may reduce LPS-induced ALI through inhibiting the conjugation of p38 MAPK and reducing the expression of ICAM-1.

  15. Screening of a composite library of clinically used drugs and well-characterized pharmacological compounds for cystathionine β-synthase inhibition identifies benserazide as a drug potentially suitable for repurposing for the experimental therapy of colon cancer.

    PubMed

    Druzhyna, Nadiya; Szczesny, Bartosz; Olah, Gabor; Módis, Katalin; Asimakopoulou, Antonia; Pavlidou, Athanasia; Szoleczky, Petra; Gerö, Domokos; Yanagi, Kazunori; Törö, Gabor; López-García, Isabel; Myrianthopoulos, Vassilios; Mikros, Emmanuel; Zatarain, John R; Chao, Celia; Papapetropoulos, Andreas; Hellmich, Mark R; Szabo, Csaba

    2016-11-01

    Cystathionine-β-synthase (CBS) has been recently identified as a drug target for several forms of cancer. Currently no potent and selective CBS inhibitors are available. Using a composite collection of 8871 clinically used drugs and well-annotated pharmacological compounds (including the LOPAC library, the FDA Approved Drug Library, the NIH Clinical Collection, the New Prestwick Chemical Library, the US Drug Collection, the International Drug Collection, the 'Killer Plates' collection and a small custom collection of PLP-dependent enzyme inhibitors), we conducted an in vitro screen in order to identify inhibitors for CBS using a primary 7-azido-4-methylcoumarin (AzMc) screen to detect CBS-derived hydrogen sulfide (H2S) production. Initial hits were subjected to counterscreens using the methylene blue assay (a secondary assay to measure H2S production) and were assessed for their ability to quench the H2S signal produced by the H2S donor compound GYY4137. Four compounds, hexachlorophene, tannic acid, aurintricarboxylic acid and benserazide showed concentration-dependent CBS inhibitory actions without scavenging H2S released from GYY4137, identifying them as direct CBS inhibitors. Hexachlorophene (IC50: ∼60μM), tannic acid (IC50: ∼40μM) and benserazide (IC50: ∼30μM) were less potent CBS inhibitors than the two reference compounds AOAA (IC50: ∼3μM) and NSC67078 (IC50: ∼1μM), while aurintricarboxylic acid (IC50: ∼3μM) was equipotent with AOAA. The second reference compound NSC67078 not only inhibited the CBS-induced AzMC fluorescence signal (IC50: ∼1μM), but also inhibited with the GYY4137-induced AzMC fluorescence signal with (IC50 of ∼6μM) indicative of scavenging/non-specific effects. Hexachlorophene (IC50: ∼6μM), tannic acid (IC50: ∼20μM), benserazide (IC50: ∼20μM), and NSC67078 (IC50: ∼0.3μM) inhibited HCT116 colon cancer cells proliferation with greater potency than AOAA (IC50: ∼300μM). In contrast, although a CBS inhibitor

  16. Pharmacologic Effects of Cannabidiol on Acute Reperfused Myocardial Infarction in Rabbits: Evaluated With 3.0T Cardiac Magnetic Resonance Imaging and Histopathology.

    PubMed

    Feng, Yuanbo; Chen, Feng; Yin, Ting; Xia, Qian; Liu, Yewei; Huang, Gang; Zhang, Jian; Oyen, Raymond; Ni, Yicheng

    2015-10-01

    Cannabidiol (CBD) has anti-inflammatory effects. We explored its therapeutic effects on cardiac ischemia-reperfusion injury with an experimental imaging platform. Reperfused acute myocardial infarction (AMI) was induced in rabbits with a 90-minute coronary artery occlusion followed by 24-hour reperfusion. Before reperfusion, rabbits received 2 intravenous doses of 100 μg/kg CBD (n = 10) or vehicle (control, n = 10). Evans blue was intravenously injected for later detection of the AMI core. Cardiac magnetic resonance imaging was performed to evaluate cardiac morphology and function. After euthanasia, blood troponin I (cTnI) was assessed, and the heart was excised and infused with multifunctional red iodized oil dye. The heart was sliced for digital radiography to quantify the perfusion density rate, area at risk (AAR), and myocardial salvage index, followed by histomorphologic staining. Compared with controls, CBD treatment improved systolic wall thickening (P < 0.05), significantly increased blood flow in the AAR (P < 0.05), significantly decreased microvascular obstruction (P < 0.05), increased the perfusion density rate by 1.7-fold, lowered the AMI core/AAR ratio (P < 0.05), and increased the myocardial salvage index (P < 0.05). These improvements were associated with reductions in serum cTnI, cardiac leukocyte infiltration, and myocellular apoptosis (P < 0.05). Thus, CBD therapy reduced AMI size and facilitated restoration of left ventricular function. We demonstrated that this experimental platform has potential theragnostic utility.

  17. Pharmacological blockade of fatty acid synthase (FASN) reverses acquired autoresistance to trastuzumab (Herceptin by transcriptionally inhibiting 'HER2 super-expression' occurring in high-dose trastuzumab-conditioned SKBR3/Tzb100 breast cancer cells.

    PubMed

    Vazquez-Martin, Alejandro; Colomer, Ramon; Brunet, Joan; Menendez, Javier A

    2007-10-01

    Elucidating the mechanisms underlying resistance to the human epidermal growth factor receptor 2 (HER2)-targeted antibody trastuzumab (Tzb; Herceptin) is a major challenge that is beginning to be addressed. This dilemma is becoming increasingly important as recent studies strongly support a role for Tzb in the adjuvant setting for HER2-overexpressing early-stage breast cancers. We previously reported that pharmacological and RNA interference-induced inhibition of tumor-associated fatty acid synthase (FASN; Oncogenic antigen-519), a key metabolic enzyme catalyzing the synthesis of long-chain saturated fatty acids, drastically down-regulates HER2 expression in human breast cancer cells bearing HER2 gene amplification. Given that FASN blockade was found to suppress HER2 overexpression by attenuating the promoter activity of the HER2 gene, we here envisioned that this mechanism of action may represent a valuable strategy in breast cancers that have progressed while under Tzb. We created a preclinical model of Tzb resistance by continuously growing HER2-overexpressing SKBR3 breast cancer cells in the presence of clinically relevant concentrations of Tzb (20-185 microg/ml Tzb). This pool of Tzb-conditioned SKBR3 cells, which optimally grows now in the presence of 100 microg/ml trastuzumab (SKBR3/Tzb100 cells), exhibited HER2 levels notably higher (approximately 2-fold) than those found in SKBR3 parental cells. Real-time polymerase chain reaction studies showed that up-regulation of HER2 mRNA levels closely correlated with HER2 protein up-regulation in SKBR3/Tzb100 cells, thus suggesting that 'HER2 super-expression' upon acquisition of autoresistance to Tzb resulted, at least in part, from up-regulatory effects in the transcriptional rate of the HER2 gene. SKBR3/Tzb100 cells did not exhibit cross-resistance to C75, a small-compound specifically inhibiting FASN activity. On the contrary, SKBR3/Tzb100 cells showed a remarkably increased sensitivity (approximately 3-fold) to

  18. Postnatal ethanol exposure alters levels of 2-arachidonylglycerol-metabolizing enzymes and pharmacological inhibition of monoacylglycerol does not cause neurodegeneration in neonatal mice

    PubMed Central

    Subbanna, Shivakumar; Psychoyos, Delphine; Xie, Shan; Basavarajappa, Balapal S.

    2015-01-01

    The consumption of ethanol by pregnant women may cause neurological abnormalities, affecting learning and memory processes in children, and are collectively described as fetal alcohol spectrum disorders (FASDs). However, the molecular mechanisms underlying these changes are still poorly understood. In our previous studies, we found that ethanol treatment of postnatal day 7 (P7) mice significantly enhances anandamide (AEA) levels but not 2-arachidonylglycerol (2-AG) levels and induces widespread neurodegeneration, but the reason for the lack of significant effects of ethanol on the 2-AG level is unknown. In this study, we examined developmental changes in diacylglycerol lipase-α, β (DAGL-α and β) and monoacylglycerol lipase (MAGL). We found that the levels of these proteins were significantly higher in adult brains compared to those detected early in brain development. Next, we examined the influence of P7 ethanol treatment on these enzymes, finding that it differentially altered the DAGL-α protein and mRNA levels but consistently enhanced those of the DAGL-β. Interestingly, the ethanol treatment enhanced MAGL protein and mRNA levels. Inhibition of MAGL with KML29 failed to induce neurodegeneration in P7 mice. Collectively, these findings suggest that ethanol significantly activates DAGL-β and MAGL in the neonatal brain, resulting in no net change in 2-AG levels. PMID:25857698

  19. Postnatal ethanol exposure alters levels of 2-arachidonylglycerol-metabolizing enzymes and pharmacological inhibition of monoacylglycerol lipase does not cause neurodegeneration in neonatal mice.

    PubMed

    Subbanna, Shivakumar; Psychoyos, Delphine; Xie, Shan; Basavarajappa, Balapal S

    2015-07-01

    The consumption of ethanol by pregnant women may cause neurological abnormalities, affecting learning and memory processes in children, and are collectively described as fetal alcohol spectrum disorders. However, the molecular mechanisms underlying these changes are still poorly understood. In our previous studies, we found that ethanol treatment of postnatal day 7 (P7) mice significantly enhances the anandamide levels but not the 2-arachidonylglycerol (2-AG) levels and induces widespread neurodegeneration, but the reason for the lack of significant effects of ethanol on the 2-AG level is unknown. In this study, we examined developmental changes in diacylglycerol lipase-α, β (DAGL-α and β) and monoacylglycerol lipase (MAGL). We found that the levels of these proteins were significantly higher in adult brains compared to those detected early in brain development. Next, we examined the influence of P7 ethanol treatment on these enzymes, finding that it differentially altered the DAGL-α protein and mRNA levels but consistently enhanced those of the DAGL-β. Interestingly, the ethanol treatment enhanced MAGL protein and mRNA levels. Inhibition of MAGL with KML29 failed to induce neurodegeneration in P7 mice. Collectively, these findings suggest that ethanol significantly activates DAGL-β and MAGL in the neonatal brain, resulting in no net change in 2-AG levels.

  20. [Pharmacological treatment of obesity].

    PubMed

    Gomis Barbará, R

    2004-01-01

    The pharmacological treatment of obesity should be considered when cannot be achieved a 10% weight loss with diet therapy and physical activity. The drugs effective in obesity treatment may act by different mechanisms such as reduction in food intake, inhibition of fat absorption, increase of thermogenesis and stimulation of adipocyte apoptosis. At present, we only have two marketed drugs for obesity treatment. Sibutramine is an inhibitor of norepinephrine, dopamine and serotonina reuptake which inhibits food intake and increases thermogenesis. Sibutramine administration for a year can induce a weight loss of 4-7%. Its main side effects are hypertension, headache, insomnia and constipation. Orlistat is an inhibitor of pancreatic lipase which is able to block the absorption of 30% of ingested fat. Its administration induces weight loss and reduction of ulterior weight regain. Also, this drug improves hypertension dyslipdaemia and helps to prevent diabetes in 52% of cases when administered over four years. The increase in frequency of stools and interference with vitamin absorption are its main side effects. Glucagon-like peptide 1, which increases insulin sensitivity and satiety, adiponectin and PPAR-gamma agonists which reduce insulin resistance and modulates adipocyte generation are the basis for future therapeutic approaches of obesity. Phosphatase inhibitors induce PPAR-gamma phosphorylation and UCP-1 expression leading to an increase in thermogenesis and reduction in appetite.

  1. Pharmacological inhibition of myostatin/TGF-β receptor/pSmad3 signaling rescues muscle regenerative responses in mouse model of type 1 diabetes

    PubMed Central

    Jeong, Jaemin; Conboy, Michael J; Conboy, Irina M

    2013-01-01

    Aim: To study the influence of acute experimental diabetes on the regenerative potential of muscle stem (satellite) cells in mice. Methods: Male C57BL/6 young mice were injected with a single dose of streptozotocin (STZ, 180 mg/kg, ip) to induce diabetes. The diabetic mice were treated with insulin (0.75 U/kg, ip), follistatin (12 μg/kg, im) or Alk5 inhibitor (5 μmol/L per kg, sc) once a day. On the first day when high glucose levels were found, cardiotoxin (CTX) was focally injected into tibialis anterior and gastronemius muscles of the mice. The muscles were harvested 3 d and 5 d after CTX injection, and myofibers and satellite cells were isolated. Quantitative ex-vivo and in-vivo assays of myogenic potential were used to evaluate the muscle regenerative responses. Results: The satellite cells from the diabetic mice 3 d after CTX injection fail to activate, and the repair of muscle deteriorates, resembling that observed in old control mice. Furthermore, the satellite cells have excessive levels of myostatin, TGF-β receptor 1, pSmad3 and the cell cycle inhibitor p15, while the level of TGF-β1 remain unchanged. Treatment of the diabetic mice with insulin rescued muscle regenerative responses, and restored the expression levels of myostatin, TGF-β receptor 1, pSmad3, and p15 to those similar of healthy controls. Treatment of the diabetic mice with the myostatin antagonist follistatin, or with the Alk5 inhibitor of TGF-β receptor 1 (which did not diminish the blood glucose levels) rescued muscle regenerative responses and attenuated the myostatin/TGFβ receptor/pSmad3 signaling. Conclusion: The muscle regenerative responses are incapacitated and repair of the tissue fails within hours after the initiation of hyperglycemia in a mouse model of type 1 diabetes, but stem cell function is rescued by insulin, as well as follistatin or an Alk5 inhibitor that blocks TGF-β receptor signaling. PMID:23770987

  2. Pharmacological Inhibition of Caspase and Calpain Proteases: A Novel Strategy to Enhance the Homing Responses of Cord Blood HSPCs during Expansion

    PubMed Central

    V. M., Sangeetha; Kadekar, Darshana; Kale, Vaijayanti P.; Limaye, Lalita S.

    2012-01-01

    Background Expansion of hematopoietic stem/progenitor cells (HSPCs) is a well-known strategy employed to facilitate the transplantation outcome. We have previously shown that the prevention of apoptosis by the inhibition of cysteine proteases, caspase and calpain played an important role in the expansion and engraftment of cord blood (CB) derived HSPCs. We hypothesize that these protease inhibitors might have maneuvered the adhesive and migratory properties of the cells rendering them to be retained in the bone marrow for sustained engraftment. The current study was aimed to investigate the mechanism of the homing responses of CB cells during expansion. Methodology/Principal Findings CB derived CD34+ cells were expanded using a combination of growth factors with and without Caspase inhibitor -zVADfmk or Calpain 1 inhibitor- zLLYfmk. The cells were analyzed for the expression of homing-related molecules. In vitro adhesive/migratory interactions and actin polymerization dynamics of HSPCs were assessed. In vivo homing assays were carried out in NOD/SCID mice to corroborate these observations. We observed that the presence of zVADfmk or zLLYfmk (inhibitors) caused the functional up regulation of CXCR4, integrins, and adhesion molecules, reflecting in a higher migration and adhesive interactions in vitro. The enhanced actin polymerization and the RhoGTPase protein expression complemented these observations. Furthermore, in vivo experiments showed a significantly enhanced homing to the bone marrow of NOD/SCID mice. Conclusion/Significance Our present study reveals another novel aspect of the regulation of caspase and calpain proteases in the biology of HSPCs. The priming of the homing responses of the inhibitor-cultured HSPCs compared to the cytokine-graft suggests that the modulation of these proteases may help in overcoming the major homing defects prevalent in the expansion cultures thereby facilitating the manipulation of cells for transplant procedures. PMID

  3. Initial HIV-1 antigen-specific CD8+ T cells in acute HIV-1 infection inhibit transmitted/founder virus replication.

    PubMed

    Freel, Stephanie A; Picking, Ralph A; Ferrari, Guido; Ding, Haitao; Ochsenbauer, Christina; Kappes, John C; Kirchherr, Jennifer L; Soderberg, Kelly A; Weinhold, Kent J; Cunningham, Coleen K; Denny, Thomas N; Crump, John A; Cohen, Myron S; McMichael, Andrew J; Haynes, Barton F; Tomaras, Georgia D

    2012-06-01

    CD8-mediated virus inhibition can be detected in HIV-1-positive subjects who naturally control virus replication. Characterizing the inhibitory function of CD8(+) T cells during acute HIV-1 infection (AHI) can elucidate the nature of the CD8(+) responses that can be rapidly elicited and that contribute to virus control. We examined the timing and HIV-1 antigen specificity of antiviral CD8(+) T cells during AHI. Autologous and heterologous CD8(+) T cell antiviral functions were assessed longitudinally during AHI in five donors from the CHAVI 001 cohort using a CD8(+) T cell-mediated virus inhibition assay (CD8 VIA) and transmitted/founder (T/F) viruses. Potent CD8(+) antiviral responses against heterologous T/F viruses appeared during AHI at the first time point sampled in each of the 5 donors (Fiebig stages 1/2 to 5). Inhibition of an autologous T/F virus was durable to 48 weeks; however, inhibition of heterologous responses declined concurrent with the resolution of viremia. HIV-1 viruses from 6 months postinfection were more resistant to CD8(+)-mediated virus inhibition than cognate T/F viruses, demonstrating that the virus escapes early from CD8(+) T cell-mediated inhibition of virus replication. CD8(+) T cell antigen-specific subsets mediated inhibition of T/F virus replication via soluble components, and these soluble responses were stimulated by peptide pools that include epitopes that were shown to drive HIV-1 escape during AHI. These data provide insights into the mechanisms of CD8-mediated virus inhibition and suggest that functional analyses will be important for determining whether similar antigen-specific virus inhibition can be induced by T cell-directed vaccine strategies.

  4. Ayahuasca: Pharmacology, neuroscience and therapeutic potential.

    PubMed

    Domínguez-Clavé, Elisabet; Soler, Joaquim; Elices, Matilde; Pascual, Juan C; Álvarez, Enrique; de la Fuente Revenga, Mario; Friedlander, Pablo; Feilding, Amanda; Riba, Jordi

    2016-09-01

    Ayahuasca is the Quechua name for a tea obtained from the vine Banisteriopsis caapi, and used for ritual purposes by the indigenous populations of the Amazon. The use of a variation of the tea that combines B. caapi with the leaves of the shrub Psychotria viridis has experienced unprecedented expansion worldwide for its psychotropic properties. This preparation contains the psychedelic 5-HT2A receptor agonist N,N-dimethyltryptamine (DMT) from P. viridis, plus β-carboline alkaloids with monoamine-oxidase-inhibiting properties from B. caapi. Acute administration induces a transient modified state of consciousness characterized by introspection, visions, enhanced emotions and recollection of personal memories. A growing body of evidence suggests that ayahuasca may be useful to treat substance use disorders, anxiety and depression. Here we review the pharmacology and neuroscience of ayahuasca, and the potential psychological mechanisms underlying its therapeutic potential. We discuss recent findings indicating that ayahuasca intake increases certain mindfulness facets related to acceptance and to the ability to take a detached view of one's own thoughts and emotions. Based on the available evidence, we conclude that ayahuasca shows promise as a therapeutic tool by enhancing self-acceptance and allowing safe exposure to emotional events. We postulate that ayahuasca could be of use in the treatment of impulse-related, personality and substance use disorders and also in the handling of trauma. More research is needed to assess the full potential of ayahuasca in the treatment of these disorders.

  5. Androgen metabolism in oyster Crassostrea gigas: evidence for 17beta-HSD activities and characterization of an aromatase-like activity inhibited by pharmacological compounds and a marine pollutant.

    PubMed

    Le Curieux-Belfond, O; Moslemi, S; Mathieu, M; Séralini, G E

    2001-10-01

    The annual reproductive cycle of oyster Crassostrea gigas depends on environmental factors, but its endocrine regulations are still unknown. Sexual steroids play important roles at this level in vertebrates, and some estradiol effects have been described in invertebrates such as bivalve mollusks. To question these roles in invertebrates, we studied androgen metabolism in C. gigas. Incubations of tissue homogenates with 14C-steroids such as androstenedione (A), testosterone (T), estrone (E1) and estradiol (E2), followed by TLC and HPLC, provide evidence for 17beta-hydroxysteroid dehydrogenases (17beta-HSDs, conversions of A into T, T into A, E1 into E2 and E2 into E1) and aromatase-like (A into E1) activities. The latter activity was further characterized by tritiated water release assay; it was time- and temperature-dependent. Furthermore, this oyster aromatase-like activity was inhibited by 4-hydroxyandrostenedione (IC(50) 0.456 microM) and by other pharmacological compounds including specific cytochrome P450 inhibitors (MR20494, miconazole) and a marine pollutant (tributyltin).

  6. Inhibition of P38 MAPK Downregulates the Expression of IL-1β to Protect Lung from Acute Injury in Intestinal Ischemia Reperfusion Rats

    PubMed Central

    Zheng, De-Yi; Zhou, Min; Jin, Jiao; He, Mu; Wang, Yi; Du, Jiao; Xiao, Xiang-Yang; Li, Ping-Yang; Ye, Ai-Zhu; Liu, Jia; Wang, Ting-Hua

    2016-01-01

    Acute lung injury (ALI) induced by intestinal ischemia/reperfusion (II/R) has high incidence and mortality, in which IL-1β was essential for the full development of ALI. However, the detailed regulating mechanism for this phenomenon remains to be unclear. The purpose of this study was to investigate whether inhibition of P38 MAPK could downregulate the expression of IL-1β to protect lung from acute injury in II/R rats. Here, we found that the level of pulmonary edema at 16 hours after operation (hpo) was obviously enhanced compared to that in 8hpo and sham groups. Immunofluorescent staining demonstrated that IL-1β and P38 MAPK were detected in lung tissues. And rats with II/R have the highest translation level for IL-1β and phosphorylation of P38 MAPK in lung tissues at 16hpo compared with 8hpo and sham groups. Moreover, administration of SB239063, an inhibitor of P38 α and β, could effectively downregulate the expressions of IL-1β and protects lung tissues from injury in II/R rats. Our findings indicate that the inhibition of P38 α and β may downregulate the expression of IL-1β to protect lung from acute injury in II/R, which could be used as a potential target for reducing ALI induced by II/R in the future clinical trial. PMID:26980948

  7. Acetylcholinesterase Inhibitors: Pharmacology and Toxicology

    PubMed Central

    Čolović, Mirjana B; Krstić, Danijela Z; Lazarević-Pašti, Tamara D; Bondžić, Aleksandra M; Vasić, Vesna M

    2013-01-01

    Acetylcholinesterase is involved in the termination of impulse transmission by rapid hydrolysis of the neurotransmitter acetylcholine in numerous cholinergic pathways in the central and peripheral nervous systems. The enzyme inactivation, induced by various inhibitors, leads to acetylcholine accumulation, hyperstimulation of nicotinic and muscarinic receptors, and disrupted neurotransmission. Hence, acetylcholinesterase inhibitors, interacting with the enzyme as their primary target, are applied as relevant drugs and toxins. This review presents an overview of toxicology and pharmacology of reversible and irreversible acetylcholinesterase inactivating compounds. In the case of reversible inhibitors being commonly applied in neurodegenerative disorders treatment, special attention is paid to currently approved drugs (donepezil, rivastigmine and galantamine) in the pharmacotherapy of Alzheimer’s disease, and toxic carbamates used as pesticides. Subsequently, mechanism of irreversible acetylcholinesterase inhibition induced by organophosphorus compounds (insecticides and nerve agents), and their specific and nonspecific toxic effects are described, as well as irreversible inhibitors having pharmacological implementation. In addition, the pharmacological treatment of intoxication caused by organophosphates is presented, with emphasis on oxime reactivators of the inhibited enzyme activity administering as causal drugs after the poisoning. Besides, organophosphorus and carbamate insecticides can be detoxified in mammals through enzymatic hydrolysis before they reach targets in the nervous system. Carboxylesterases most effectively decompose carbamates, whereas the most successful route of organophosphates detoxification is their degradation by corresponding phosphotriesterases. PMID:24179466

  8. Acute SGLT inhibition normalizes O2 tension in the renal cortex but causes hypoxia in the renal medulla in anaesthetized control and diabetic rats.

    PubMed

    O'Neill, Julie; Fasching, Angelica; Pihl, Liselotte; Patinha, Daniela; Franzén, Stephanie; Palm, Fredrik

    2015-08-01

    Early stage diabetic nephropathy is characterized by glomerular hyperfiltration and reduced renal tissue Po2. Recent observations have indicated that increased tubular Na(+)-glucose linked transport (SGLT) plays a role in the development of diabetes-induced hyperfiltration. The aim of the present study was to determine how inhibition of SLGT impacts upon Po2 in the diabetic rat kidney. Diabetes was induced by streptozotocin in Sprague-Dawley rats 2 wk before experimentation. Renal hemodynamics, excretory function, and renal O2 homeostasis were measured in anesthetized control and diabetic rats during baseline and after acute SGLT inhibition using phlorizin (200 mg/kg ip). Baseline arterial pressure was similar in both groups and unaffected by SGLT inhibition. Diabetic animals displayed reduced baseline Po2 in both the cortex and medulla. SGLT inhibition improved cortical Po2 in the diabetic kidney, whereas it reduced medullary Po2 in both groups. SGLT inhibition reduced Na(+) transport efficiency [tubular Na(+) transport (TNa)/renal O2 consumption (Qo2)] in the control kidney, whereas the already reduced TNa/Qo2 in the diabetic kidney was unaffected by SGLT inhibition. In conclusion, these data demonstrate that when SGLT is inhibited, renal cortex Po2 in the diabetic rat kidney is normalized, which implies that increased proximal tubule transport contributes to the development of hypoxia in the diabetic kidney. The reduction in medullary Po2 in both control and diabetic kidneys during the inhibition of proximal Na(+) reabsorption suggests the redistribution of active Na(+) transport to less efficient nephron segments, such as the medullary thick ascending limb, which results in medullary hypoxia.

  9. Pharmacological aspects of the safety of gliflozins.

    PubMed

    Faillie, Jean-Luc

    2017-04-01

    Sodium-glucose transporter 2 (SGLT2) inhibitors, also known as gliflozins, are a new class of orally active drugs used in the management of type 2 diabetes. By inhibiting the SGLT responsible for the reabsorption of glucose from the kidney, their use aims primarily to induce glycosuria and, as a consequence, lower glycemic levels. However, their specific mechanism of action involves other pharmacodynamic consequences including potentially harmful adverse reactions. This manuscript reviews the physiological and pharmacological background behind inhibition of SGLTs, and discusses the pharmacological aspects of the safety of gliflozins.

  10. Curative Effects of Thiacremonone against Acetaminophen-Induced Acute Hepatic Failure via Inhibition of Proinflammatory Cytokines Production and Infiltration of Cytotoxic Immune Cells and Kupffer Cells

    PubMed Central

    Kim, Yu Ri; Ban, Jung Ok; Yoo, Hwan Soo; Lee, Yong Moon; Yoon, Yeo Pyo; Eum, So Young; Jeong, Heon Sang; Yoon, Do-young; Han, Sang Bae; Hong, Jin Tae

    2013-01-01

    High doses of acetaminophen (APAP; N-acetyl-p-aminophenol) cause severe hepatotoxicity after metabolic activation by cytochrome P450 2E1. This study was undertaken to examine the preventive effects of thiacremonone, a compound extracted from garlic, on APAP-induced acute hepatic failure in male C57BL/6J. Mice received with 500 mg/kg APAP after a 7-day pretreatment with thiacremonone (10–50 mg/kg). Thiacremonone inhibited the APAP-induced serum ALT and AST levels in a dose-dependent manner, and markedly reduced the restricted area of necrosis and inflammation by administration of APAP. Thiacremonone also inhibited the APAP-induced depletion of intracellular GSH, induction of nitric oxide, and lipid peroxidation as well as expression of P450 2E1. After APAP injection, the numbers of Kupffer cells, natural killer cells, and cytotoxic T cells were elevated, but the elevated cell numbers in the liver were reduced in thiacremonone pretreated mice. The expression levels of I-309, M-CSF, MIG, MIP-1α, MIP-1β, IL-7, and IL-17 were increased by APAP treatment, which were inhibited in thiacremonone pretreated mice. These data indicate that thiacremonone could be a useful agent for the treatment of drug-induced hepatic failure and that the reduction of cytotoxic immune cells as well as proinflammatory cytokine production may be critical for the prevention of APAP-induced acute liver toxicity. PMID:23935693

  11. Targeting the PI3K/AKT pathway via GLI1 inhibition enhanced the drug sensitivity of acute myeloid leukemia cells

    PubMed Central

    Liang, Hui; Zheng, Qi-Li; Fang, Peng; Zhang, Jian; Zhang, Tuo; Liu, Wei; Guo, Min; Robinson, Christopher L.; Chen, Shui-bing; Chen, Xiao-Ping; Chen, Fang-Ping; Zeng, Hui

    2017-01-01

    Combination targeted therapy is commonly used to treat acute myeloid leukemia (AML) patients, particularly in refractory/relapse (RR) population. However, concerns have been raised regarding the safety and patient tolerance of combination chemotherapy. It is critical to choose the appropriate treatment for precision therapy. We performed genome-wide RNA profiling using RNA-Seq to compare the RR group and the complete remission (CR) group (a total of 42 adult AML patients). The Hedgehog (Hh) and PI3K/AKT pathways were upregulated in the RR population, which was further confirmed by western blot and/or qPCR. Overexpression of GLI1 in AML cells led to increased AKT phosphorylation and decreased drug sensitivity, which was attenuated by GLI1 inhibition. By contrast, neither the expression of GLI1 nor apoptosis in response to Ara-C treatment of AML cells was significantly affected by PI3K inhibition. Furthermore, co-inhibition of GLI1 and PI3K induced apoptosis of hematopoietic stem/progenitor cells (HSPCs), which raised serious concerns about the side effects of this treatment. These results indicated that GLI1 inhibition alone, but not combined inhibition, is sufficient to enhance AML drug sensitivity, which provides a novel therapeutic strategy for AML treatment. PMID:28098170

  12. Preclinical pharmacology and opioid combinations.

    PubMed

    Pasternak, Gavril W

    2012-03-01

    Although effective alone, opioids are often used in combination with other drugs for relief of moderate to severe pain. Guidelines for acute perioperative pain recommend the use of multimodal therapy for pain management, although combinations of opioids are not specifically recommended. Mu opioid drugs include morphine, heroin, fentanyl, methadone, and morphine 6β-glucuronide (M6G). Their mechanism of action is complex, resulting in subtle pharmacological differences among them and with unpredictable differences in their potency, effectiveness, and tolerability among patients. Highly selective mu opioids do not bind to a single receptor. Rather, they interact with a large number of mu receptor subtypes with different activation profiles for the various drugs. Thus, mu-receptor-based drugs are not all the same and it may be possible to utilize these differences for enhanced pain control in a clinical setting. These differences among the drugs raise the question of whether combinations might result in better pain relief with fewer side effects. This concept has already been demonstrated between two mu opioids in preclinical studies and clinical trials on other combinations are ongoing. This article reviews the current state of knowledge about mu opioid receptor pharmacology, summarizes preclinical evidence for synergy from opioid combinations, and highlights the complex nature of the mu opioid receptor pharmacology.

  13. Captopril pretreatment protects the lung against severe acute pancreatitis induced injury via inhibiting angiotensin II production and suppressing Rho/ROCK pathway.

    PubMed

    Yu, Qi-Hong; Guo, Jie-Fang; Chen, Yan; Guo, Xiao-Rong; Du, Yi-Qi; Li, Zhao-Shen

    2016-09-01

    Acute pancreatitis (AP) usually causes acute lung injury, which is also known as acute pancreatitis associated lung injury (APALI). This study aimed to investigate whether captopril pretreatment was able to protect lung against APALI via inhibiting angiotensin II (Ang II) production and suppressing Rho/ROCK (Rho kinase) pathway in rats. Severe AP (SAP) was introduced to rats by bile-pancreatic duct retrograde injection of 5% sodium taurocholate. Rats were randomly divided into three groups. In the sham group, sham operation was performed; in the SAP group, SAP was introduced; in the pre-cpl + SAP group, rats were intragastrically injected with 5 mg/kg captopril 1 hour prior to SAP induction. Pathological examination of the lung and pancreas, evaluation of pulmonary vascular permeability by wet/dry ratio and Evans Blue staining, detection of serum amylase, Western blot assay for Ang II receptor type 1 (AT1), RhoA, ROCK (Rho kinase), and MLCK (myosin light chain kinase) were performed after the animals were sacrificed at 24 hours. After the surgery, characteristic findings of pancreatitis were observed, accompanied by lung injury. The serum amylase, Ang II, and lung expression of AT1, RhoA, ROCK, and MLCK increased dramatically in SAP rats. However, captopril pretreatment improved the histological changes, reduced the pathological score of the pancreas and lung, inhibited serum amylase and Ang II production, and decreased expression of AT1, RhoA, ROCK, and MLCK in the lung. These findings suggest that captopril pretreatment is able to protect the lung against APALI, which is, at least partially, related to the inhibition of Ang II production and the suppression of the Rho/ROCK pathway.

  14. Pharmacology of appetite suppression.

    PubMed

    Halford, J C; Blundell, J E

    2000-01-01

    Despite a rising worldwide epidemic of obesity there is currently only a very small number of anti-obesity drugs available to manage the problem. Large numbers of differing pharmacological agents reliably produce a reduction in food intake when administered acutely to animals, and when administered chronically they result in a significant decrease in body mass. Behavioural analysis of drug-induced anorexia in animals demonstrates that various compounds profoundly effect feeding behaviour in differing ways. This indicates the variety of mechanisms by which pharmacological agents can induce changes in food intake, body weight and eventually body composition. Some of the same drugs produce decreases in food intake and weight loss in humans. Some of these drugs do so by modifying the functioning of the appetite system as measured by subjective changes in feelings of hunger and fullness (indices of satiety). Such drugs can be considered as "appetite suppressants" with clinical potential as anti-obesity agents. Other drugs induce changes in food intake and body weight through various physiological mechanisms inducing feelings of nausea or even by side effect related malaise. Of the drugs considered suitable candidates for appetite suppressants are agents which act via peripherally satiety peptide systems (such as CCK, Bombesin/GRP, Enterostatin and GLP-1), or alter the CNS levels of various hypothalamic neuropeptides (NPY, Galanin, Orexin and Melanocortins) or levels of the key CNS appetite monoamine neurotransmitters such as serotonin (5-HT) and noradrenaline (NA). Recently, the hormone leptin has been regarded as a hormonal signal linking adipose tissue status with a number of key central nervous system circuits. The peptide itself stimulates leptin receptors and it links with POMC and MC-4 receptors. These receptors may also provide drug targets for the control of appetite. Any changes induced by a potential appetite suppressant should be considered in terms of the (i

  15. SphK1 inhibitor II (SKI-II) inhibits acute myelogenous leukemia cell growth in vitro and in vivo

    SciTech Connect

    Yang, Li; Weng, Wei; Sun, Zhi-Xin; Fu, Xian-Jie; Ma, Jun Zhuang, Wen-Fang

    2015-05-15

    Previous studies have identified sphingosine kinase 1 (SphK1) as a potential drug target for treatment of acute myeloid leukemia (AML). In the current study, we investigated the potential anti-leukemic activity of a novel and specific SphK1 inhibitor, SKI-II. We demonstrated that SKI-II inhibited growth and survival of human AML cell lines (HL-60 and U937 cells). SKI-II was more efficient than two known SphK1 inhibitors SK1-I and FTY720 in inhibiting AML cells. Meanwhile, it induced dramatic apoptosis in above AML cells, and the cytotoxicity by SKI-II was almost reversed by the general caspase inhibitor z-VAD-fmk. SKI-II treatment inhibited SphK1 activation, and concomitantly increased level of sphingosine-1-phosphate (S1P) precursor ceramide in AML cells. Conversely, exogenously-added S1P protected against SKI-II-induced cytotoxicity, while cell permeable short-chain ceramide (C6) aggravated SKI-II's lethality against AML cells. Notably, SKI-II induced potent apoptotic death in primary human AML cells, but was generally safe to the human peripheral blood mononuclear cells (PBMCs) isolated from healthy donors. In vivo, SKI-II administration suppressed growth of U937 leukemic xenograft tumors in severe combined immunodeficient (SCID) mice. These results suggest that SKI-II might be further investigated as a promising anti-AML agent. - Highlights: • SKI-II inhibits proliferation and survival of primary and transformed AML cells. • SKI-II induces apoptotic death of AML cells, but is safe to normal PBMCs. • SKI-II is more efficient than two known SphK1 inhibitors in inhibiting AML cells. • SKI-II inhibits SphK1 activity, while increasing ceramide production in AML cells. • SKI-II dose-dependently inhibits U937 xenograft growth in SCID mice.

  16. Macrophages and galectin 3 play critical roles in CVB3-induced murine acute myocarditis and chronic fibrosis.

    PubMed

    Jaquenod De Giusti, Carolina; Ure, Agustín E; Rivadeneyra, Leonardo; Schattner, Mirta; Gomez, Ricardo M

    2015-08-01

    Macrophage influx and galectin 3 production have been suggested as major players driving acute inflammation and chronic fibrosis in many diseases. However, their involvement in the pathogenesis of viral myocarditis and subsequent cardiomyopathy are unknown. Our aim was to characterise the role of macrophages and galectin 3 on survival, clinical course, viral burden, acute pathology, and chronic fibrosis in coxsackievirus B3 (CVB3)-induced myocarditis. Our results showed that C3H/HeJ mice infected with CVB3 and depleted of macrophages by liposome-encapsulated clodronate treatment compared with infected untreated mice presented higher viral titres but reduced acute myocarditis and chronic fibrosis, compared with untreated infected mice. Increased galectin 3 transcriptional and translational expression levels correlated with CVB3 infection in macrophages and in non-depleted mice. Disruption of the galectin 3 gene did not affect viral titres but reduced acute myocarditis and chronic fibrosis compared with C57BL/6J wild-type mice. Similar results were observed after pharmacological inhibition of galectin 3 with N-acetyl-d-lactosamine in C3H/HeJ mice. Our results showed a critical role of macrophages and their galectin 3 in controlling acute viral-induced cardiac injury and the subsequent fibrosis. Moreover, the fact that pharmacological inhibition of galectin 3 induced similar results to macrophage depletion regarding the degree of acute cardiac inflammation and chronic fibrosis opens up the possibility of new pharmacological strategies for viral myocarditis.

  17. [Pharmacological effects of hordenine].

    PubMed

    Hapke, H J; Strathmann, W

    1995-06-01

    Hordenine is an ingredient of some plants which are used as feed for animals, i.e. in sprouting barley. After ingestion of such feed hordenine may be detected in blood or urine of horses which in case of racing horses may be the facts of using prohibited compounds. Results of some experiments in pharmacological models show that hordenine is an indirectly acting adrenergic drug. It liberates norepinephrine from stores. In isolated organs and those structures with reduced epinephrine contents the hordenine-effect is only very poor. Experiments in intact animals (rats, dogs) show that hordenine has a positive inotropic effect upon the heart, increases systolic and diastolic blood pressure, peripheral blood flow volume, inhibits gut movements but has no effect upon the psychomotorical behaviour of mice. All effects are short and only possible after high doses which are not to be expected after ingestion of hordenine containing feed for horses. A measurable increase of the performance of racing horses is quite improbable.

  18. Super pharmacological levels of calcitriol (1,25-(OH)2D3) inhibits mineral deposition and decreases cell proliferation in a strain dependent manner in chicken mesenchymal stem cells undergoing osteogenic differentiation in vitro.

    PubMed

    Pande, Vivek V; Chousalkar, Kapil C; Bhanugopan, Marie S; Quinn, Jane C

    2015-11-01

    The biologically active form of vitamin D₃, calcitriol (1,25-(OH)₂D₃), plays a key role in mineral homeostasis and bone formation and dietary vitamin D₃deficiency is a major cause of bone disorders in poultry. Supplementary dietary cholecalciferol (25-hydroxyvitamin D, 25-OH), the precursor of calcitriol, is commonly employed to combat this problem; however, dosage must be carefully determined as excess dietary vitamin D can cause toxicity resulting in a decrease in bone calcification, hypercalcinemia and renal failure. Despite much research on the therapeutic administration of dietary vitamin D in humans, the relative sensitivity of avian species to exogenous vitamin D has not been well defined. In order to determine the effects of exogenous 1,25-(OH)₂D₃during avian osteogenesis, chicken bone marrow-derived mesenchymal stem cells (BM-MSCs) were exposed to varying doses of 1,25-(OH)₂D₃during in vitro osteogenic differentiation and examined for markers of early proliferation and osteogenic induction. Similar to humans and other mammals, poultry BM-MSCs were found to be highly sensitive to exogenous 1,25-(OH)₂D₃with super pharmacological levels exerting significant inhibition of mineralization and loss of cell proliferation in vitro. Strain related differences were apparent, with BM-MCSs derived from layers strains showing a higher level of sensitivity to 1,25-(OH)₂D₃than those from broilers. These data suggest that understanding species and strain specific sensitivities to 1,25-(OH)₂D₃is important for optimizing bone health in the poultry industry and that use of avian BM-MSCs are a useful tool for examining underlying effects of genetic variation in poultry.

  19. Pharmacology of Periodontal Disease.

    DTIC Science & Technology

    2014-09-26

    k 7RD-A157 116 PHARMRCOLOGY’ OF PERIODONTAL DISEASE(U) UNIVERSITY OF i/ I HEALTH SCIENCES/CHICAGO MEDICAL SCHOOL DEPT OF I PHARMACOLOGY S F HOFF 24...University of Health Sciences/The Chicago Medical School Department of 3333 Green Bay Road Telephone Pharmacology North Chicago, Illinois 60064...Region Bethesda, MD 20814-5044 • .RE: Annual Letter Report , ONR Contract #N00014-84-K-0562 " Pharmacology of Periodontal Disease" Dear Capt. Hancock

  20. The novel combination of dual mTOR inhibitor AZD2014 and pan-PIM inhibitor AZD1208 inhibits growth in acute myeloid leukemia via HSF pathway suppression.

    PubMed

    Harada, Masako; Benito, Juliana; Yamamoto, Shinichi; Kaur, Surinder; Arslan, Dirim; Ramirez, Santiago; Jacamo, Rodrigo; Platanias, Leonidas; Matsushita, Hiromichi; Fujimura, Tsutomu; Kazuno, Saiko; Kojima, Kensuke; Tabe, Yoko; Konopleva, Marina

    2015-11-10

    Mammalian target of rapamycin (mTOR) signaling is a critical pathway in the biology of acute myeloid leukemia (AML). Proviral integration site for moloney murine leukemia virus (PIM) serine/threonine kinase signaling takes part in various pathways exerting tumorigenic properties. We hypothesized that the combination of a PIM kinase inhibitor with an mTOR inhibitor might have complementary growth-inhibitory effects against AML. The simultaneous inhibition of the PIM kinase by pan-PIM inhibitor AZD1208 and of mTOR by selective mTORC1/2 dual inhibitor AZD2014 exerted anticancer properties in AML cell lines and in cells derived from primary AML samples with or without supportive stromal cell co-culture, leading to suppressed proliferation and increased apoptosis. The combination of AZD1208 and AZD2014 rapidly activated AMPKα, a negative regulator of translation machinery through mTORC1/2 signaling in AML cells; profoundly inhibited AKT and 4EBP1 activation; and suppressed polysome formation. Inhibition of both mTOR and PIM counteracted induction of heat-shock family proteins, uncovering the master negative regulation of heat shock factor 1 (HSF1), the dominant transcription factor controlling cellular stress responses. The novel combination of the dual mTOR inhibitor and pan-PIM inhibitor synergistically inhibited AML growth by effectively reducing protein synthesis through heat shock factor pathway suppression.

  1. Studies in neuroendocrine pharmacology

    NASA Technical Reports Server (NTRS)

    Maickel, R. P.

    1976-01-01

    The expertise and facilities available within the Medical Sciences Program section on Pharmacology were used along with informational input from various NASA sources to study areas relevant to the manned space effort. Topics discussed include effects of drugs on deprivation-induced fluid consumption, brain biogenic amines, biochemical responses to stressful stimuli, biochemical and behavioral pharmacology of amphetamines, biochemical and pharmacological studies of analogues to biologically active indole compounds, chemical pharmacology: drug metabolism and disposition, toxicology, and chemical methodology. Appendices include a bibliography, and papers submitted for publication or already published.

  2. Principles of safety pharmacology.

    PubMed

    Pugsley, M K; Authier, S; Curtis, M J

    2008-08-01

    Safety Pharmacology is a rapidly developing discipline that uses the basic principles of pharmacology in a regulatory-driven process to generate data to inform risk/benefit assessment. The aim of Safety Pharmacology is to characterize the pharmacodynamic/pharmacokinetic (PK/PD) relationship of a drug's adverse effects using continuously evolving methodology. Unlike toxicology, Safety Pharmacology includes within its remit a regulatory requirement to predict the risk of rare lethal events. This gives Safety Pharmacology its unique character. The key issues for Safety Pharmacology are detection of an adverse effect liability, projection of the data into safety margin calculation and finally clinical safety monitoring. This article sets out to explain the drivers for Safety Pharmacology so that the wider pharmacology community is better placed to understand the discipline. It concludes with a summary of principles that may help inform future resolution of unmet needs (especially establishing model validation for accurate risk assessment). Subsequent articles in this issue of the journal address specific aspects of Safety Pharmacology to explore the issues of model choice, the burden of proof and to highlight areas of intensive activity (such as testing for drug-induced rare event liability, and the challenge of testing the safety of so-called biologics (antibodies, gene therapy and so on.).

  3. Pretreatment with Fucoidan from Fucus vesiculosus Protected against ConA-Induced Acute Liver Injury by Inhibiting Both Intrinsic and Extrinsic Apoptosis

    PubMed Central

    Li, Jingjing; Chen, Kan; Li, Sainan; Liu, Tong; Wang, Fan; Xia, Yujing; Lu, Jie; Zhou, Yingqun; Guo, Chuanyong

    2016-01-01

    This study aimed to explore the effects of fucoidan from Fucus vesiculosus on concanavalin A (ConA)-induced acute liver injury in mice. Pretreatment with fucoidan protected liver function indicated by ALT, AST and histopathological changes by suppressing inflammatory cytokines, such as tumor necrosis factor alpha (TNF-α) and interferon gamma (IFN-γ). In addition, intrinsic and extrinsic apoptosis mediated by Bax, Bid, Bcl-2, Bcl-xL and Caspase 3, 8, and 9 were inhibited by fucoidan and the action was associated with the TRADD/TRAF2 and JAK2/STAT1 signal pathways. Our results demonstrated that fucoidan from Fucus vesiculosus alleviated ConA-induced acute liver injury via the inhibition of intrinsic and extrinsic apoptosis mediated by the TRADD/TRAF2 and JAK2/STAT1 pathways which were activated by TNF-α and IFN-γ. These findings could provide a potential powerful therapy for T cell-related hepatitis. PMID:27035150

  4. Protective Effect of Amygdalin on LPS-Induced Acute Lung Injury by Inhibiting NF-κB and NLRP3 Signaling Pathways.

    PubMed

    Zhang, Ao; Pan, Weiyun; Lv, Juan; Wu, Hui

    2017-03-16

    The acute lung injury (ALI) is a leading cause of morbidity and mortality in critically ill patients. Amygdalin is derived from the bitter apricot kernel, an efficacious Chinese herbal medicine. Although amygdalin is used by many cancer patients as an antitumor agent, there is no report about the effect of amygdalin on acute lung injury. Here we explored the protective effect of amygdalin on ALI using lipopolysaccharide (LPS)-induced murine model by detecting the lung wet/dry ratio, the myeloperoxidase (MPO) in lung tissues, inflammatory cells in the bronchoalveolar lavage fluid (BALF), inflammatory cytokines production, as well as NLRP3 and NF-κB signaling pathways. The results showed that amygdalin significantly reduced LPS-induced infiltration of inflammatory cells and the production of TNF-α, IL-1β, and IL-6 in the BALF. The activity of MPO and lung wet/dry ratio were also attenuated by amygdalin. Furthermore, the western blotting analysis showed that amygdalin remarkably inhibited LPS-induced NF-κB and NLRP3 activation. These findings indicate that amygdalin has a protective effect on LPS-induced ALI in mice. The mechanism may be related to the inhibition of NF-κB and NLRP3 signaling pathways.

  5. Acute toxicity of some synthetic cyanogens in rats: time-dependent cyanide generation and cytochrome oxidase inhibition in soft tissues after sub-lethal oral intoxication.

    PubMed

    Rao, Pooja; Singh, Poonam; Yadav, Shiv Kumar; Gujar, Niranjan L; Bhattacharya, Rahul

    2013-09-01

    Cyanogens include complex nitrile-containing compounds that can generate free cyanide of toxicological significance. Acute toxicity, time-dependent cyanide generation and cytochrome oxidase (CYTOX) inhibition in soft tissues, and urinary thiocyanate levels were measured after acute cyanogen intoxication in rats. Order of cyanogens in terms of LD₅₀ was: malononitrile (MCN)>propionitrile (PCN)≈sodium nitroprusside (SNP)>acrylonitrile (ACN)>succinonitrile (SCN)>acetonitrile (ATCN) for oral, and SNP>MCN>ACN>PCN>SCN>ATCN for intraperitoneal and subcutaneous routes. MCN was most toxic by oral (LD₅₀=66.4 mg/kg) and SNP by intraperitoneal (LD₅₀=16.7 mg/kg) and subcutaneous (LD₅₀=11.9 mg/kg) routes. Minimum survival time (25 min) was recorded after 4.0 LD₅₀ ATCN. Order of cyanogens (0.75 LD₅₀; oral) on the basis of maximum blood cyanide and time of peak cyanide generation were: ATCN>SNP>SCN>PCN>MCN>ACN, and MCN (30 min)inhibition and urinary thiocyanate levels. With the understanding of time-dependent toxicity of different cyanogens, suitable therapeutic windows can be designed for their management.

  6. Potential of the angiotensin receptor blockers (ARBs) telmisartan, irbesartan, and candesartan for inhibiting the HMGB1/RAGE axis in prevention and acute treatment of stroke.

    PubMed

    Kikuchi, Kiyoshi; Tancharoen, Salunya; Ito, Takashi; Morimoto-Yamashita, Yoko; Miura, Naoki; Kawahara, Ko-ichi; Maruyama, Ikuro; Murai, Yoshinaka; Tanaka, Eiichiro

    2013-09-13

    Stroke is a major cause of mortality and disability worldwide. The main cause of stroke is atherosclerosis, and the most common risk factor for atherosclerosis is hypertension. Therefore, antihypertensive treatments are recommended for the prevention of stroke. Three angiotensin receptor blockers (ARBs), telmisartan, irbesartan and candesartan, inhibit the expression of the receptor for advanced glycation end-products (RAGE), which is one of the pleiotropic effects of these drugs. High mobility group box 1 (HMGB1) is the ligand of RAGE, and has been recently identified as a lethal mediator of severe sepsis. HMGB1 is an intracellular protein, which acts as an inflammatory cytokine when released into the extracellular milieu. Extracellular HMGB1 causes multiple organ failure and contributes to the pathogenesis of hypertension, hyperlipidemia, diabetes mellitus, atherosclerosis, thrombosis, and stroke. This is the first review of the literature evaluating the potential of three ARBs for the HMGB1-RAGE axis on stroke therapy, including prevention and acute treatment. This review covers clinical and experimental studies conducted between 1976 and 2013. We propose that ARBs, which inhibit the HMGB1/RAGE axis, may offer a novel option for prevention and acute treatment of stroke. However, additional clinical studies are necessary to verify the efficacy of ARBs.

  7. Lentiviral vector-mediated RNA interference targeted against prohibitin inhibits apoptosis of the retinoic acid-resistant acute promyelocytic leukemia cell line NB4-R1.

    PubMed

    Liu, Yanfeng; He, Pengcheng; Zhang, Mei; Wu, Di

    2012-12-01

    To investigate the possibility of prohibitin (PHB) inhibition by lentiviral vector-mediated RNA interference (RNAi) and its influence on cell apoptosis in the retinoic acid-resistant acute promyelocytic leukemia cell line NB4-R1, a lentiviral vector encoding a short hairpin RNA (shRNA) targeted against PHB (pGCSIL-GFP-PHB) was constructed and transfected into the packaging cells 293T, and the viral supernatant was collected to transfect NB4-R1 cells. Quantitative real-time fluorescent PCR and western blotting were used to detect the expression levels of PHB. Flow cytometry and detection of enzymatic activity of caspase-3 by western blotting were employed to examine cell apoptosis. Our results provide evidence that the lentiviral vector pGCSIL-GFP-PHB was constructed successfully, and the PHB mRNA and the protein expression inhibitory rates were 90.3 and 95.8%, respectively. When compared to the control group, the activity of caspase-3 decreased significantly, which showed a 57.3% downregulation, and the apoptosis rate was reduced by 44.6% (P<0.05). In conclusion, downregulation of the PHB gene may inhibit apoptosis of NB4-R1 cells, and it is speculated that this was at least partly due to the downregulation of caspase-3, and PHB may be a novel target for gene therapy for retinoic acid-resistant acute promyelocytic leukemia.

  8. Acute and Chronic Toxicity, Cytochrome P450 Enzyme Inhibition, and hERG Channel Blockade Studies with a Polyherbal, Ayurvedic Formulation for Inflammation

    PubMed Central

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

    2015-01-01

    Ayurvedic plants are known for thousands of years to have anti-inflammatory and antiarthritic effect. We have recently shown that BV-9238, a proprietary formulation of Withania somnifera, Boswellia serrata, Zingiber officinale, and Curcuma longa, inhibits LPS-induced TNF-alpha and nitric oxide production from mouse macrophage and reduces inflammation in different animal models. To evaluate the safety parameters of BV-9238, we conducted a cytotoxicity study in RAW 264.7 cells (0.005–1 mg/mL) by MTT/formazan method, an acute single dose (2–10 g/kg bodyweight) toxicity study and a 180-day chronic study with 1 g and 2 g/kg bodyweight in Sprague Dawley rats. Some sedation, ptosis, and ataxia were observed for first 15–20 min in very high acute doses and hence not used for further chronic studies. At the end of 180 days, gross and histopathology, blood cell counts, liver and renal functions were all at normal levels. Further, a modest attempt was made to assess the effects of BV-9238 (0.5 µg/mL) on six major human cytochrome P450 enzymes and 3H radioligand binding assay with human hERG receptors. BV-9238 did not show any significant inhibition of these enzymes at the tested dose. All these suggest that BV-9238 has potential as a safe and well tolerated anti-inflammatory formulation for future use. PMID:25893199

  9. Phospholipase A2 inhibits cisplatin-induced acute kidney injury by modulating regulatory T cells by the CD206 mannose receptor.

    PubMed

    Kim, Hyunseong; Lee, Hyojung; Lee, Gihyun; Jang, Hyunil; Kim, Sung-Su; Yoon, Heera; Kang, Geun-Hyung; Hwang, Deok-Sang; Kim, Sun Kwang; Chung, Hwan-Suck; Bae, Hyunsu

    2015-09-01

    Previously, we found that Foxp3-expressing CD4(+) regulatory T (Treg) cells attenuate cisplatin-induced acute kidney injury in mice and that bee venom and its constituent phospholipase A2 (PLA2) are capable of modulating Treg cells. Here we tested whether PLA2 could inhibit cisplatin-induced acute kidney injury. As a result of treatment with PLA2, the population of Treg cells was significantly increased, both in vivo and in vitro. PLA2-injected mice showed reduced levels of serum creatinine, blood urea nitrogen, renal tissue damage, and pro-inflammatory cytokine production upon cisplatin administration. These renoprotective effects were abolished by depletion of Treg cells. Furthermore, PLA2 bound to CD206 mannose receptors on dendritic cells, essential for the PLA2-mediated protective effects on renal dysfunction. Interestingly, PLA2 treatment increased the secretion of IL-10 in the kidney from normal mice. Foxp3(+)IL-10(+) cells and CD11c(+)IL-10(+) cells were increased by PLA2 treatment. The anticancer effects of repeated administrations of a low dose of cisplatin were not affected by PLA2 treatment in a tumor-bearing model. Thus, PLA2 may prevent inflammatory responses in cisplatin-induced acute kidney injury by modulating Treg cells and IL-10 through the CD206 mannose receptor.

  10. Different reactivity to angiotensin II of peripheral and renal arteries in spontaneously hypertensive rats: effect of acute and chronic angiotensin converting enzyme inhibition

    NASA Technical Reports Server (NTRS)

    Guidi, E.; Hollenberg, N. K.

    1986-01-01

    We assessed renal blood flow and pressor responses to graded angiotensin II doses in spontaneously hypertensive (SHR) and Wistar-Kyoto (WKY) rats ingesting a diet containing 1.6% sodium basally and after acute and chronic angiotensin converting enzyme (ACE) inhibition with captopril. In the basal state the pressor response to angiotensin II was enhanced (P<0.0005) and the renal vascular response was blunted (P<0.005) in SHR compared with WKY rats. After acute captopril administration the pressor response was enhanced in both strains, and the difference between them was maintained, while the renal vascular response was enhanced in both, but more in SHR, so that the renal vascular response in the SHR became larger than in WKY (P<0.0001). Chronic captopril treatment blunted both pressor and renal responses in WKY rats, but only the pressor response in SHR. The renal vessels of SHR seem to be different from those of WKY rats in reaction to exogenous angiotensin II, and in response to both acute administration of captopril (probably acting through blockade of angiotensin II production) and chronic administration of captopril (probably acting mainly through accumulation of kinin or production of prostaglandins).

  11. Herbal SGR Formula Prevents Acute Ethanol-Induced Liver Steatosis via Inhibition of Lipogenesis and Enhancement Fatty Acid Oxidation in Mice

    PubMed Central

    Qiu, Ping; Li, Xiang; Kong, De-song; Li, Huan-zhou; Niu, Cong-cong; Pan, Su-hua

    2015-01-01

    Our previous study indicated that herbal SGR formula partially attenuates ethanol-induced fatty liver, but the underlying mechanisms remain unclear. In the present study, mice were pretreated with SGR (100 and 200 mg/kg/d bw) for 30 d before being exposed to ethanol (4.8 g/kg bw). The biochemical indices and histopathological changes were examined to evaluate the protective effects and to explore potential mechanisms by investigating the adiponectin, tumor necrosis factor-α (TNF-α), peroxisome proliferators-activated receptor-α (PPAR-α), sterol regulatory element binding protein-1c (SREBP-1c), adenosine monophosphate-activated protein kinase (AMPK), and so forth. Results showed that SGR pretreatment markedly inhibited acute ethanol-induced liver steatosis, significantly reduced serum and hepatic triglyceride (TG) level, and improved classic histopathological changes. SGR suppressed the protein expression of hepatic SREBP-1c and TNF-α and increased adiponectin, PPAR-α, and AMPK phosphorylation in the liver. Meanwhile, acute toxicity tests showed that no death or toxic side effects within 14 days were observed upon oral administration of the extracts at a dose of 16 g/kg body wt. These results demonstrate that SGR could protect against acute alcohol-induced liver steatosis without any toxic side effects. Therefore, our studies provide novel molecular insights into the hepatoprotective effect of SGR formula, which may be exploited as a therapeutic agent for ethanol-induced hepatosteatosis. PMID:26101535

  12. Riluzole But Not Melatonin Ameliorates Acute Motor Neuron Degeneration and Moderately Inhibits SOD1-Mediated Excitotoxicity Induced Disrupted Mitochondrial Ca2+ Signaling in Amyotrophic Lateral Sclerosis

    PubMed Central

    Jaiswal, Manoj Kumar

    2017-01-01

    intrinsic NADH fluorescence in HMNs in presence of riluzole when respiratory chain activity was inhibited by Na-azide. Riluzole’s inhibition of excitability and Ca2+ signaling may be due to its multiple effects on cellular function of mitochondria. Therefore formulating a drug therapy to stabilize mitochondria-related signaling pathways using riluzole might be a valuable approach for cell death protection in ALS. Taken together, the pharmacological profiles of the riluzole and melatonin strengthen the case that riluzole indeed can be used as a therapeutic agent in ALS whereas claims of the efficacy of melatonin alone need further investigation as it fail to show significant neuroprotection efficacy. PMID:28111541

  13. The Time-Course of Acute Changes in Corticospinal Excitability, Intra-Cortical Inhibition and Facilitation Following a Single-Session Heavy Strength Training of the Biceps Brachii

    PubMed Central

    Latella, Christopher; Hendy, Ashlee M.; Pearce, Alan J.; VanderWesthuizen, Dan; Teo, Wei-Peng

    2016-01-01

    Objective: The current understanding of acute neurophysiological responses to resistance training remains unclear. Therefore, we aimed to compare the time-course of acute corticospinal responses following a single-session heavy strength training (HST) of the biceps brachii (BB) muscle and provide quantifiable evidence based on the super-compensation model in an applied setting. Methods: Fourteen participants completed a counter-balanced, cross-over study that consisted of a single HST session (5 sets × 3 repetition maximum [RM]) of the BB and a control session (CON). Single- and paired-pulse transcranial magnetic stimulation (TMS) was used to measure changes in motor-evoked potential (MEP) amplitude, intra-cortical facilitation (ICF), short-interval intra-cortical inhibition (SICI) and long-interval intra-cortical inhibition (LICI). Additionally, maximal muscle compound wave (MMAX) and maximal voluntary isometric contraction (MVIC) of the BB were taken. All measures were taken at baseline, immediately post and at 10, 20, 30 min and 1, 2, 6, 24, 48 and 72 h post-training. Results: A significant reduction in MEP amplitude was observed immediately post training (P = 0.001), while MVIC (P < 0.001) and MMAX (P = 0.047) were reduced for up to 30 min post-training. An increase in MVIC (p < 0.001) and MMAX (p = 0.047) was observed at 6 h, while an increase in MEP amplitude (p = 0.014) was only observed at 48 and 72 h. No changes in SICI, ICF and LICI were observed. Conclusion: Our results suggest that: (1) acute changes in corticospinal measures returned to baseline in a shorter timeframe than the current super-compensation model (24–48 h) and (2) changes in corticospinal excitability post-HST may be modulated “downstream” of the primary motor cortex (M1). PMID:27990108

  14. The Time-Course of Acute Changes in Corticospinal Excitability, Intra-Cortical Inhibition and Facilitation Following a Single-Session Heavy Strength Training of the Biceps Brachii.

    PubMed

    Latella, Christopher; Hendy, Ashlee M; Pearce, Alan J; VanderWesthuizen, Dan; Teo, Wei-Peng

    2016-01-01

    Objective: The current understanding of acute neurophysiological responses to resistance training remains unclear. Therefore, we aimed to compare the time-course of acute corticospinal responses following a single-session heavy strength training (HST) of the biceps brachii (BB) muscle and provide quantifiable evidence based on the super-compensation model in an applied setting. Methods: Fourteen participants completed a counter-balanced, cross-over study that consisted of a single HST session (5 sets × 3 repetition maximum [RM]) of the BB and a control session (CON). Single- and paired-pulse transcranial magnetic stimulation (TMS) was used to measure changes in motor-evoked potential (MEP) amplitude, intra-cortical facilitation (ICF), short-interval intra-cortical inhibition (SICI) and long-interval intra-cortical inhibition (LICI). Additionally, maximal muscle compound wave (MMAX) and maximal voluntary isometric contraction (MVIC) of the BB were taken. All measures were taken at baseline, immediately post and at 10, 20, 30 min and 1, 2, 6, 24, 48 and 72 h post-training. Results: A significant reduction in MEP amplitude was observed immediately post training (P = 0.001), while MVIC (P < 0.001) and MMAX (P = 0.047) were reduced for up to 30 min post-training. An increase in MVIC (p < 0.001) and MMAX (p = 0.047) was observed at 6 h, while an increase in MEP amplitude (p = 0.014) was only observed at 48 and 72 h. No changes in SICI, ICF and LICI were observed. Conclusion: Our results suggest that: (1) acute changes in corticospinal measures returned to baseline in a shorter timeframe than the current super-compensation model (24-48 h) and (2) changes in corticospinal excitability post-HST may be modulated "downstream" of the primary motor cortex (M1).

  15. Pediatric sleep pharmacology.

    PubMed

    Pelayo, Rafael; Yuen, Kin

    2012-10-01

    This article reviews common sleep disorders in children and pharmacologic options for them. Discussions of pediatric sleep pharmacology typically focus on treatment of insomnia. Although insomnia is a major concern in this population, other conditions of concern in children are presented, such as narcolepsy, parasomnias, restless legs syndrome, and sleep apnea.

  16. Pharmacology for the Psychotherapist.

    ERIC Educational Resources Information Center

    Goldenberg, Myron Michael

    This book covers those areas of pharmacology that are of importance and interest to the psychotherapist. The 1st chapter introduces the various types of drugs. The 2nd chapter presents an overview of pharmacology and its principles. The 3rd chapter reviews aspects of the human body of importance to understanding the workings of psychotropic drugs.…

  17. Pharmacology Information System Ready

    ERIC Educational Resources Information Center

    Chemical and Engineering News, 1973

    1973-01-01

    Discusses the development and future of Prophet,'' a specialized information handling system for pharmacology research. It is designed to facilitate the acquisition and dissemination of knowledge about mechanisms of drug action, and it is hoped that it will aid in converting pharmacology research from an empirical to a predictive science. (JR)

  18. Curriculum Guidelines for Pharmacology.

    ERIC Educational Resources Information Center

    Shaw, David H.; And Others

    1990-01-01

    Pharmacology embraces the physical and chemical properties of drugs; the preparation of pharmaceutical agents; the absorption, fate, and excretion of drugs; and the effects of drugs on living systems. These guidelines represent a consensus on what would constitute a minimally acceptable pharmacology course for predoctoral dental students. (MLW)

  19. Nurse Practitioner Pharmacology Education.

    ERIC Educational Resources Information Center

    Waigandt, Alex; Chang, Jane

    A study compared the pharmacology training of nurse practitioner programs with medical and dental programs. Seventy-three schools in 14 states (40 nurse practitioner programs, 19 schools of medicine, and 14 schools of dentistry) were surveyed by mailed questionnaire about the number of hours devoted to the study of pharmacology. The major findings…

  20. Transient impairment of hippocampus-dependent learning and memory in relatively low-dose of acute radiation syndrome is associated with inhibition of hippocampal neurogenesis.

    PubMed

    Kim, Joong-Sun; Lee, Hae-June; Kim, Jong Choon; Kang, Seong Soo; Bae, Chun-Sik; Shin, Taekyun; Jin, Jae-Kwang; Kim, Sung Ho; Wang, Hongbing; Moon, Changjong

    2008-09-01

    Neurogenesis in the adult hippocampus, which occurs constitutively, is vulnerable to ionizing radiation. In the relatively low-dose exposure of acute radiation syndrome (ARS), the change in the adult hippocampal function is poorly understood. This study analyzed the changes in apoptotic cell death and neurogenesis in the DGs of hippocampi from adult ICR mice with single whole-body gamma-irradiation using the TUNEL method and immunohistochemical markers of neurogenesis, Ki-67 and doublecortin (DCX). In addition, the hippocampus-dependent learning and memory tasks after single whole-body gamma-irradiation were examined in order to evaluate the hippocampus-related behavioral dysfunction in the relatively low-dose exposure of ARS. The number of TUNEL-positive apoptotic nuclei in the dentate gyrus (DG) was increased 6-12 h after acute gamma-irradiation (a single dose of 0.5 to 4 Gy). In contrast, the number of Ki-67- and DCX-positive cells began to decrease significantly 6 h postirradiation, reaching its lowest level 24 h after irradiation. The level of Ki-67 and DCX immunoreactivity decreased in a dose-dependent manner within the range of irradiation applied (0-4 Gy). In passive avoidance and object recognition memory test, the mice trained 1 day after acute irradiation (2 Gy) showed significant memory deficits, compared with the sham controls. In conclusion, the pattern of the hippocampus-dependent memory dysfunction is consistent with the change in neurogenesis after acute irradiation. It is suggested that a relatively low dose of ARS in adult ICR mice is sufficiently detrimental to interrupt the functioning of the hippocampus, including learning and memory, possibly through the inhibition of neurogenesis.

  1. Integrating pharmacology and clinical pharmacology in universities.

    PubMed

    Buckingham, Julia C

    2012-06-01

    Continuing development of safe and effective new medicines is critically important for global health, social prosperity and the economy. The drug discovery-development pipeline depends critically on close partnerships between scientists and clinicians and on educational programmes that ensure that the pharmacological workforce, in its broadest sense, is fit for purpose. Here I consider factors that have influenced the development of basic and clinical pharmacology in UK universities over the past 40 years and discuss ways in which basic pharmacologists, clinical pharmacologists and scientists from different disciplines can work together effectively, while retaining their professional identities and fostering developments in their disciplines. Specifically, I propose the establishment of Institutes of Drug Discovery and Development, whose activities could include development and implementation of a translational pharmacology research strategy, drawing on the collective expertise of the membership and the university as whole; provision of a forum for regular seminars and symposia to promote the discipline, encourage collaboration and develop a cohesive community; provision of a research advisory service, covering, for example, data management, applications for ethics permission, clinical trials design, statistics and regulatory affairs; liaison with potential funders and leadership of major funding bids, including funding for doctoral training; provision of advice on intellectual property protection and the commercialization of research; liaison with corporate partners to facilitate collaboration, knowledge transfer and effective translation; and leadership of undergraduate and postgraduate education in basic and clinical pharmacology and related sciences for medical and science students, including continuing professional development and transferable skills.

  2. Knockdown of p54nrb inhibits migration, invasion and TNF-α release of human acute monocytic leukemia THP1 cells.

    PubMed

    Zhang, Xiujuan; Wu, Changli; Xiong, Wei; Chen, Chunling; Li, Rong; Zhou, Guangji

    2016-06-01

    54 kDa nuclear RNA- and DNA-binding protein (p54nrb) which is also called non-POU domain-containing octamer-binding protein (NONO) is known to be multifunctional involved in many nuclear processes. It was shown that p54nrb/NONO was closely related to the occurrence of erythroleukemia. Whether p54nrb/NONO plays a role in progress of human acute monocytic leukemia remains unknown. In the present study, we examined the effects of p54nrb/NONO silencing on the biological characteristics of human acute monocytic leukemia THP1 cells. The results showed that p54nrb was strongly expressed in THP1 cells, and knockdown of p54nrb slightly promoted proliferation and strongly inhibited motility and invasion of THP1 cells. Moreover, knockdown of p54nrb strongly decreased the release of TNF-α from THP1 cells by inhibiting certain process of TNF-α secretion, specially for the release of TNF-α induced by lipopolysaccharide (LPS). Notably, the infection of negative control shRNA-containing lentiviruses promoted the migration and the release of TNF-α induced by LPS in THP1 cells. All the above results demonstrated that p54nrb slightly inhibited THP1 cell proliferation, but significantly promoted migration, invasion and release of TNF-α induced by LPS in THP1 cells. The present study indicates that p54nrb is a powerful molecule involved in the regulation of cell motility and promotes the migration and invasion of THP1 cells, and it is more likely to be involved in the release of inflammatory mediators and the motility of inflammatory cells.

  3. AMIGO3 is an NgR1/p75 co-receptor signalling axon growth inhibition in the acute phase of adult central nervous system injury.

    PubMed

    Ahmed, Zubair; Douglas, Michael R; John, Gabrielle; Berry, Martin; Logan, Ann

    2013-01-01

    Axon regeneration in the injured adult CNS is reportedly inhibited by myelin-derived inhibitory molecules, after binding to a receptor complex comprised of the Nogo-66 receptor (NgR1) and two transmembrane co-receptors p75/TROY and LINGO-1. However, the post-injury expression pattern for LINGO-1 is inconsistent with its proposed function. We demonstrated that AMIGO3 levels were significantly higher acutely than those of LINGO-1 in dorsal column lesions and reduced in models of dorsal root ganglion neuron (DRGN) axon regeneration. Similarly, AMIGO3 levels were raised in the retina immediately after optic nerve crush, whilst levels were suppressed in regenerating optic nerves, induced by intravitreal peripheral nerve implantation. AMIGO3 interacted functionally with NgR1-p75/TROY in non-neuronal cells and in brain lysates, mediating RhoA activation in response to CNS myelin. Knockdown of AMIGO3 in myelin-inhibited adult primary DRG and retinal cultures promoted disinhibited neurite growth when cells were stimulated with appropriate neurotrophic factors. These findings demonstrate that AMIGO3 substitutes for LINGO-1 in the NgR1-p75/TROY inhibitory signalling complex and suggests that the NgR1-p75/TROY-AMIGO3 receptor complex mediates myelin-induced inhibition of axon growth acutely in the CNS. Thus, antagonizing AMIGO3 rather than LINGO-1 immediately after CNS injury is likely to be a more effective therapeutic strategy for promoting CNS axon regeneration when combined with neurotrophic factor administration.

  4. Enhanced recovery of breathing capacity from combined adenosine 2A receptor inhibition and daily acute intermittent hypoxia after chronic cervical spinal injury

    PubMed Central

    Navarrete-Opazo, A.; Dougherty, B.J.; Mitchell, G.S.

    2016-01-01

    Daily acute intermittent hypoxia (dAIH) improves breathing capacity after C2 spinal hemisection (C2HS) in rats. Since C2HS disrupts spinal serotonergic innervation below the injury, adenosine-dependent mechanisms underlie dAIH-induced functional recovery 2 weeks post-injury. We hypothesized that dAIH-induced functional recovery converts from an adenosine-dependent to a serotonin-dependent, adenosine-constrained mechanism with chronic injury. Eight weeks post-C2HS, rats began dAIH (10, 5-min episodes, 10.5% O2; 5-min intervals; 7 days) followed by AIH 3× per week (3×wAIH) for 8 additional weeks