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1.
Mult Scler ; 25(4): 601-609, 2019 04.
Artigo em Inglês | MEDLINE | ID: mdl-29368539

RESUMO

BACKGROUND: Walking impairment causes disability and reduced quality of life in patients with multiple sclerosis (MS). OBJECTIVE: Characterize the safety and efficacy of ADS-5102 (amantadine) extended release capsules, 274 mg administered once daily at bedtime in patients with MS with walking impairment. METHODS: This randomized, double-blind, placebo-controlled, 4-week study was conducted at 14 trial sites in the United States. Study objectives included safety and tolerability of ADS-5102, and efficacy assessments (Timed 25-Foot Walk (T25FW), Timed Up and Go (TUG), 2-Minute Walk Test, and Multiple Sclerosis Walking Scale-12). Fatigue, depression, and cognition also were assessed. RESULTS: A total of 60 patients were randomized (30 to ADS-5102 and 30 to placebo); 59 of whom were treated. The most frequent adverse events (AEs) were dry mouth, constipation, and insomnia. Five ADS-5102 patients and no placebo patients discontinued treatment due to AEs. One patient in the ADS-5102 group experienced a serious AE-suspected serotonin syndrome. A 16.6% placebo-adjusted improvement was seen in the T25FW test ( p < 0.05). A 10% placebo-adjusted improvement in TUG was also observed. No changes in fatigue, depression, or cognition were observed. CONCLUSION: ADS-5102 was generally well tolerated. These data demonstrate an effect of ADS-5102 on walking speed. Further studies are warranted to confirm these observations.


Assuntos
Amantadina/farmacologia , Dopaminérgicos/farmacologia , Discinesias/tratamento farmacológico , Esclerose Múltipla/tratamento farmacológico , Avaliação de Resultados em Cuidados de Saúde , Caminhada , Adulto , Idoso , Amantadina/administração & dosagem , Amantadina/efeitos adversos , Preparações de Ação Retardada , Dopaminérgicos/administração & dosagem , Dopaminérgicos/efeitos adversos , Método Duplo-Cego , Discinesias/etiologia , Discinesias/fisiopatologia , Teste de Esforço , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Esclerose Múltipla/complicações , Esclerose Múltipla/fisiopatologia , Estudo de Prova de Conceito
2.
Bull Exp Biol Med ; 166(6): 739-743, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31020587

RESUMO

Activities of noncompetitive NMDA receptor antagonists (aminoadamantane derivatives) were assessed in random-bred rats with modeled morphine withdrawal syndrome. A single intraperitoneal injection of hemantane (10 or 20 mg/kg) significantly and dose-dependently moderated some behavioral symptoms (teeth-chattering, ptosis, and vocalization) and reduced total score of morphine withdrawal syndrome. In morphine-abstinent rats, hemantane partially prevented the decrease in the thresholds of tactile sensitivity, but had no effect on locomotor activity and body weight loss. Under conditions of morphine withdrawal, intraperitoneal injection of amantadine (10 or 20 mg/kg) decreased motor activity and promoted body weight loss in parallel with the development of mechanical allodynia, but had no effect on the total withdrawal score. Comparison of aminoadamantane derivatives by behavioral and physiological parameters demonstrated the advantage of hemantane during morphine abstinence indicating the need of its study as a promising anti-addiction remedy.


Assuntos
Adamantano/análogos & derivados , Amantadina/farmacologia , Dependência de Morfina/fisiopatologia , Antagonistas de Entorpecentes/farmacologia , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Síndrome de Abstinência a Substâncias/tratamento farmacológico , Adamantano/farmacologia , Animais , Expressão Gênica , Hiperalgesia/induzido quimicamente , Hiperalgesia/fisiopatologia , Injeções Intraperitoneais , Masculino , Morfina/administração & dosagem , Dependência de Morfina/genética , Dependência de Morfina/metabolismo , Atividade Motora/efeitos dos fármacos , Ratos , Receptores de N-Metil-D-Aspartato/genética , Receptores de N-Metil-D-Aspartato/metabolismo , Síndrome de Abstinência a Substâncias/genética , Síndrome de Abstinência a Substâncias/metabolismo , Síndrome de Abstinência a Substâncias/fisiopatologia , Redução de Peso/efeitos dos fármacos
3.
Biochim Biophys Acta ; 1838(1 Pt B): 355-63, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24140008

RESUMO

Beta-propiolactone (BPL) is commonly used as an inactivating reagent to produce viral vaccines. Although BPL has been described to chemically modify nucleic acids, its effect on viral proteins, potentially affecting viral infectivity, remains poorly studied. Here, a H3N2 strain of influenza virus was submitted to treatment with various BPL concentrations (2-1000µM). Cell infectivity was progressively reduced and entirely abolished at 1mM BPL. Virus fusion with endosome being a critical step in virus infection, we analyzed its ability to fuse with lipid membrane after BPL treatment. By monitoring calcein leakage from liposomes fusing with the virus, we measured a decrease of membrane fusion in a BPL dose-dependent manner that correlates with the loss of infectivity. These data were complemented with cryo transmission electron microscopy (cryoTEM) and cryo electron tomography (cryoET) studies of native and modified viruses. In addition, a decrease of leakage irrespective of BPL concentration was measured suggesting that the insertion of HA2 fusion peptide into the target membrane was inhibited even at low BPL concentrations. Interestingly, mass spectrometry revealed that HA2 and M1 matrix proteins had been modified. Furthermore, fusion activity was partially restored by the protonophore monensin as confirmed by cryoTEM and cryoET. Moreover, exposure to amantadine, an inhibitor of M2 channel, did not alter membrane fusion activity of 1mM BPL treated virus. Taken together these results show that BPL treatment inhibits membrane fusion, likely by altering function of proteins involved in the fusion process, shedding new light on the effect of BPL on influenza virus.


Assuntos
Hemaglutininas Virais/química , Vírus da Influenza A Subtipo H3N2/química , Lipossomos/química , Propiolactona/química , Proteínas da Matriz Viral/química , Amantadina/química , Amantadina/farmacologia , Sequência de Aminoácidos , Microscopia Crioeletrônica , Relação Dose-Resposta a Droga , Fluoresceínas/química , Dados de Sequência Molecular , Monensin/química , Monensin/farmacologia , Permeabilidade , Propiolactona/farmacologia , Proteínas da Matriz Viral/antagonistas & inibidores , Internalização do Vírus/efeitos dos fármacos
4.
Chemistry ; 20(47): 15320-4, 2014 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-25319197

RESUMO

A simple strategy for designing salt-based supramolecular gelators comprised of various nonsteroidal anti-inflammatory drugs (NSAIDs) and amantadine (AMN) (an antiviral drug) has been demonstrated using a supramolecular synthon approach. Single-crystal and powder X-ray diffraction established the existence of the well-studied gel-forming 1D supramolecular synthon, namely, primary ammonium monocarboxylate (PAM) synthon in all the salts. Remarkably five out of six salts were found to be capable of gelling methyl salicylate (MS)-an important ingredient in commercially available topical gels; one such selected biocompatible salt displayed an anti-inflammatory response in prostaglandin E2 (PGE2 ) assay, thereby indicating their plausible biomedical applications.


Assuntos
Anti-Inflamatórios não Esteroides/química , Géis/química , Amantadina/química , Amantadina/farmacologia , Animais , Anti-Inflamatórios não Esteroides/farmacologia , Materiais Biocompatíveis/química , Linhagem Celular , Diclofenaco/química , Diclofenaco/farmacologia , Dinoprostona/metabolismo , Interferon gama/farmacologia , Lipopolissacarídeos/toxicidade , Macrófagos/citologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Reologia , Salicilatos/química , Sais/química
5.
J Liposome Res ; 24(3): 182-90, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-24443972

RESUMO

Liposomes have been used to diagnose and treat cancer and, to a lesser extent, cardiovascular disease. We previously showed the uptake of anionic liposomes into the atheromas of Watanabe heritable hyperlipidemic rabbits within lipid pools. However, the cellular distribution of anionic liposomes in atherosclerotic plaque remains undescribed. In addition, how anionic liposomes are absorbed into atherosclerotic plaque is unclear. We investigated the uptake and distribution of anionic liposomes in atherosclerotic plaque in aortic tissues from apolipoprotein E-deficient (ApoE(-/-)) mice. To facilitate the tracking of liposomes, we used liposomes containing fluorescently labeled non-silencing small interfering RNA. Confocal microscopy analysis showed the uptake of anionic liposomes into atherosclerotic plaque and colocalization with macrophages. Transmission electron microscopy analysis revealed anionic liposomal accumulation in macrophages. To investigate how anionic liposomes cross the local endothelial barrier, we examined the role of clathrin-mediated endocytosis in human coronary artery endothelial cells (HCAECs) treated with or without the inflammatory cytokine tumor necrosis factor (TNF)-α. Pretreatment with amantadine, an inhibitor of clathrin-mediated endocytosis, significantly decreased liposomal uptake in HCAECs treated with or without TNF-α by 77% and 46%, respectively. Immunoblot analysis showed that endogenous clathrin expression was significantly increased in HCAECs stimulated with TNF-α but was inhibited by amantadine. These studies indicated that clathrin-mediated endocytosis is partly responsible for the uptake of liposomes by endothelial cells. Our results suggest that anionic liposomes target macrophage-rich areas of vulnerable plaque in ApoE(-)(/)(-) mice; this finding may lead to the development of novel diagnostic and therapeutic strategies for treating vulnerable plaque in humans.


Assuntos
Lipossomos/metabolismo , Placa Aterosclerótica/fisiopatologia , Amantadina/farmacologia , Animais , Ânions/administração & dosagem , Aorta/patologia , Apolipoproteínas E/deficiência , Clatrina/biossíntese , Clatrina/fisiologia , Endocitose/efeitos dos fármacos , Endotélio Vascular , Humanos , Lipossomos/administração & dosagem , Macrófagos/metabolismo , Camundongos , Fator de Necrose Tumoral alfa/metabolismo
6.
Biochim Biophys Acta ; 1808(1): 415-23, 2011 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20883664

RESUMO

Membrane proteins change their conformations to respond to environmental cues, thus conformational plasticity is important for function. The influenza A M2 protein forms an acid-activated proton channel important for the virus lifecycle. Here we have used solid-state NMR spectroscopy to examine the conformational plasticity of membrane-bound transmembrane domain of M2 (M2TM). (13)C and (15)N chemical shifts indicate coupled conformational changes of several pore-facing residues due to changes in bilayer thickness, drug binding, and pH. The structural changes are attributed to the formation of a well-defined helical kink at G34 in the drug-bound state and in thick lipid bilayers, nonideal backbone conformation of the secondary-gate residue V27 in the presence of drug, and nonideal conformation of the proton-sensing residue H37 at high pH. The chemical shifts constrained the (ϕ, ψ) torsion angles for three "basis" states, the equilibrium among which explains the multiple resonances per site in the NMR spectra under different combinations of bilayer thickness, drug binding, and pH conditions. Thus, conformational plasticity is important for the proton conduction and inhibition of M2TM. The study illustrates the utility of NMR chemical shifts for probing the structural plasticity and folding of membrane proteins.


Assuntos
Química Farmacêutica/métodos , Vírus da Influenza A/metabolismo , Membranas Artificiais , Proteínas da Matriz Viral/metabolismo , Amantadina/farmacologia , Antivirais/farmacologia , Detergentes/química , Humanos , Concentração de Íons de Hidrogênio , Bicamadas Lipídicas/química , Lipídeos/química , Espectroscopia de Ressonância Magnética/métodos , Ligação Proteica , Conformação Proteica , Estrutura Terciária de Proteína
7.
Biochim Biophys Acta ; 1808(2): 516-21, 2011 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-20969830

RESUMO

Amantadine-sensitive proton uptake by liposomes is currently the preferred method of demonstrating M2 functionality after reconstitution, to validate structural determination with techniques such as solid-state NMR. With strong driving forces (two decades each of both [K(+)] gradient-induced membrane potential and [H(+)] gradient), M2(22-62) showed a transport rate of 78 H(+)/tetramer-s (pH(o) 6.0, pH(i) 8.0, nominal V(m)=-114 mV), higher than previously measured for similar, shorter, and full-length constructs. Amantadine sensitivity of the conductance domain at pH 6.8 was also comparable to other published reports. Proton flux rate was optimal at protein densities of 0.05-1.0% (peptide wt.% in lipid). Rundown of total proton uptake after addition of valinomycin and CCCP, as detected by delayed addition of valinomycin, indicated M2-induced K(+) flux of 0.1K(+)/tetramer-s, and also demonstrated that the K(+) permeability, relative to H(+), was 2.8 × 10(-6). Transport rate, amantadine and cyclooctylamine sensitivity, acid activation, and H(+) selectivity were all consistent with full functionality of the reconstituted conductance domain. Decreased external pH increased proton uptake with an apparent pK(a) of 6.


Assuntos
Vírus da Influenza A/química , Canais Iônicos/química , Proteínas da Matriz Viral/química , Amantadina/farmacologia , Carbonil Cianeto m-Clorofenil Hidrazona/farmacologia , Concentração de Íons de Hidrogênio , Vírus da Influenza A/genética , Vírus da Influenza A/metabolismo , Canais Iônicos/genética , Canais Iônicos/metabolismo , Cinética , Lipossomos , Potenciais da Membrana , Fragmentos de Peptídeos/química , Fragmentos de Peptídeos/genética , Fragmentos de Peptídeos/metabolismo , Proteínas Recombinantes/química , Proteínas Recombinantes/genética , Proteínas Recombinantes/metabolismo , Valinomicina/farmacologia , Proteínas da Matriz Viral/genética , Proteínas da Matriz Viral/metabolismo
8.
Biomacromolecules ; 13(1): 231-8, 2012 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-22136386

RESUMO

Nonviral gene therapy focuses intensely on nitrogen-containing macromolecules and lipids to condense and deliver DNA as a therapeutic for genetic human diseases. For the first time, DNA binding and gene transfection experiments compared phosphonium-containing macromolecules with their respective ammonium analogs. Conventional free radical polymerization of quaternized 4-vinylbenzyl chloride monomers afforded phosphonium- and ammonium-containing homopolymers for gene transfection experiments of HeLa cells. Aqueous size exclusion chromatography confirmed similar absolute molecular weights for all polyelectrolytes. DNA gel shift assays and luciferase expression assays revealed phosphonium-containing polymers bound DNA at lower charge ratios and displayed improved luciferase expression relative to the ammonium analogs. The triethyl-based vectors for both cations failed to transfect HeLa cells, whereas tributyl-based vectors successfully transfected HeLa cells similar to Superfect demonstrating the influence of the alkyl substituent lengths on the efficacy of the gene delivery vehicle. Cellular uptake of Cy5-labeled DNA highlighted successful cellular uptake of triethyl-based polyplexes, showing that intracellular mechanisms presumably prevented luciferase expression. Endocytic inhibition studies using genistein, methyl ß-cyclodextrin, or amantadine demonstrated the caveolae-mediated pathway as the preferred cellular uptake mechanism for the delivery vehicles examined. Our studies demonstrated that changing the polymeric cation from ammonium to phosphonium enables an unexplored array of synthetic vectors for enhanced DNA binding and transfection that may transform the field of nonviral gene delivery.


Assuntos
DNA , Terapia Genética/métodos , Vetores Genéticos , Compostos Organofosforados/química , Polímeros , Amantadina/farmacologia , Anticarcinógenos/farmacologia , Cavéolas/química , Cavéolas/metabolismo , DNA/química , DNA/farmacologia , Dopaminérgicos/farmacologia , Endocitose/efeitos dos fármacos , Vetores Genéticos/química , Vetores Genéticos/farmacologia , Genisteína/farmacologia , Células HeLa , Humanos , Polímeros/química , Polímeros/farmacologia , beta-Ciclodextrinas/farmacologia
9.
J Am Chem Soc ; 133(30): 11572-9, 2011 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-21661724

RESUMO

The influenza A M2 protein forms a proton channel for virus infection and also mediates virus assembly and budding. The minimum protein length that encodes both functions contains the transmembrane (TM) domain (roughly residues 22-46) for the amantadine-sensitive proton-channel activity and an amphipathic cytoplasmic helix (roughly residues 45-62) for curvature induction and virus budding. However, structural studies involving the TM domain with or without the amphipathic helix differed on the drug-binding site. Here we use solid-state NMR spectroscopy to determine the amantadine binding site in the cytoplasmic-helix-containing M2(21-61). (13)C-(2)H distance measurements of (13)C-labeled protein and (2)H-labeled amantadine showed that in 1,2-dimyristoyl-sn-glycero-3-phosphocholine (DMPC) bilayers, the first equivalent of drug bound S31 inside the M2(21-61) pore, similar to the behavior of M2 transmembrane peptide (M2TM) in DMPC bilayers. The nonspecific surface site of D44 observed in M2TM is disfavored in the longer peptide. Thus, the pharmacologically relevant drug-binding site in the fully functional M2(21-61) is S31 in the TM pore. Interestingly, when M2(21-61) was reconstituted into a virus-mimetic membrane containing 30% cholesterol, no chemical shift perturbation was observed for pore-lining residues, whereas M2TM in the same membrane exhibited drug-induced chemical shift changes. Reduction of the cholesterol level and the use of unsaturated phospholipids shifted the conformational equilibrium of M2TM fully to the bound state but did not rescue drug binding to M2(21-61). These results suggest that the amphipathic helix, together with cholesterol, modulates the ability of the TM helix to bind amantadine. Thus, the M2 protein interacts with the lipid membrane and small-molecule inhibitors in a complex fashion, and a careful examination of the environmental dependence of the protein conformation is required to fully understand the structure-function relation of this protein.


Assuntos
Amantadina/química , Antivirais/química , Citoplasma/química , Membranas Artificiais , Proteínas da Matriz Viral/química , Amantadina/farmacologia , Antivirais/farmacologia , Sítios de Ligação/efeitos dos fármacos , Citoplasma/efeitos dos fármacos , Espectroscopia de Ressonância Magnética , Modelos Moleculares , Relação Estrutura-Atividade
10.
Antiviral Res ; 76(1): 48-58, 2007 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-17574688

RESUMO

Chemotherapy for patients chronically infected with hepatitis C virus (HCV) is ineffective in over 50% of cases, generating a high demand for new drug targets. The p7 protein of HCV displays membrane channel activity in vitro and is essential for replication in vivo though its precise role in the virus life cycle is unknown. p7 channel activity can be specifically inhibited by several classes of compounds, making this protein an attractive candidate for drug development, though techniques used to date in characterising this protein are unsuited to compound library screening. Here we describe an assay for the channel forming ability of p7 based on the release of a fluorescent indicator from liposomes. We show that recombinant p7 from genotype 1b HCV causes a dose-dependent release of dye when mixed with liposomes and that this property is enhanced at acidic pH. We demonstrate that this activity is due to the formation of a size-selective pore rather than non-specific disruption of liposomes and that activity can be blocked by amantadine and several other compounds, validating it as a measure of p7 channel function. This system provides the first convenient in vitro assay for exploiting p7 as a therapeutic target.


Assuntos
Antivirais/farmacologia , Hepacivirus/química , Canais Iônicos/metabolismo , Lipossomos/metabolismo , Testes de Sensibilidade Microbiana/métodos , Proteínas Virais/antagonistas & inibidores , Proteínas Virais/metabolismo , Ácidos , Amantadina/farmacologia , Fluoresceínas/metabolismo , Permeabilidade , Porinas/biossíntese , Proteínas Recombinantes/antagonistas & inibidores , Proteínas Recombinantes/metabolismo , Proteínas Virais/efeitos dos fármacos
11.
Antivir Ther ; 11(4): 507-19, 2006.
Artigo em Inglês | MEDLINE | ID: mdl-16856625

RESUMO

BACKGROUND: Formation of transmembrane ion channels by hepatitis C virus (HCV) p7 and abrogation of channel function by amantadine was demonstrated in vitro. The relevance of HCV p7 amino acid (aa) variations for response to antiviral therapy with amantadine is unknown. METHODS: HCV p7 was sequenced in 86 individuals who were infected with HCV genotype 1. Thirty-six of 86 patients received amantadine within an interferon-alpha (IFN-alpha)-based antiviral therapy. Helical wheel modelling for HCV p7 was performed. RESULTS: No significant correlation of overall aa variations within HCV p7 was observed with response to IFN-alpha-based therapy with amantadine in HCV genotype 1alpha/b infected patients. When analysis was restricted to non-conservative aa variations, a higher number of aa substitutions within complete HCV p7 and transmembrane helix 2 was associated with non-response in HCV-1b-infected patients receiving therapy with amantadine (P=0.015 and P=0.037, respectively), without amantadine (P=0.106 and P=0.118, respectively), and in the total cohort of HCV-1b-infected patients (P=0.00007 and P=0.011, respectively). Furthermore, substitution L20F was observed more often in non-responders than responders with HCV-1b infection and therapy with amantadine (P=0.099). By in silico modelling, aa 20 was located toward the p7 channel lumen. Substitution L20F may impair amantadine action by altering the shape of the ion channel pore. CONCLUSION: Substitution L20F within HCV p7 may be associated with non-response to combination therapy specifically with amantadine in HCV-1b-infected patients. Non-responders with HCV-1b infection showed higher numbers of non-conservative aa variations within HCV p7 than responders, irrespective of the application of amantadine.


Assuntos
Amantadina/uso terapêutico , Sequência de Aminoácidos , Antivirais/uso terapêutico , Variação Genética , Hepatite C Crônica/tratamento farmacológico , Interferon-alfa/uso terapêutico , Polietilenoglicóis/uso terapêutico , Proteínas Virais/genética , Amantadina/farmacologia , Antivirais/farmacologia , Quimioterapia Combinada , Hepatite C Crônica/virologia , Humanos , Interferon-alfa/farmacologia , Dados de Sequência Molecular , Polietilenoglicóis/farmacologia , Análise de Sequência de DNA , Resultado do Tratamento , Proteínas Virais/química
12.
Biochim Biophys Acta ; 467(3): 273-9, 1977 Jun 16.
Artigo em Inglês | MEDLINE | ID: mdl-884071

RESUMO

The ability of eleven amantadine derivatives to induce phase separation in dipalmitoyl phosphatidylcholine bilayers was studied by differential scanning calorimetry. The relative potency varied with the shape and size of the hydrocarbon cage. These agents also markedly inhibited blood platelet aggregation. The relative potencies of these compounds to induce phase separation showed a significant correlation (r = 0.70) with their platelet inhibitory activity suggesting that their pharmacologic action may be at the level of the platelet membrane. The effective concentration of the parent component amantadine is similar to its pharmacologic concentration suggesting its use as an anti-platelet drug.


Assuntos
Amantadina/farmacologia , Membranas Artificiais , Fosfatidilcolinas , Agregação Plaquetária/efeitos dos fármacos , Amantadina/análogos & derivados , Humanos , Cinética , Modelos Biológicos
13.
Biochim Biophys Acta ; 926(3): 205-14, 1987 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-3318934

RESUMO

The vacuoles of logarithmic and stationary stage cells were compared by 31P-NMR with regard to pH, orthophosphate (Pi) content and average size of polyphosphate. The vacuoles of stationary cells had lower pH, higher Pi content, and polyphosphates of longer average chain length, although total polyphosphate content was about the same as in logarithmic cells. The lower vacuolar pH in stationary cells was the major cause of a larger cytoplasmic-vacuolar pH gradient. Addition of NH4Cl, (NH4)2SO4, methylamine or amantadine at pH 8 to cells in either stage caused an increase in both cytoplasmic and vacuolar pH, with little or no change in the cytoplasmic-vacuolar pH gradient. However, the administration of ammonium salts to the cells at pH 8.0 resulted in rapid hydrolysis of the intravacuolar polyphosphate to tripolyphosphate and Pi, with attendant redistribution of Pi between the vacuolar and cytoplasmic compartments.


Assuntos
Aminas/farmacologia , Fosfatos/metabolismo , Saccharomyces cerevisiae/crescimento & desenvolvimento , Amantadina/farmacologia , Cloreto de Amônio/farmacologia , Sulfato de Amônio/farmacologia , Citoplasma/metabolismo , Glucose/farmacologia , Concentração de Íons de Hidrogênio , Espectroscopia de Ressonância Magnética , Metilaminas/farmacologia , Oxigênio/farmacologia , Polímeros , Saccharomyces cerevisiae/citologia , Vacúolos/metabolismo
14.
PLoS One ; 10(5): e0125828, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25946195

RESUMO

Viroporins are a family of low-molecular-weight hydrophobic transmembrane proteins that are encoded by various animal viruses. Viroporins form transmembrane pores in host cells via oligomerization, thereby destroying cellular homeostasis and inducing cytopathy for virus replication and virion release. Among the Picornaviridae family of viruses, the 2B protein encoded by enteroviruses is well understood, whereas the viroporin activity of the 2B protein encoded by the foot-and-mouth disease virus (FMDV) has not yet been described. An analysis of the FMDV 2B protein domains by computer-aided programs conducted in this study revealed that this protein may contain two transmembrane regions. Further biochemical, biophysical and functional studies revealed that the protein possesses a number of features typical of a viroporin when it is overexpressed in bacterial and mammalian cells as well as in FMDV-infected cells. The protein was found to be mainly localized in the endoplasmic reticulum (ER), with both the N- and C-terminal domains stretched into the cytosol. It exhibited cytotoxicity in Escherichia coli, which attenuated 2B protein expression. The release of virions from cells infected with FMDV was inhibited by amantadine, a viroporin inhibitor. The 2B protein monomers interacted with each other to form both intracellular and extracellular oligomers. The Ca(2+) concentration in the cells increased, and the integrity of the cytoplasmic membrane was disrupted in cells that expressed the 2B protein. Moreover, the 2B protein induced intense autophagy in host cells. All of the results of this study demonstrate that the FMDV 2B protein has properties that are also found in other viroporins and may be involved in the infection mechanism of FMDV.


Assuntos
Autofagia/genética , Membrana Celular/metabolismo , Vírus da Febre Aftosa/metabolismo , Proteínas não Estruturais Virais/antagonistas & inibidores , Proteínas Virais Reguladoras e Acessórias/antagonistas & inibidores , Amantadina/farmacologia , Animais , Cálcio/metabolismo , Linhagem Celular , Permeabilidade da Membrana Celular , Cricetinae , Retículo Endoplasmático/virologia , Escherichia coli/virologia , Vírus da Febre Aftosa/genética , Humanos , Estrutura Terciária de Proteína , Liberação de Vírus/efeitos dos fármacos , Replicação Viral/fisiologia
15.
FEBS Lett ; 535(1-3): 34-8, 2003 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-12560074

RESUMO

Hepatitis C virus (HCV) cannot be grown in vitro, making biochemical identification of new drug targets especially important. HCV p7 is a small hydrophobic protein of unknown function, yet necessary for particle infectivity in related viruses [Harada, T. et al., (2000) J. Virol. 74, 9498-9506]. We show that p7 can be cross-linked in vivo as hexamers. Escherichia coli expressed p7 fusion proteins also form hexamers in vitro. These and HIS-tagged p7 function as calcium ion channels in black lipid membranes. This activity is abrogated by Amantadine, a compound that inhibits ion channels of influenza [Hay, A.J. et al. (1985) EMBO J. 4, 3021-3024; Duff, K.C. and Ashley, R.H. (1992) Virology 190, 485-489] and has recently been shown to be active in combination with current HCV therapies.


Assuntos
Amantadina/farmacologia , Antivirais/farmacologia , Canais Iônicos/efeitos dos fármacos , Proteínas Virais/química , Proteínas Virais/metabolismo , Carcinoma Hepatocelular/metabolismo , Humanos , Canais Iônicos/química , Canais Iônicos/metabolismo , Bicamadas Lipídicas/química , Membranas Artificiais , Microscopia Eletrônica , Proteínas Recombinantes de Fusão/biossíntese , Proteínas Recombinantes de Fusão/química , Células Tumorais Cultivadas , Proteínas Virais/ultraestrutura
16.
Int Immunopharmacol ; 1(1): 167-75, 2001 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11367514

RESUMO

1-Adamantylamide-L-alanyl-D-isoglutamine (adamantylamide dipeptide (AdDP)) belongs to a group of desmuramyl muramyl peptide derivatives which are able to protect an organism from some viral infections. Encapsulation of AdDP to egg phosphatidyl choline liposomes and the targeting of this drug to lymphatic node macrophages via subcutaneous (s.c.) administration proved to be the efficient way to protect mice against irradiation when administered s.c., 24 h prior to lethal gamma-irradiation (long-term survival rate in the range of 40% compared with 0% in saline or free drug control). Parameters characteristic for the recovery of haemopoiesis in the bone marrow (number of granulocyte-macrophage haemopoietic progenitor cells, granulocyte-macrophage colony forming cells (GM-CFC)) were significantly improved in comparison with the controls and free drug on day 10 after 6.5 Gy irradiation. The haemopoietic effect was observed in the broad application time window (72 h before and 48 h after irradiation). Very high radioprotective effect of s.c. administered liposomal AdDP (L-AdDP) can be explained (together with induction of haemopoiesis) by the effective and long-lasting activation of nonspecific immunity, which withholds the onset of septicemia in early days after irradiation. Induction of nonspecific immunity was proven in Candida albicans infectious model. L-AdDP significantly increased both the survival time and score (about 40% survival compared with 0% in controls and free drug). In conclusion, L-AdDP could be therapeutically beneficial to moderate the haemopoietic damage (undesirable effect of radiotherapy or chemotherapy) and induce the non-specific immunity to support the antimicrobial treatment of immunocompromised patients.


Assuntos
Adjuvantes Imunológicos/farmacologia , Amantadina/análogos & derivados , Amantadina/farmacologia , Dipeptídeos/farmacologia , Hematopoese/efeitos dos fármacos , Lesões Experimentais por Radiação/prevenção & controle , Adjuvantes Imunológicos/administração & dosagem , Amantadina/administração & dosagem , Animais , Ensaio de Unidades Formadoras de Colônias , Dipeptídeos/administração & dosagem , Feminino , Lipossomos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos C57BL
17.
Int Immunopharmacol ; 4(8): 1099-106, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15222985

RESUMO

In this study we tested the stimulatory effect of adamantylamide-l-alanyl-d-isoglutamine (AdDP) or its liposomal formulation (L-AdDP) on recovery of the granulocyte-macrophage hemopoietic progenitor cells in the bone marrow of sublethally irradiated mice of various ages. Number of GM-CFC progenitors in femur on day 10 was used as a parameter reflecting the stimulatory activity. Mice (aged 3-5 month) pre-treated with AdDP or L-AdDP via s.c. route displayed enhanced recovery of the granulocyte-macrophage hemopoietic progenitor cells at the dose of 5.5 Gy. Overaged mice (2 years) responded to the treatment when the dose was increased to 6.5 Gy, while radiation doses below 5.5 Gy should be used to see the stimulation effect in young mice (6 weeks). Entrapment of AdDP into liposomes enhanced costimulatory activity of sera of treated mice and prolongated this activity at least for 30 h after stimulation, in comparison to the mice treated with free AdDP where the costimulatory activity was spanned only up to 12 h. In conclusion, L-AdDP represents a suitable formulation of AdDP that induced recovery of GM-CFC progenitors in the femur of irradiated mice of various ages. The stimulatory effect depends on the extent of injury to bone marrow hemopoietic microenvironments caused by various doses of gamma-irradiation.


Assuntos
Amantadina/análogos & derivados , Amantadina/farmacologia , Dipeptídeos/farmacologia , Fator Estimulador de Colônias de Granulócitos e Macrófagos/metabolismo , Células-Tronco Hematopoéticas/efeitos dos fármacos , Lesões Experimentais por Radiação/prevenção & controle , Protetores contra Radiação/farmacologia , Envelhecimento , Amantadina/administração & dosagem , Animais , Células Cultivadas , Dipeptídeos/administração & dosagem , Relação Dose-Resposta à Radiação , Feminino , Fêmur/patologia , Hematopoese/efeitos dos fármacos , Células-Tronco Hematopoéticas/patologia , Células-Tronco Hematopoéticas/efeitos da radiação , Lipossomos , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos CBA , Lesões Experimentais por Radiação/patologia , Protetores contra Radiação/administração & dosagem
18.
Vopr Virusol ; 33(1): 22-6, 1988.
Artigo em Russo | MEDLINE | ID: mdl-3369145

RESUMO

The influence of adamantane derivatives (remantadine and amantadine) on the surface charge of lipid bilayer when they are adsorbed on an artificially formed bilayer lipid membrane (BLM) was studied. The presence of the final number of binding centres on the BLM surface for remantadine and amantadine molecules and the cooperative nature of interaction of these compounds with the lipid bilayer were demonstrated. The features of interaction of influenza virus proteins isolated from the virion--M protein and a mixture of surface glycoproteins--were studied. Both antiviral compounds were shown to reduce markedly M protein adsorption on the lipid bilayer and to affect negligibly the sorption properties of the surface glycoproteins. Remantadine molecules interact directly with M protein molecules reducing their hydrophobic properties and, thereby, reducing the affinity of this viral polypeptide to lipid bilayer.


Assuntos
Adamantano/análogos & derivados , Amantadina/farmacologia , Vírus da Influenza A/efeitos dos fármacos , Bicamadas Lipídicas/farmacologia , Membranas Artificiais , Rimantadina/farmacologia , Proteínas Virais/farmacologia , Adsorção , Interações Medicamentosas , Glicoproteínas de Membrana , Recombinação Genética , Propriedades de Superfície , Proteínas Virais de Fusão/isolamento & purificação , Proteínas Virais de Fusão/farmacologia , Proteínas da Matriz Viral/isolamento & purificação , Proteínas da Matriz Viral/farmacologia , Proteínas Virais/isolamento & purificação
19.
Eksp Klin Farmakol ; 58(4): 8-11, 1995.
Artigo em Russo | MEDLINE | ID: mdl-7580761

RESUMO

The effect of acute and chronic administration (50 mg/kg, p.o.) of a new immunostimulator, bromantan exhibiting psychostimulant features on the content of NE, DA and 5-HT, and their metabolites are studied. Bromantan induced a significant increase in the 5-HT and 5-HIAA content in the frontal cortex and delayed an increase in their content in subcortical brain regions. A stable decrease in the 5-HT and 5-HIAA levels in the cerebellum is observed. The drug also affected the DA parameters of the brain thus suggesting an important role of dopaminergic system in the mechanism of pharmacological effects of the drug.


Assuntos
Adjuvantes Imunológicos/farmacologia , Amantadina/análogos & derivados , Encéfalo/efeitos dos fármacos , Psicotrópicos/farmacologia , Receptores Dopaminérgicos/efeitos dos fármacos , Receptores de Serotonina/efeitos dos fármacos , Amantadina/farmacologia , Animais , Encéfalo/metabolismo , Química Encefálica/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Masculino , Polietilenoglicóis/farmacologia , Ratos , Ratos Wistar , Receptores Dopaminérgicos/análise , Receptores de Serotonina/análise , Solventes/farmacologia , Fatores de Tempo
20.
Colloids Surf B Biointerfaces ; 105: 31-6, 2013 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-23352945

RESUMO

This research is aimed to develop a nano-sized supramolecular micelle delivery system of cis-dichlorodiammine platinum (II) (CDDP) in order to achieve the passive tumor targeting. Firstly, star-shaped poly (γ-benzyl-L-glutamate) was synthesized by the ring-opening polymerization of γ-benzyl-L-glutamate-N-carboxyanhydride initiated with per-6-amino-ß-cyclodextrin. After removal of benzyl groups, ß-cyclodextrin based seven-armed poly (L-glutamic acid) (ß-CD-7PLGA) was obtained. ß-CD-7PLGA/CDDP complexes were prepared by the complex reaction between the carboxylic groups of ß-CD-7PLGA and CDDP. Further inclusion of ß-CD-7PLGA/CDDP complexes with adamantine terminated mPEG (mPEG-Ad) gave CDDP supramolecular micelles (mPEG-Ad@ß-CD-7PLGA/CDDP). The formation of mPEG-Ad@ß-CD-7PLGA/CDDP supramolecular micelles was confirmed by fluorescence spectrophotoscopy and particle size measurements. All the micelles showed spherical shape, and their sizes increased from 100 to 135 nm with the increase of PLGA arm molecular weight. mPEG-Ad@CD-7PLGA/CDDP micelles showed sustained drug release profiles over 50h in PBS. Compared with CDDP, mPEG-Ad@ß-CD-7PLGA/CDDP supramolecular micelles showed essential decreased cytotoxicity to KB cells, suggesting their great potential as the delivery carriers of CDDP.


Assuntos
Amantadina/farmacologia , Cisplatino/farmacologia , Sistemas de Liberação de Medicamentos , Células KB/efeitos dos fármacos , Polietilenoglicóis/química , Ácido Poliglutâmico/metabolismo , beta-Ciclodextrinas/química , Antineoplásicos/farmacologia , Dopaminérgicos/farmacologia , Humanos , Células KB/patologia , Micelas , Peso Molecular , Nanopartículas/administração & dosagem , Tamanho da Partícula , Polietilenoglicóis/metabolismo , Ácido Poliglutâmico/química , Espectrometria de Fluorescência , beta-Ciclodextrinas/metabolismo
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