RESUMEN
Macrophages (MΦ) infected with human immunodeficiency virus (HIV)-1 or activated by its envelope protein gp120 exert neurotoxicity. We found previously that signaling via p38 mitogen-activated protein kinase (p38 MAPK) is essential to the neurotoxicity of HIVgp120-stimulated MΦ. However, the associated downstream pathways remained elusive. Here we show that cysteinyl-leukotrienes (CysLT) released by HIV-infected or HIVgp120 stimulated MΦ downstream of p38 MAPK critically contribute to neurotoxicity. SiRNA-mediated or pharmacological inhibition of p38 MAPK deprives MΦ of CysLT synthase (LTC4S) and, pharmacological inhibition of the cysteinyl-leukotriene receptor 1 (CYSLTR1) protects cerebrocortical neurons against toxicity of both gp120-stimulated and HIV-infected MΦ. Components of the CysLT pathway are differentially regulated in brains of HIV-infected individuals and a transgenic mouse model of NeuroHIV (HIVgp120tg). Moreover, genetic ablation of LTC4S or CysLTR1 prevents neuronal damage and impairment of spatial memory in HIVgp120tg mice. Altogether, our findings suggest a novel critical role for cysteinyl-leukotrienes in HIV-associated brain injury.
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Cisteína , Infecciones por VIH , VIH-1 , Ratones , Humanos , Animales , VIH-1/metabolismo , Macrófagos/metabolismo , Leucotrienos/metabolismo , Neuronas/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Ratones Transgénicos , Infecciones por VIH/metabolismoRESUMEN
The neuropathogenesis of HIV associated neurocognitive disorders (HAND) involves disruption of mitochondrial homeostasis and increased neuroinflammation. However, it is unknown if alterations in mitochondrial biogenesis in the brain underlie the neuropathogenesis of HAND. In this study, neuropathological and molecular analyses of mitochondrial biogenesis and inflammatory pathways were performed in brain specimens from a well-characterized cohort of HIV+ cases that were on antiretroviral regimens. In vitro investigations using primary human astroglia and neurons were used to probe the underlying mechanisms of mitochondrial alterations. In frontal cortices from HAND brains compared to cognitive normal brains, total levels of transcription factors that regulate mitochondrial biogenesis, peroxisome proliferator-activated receptor γ coactivator 1-α (PGC-1α) and transcription factor A, mitochondrial (TFAM) were decreased. Immunohistochemical analyses revealed that TFAM was decreased in neurons and increased in astroglia. These changes were accompanied by decreased total mitochondrial DNA per cell and increased levels of messenger RNA for the proinflammatory cytokine interleukin (IL)-1ß. To determine how IL-1ß affects astroglial bioenergetic processes and mitochondrial activity, human astroglial cultures were exposed to recombinant IL-1ß. IL-1ß induced mitochondrial activity within 30â¯min of treatment, altered mitochondrial related gene expression, altered mitochondrial morphology, enhanced adenoside triphosphate (ATP) utilization and increased the expression of inflammatory cytokines. WIN55,212-2 (WIN), an aminoalkylindole derivative and cannabinoid receptor agonist, blocked IL-1ß-induced bioenergetic fluctuations and inflammatory gene expression in astroglia independent of cannabinoid receptor (CB)1 and peroxisome proliferator-activated receptor (PPAR) γ. A PPARα antagonist reversed the anti-inflammatory effects of WIN in human astroglia. These results show that mitochondrial biogenesis is differentially regulated in neurons and astroglia in HAND brains and that targeting astroglial bioenergetic processes may be a strategy to modulate neuroinflammation.
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Fármacos Anti-VIH/uso terapéutico , Astrocitos/metabolismo , Encéfalo/metabolismo , Seropositividad para VIH/metabolismo , Mitocondrias/metabolismo , Biogénesis de Organelos , Fármacos Anti-VIH/farmacología , Astrocitos/efectos de los fármacos , Astrocitos/patología , Encéfalo/efectos de los fármacos , Encéfalo/patología , Células Cultivadas , Proteínas de Unión al ADN/metabolismo , Seropositividad para VIH/tratamiento farmacológico , Seropositividad para VIH/patología , Humanos , Inflamación/metabolismo , Inflamación/patología , Interleucina-1beta/farmacología , Mitocondrias/efectos de los fármacos , Mitocondrias/patología , Proteínas Mitocondriales/metabolismo , Neuronas/efectos de los fármacos , Neuronas/metabolismo , Neuronas/patología , Coactivador 1-alfa del Receptor Activado por Proliferadores de Peroxisomas gamma/metabolismo , Factores de Transcripción/metabolismoRESUMEN
In this work, we present the synthesis of a novel Zn-Salphen complex containing an allyl group, which was used as building block in the further preparation of a new family of functional terpolymers. These polymers were obtained through radical co-polymerization with methyl metacrylate (MMA) and n-butyl acrylate (nBuA) in different ratios. The supramolecular recognition behavior of each polymer was evaluated via potentiometric measurements against selected anions in aqueous media. Interestingly, this proof of concept study shows that these systems were selective against only fluoride (F-) or both, fluoride and acetate (OAc-), by tailoring the relative content of Zn-Salphen monomer, thus making them a promising starting point for modular design of chemical sensors through straightforward synthetic approaches.
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Resinas Acrílicas/química , Fenilendiaminas/química , Polímeros/química , Zinc/química , Estructura Molecular , Polimerizacion , Polímeros/síntesis química , Polimetil Metacrilato/químicaRESUMEN
HIV-1 infection causes injury to the central nervous system (CNS) and is often associated with neurocognitive disorders. One model for brain damage seen in AIDS patients is the transgenic (tg) mouse expressing a soluble envelope protein gp120 of HIV-1 LAV in the brain in astrocytes under the control of the promoter of glial fibrillary acidic protein. These GFAP-gp120tg mice manifest several key neuropathological features observed in AIDS brains, such as decreased synaptic and dendritic density, increased numbers of activated microglia, and pronounced astrocytosis. Several recent studies show that brains of GFAP-gp120tg mice and neurocognitively impaired HIV patients share also a significant number of differentially regulated genes, activation of innate immunity and other cellular signaling pathways, disturbed neurogenesis, and learning deficits. These findings support the continued relevance of the GFAP-gp120tg mouse as a useful model to investigate neurodegenerative mechanisms and develop therapeutic strategies to mitigate the consequences associated with HIV infection of the CNS, neuroAIDS, and HAND.
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Complejo SIDA Demencia/genética , Disfunción Cognitiva/genética , Modelos Animales de Enfermedad , Proteína gp120 de Envoltorio del VIH/genética , VIH-1/genética , Complejo SIDA Demencia/inmunología , Complejo SIDA Demencia/fisiopatología , Animales , Astrocitos/inmunología , Astrocitos/patología , Encéfalo/inmunología , Encéfalo/patología , Disfunción Cognitiva/inmunología , Disfunción Cognitiva/fisiopatología , Regulación de la Expresión Génica , Proteína Ácida Fibrilar de la Glía/genética , Proteína Ácida Fibrilar de la Glía/inmunología , Proteína gp120 de Envoltorio del VIH/inmunología , VIH-1/química , Inmunidad Innata , Ratones , Ratones Transgénicos , Regiones Promotoras Genéticas , Proteínas Recombinantes de Fusión/genética , Proteínas Recombinantes de Fusión/inmunología , Transducción de Señal , Sinapsis/inmunología , Sinapsis/patologíaRESUMEN
HIV-1 infection frequently causes HIV-associated neurocognitive disorders (HAND) despite combination antiretroviral therapy (cART). Evidence is accumulating that components of cART can themselves be neurotoxic upon long-term exposure. In addition, abuse of psychostimulants, such as methamphetamine, seems to aggravate HAND and compromise antiretroviral therapy. However, the combined effect of virus and recreational and therapeutic drugs on the brain is poorly understood. Therefore, we exposed mixed neuronal-glial cerebrocortical cells to antiretrovirals (ARVs) (zidovudine [AZT], nevirapine [NVP], saquinavir [SQV], and 118-D-24) of four different pharmacological categories and to methamphetamine and, in some experiments, the HIV-1 gp120 protein for 24 h and 7 days. Subsequently, we assessed neuronal injury by fluorescence microscopy, using specific markers for neuronal dendrites and presynaptic terminals. We also analyzed the disturbance of neuronal ATP levels and assessed the involvement of autophagy by using immunofluorescence and Western blotting. ARVs caused alterations of neurites and presynaptic terminals primarily during the 7-day incubation and depending on the specific compounds and their combinations with and without methamphetamine. Similarly, the loss of neuronal ATP was context specific for each of the drugs or combinations thereof, with and without methamphetamine or viral gp120. Loss of ATP was associated with activation of AMP-activated protein kinase (AMPK) and autophagy, which, however, failed to restore normal levels of neuronal ATP. In contrast, boosting autophagy with rapamycin prevented the long-term drop of ATP during exposure to cART in combination with methamphetamine or gp120. Our findings indicate that the overall positive effect of cART on HIV infection is accompanied by detectable neurotoxicity, which in turn may be aggravated by methamphetamine.
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Proteína gp120 de Envoltorio del VIH/farmacología , Inhibidores de Integrasa VIH/farmacología , Metanfetamina/farmacología , Neuronas/efectos de los fármacos , Nevirapina/farmacología , Saquinavir/farmacología , Zidovudina/farmacología , Proteínas Quinasas Activadas por AMP/metabolismo , Adenosina Trifosfato/metabolismo , Animales , Autofagia/efectos de los fármacos , Técnicas de Cultivo de Célula , Corteza Cerebral/citología , Corteza Cerebral/efectos de los fármacos , Corteza Cerebral/metabolismo , Combinación de Medicamentos , Embrión de Mamíferos , Homeostasis/efectos de los fármacos , Neuroglía/citología , Neuroglía/efectos de los fármacos , Neuroglía/metabolismo , Neuronas/citología , Neuronas/metabolismo , Terminales Presinápticos/efectos de los fármacos , Ratas , Ratas Sprague-Dawley , Proteínas Recombinantes/farmacología , Sirolimus/farmacologíaRESUMEN
BACKGROUND: The chemokine receptor CXCR4 (CD184) and its natural ligand CXCL12 contribute to many physiological processes, including decisions about cell death and survival in the central nervous system. In addition, CXCR4 is a co-receptor for human immunodeficiency virus (HIV)-1 and mediates the neurotoxicity of the viral envelope protein gp120. However, we previously observed that CXCL12 also causes toxicity in cerebrocortical neurons but the cellular mechanism remained incompletely defined. METHODS: Primary neuronal-glial cerebrocortical cell cultures from rat were exposed to a neurotoxicity-inducing CXCL12 concentration for different times and the activity of the stress-associated mitogen-activated protein kinase p38 (p38 MAPK) was assessed using an in vitro kinase assay. Neurotoxicity of CXCL12 and cellular localization of p38 MAPK was analyzed by immunofluorescence microscopy. Pharmacological inhibition of NMDA-type glutamate receptor-gated ion channels (NMDAR) of L-type Ca2+ channels was employed during 12- and 24-h exposure to neurotoxic amounts of CXCL12 to study the effects on active p38 MAPK and neuronal survival by Western blotting and microscopy, respectively. Neurotoxicity of CXCL12 was also assessed during pharmacological inhibition of p38 MAPK. RESULTS: Here, we show that a neurotoxic amount of CXCL12 triggers a significant increase of endogenous p38 MAPK activity in cerebrocortical cells. Immunofluorescence and Western blotting experiments with mixed neuronal-glial and neuron-depleted glial cerebrocortical cells revealed that the majority of active/phosphorylated p38 MAPK was located in neurons. Blockade of NMDAR-gated ion channels or L-type Ca2+ channels both abrogated an increase of active p38 MAPK and toxicity of CXCL12 in cerebrocortical neurons. Inhibition of L-type Ca2+ channels with nimodipine kept the active kinase at levels not significantly different from baseline while blocking NMDAR with MK-801 strongly reduced phosphorylated p38 MAPK below baseline. Finally, we confirmed that directly blocking p38 MAPK also abrogated neurotoxicity of CXCL12. CONCLUSIONS: Our findings link CXCL12-induced neuronal death to the regulation of NMDAR-gated ion channels and L-type Ca2+ channels upstream of p38 MAPK activation.
RESUMEN
The innate immune system has been implicated in several neurodegenerative diseases, including HIV-1-associated dementia. In this study, we show that genetic ablation of CCR5 prevents microglial activation and neuronal damage in a transgenic model of HIV-associated brain injury induced by a CXCR4-using viral envelope gp120. The CCR5 knockout (KO) also rescues spatial learning and memory in gp120-transgenic mice. However, the CCR5KO does not abrogate astrocytosis, indicating it can occur independently from neuronal injury and behavioral impairment. To characterize further the neuroprotective effect of CCR5 deficiency we performed a genome-wide gene expression analysis of brains from HIVgp120tg mice expressing or lacking CCR5 and nontransgenic controls. A comparison with a human brain microarray study reveals that brains of HIVgp120tg mice and HIV patients with neurocognitive impairment share numerous differentially regulated genes. Furthermore, brains of CCR5 wild-type and CCR5KO gp120tg mice express markers of an innate immune response. One of the most significantly upregulated factors is the acute phase protein lipocalin-2 (LCN2). Using cerebrocortical cell cultures, we find that LCN2 is neurotoxic in a CCR5-dependent fashion, whereas inhibition of CCR5 alone is not sufficient to abrogate neurotoxicity of a CXCR4-using gp120. However, the combination of pharmacologic CCR5 blockade and LCN2 protects neurons from toxicity of a CXCR4-using gp120, thus recapitulating the finding in CCR5-deficient gp120tg mouse brain. Our study provides evidence for an indirect pathologic role of CCR5 and a novel protective effect of LCN2 in combination with inhibition of CCR5 in HIV-associated brain injury.
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Complejo SIDA Demencia/genética , Proteínas de Fase Aguda/metabolismo , Proteína gp120 de Envoltorio del VIH/genética , VIH-1 , Lipocalinas/metabolismo , Proteínas Oncogénicas/metabolismo , Receptores CCR5/genética , Proteínas de Fase Aguda/biosíntesis , Animales , Antagonistas de los Receptores CCR5 , Células Cultivadas , Modelos Animales de Enfermedad , Perfilación de la Expresión Génica , Gliosis , Lipocalina 2 , Lipocalinas/biosíntesis , Aprendizaje por Laberinto , Memoria , Ratones , Ratones Noqueados , Microglía/patología , Proteínas Oncogénicas/biosíntesis , Receptores CCR5/biosíntesis , Receptores CXCR4/metabolismo , Transducción de Señal/genéticaRESUMEN
INTRODUCTION: Pharmacotherapy for the management of obesity is primarily aimed at weight loss, weight loss maintenance and risk reduction (reduction in body fat, risk factors for cardiovascular disease and the incidence of diabetes mellitus). Among drugs that have been evaluated for weight loss include antidepressants (fluoxetine) and antiepileptic (topiramate). MATERIAL AND METHODS: We analyzed eating behavior and weight loss in a sample of morbid obesity patients before bariatric surgery. The patients suffering eating disturbances symptoms were grouped into three groups: one group received 40 mg of flouxetine/day (Group A); another group received topiramate 200 mg/day (Group B); and the third group of patients were treated with fluoxetine 40 mg and 200 mg of topiramate/day (Group C). RESULTS: Patients treated with fluoxetine plus topiramate lost more weight at 3 and 6 months before surgery. CONCLUSIONS: The use of the psychopharmaceutical drug (fluoxetine and topiramate) in morbid obese patients with eating disorders could represent a new approach to the management of eating behavior before bariatric surgery.
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Fármacos Antiobesidad/administración & dosificación , Cirugía Bariátrica , Conducta Alimentaria/efectos de los fármacos , Fluoxetina/administración & dosificación , Fructosa/análogos & derivados , Obesidad Mórbida/tratamiento farmacológico , Obesidad Mórbida/cirugía , Inhibidores Selectivos de la Recaptación de Serotonina/administración & dosificación , Adulto , Quimioterapia Combinada , Femenino , Fructosa/administración & dosificación , Humanos , Masculino , Cuidados Preoperatorios , TopiramatoRESUMEN
BACKGROUND: Obesity-induced hypogonadism (OIH) is a prevalent, but often neglected condition in men, which aggravates the metabolic complications of overweight. While hypothalamic suppression of Kiss1-encoded kisspeptin has been suggested to contribute to OIH, the molecular mechanisms for such repression in obesity, and the therapeutic implications thereof, remain unknown. METHODS: A combination of bioinformatic, expression and functional analyses was implemented, assessing the role of the evolutionary-conserved miRNAs, miR-137 and miR-325, in mediating obesity-induced suppression of hypothalamic kisspeptin, as putative mechanism of central hypogonadism and metabolic comorbidities. The implications of such miR-137/325-kisspeptin interplay for therapeutic intervention in obesity were also explored using preclinical OIH models. RESULTS: MiR-137/325 repressed human KISS1 3'-UTR in-vitro and inhibited hypothalamic kisspeptin content in male rats, while miR-137/325 expression was up-regulated, and Kiss1/kisspeptin decreased, in the medio-basal hypothalamus of obese rats. Selective over-expression of miR-137 in Kiss1 neurons reduced Kiss1/ kisspeptin and partially replicated reproductive and metabolic alterations of OIH in lean mice. Conversely, interference of the repressive actions of miR-137/325 selectively on Kiss1 3'-UTR in vivo, using target-site blockers (TSB), enhanced kisspeptin content and reversed central hypogonadism in obese rats, together with improvement of glucose intolerance, insulin resistance and cardiovascular and inflammatory markers, despite persistent exposure to obesogenic diet. Reversal of OIH by TSB miR-137/325 was more effective than chronic kisspeptin or testosterone treatments in obese rats. CONCLUSIONS: Our data disclose that the miR-137/325-Kisspeptin repressive interaction is a major player in the pathogenesis of obesity-induced hypogonadism and a putative druggable target for improved management of this condition and its metabolic comorbidities in men suffering obesity. SIGNIFICANCE STATEMENT: Up to half of the men suffering obesity display also central hypogonadism, an often neglected complication of overweight that can aggravate the clinical course of obesity and its complications. The mechanisms for such obesity-induced hypogonadism remain poorly defined. We show here that the evolutionary conserved miR137/miR325 tandem centrally mediates obesity-induced hypogonadism via repression of the reproductive-stimulatory signal, kisspeptin; this may represent an amenable druggable target for improved management of hypogonadism and other metabolic complications of obesity.
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Hipogonadismo , Hipotálamo , Kisspeptinas , MicroARNs , Obesidad , MicroARNs/genética , MicroARNs/metabolismo , Hipogonadismo/genética , Hipogonadismo/metabolismo , Hipogonadismo/complicaciones , Kisspeptinas/genética , Kisspeptinas/metabolismo , Animales , Obesidad/metabolismo , Obesidad/complicaciones , Obesidad/genética , Masculino , Ratas , Hipotálamo/metabolismo , Humanos , Ratones , Ratas Wistar , ComorbilidadRESUMEN
This study evaluated the in vivo therapeutic efficacy of oncolytic serotype 5 adenovirus TAV255 in CAR-deficient tumors. In vitro experiments were performed with cell lines that expressed different levels of CAR (HEK293, A549, CT26, 4T1, and MCF-7). Low CAR cells, such as CT26, were poorly transduced by Ad in vitro unless the adenovirus was encapsulated in liposomes. However, the CT26 tumor in an immune-competent mouse model responded to the unencapsulated TAV255; 33% of the tumors were induced into complete remission, and mice with complete remission rejected the rechallenge with cancer cell injection. Encapsulation of TAV255 improves its therapeutic efficacy by transducing more CT26 cells, as expected from in vitro results. In a bilateral tumor model, nonencapsulated TAV255 reduced the growth rate of the locally treated tumors but had no effect on the growth rate of the distant tumor site. Conversely, encapsulated TAV255-infected CT26 induced a delayed growth rate of both the primary injected tumor and the distant tumor, consistent with a robust immune response. In vivo, intratumorally injected unencapsulated adenoviruses infect CAR-negative cells with only limited efficiency. However, unencapsulated adenoviruses robustly inhibit the growth of CAR-deficient tumors, an effect that constitutes an 'in situ vaccination' by stimulating cytotoxic T cells.
RESUMEN
Adenovirus (Ad)-based vectors have shown considerable promise for gene therapy. However, Ad requires the coxsackievirus and adenovirus receptor (CAR) to enter cells efficiently and low CAR expression is found in many human cancers, which hinder adenoviral gene therapies. Here, cationic 1,2-dioleoyl-3-trimethylammonium-propane (DOTAP)-folate liposomes (Df) encapsulating replication-deficient Ad were synthesized, which showed improved transfection efficiency in various CAR-deficient cell lines, including epithelial and hematopoietic cell types. When encapsulating replication-competent oncolytic Ad (TAV255) in DOTAP-folate liposome (TAV255-Df), the adenoviral structural protein, hexon, was readily produced in CAR-deficient cells, and the tumor cell killing ability was 5× higher than that of the non-encapsulated Ad. In CAR-deficient CT26 colon carcinoma murine models, replication-competent TAV255-Df treatment of subcutaneous tumors by intratumoral injection resulted in 67% full tumor remission, prolonged survival, and anti-cancer immunity when mice were rechallenged with cancer cells with no further treatment. The preclinical data shows that DOTAP-folate liposomes could significantly enhance the transfection efficiency of Ad in CAR-deficient cells and, therefore, could be a feasible strategy for applications in cancer treatment.
Asunto(s)
Adenoviridae , Neoplasias , Ratones , Humanos , Animales , Adenoviridae/genética , Adenoviridae/metabolismo , Liposomas/metabolismo , Propano , Ácido Fólico/metabolismoRESUMEN
Adenovirus (Ad) is a widely studied viral vector for cancer therapy as it can be engineered to cause selective lysis of cancer cells. However, Ad delivery is limited in treating cancers that do not have coxsackievirus and adenovirus receptors (CAR). To overcome this challenge, Ad-encapsulated liposomes were developed that enhance the delivery of Ads and increase therapeutic efficacy. Cationic empty liposomes were manufactured first, to which an anionic Ad were added, which resulted in encapsulated Ad liposomes through charge interaction. Optimization of the liposome formula was carried out with series of formulation variables experiments using an extrusion process, which is ideal for laboratory-scale small batches. Later, the optimized formulation was manufactured with a homogenization technique-A high shear rotor-stator blending, that is ideal for large-scale manufacturing and is in compliance with Good Manufacturing Practices (GMP). Comparative in vitro transduction, physicochemical characterization, long-term storage stability at different temperature conditions, and in vivo animal studies were performed. Ad encapsulated liposomes transduced CAR deficient cells 100-fold more efficiently than the unencapsulated Ad (p ≤ 0.0001) in vitro, and 4-fold higher in tumors injected in nude mice in vivo. Both extrusion and homogenization performed similarly-with equivalent in vitro and in vivo transduction efficiencies, physicochemical characterization, and long-term storage stability. Thus, two Ad encapsulated liposomes preparation methods used herein, i.e., extrusion vs. homogenization were equivalent in terms of enhanced Ad performance and long-term storage stability; this will, hopefully, facilitate translation to the clinic.
RESUMEN
A crucial step in the arenavirus life cycle is the biosynthesis of the viral envelope glycoprotein (GP) responsible for virus attachment and entry. Processing of the GP precursor (GPC) by the cellular proprotein convertase site 1 protease (S1P), also known as subtilisin-kexin-isozyme 1 (SKI-1), is crucial for cell-to-cell propagation of infection and production of infectious virus. Here, we sought to evaluate arenavirus GPC processing by S1P as a target for antiviral therapy using a recently developed peptide-based S1P inhibitor, decanoyl (dec)-RRLL-chloromethylketone (CMK), and the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV). To control for off-target effects of dec-RRLL-CMK, we employed arenavirus reverse genetics to introduce a furin recognition site into the GPC of LCMV. The rescued mutant virus grew to normal titers, and the processing of its GPC critically depended on cellular furin, but not S1P. Treatment with the S1P inhibitor dec-RRLL-CMK resulted in specific blocking of viral spread and virus production of LCMV. Combination of the protease inhibitor with ribavirin, currently used clinically for treatment of human arenavirus infections, resulted in additive drug effects. In cells deficient in S1P, the furin-dependent LCMV variant established persistent infection, whereas wild-type LCMV underwent extinction without the emergence of S1P-independent escape variants. Together, the potent antiviral activity of an inhibitor of S1P-dependent GPC cleavage, the additive antiviral effect with ribavirin, and the low probability of emergence of S1P-independent viral escape variants make S1P-mediated GPC processing by peptide-derived inhibitors a promising strategy for the development of novel antiarenaviral drugs.
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Antivirales/farmacología , Virus de la Coriomeningitis Linfocítica/efectos de los fármacos , Proproteína Convertasas/antagonistas & inhibidores , Inhibidores de Proteasas/farmacología , Proteínas del Envoltorio Viral/metabolismo , Animales , Arenavirus/efectos de los fármacos , Línea Celular , Sistemas de Liberación de Medicamentos/métodos , Sinergismo Farmacológico , Glicoproteínas/metabolismo , Humanos , Péptido Hidrolasas/metabolismo , Péptidos/farmacología , Proproteína Convertasas/metabolismo , Inhibidores de Proteasas/uso terapéutico , Ribavirina/farmacología , Serina Endopeptidasas/metabolismoRESUMEN
The Old World arenavirus Lassa virus (LASV) is the causative agent of severe viral hemorrhagic fever (VHF) in humans and is the most prevalent human pathogen among arenaviruses. The present study investigated the largely unknown mechanisms of cell entry of LASV, a process know to be mediated solely by the virus envelope glycoprotein (GP). To circumvent biosafety restrictions associated with the use of live LASV, we used reverse genetics to generate a recombinant variant of the prototypic arenavirus lymphocytic choriomeningitis virus (LCMV) expressing the LASV GP (rLCMV-LASVGP). The rescued rLCMV-LASVGP grew to titers comparable to that of LCMV and showed the receptor binding characteristics of LASV. We used rLCMV-LASVGP to characterize the cellular mechanisms of LASV entry in the context of a productive arenavirus infection. The kinetics of pH-dependent membrane fusion of rLCMV-LASVGP resembled those of the human-pathogenic New World arenavirus Junin virus (JUNV) and other enveloped viruses that use clathrin-mediated endocytosis for entry. However, rLCMV-LASVGP entered cells predominantly via a clathrin-, caveolin-, and dynamin-independent endocytotic pathway similar to the one recently described for LCMV. Productive infection of rLCMV-LASVGP was only mildly affected by a dominant negative mutant of Rab5 and was independent of Rab7, suggesting an unusual mechanism of delivery to endosomes. In addition, rLCMV-LASVGP infection was independent of actin but required intact microtubules. Our data indicate that LASV enters cells via a pathway distinct from the one used by human-pathogenic New World arenaviruses.
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Arenavirus del Viejo Mundo/fisiología , Virus Lassa/genética , Virus de la Coriomeningitis Linfocítica/genética , Internalización del Virus , Actinas/genética , Animales , Arenavirus del Nuevo Mundo/fisiología , Línea Celular , Chlorocebus aethiops , Cricetinae , Endocitosis , Endosomas/virología , Humanos , Concentración de Iones de Hidrógeno , Microtúbulos/virología , Factores de Tiempo , Proteínas de Unión al GTP rab/genética , Proteínas de Unión al GTP rab5/genética , Proteínas de Unión a GTP rab7RESUMEN
Multiple mechanisms appear to contribute to neuronal stress and injury underlying HIV-associated neurocognitive disorders (HAND), which occur despite the successful introduction of combination antiretroviral therapy (cART). Evidence is accumulating that components of cART can itself be neurotoxic upon long-term exposure. In addition, abuse of psychostimulants, such as methamphetamine (METH), seems to compromise antiretroviral therapy and aggravate HAND. However, the combined effect of virus and recreational and therapeutic drugs on the brain is still incompletely understood. However, several lines of evidence suggest a shared critical role of oxidative stress, compromised neuronal energy homeostasis and autophagy in promotion and prevention of neuronal dysfunction associated with HIV-1 infection, cART and psychostimulant use. In this review, we present a synopsis of recent work related to neuronal stress and injury induced by HIV infection, antiretrovirals (ARVs) and the highly addictive psychostimulant METH.
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Infection with human immunodeficiency virus-1 (HIV-1) causes brain injury. Type I interferons (IFNα/ß) are critical mediators of any anti-viral immune response and IFNß has been implicated in the temporary control of lentiviral infection in the brain. Here we show that transgenic mice expressing HIV-1 envelope glycoprotein 120 in their central nervous system (HIVgp120tg) mount a transient IFNß response and provide evidence that IFNß confers neuronal protection against HIVgp120 toxicity. In cerebrocortical cell cultures, neuroprotection by IFNß against gp120 toxicity is dependent on IFNα receptor 1 (IFNAR1) and the ß-chemokine CCL4, as IFNAR1 deficiency and neutralizing antibodies against CCL4, respectively, abolish the neuroprotective effects. We find in vivo that IFNß mRNA is significantly increased in HIVgp120tg brains at 1.5, but not 3 or 6 months of age. However, a four-week intranasal IFNß treatment of HIVgp120tg mice starting at 3.5 months of age increases expression of CCL4 and concomitantly protects neuronal dendrites and pre-synaptic terminals in cortex and hippocampus from gp120-induced damage. Moreover, in vivo and in vitro data suggests astrocytes are a major source of IFNß-induced CCL4. Altogether, our results suggest exogenous IFNß as a neuroprotective factor that has potential to ameliorate in vivo HIVgp120-induced brain injury.
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Lesiones Encefálicas/prevención & control , Modelos Animales de Enfermedad , Interferón beta/farmacología , Neuronas/efectos de los fármacos , Fármacos Neuroprotectores/farmacología , Animales , Lesiones Encefálicas/virología , Células Cultivadas , Quimiocina CCL4/genética , Quimiocina CCL4/metabolismo , Expresión Génica/efectos de los fármacos , Proteína gp120 de Envoltorio del VIH/antagonistas & inhibidores , Proteína gp120 de Envoltorio del VIH/genética , Proteína gp120 de Envoltorio del VIH/metabolismo , VIH-1/fisiología , Humanos , Interferón beta/genética , Interferón beta/metabolismo , Ratones Transgénicos , Neuronas/patología , Neuronas/virología , Ratas , Receptor de Interferón alfa y beta/genética , Receptor de Interferón alfa y beta/metabolismoRESUMEN
Oranges are clinically relevant allergenic foods. To date, orange allergens have not been characterized in detail. The study is aimed at analyzing the sensitization profile in orange-sensitized subjects with and without clinical allergy, and to identify orange allergens. Fifty-six sensitized subjects with self-reported reactions to orange were grouped into reactors (anaphylaxis or multiple episodes of immediate reactions and/or positive challenge tests) and non-reactors (negative open food challenge tests). Allergens were characterized by IgE immunoblotting, N-terminal sequencing, IgE-inhibition assays, and mediator release assays were performed to determine the allergenic potency of orange profilin. Of 56 subjects, 23 were classified as orange allergic showing mainly an oral allergy syndrome. Of 23 subjects classified as orange allergic, 22 were sensitized to profilin, Cit s 2. In patients with mono-sensitization to profilin in vitro histamine releases up to 75% from basophils were induced using orange extract and purified plant profilins. Of the allergic patients 78% were sensitized to germin-like protein, Cit s 1. Both allergens showed retained IgE reactivity in heat-processed orange juice. Interestingly, subjects with and without clinical allergy showed a comparable sensitization profile. Profilin and germin-like proteins are major orange allergens. The potential clinical relevance of orange profilin was indicated by its strong capacity to release histamine from basophils. However, a predominant sensitization to both allergens in subjects without symptoms also indicates a high frequency of clinically insignificant sensitization.
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Alérgenos/análisis , Citrus sinensis/inmunología , Frutas/inmunología , Glicoproteínas/análisis , Proteínas de Plantas/análisis , Profilinas/análisis , Alérgenos/química , Antígenos de Plantas , Basófilos/efectos de los fármacos , Basófilos/fisiología , Hipersensibilidad a los Alimentos/inmunología , Humanos , Inmunoglobulina E/sangre , Inmunoglobulina E/inmunología , Fragmentos de Péptidos/químicaRESUMEN
INTRODUCTION. The challenge of early detection can be tackled from an evolutionary perspective. Early intervention treatments have shown themselves to be effective provided that they are applied systematically as part of the strategic planning of the treatment. AIMS. The aim of this study is to provide an updated review in response to the criticism targeted towards early detection and to offer some considerations on the intervention strategy. Our research is based on a review of the early care techniques that are commonly used within the field of autism and it intends to reflect the most significant aspects that can be deduced from the experiments and studies carried out to date. CONCLUSIONS. From the findings of the review it can be concluded that early detection may be more efficient if carried out within the framework of developmental surveillance, which also offers the opportunity to provide guidance on the child's development. Early care is an effective resource for attending to the needs of children with autism. Professionals have the duty to assess the work they do on available treatments with a reflexive, judicious attitude, taking into account the values and preferences of the families. Programmes must focus on the core symptoms and apply the active ingredients of the treatment.
TITLE: De la deteccion precoz a la atencion temprana: estrategias de intervencion a partir del cribado prospectivo.Introduccion. El reto de la deteccion precoz puede realizarse desde una perspectiva evolutiva. Los tratamientos de intervencion temprana han demostrado su eficacia siempre y cuando se apliquen sistematicamente en el marco de una planificacion estrategica del tratamiento. Objetivos. Proporcionar una revision actualizada para responder a las criticas a la deteccion precoz y aportar una reflexion sobre la estrategia de intervencion, basada en la revision de las tecnicas de atencion temprana usuales en el campo del autismo, reflejando los aspectos mas relevantes que se deducen de las experiencias y estudios llevados a cabo hasta el momento. Conclusiones. Tras la revision realizada se concluye que la deteccion precoz puede ser mas eficiente si se lleva a cabo en el marco de la vigilancia del desarrollo, que ademas ofrece la oportunidad de proporcionar orientacion sobre el desarrollo del menor. La atencion temprana constituye un recurso eficaz para atender las necesidades del menor con autismo. Los profesionales tienen la responsabilidad de evaluar el trabajo que hacen con una actitud reflexiva y critica sobre los tratamientos disponibles tomando en consideracion los valores y las preferencias de las familias. Los programas deben centrarse en los sintomas nucleares aplicando ingredientes activos del tratamiento.
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Trastorno Autístico/diagnóstico , Trastorno Autístico/terapia , Niño , Diagnóstico Precoz , Intervención Médica Temprana , HumanosRESUMEN
Methamphetamine (METH) abuse is frequent in individuals infected with human immunodeficiency virus type-1 (HIV-1) and is suspected to aggravate HIV-associated neurocognitive disorders (HAND). METH is a psychostimulant that compromises several neurotransmitter systems and HIV proteins trigger neuronal injury but the combined effects of viral infection and METH abuse are incompletely understood. In this study we treated transgenic mice expressing the HIV envelope protein gp120 in the brain (HIV-1 gp120tg) at 3-4 months of age with an escalating-dose, multiple-binge METH regimen. The long-term effects were analyzed after 6-7 months of drug abstinence employing behavioral tests and analysis of neuropathology, electrophysiology and gene expression. Behavioral testing showed that both HIV-1 gp120tg and WT animals treated with METH displayed impaired learning and memory. Neuropathological analysis revealed that METH similar to HIV-1 gp120 caused a significant loss of neuronal dendrites and pre-synaptic terminals in hippocampus and cerebral cortex of WT animals. Electrophysiological studies in hippocampal slices showed that METH exposed HIV-1 gp120tg animals displayed reduced post-tetanic potentiation, whereas both gp120 expression and METH lead to reduced long-term potentiation. A quantitative reverse transcription-polymerase chain reaction array showed that gp120 expression, METH and their combination each caused a significant dysregulation of specific components of GABAergic and glutamatergic neurotransmission systems, providing a possible mechanism for synaptic dysfunction and behavioral impairment. In conclusion, both HIV-1 gp120 and METH caused lasting behavioral impairment in association with neuropathology and altered gene expression. However, combined METH exposure and HIV-1 gp120 expression resulted in the most pronounced, long lasting pre- and post-synaptic alterations coinciding with impaired learning and memory.
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Encéfalo/efectos de los fármacos , Encéfalo/patología , Infecciones por VIH/complicaciones , Metanfetamina/efectos adversos , Trastornos Relacionados con Sustancias/complicaciones , Animales , Conducta Animal/efectos de los fármacos , Encéfalo/virología , Estimulantes del Sistema Nervioso Central/efectos adversos , Proteína gp120 de Envoltorio del VIH , VIH-1 , Inmunohistoquímica , Ratones , Ratones Transgénicos , Técnicas de Placa-Clamp , Reacción en Cadena de la Polimerasa de Transcriptasa Inversa , Transcriptoma/efectos de los fármacosRESUMEN
This study investigates the relationship of promoter methylation in tumor suppressor genes with copy-number aberrations (CNA) and with tumor markers in breast cancer (BCs). The study includes 98 formalin fixed paraffin-embedded BCs in which promoter methylation of 24 tumour suppressor genes were assessed by Methylation-Specific Multiplex Ligation-dependent Probe Amplification (MS-MLPA), CNA of 20 BC related genes by MLPA and ER, PR, HER2, CK5/6, CK18, EGFR, Cadherin-E, P53, Ki-67 and PARP expression by immunohistochemistry (IHC). Cluster analysis classed BCs in two groups according to promoter methylation percentage: the highly-methylated group (16 BCs), containing mostly hyper-methylated genes, and the sparsely-methylated group (82 BCs) with hypo-methylated genes. ATM, CDKN2A, VHL, CHFR and CDKN2B showed the greatest differences in the mean methylation percentage between these groups. We found no relationship of the IHC parameters or pathological features with methylation status, except for Catherin-E (p = 0.008). However the highly methylated BCs showed higher CNA proportion than the sparsely methylated BCs (p < 0.001, OR = 1.62; IC 95% [1.26, 2.07]). CDC6, MAPT, MED1, PRMD14 and AURKA showed the major differences in the CNA percentage between the two groups, exceeding the 22%. Methylation in RASSF1, CASP8, DAPK1 and GSTP1 conferred the highest probability of harboring CNA. Our results show a new link between promoter methylation and CNA giving support to the importance of methylation events to establish new BCs subtypes. Our findings may be also of relevance in personalized therapy assessment, which could benefit the hyper methylated BC patients group.