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Viral infections of the central nervous system (CNS) often cause worse neurological outcomes in younger hosts. Throughout childhood, the brain undergoes extensive development and refinement to produce functional neural networks. Network function is maintained partly with the help of neural stem cells (NSCs) that replace neuronal and glia subtypes in the two neurogenic niches of the brain (the hippocampus and subventricular zone). Accumulating evidence suggests that viruses disrupt NSC function in adulthood and infancy, but the in vivo impact of childhood infections on acute and long-term NSC function is unknown. Using a juvenile mouse model of measles virus (MeV) infection, where only mature neurons in the brain are infected, we defined the effects of the antiviral immune response on NSCs from juvenile to adult stages of life. We found that (a) virus persists in the brains of survivors despite an anti-viral immune response; (b) NSC numbers decrease dramatically during early infection, but ultimately stabilize in adult survivors; (c) infection is associated with mild apoptosis throughout the juvenile brain, but NSC proliferation is unchanged; (d) the loss of NSC numbers is dependent upon the stage of NSC differentiation; and (e) immature neurons increase early during infection, concurrent with depletion of NSC pools. Collectively, we show that NSCs are exquisitely sensitive to the inflammatory microenvironment created during neuron-restricted MeV infection in juveniles, responding with an early loss of NSCs but increased neurogenesis. These studies provide insight into potential cellular mechanisms associated with long-term neurological deficits in survivors of childhood CNS infections.
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Células-Tronco Neurais , Vírus , Camundongos , Animais , Neurônios , Encéfalo , Diferenciação Celular , NeurogêneseRESUMO
Reactive microglia are observed with aging and in Lewy body disorders, including within the olfactory bulb of men with Parkinson's disease. However, the functional impact of microglia in these disorders is still debated. Resetting these reactive cells by a brief dietary pulse of the colony-stimulating factor 1 receptor (CSF1R) inhibitor PLX5622 may hold therapeutic potential against Lewy-related pathologies. To our knowledge, withdrawal of PLX5622 after short-term exposure has not been tested in the preformed α-synuclein fibril (PFF) model, including in aged mice of both sexes. Compared to aged female mice, we report that aged males on the control diet showed higher numbers of phosphorylated α-synuclein+ inclusions in the limbic rhinencephalon after PFFs were injected in the posterior olfactory bulb. However, aged females displayed larger inclusion sizes compared to males. Short-term (14-day) dietary exposure to PLX5622 followed by control chow reduced inclusion numbers and levels of insoluble α-synuclein in aged males-but not females-and unexpectedly raised inclusion sizes in both sexes. Transient delivery of PLX5622 also improved spatial reference memory in PFF-infused aged mice, as evidenced by an increase in novel arm entries in a Y-maze. Superior memory was positively correlated with inclusion sizes but negatively correlated with inclusion numbers. Although we caution that PLX5622 delivery must be tested further in models of α-synucleinopathy, our data suggest that larger-sized-but fewer-α-synucleinopathic structures are associated with better neurological outcomes in PFF-infused aged mice.
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Doença por Corpos de Lewy , Doença de Parkinson , Sinucleinopatias , Masculino , Feminino , Camundongos , Animais , alfa-Sinucleína , Sinucleinopatias/patologia , Doença por Corpos de Lewy/patologia , Doença de Parkinson/patologiaRESUMO
Curriculum guidelines for virology are needed to best guide student learning due to the continuous and ever-increasing volume of virology information, the need to ensure that undergraduate and graduate students have a foundational understanding of key virology concepts, and the importance in being able to communicate that understanding to both other virologists and nonvirologists. Such guidelines, developed by virology educators and the American Society for Virology Education and Career Development Committee, are described herein.
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Currículo , Universidades , Virologia , Educação de Pós-Graduação , Estados Unidos , Virologia/educaçãoRESUMO
Viruses induce a wide range of neurological sequelae through the dysfunction and death of infected cells and persistent inflammation in the brain. Neural stem cells (NSCs) are often disturbed during viral infections. Although some viruses directly infect and kill NSCs, the antiviral immune response may also indirectly affect NSCs. To better understand how NSCs are influenced by a productive immune response, where the virus is successfully resolved and the host survives, we used the CD46+ mouse model of neuron-restricted measles virus (MeV) infection. As NSCs are spared from direct infection in this model, they serve as bystanders to the antiviral immune response initiated by selective infection of mature neurons. MeV-infected mice showed distinct regional and temporal changes in NSCs in the primary neurogenic niches of the brain, the hippocampus and subventricular zone (SVZ). Hippocampal NSCs increased throughout the infection (7 and 60 days post-infection; dpi), while mature neurons transiently declined at 7 dpi and then rebounded to basal levels by 60 dpi. In the SVZ, NSC numbers were unchanged, but mature neurons declined even after the infection was controlled at 60 dpi. Further analyses demonstrated sex, temporal, and region-specific changes in NSC proliferation and neurogenesis throughout the infection. A relatively long-term increase in NSC proliferation and neurogenesis was observed in the hippocampus; however, neurogenesis was reduced in the SVZ. This decline in SVZ neurogenesis was associated with increased immature neurons in the olfactory bulb in female, but not male mice, suggesting potential migration of newly-made neurons out of the female SVZ. These sex differences in SVZ neurogenesis were accompanied by higher infiltration of B cells and greater expression of interferon-gamma and interleukin-6 in female mice. Learning, memory, and olfaction tests revealed no overt behavioral changes after the acute infection subsided. These results indicate that antiviral immunity modulates NSC activity in adult mice without inducing gross behavioral deficits among those tested, suggestive of mechanisms to restore neurons and maintain adaptive behavior, but also revealing the potential for robust NSC disruption in subclinical infections.
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Neural stem/progenitor cells (NPSCs) express receptors for many inflammatory cytokines, with varying effects on differentiation and proliferation depending on the stage of development and the milieu of inflammatory mediators. In primary neurons and astrocytes, we recently showed that interferon gamma (IFNγ), a potent antiviral cytokine that is required for the control and clearance of many central nervous system (CNS) infections, could differentially affect cell survival and cell cycle progression depending upon the cell type and the profile of activated intracellular signaling molecules. Here, we show that IFNγ inhibits proliferation of primary NSPCs through dephosphorylation of the tumor suppressor Retinoblastoma protein (pRb), which is dependent on activation of signal transducers and activators of transcription-1 (STAT1) signaling pathways. Our results show i) IFNγ inhibits neurosphere growth and proliferation rate in a dose-dependent manner; ii) IFNγ blocks cell cycle progression through a late-stage G1/S phase restriction; iii) IFNγ induces phosphorylation and expression of STAT1 and STAT3; iv) IFNγ decreases cyclin E/cdk2 expression and reduces phosphorylation of cyclin D1 and pRb on serine residue 795; and v) the effects of IFNγ on NSPC proliferation, cell cycle protein expression, and pRb phosphorylation are STAT1-dependent. These data define a mechanism by which IFNγ could contribute to a reduction in NSPC proliferation in inflammatory conditions. Further delineation of the effects of inflammatory cytokines on NSPC growth could improve our understanding of how CNS infections and other inflammatory events disrupt brain development and NSPC function. © 2016 The Authors. Journal of Neuroscience Research Published by Wiley Periodicals, Inc.
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Antivirais/farmacologia , Proliferação de Células/efeitos dos fármacos , Interferon gama/farmacologia , Células-Tronco Neurais/efeitos dos fármacos , Proteína do Retinoblastoma/metabolismo , Fator de Transcrição STAT1/metabolismo , Animais , Ciclo Celular/efeitos dos fármacos , Ciclo Celular/genética , Proliferação de Células/genética , Células Cultivadas , Ciclinas/metabolismo , Relação Dose-Resposta a Droga , Embrião de Mamíferos , Regulação da Expressão Gênica/efeitos dos fármacos , Regulação da Expressão Gênica/genética , Camundongos , Camundongos Knockout , Fosforilação/efeitos dos fármacos , Proteína do Retinoblastoma/genética , Fator de Transcrição STAT1/genética , Fator de Transcrição STAT3/metabolismo , Serina/metabolismo , Fatores de Tempo , Proteína Supressora de Tumor p53RESUMO
BACKGROUND: In the developing brain, self-renewing neural stem/progenitor cells (NSPC) give rise to neuronal and glial lineages. NSPC survival and differentiation can be altered by neurotropic viruses and by the anti-viral immune response. Several neurotropic viruses specifically target and infect NSPCs, in addition to inducing neuronal loss, which makes it difficult to distinguish between effects on NSPCs that are due to direct viral infection or due to the anti-viral immune response. METHODS: We have investigated the impact of anti-viral immunity on NSPCs in measles virus (MV)-infected neonates. A neuron-restricted viral infection model was used, where NSPCs remain uninfected. Thus, an anti-viral immune response was induced without the confounding issue of NSPC infection. Two-transgenic mouse lines were used: CD46+ mice express the human isoform of CD46, the MV entry receptor, under the control of the neuron-specific enolase promoter; CD46+/IFNγ-KO mice lack the key anti-viral cytokine IFNγ. Multi-color flow cytometry and Western Blot analysis were used to quantify effects on NSPC, neuronal, and glial cell number, and quantify effects on IFNγ-mediated signaling and cell markers, respectively. RESULTS: Flow cytometric analysis revealed that NSPCs were reduced in CD46+/IFNγ-KO mice at 3, 7, and 10 days post-infection (dpi), but were unaffected in CD46+ mice. Early neurons showed the greatest cell loss at 7 dpi in both genotypes, with no effect on mature neurons and glial cells. Thus, IFNγ protected against NSPC loss, but did not protect young neurons. Western Blot analyses on hippocampal explants showed reduced nestin expression in the absence of IFNγ, and reduced doublecortin and ßIII-tubulin in both genotypes. Phosphorylation of STAT1 and STAT2 occurred independently of IFNγ in the hippocampus, albeit with distinct regulation of activation. CONCLUSIONS: This is the first study to demonstrate bystander effects of anti-viral immunity on NSPC function. Our results show IFNγ protects the NSPC population during a neonatal viral CNS infection. Significant loss of NSPCs in CD46+/IFNγ-KO neonates suggests that the adaptive immune response is detrimental to NSPCs in the absence of IFNγ. These results reveal the importance and contribution of the anti-viral immune response to neuropathology and may be relevant to other neuroinflammatory conditions.
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Encéfalo/patologia , Encéfalo/virologia , Regulação Viral da Expressão Gênica/fisiologia , Interferon gama/metabolismo , Sarampo/patologia , Células-Tronco Neurais/fisiologia , Animais , Animais Recém-Nascidos , Apoptose/fisiologia , Diferenciação Celular/genética , Modelos Animais de Doenças , Proteínas do Domínio Duplacortina , Regulação Viral da Expressão Gênica/genética , Interferon gama/genética , Células Matadoras Naturais/metabolismo , Sarampo/complicações , Sarampo/virologia , Vírus do Sarampo/fisiologia , Proteína Cofatora de Membrana/genética , Proteína Cofatora de Membrana/metabolismo , Camundongos , Camundongos Transgênicos , Proteínas Associadas aos Microtúbulos/metabolismo , Nestina/genética , Nestina/metabolismo , Neuroglia/metabolismo , Neuroglia/patologia , Neuroglia/virologia , Neuropeptídeos/metabolismo , Fator de Transcrição STAT2/metabolismo , Tubulina (Proteína)/metabolismoRESUMO
The signal transduction molecule, Stat1, is critical for the expression of type I and II interferon (IFN)-responsive genes in most cells; however, we previously showed that primary hippocampal mouse neurons express low basal Stat1, with delayed and attenuated expression of IFN-responsive genes. Moreover, IFNγ-dependent resolution of a neurotropic viral challenge in permissive mice is Stat1-independent. Here, we show that exogenous IFNγ has no deleterious impact on neuronal viability, and staurosporine-induced apoptosis in neurons is significantly blunted by the addition of IFNγ, suggesting that IFNγ confers a pro-survival signal in neurons. To identify the pathways induced by IFNγ in neurons, the activation of alternative signal transducers associated with IFNγ signaling was assessed. Rapid and pronounced activation of extracellular signal regulated kinase (Erk1/2) was observed in neurons, compared to a modest response in fibroblasts. Moreover, the absence of Stat1 in primary fibroblasts led to enhanced Erk activation following IFNγ addition, implying that the cell-specific availability of signal transducers can diversify the cellular response following IFN engagement.
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Interferon gama/farmacologia , Neurônios/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Transdução de Sinais/efeitos dos fármacos , Animais , Antimetabólitos/farmacologia , Bromodesoxiuridina/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Citosol/metabolismo , Feminino , Hipocampo/citologia , Hipocampo/embriologia , Sistema de Sinalização das MAP Quinases/efeitos dos fármacos , Camundongos , Camundongos Transgênicos , Neuroglia/efeitos dos fármacos , Gravidez , Cultura Primária de Células , Inibidores de Proteínas Quinases/farmacologia , Estaurosporina/farmacologiaRESUMO
Ebola virus disease (EVD) poses significant clinical care implications for pharmacists. Emergency preparedness efforts should be undertaken to ensure vital response to EVD. Pharmacists should consider factors such as enhanced use of resources for front-line EVD patient care along with procurement of investigational medications. Appropriate and timely preparation, distribution, and administration of treatment for patients with EVD in the setting of substantial critical illness as well as infection control measures are essential. Aggressive supportive care and early, goal-directed therapy are cornerstones of therapy, whereas investigational treatments for EVD will likely play a larger, more well-defined role as future clinical trials are conducted.
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Doença pelo Vírus Ebola/terapia , Serviço de Farmácia Hospitalar/organização & administração , Estado Terminal , Humanos , Controle de Infecções , FarmacêuticosRESUMO
Neurons are chiefly nonrenewable; thus, cytolytic immune strategies to clear or control neurotropic viral infections could have lasting neurologic consequences. IFN-γ is a potent antiviral cytokine that is critical for noncytolytic clearance of multiple neurotropic viral infections, including measles virus (MV); however, the downstream pathways through which IFN-γ functions in neurons have not been defined. Unlike most cell types studied to date in which IFN-γ affects gene expression via rapid and robust activation of STAT1, basal STAT1 levels in primary hippocampal neurons are constitutively low, resulting in attenuated STAT1 activation and consequently slower kinetics of IFN-γ-driven STAT1-dependent gene expression. Given this altered expression and activation of STAT1 in neurons, we sought to determine whether STAT1 was required for IFN-γ-mediated protection from infection in neurons. To do so, we evaluated the consequences of MV challenge of STAT1-deficient mice and primary hippocampal neurons explanted from these mice. Surprisingly, the absence of STAT1 did not restrict the ability of IFN-γ to control viral infection either in vivo or ex vivo. Moreover, the canonical IFN-γ-triggered STAT1 gene expression profile was not induced in STAT1-deficient neurons, suggesting that IFN-γ regulates neuronal STAT1-independent pathways to control viral replication.
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Interferon gama/imunologia , Vírus do Sarampo/imunologia , Sarampo/imunologia , Neurônios/imunologia , Neurônios/virologia , Fator de Transcrição STAT1/metabolismo , Animais , Células Cultivadas , Hipocampo/citologia , Hipocampo/imunologia , Hipocampo/metabolismo , Interferon gama/metabolismo , Sarampo/metabolismo , Sarampo/virologia , Vírus do Sarampo/patogenicidade , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Neurônios/metabolismo , Fator de Transcrição STAT1/deficiência , Fator de Transcrição STAT1/genética , Replicação ViralRESUMO
Viruses that infect the central nervous system (CNS) are associated with developmental abnormalities as well as neuropsychiatric and degenerative conditions. Many of these viruses such as Zika virus (ZIKV), cytomegalovirus (CMV), and herpes simplex virus (HSV) demonstrate tropism for neural stem cells (NSCs). NSCs are the multipotent progenitor cells of the brain that have the ability to form neurons, astrocytes, and oligodendrocytes. Viral infections often alter the function of NSCs, with profound impacts on the growth and repair of the brain. There are a wide spectrum of effects on NSCs, which differ by the type of virus, the model system, the cell types studied, and the age of the host. Thus, it is a challenge to predict and define the consequences of interactions between viruses and NSCs. The purpose of this review is to dissect the mechanisms by which viruses can affect survival, proliferation, and differentiation of NSCs. This review also sheds light on the contribution of key antiviral cytokines in the impairment of NSC activity during a viral infection, revealing a complex interplay between NSCs, viruses, and the immune system.
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Doenças do Sistema Nervoso Central/virologia , Células-Tronco Neurais/virologia , Viroses/virologia , Fenômenos Fisiológicos Virais , Animais , Doenças do Sistema Nervoso Central/genética , Doenças do Sistema Nervoso Central/imunologia , Citocinas/genética , Citocinas/imunologia , Humanos , Células-Tronco Neurais/imunologia , Vírus/genéticaRESUMO
Lipidoid nanoparticles (LNPs) are the delivery platform in Onpattro, the first FDA-approved siRNA drug. LNPs are also the carriers in the Pfizer-BioNTech and Moderna COVID-19 mRNA vaccines. While these applications have demonstrated that LNPs effectively deliver nucleic acids to hepatic and muscle cells, it is unclear if LNPs could be used for delivery of siRNA to neural cells, which are notoriously challenging delivery targets. Therefore, the purpose of this study was to determine if LNPs could efficiently deliver siRNA to neurons. Because of their potential delivery utility in either applications for the central nervous system and the peripheral nervous system, we used both cortical neurons and sensory neurons. We prepared siRNA-LNPs using C12-200, a benchmark ionizable cationic lipidoid along with helper lipids. We demonstrated using dynamic light scattering that the inclusion of both siRNA and PEG-lipid provided a stabilizing effect to the LNP particle diameters and polydispersity indices by minimizing aggregation. We found that siRNA-LNPs were safely tolerated by primary dorsal root ganglion neurons. Flow cytometry analysis revealed that Cy5 siRNA delivered via LNPs into rat primary cortical neurons showed uptake levels similar to Lipofectamine RNAiMAX-the gold standard commercial transfection agent. However, LNPs demonstrated a superior safety profile, whereas the Lipofectamine-mediated uptake was concomitant with significant toxicity. Fluorescence microscopy demonstrated a time-dependent increase in the uptake of LNP-delivered Cy5 siRNA in a human cortical neuron cell line. Overall, our results suggest that LNPs are a viable platform that can be optimized for delivery of therapeutic siRNAs to neural cells.
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Gânglios Espinais/metabolismo , Lipídeos/química , Nanopartículas , Neurônios/metabolismo , RNA Interferente Pequeno/administração & dosagem , Terapêutica com RNAi , Transfecção , Animais , Carbocianinas/metabolismo , Corantes Fluorescentes/metabolismo , Gânglios Espinais/citologia , Humanos , Células MCF-7 , Microscopia de Fluorescência , Nanotecnologia , Cultura Primária de Células , RNA Interferente Pequeno/genética , RNA Interferente Pequeno/metabolismo , Ratos , Fatores de TempoRESUMO
Ribavirin is a water-soluble antiviral compound which, owing to its inability to cross the blood-brain barrier, has limited effectiveness in treating viruses affecting the central nervous system. Direct nose-to-brain delivery was investigated for ribavirin in combination with poloxamer 188, an excipient known to enhance the absorption of drug compounds administered intranasally. Composite solid microparticles suitable for intranasal insufflation were prepared by suspending fine crystals of ribavirin in a matrix of poloxamer 188, which were cryogenically milled and characterized to ensure that ribavirin remained stable throughout preparation. In vitro diffusion of ribavirin across a semi-permeable regenerated cellulose membrane showed comparable cumulative drug release after 180 min from both fine solid particles (<20 µm) and 1:1 ribavirin:poloxamer microparticles (d50 = 20 µm); however, the initial release from polymer microparticles was slower, owing to gel formation on the membrane surface. When solid ribavirin was directly deposited on excised olfactory mucosa, either as fine drug particles or 1:1 ribavirin:poloxamer microparticles, permeation was significantly increased from microparticles containing poloxamer 188, suggesting additional interactions between the polymer and olfactory mucosa. These data indicate that for highly water-soluble drugs such as ribavirin or drugs subject to efflux by the nasal mucosa, a formulation of poloxmer-containing microparticles can enhance permeability across the olfactory epithelium and may improve direct nose-to-brain transport.
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Most pharmacy faculty members are more confident in their foundation as research scientists or clinical pharmacists than with the scholarship of teaching and learning (SoTL). However, many wish to enter this rewarding field of scholarship in order to test pedagogical innovations, measure teaching effectiveness, and share success with the Academy. This commentary provides general advice for those who wish to explore SoTL but lack formal education and training in this area. Four opportunities are highlighted: educational research, small activities and projects, course redesign, and longitudinal assessment and evaluation.
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Educação em Farmácia/métodos , Docentes , Bolsas de Estudo/métodos , Humanos , Aprendizagem , Estudos Longitudinais , Farmacêuticos , Desenvolvimento de Pessoal/métodos , EnsinoRESUMO
Viral infections of the central nervous system (CNS) often cause disease in an age-dependent manner, with greater neuropathology during the fetal and neonatal periods. Transgenic CD46+ mice model these age-dependent outcomes through a measles virus infection of CNS neurons. Adult CD46+ mice control viral spread and survive the infection in an interferon gamma (IFNγ)-dependent manner, whereas neonatal CD46+ mice succumb despite similar IFNγ expression in the brain. Thus, we hypothesized that IFNγ signaling in the adult brain may be more robust, potentially due to greater basal expression of IFNγ signaling proteins. To test this hypothesis, we evaluated the expression of canonical IFNγ signaling proteins in the neonatal and adult brain, including the IFNγ receptor, Janus kinase (JAK) 1/2, and signal transducer and activator of transcription-1 (STAT1) in the absence of infection. We also analyzed the expression and activation of STAT1 and IFNγ-stimulated genes during MV infection. We found that neonatal brains have equivalent or greater JAK/STAT1 expression in the hippocampus and the cerebellum than adults. IFNγ receptor expression varied by cell type in the brain but was widely expressed on neuronal and glial cells. During MV infection, increased STAT1 expression and activation correlated with viral load in the hippocampus regardless of age, but not in the cerebellum where viral load was consistently undetectable in adults. These results suggest the neonatal brain is capable of initiating IFNγ signaling during a viral infection, but that downstream STAT1 activation is insufficient to limit viral spread.
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Encéfalo/metabolismo , Encéfalo/virologia , Interferon gama/metabolismo , Sarampo/metabolismo , Transdução de Sinais/fisiologia , Carga Viral/fisiologia , Fatores Etários , Animais , Animais Recém-Nascidos , Encéfalo/imunologia , Chlorocebus aethiops , Feminino , Interferon gama/imunologia , Masculino , Sarampo/imunologia , Camundongos , Camundongos Transgênicos , Fator de Transcrição STAT1/imunologia , Fator de Transcrição STAT1/metabolismo , Células VeroRESUMO
Viral infections of the central nervous system are accompanied by the expression of cytokines and chemokines that can be critical for the control of viral replication in the brain. The outcomes of cytokine/chemokine signaling in neural cells vary widely, with cell-specific effects on cellular activity, proliferation, and survival. Neural stem/progenitor cells (NSPCs) are often altered during viral infections, through direct infection by the virus or by the influence of immune cell activity or cytokine/chemokine signaling. However, it has been challenging to dissect the contribution of the virus and specific inflammatory mediators during an infection. In addition to initiating an antiviral program in infected NSPCs, cytokines/chemokines can induce multiple changes in NSPC behavior that can perturb NSPC numbers, differentiation into other neural cells, and migration to sites of injury, and ultimately brain development and repair. The focus of this review was to dissect the effects of common antiviral cytokines and chemokines on NSPC activity, and to consider the subsequent pathological consequences for the host from changes in NSPC function.
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Viroses do Sistema Nervoso Central/imunologia , Quimiocinas/imunologia , Citocinas/imunologia , Células-Tronco Neurais/imunologia , Transdução de Sinais , Animais , Encéfalo/imunologia , Células Cultivadas , Humanos , Inflamação , Camundongos , Replicação Viral/imunologiaRESUMO
Neonates are highly susceptible to viral infections in the periphery, potentially due to deviant cytokine responses. Here, we investigated the role of interferon-gamma (IFNγ), a key anti-viral in the neonatal brain. We found that (i) IFNγ, which is critical for viral control and survival in adults, delays mortality in neonates, (ii) IFNγ limits infiltration of macrophages, neutrophils, and T cells in the neonatal brain, (iii) neonates and adults differentially express pathogen recognition receptors and Type I interferons in response to the infection, (iv) both neonates and adults express IFNγ and other Th1-related factors, but expression of many cytokines/chemokines and IFNγ-responsive genes is age-dependent, and (v) administration of IFNγ extends survival and reduces CD4 T cell infiltration in the neonatal brain. Our findings suggest age-dependent expression of cytokine/chemokine profiles in the brain and distinct dynamic interplays between lymphocyte populations and cytokines/chemokines in MV-infected neonates.
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Encéfalo/imunologia , Encéfalo/virologia , Interferon gama/imunologia , Sarampo/imunologia , Neurônios/imunologia , Neurônios/virologia , Animais , Animais Recém-Nascidos , Humanos , Sarampo/congênito , Vírus do Sarampo/imunologia , Camundongos , Camundongos Transgênicos , Células Th1/imunologiaRESUMO
Neuronal damage in human immunodeficiency virus type 1 (HIV-1) infection in the brain is thought to occur at least in part through NMDA receptor (NMDAR) excitation initiated by soluble neurotoxins from HIV-infected brain macrophages. Furthermore, brain regions enriched in NMDAR-2A (NR2A) and NMDAR-2B (NR2B) subunits, such as the hippocampus, are particularly vulnerable. Using cultured rat hippocampal cells and HIV-1-infected human monocyte-derived macrophages (HIV/MDM), we examined the role of NR2A and NR2B in HIV/MDM-induced hippocampal neuronal death. We used the primary HIV-1 strain Jago derived from the CSF of an individual with HIV-associated dementia and that robustly replicates in MDM. We found the following: (1) hippocampal neuronal susceptibility to HIV/MDM excitotoxins varies according to the developmental expression patterns of NR2A and NR2B; (2) NMDAR activation by HIV/MDM results in neuronal calpain activation, which results in neuronal death; and (3) selective antagonists of homomeric NR2B/NR2B- and heteromeric NR2A/NR2B-containing NMDARs, as well as an inhibitor of calpain activity, afford neuroprotection against HIV/MDM. These studies establish a clear link between macrophage HIV infection, neuronal NR2A and NR2B activation, and calpain-mediated hippocampal neuronal death. They further suggest a dominant role for NR2A and NR2B in determining neuronal susceptibility in HIV-infected brain. Antagonists of NR2A and NR2B subunits as well as inhibitors of calpain activation offer attractive neuroprotective approaches against HIV in both developing and mature brain.
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HIV-1/patogenicidade , Macrófagos/metabolismo , Macrófagos/virologia , Receptores de N-Metil-D-Aspartato/fisiologia , Animais , Fármacos Anti-HIV/farmacologia , Calpaína/antagonistas & inibidores , Calpaína/metabolismo , Células Cultivadas , Inibidores de Cisteína Proteinase/farmacologia , Antagonistas de Aminoácidos Excitatórios/farmacologia , HIV-1/efeitos dos fármacos , Hipocampo/efeitos dos fármacos , Hipocampo/metabolismo , Hipocampo/virologia , Humanos , Macrófagos/efeitos dos fármacos , Fármacos Neuroprotetores/farmacologia , Ratos , Ratos Sprague-Dawley , Receptores de N-Metil-D-Aspartato/antagonistas & inibidores , Receptores de N-Metil-D-Aspartato/metabolismoRESUMO
With the alarming rise of antibiotic resistance, clinical professionals are called upon to manage antibiotic therapies using the most relevant and recent clinical and laboratory data. To this end, antimicrobial stewardship (AMS) programs aim to reduce unnecessary or suboptimal use of antibiotics while maximizing outcomes for the patient. For AMS programs to succeed, the active participation of clinical professionals at all levels of patient care is required. Although programs exist to train established clinicians in AMS, there is a paucity of literature on how and when to integrate AMS concepts and skills in pre-clinical and clinical coursework. Here, we discuss the crucial microbiology concepts and proficiencies that are necessary for building and supporting an AMS program. We provide recommendations for key points to include in clinical curricula in order to develop the necessary microbiology interpretation skills to participate in AMS. The influence of AMS programs on local organism susceptibility patterns is emphasized. The importance of antibiograms, rapid diagnostic testing and the practical interpretations of microbiology laboratory reporting are discussed in regard to prioritization in clinical curricula. We also review the current literature on instructional strategies for introducing AMS into clinical programs, and propose concepts that should be included in didactic coursework in order to provide a foundation for AMS education.
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Gestão de Antimicrobianos , Resistência Microbiana a Medicamentos , Educação Médica , Educação em Farmácia , Pessoal de Saúde/educação , Microbiologia/educação , Antibacterianos , HumanosRESUMO
Interest in global health education within the pharmacy curriculum has increased significantly in recent years. However, discussion of different models and methods to evaluate course structures are limited. The overall objective was to (1) describe the structure of our global health elective for pharmacy students, and (2) assess educational outcomes related to perceived/formal knowledge and attitudes associated with global health. Our elective was designed using a competency-centered approach to global health education, incorporating reflection, projects, service and game-learning. In addition to course assessments, a pre-post survey questionnaire assessing attitudes, knowledge perception, formalized knowledge and opinions was utilized. Overall, students demonstrated appropriate performance on course assessments, temporally improving throughout longitudinal projects. The survey demonstrated significant increases in knowledge perception as a result of the course; however, no change in formalized knowledge was evident through the survey assessment. Additionally, the incorporation of game-learning into the course was well received by students. Future iterations of the course will focus on utilization of different assessment methods to meet learning outcomes.
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Interferon-gamma (IFNγ), a pleiotropic cytokine, is expressed in diverse neurodegenerative and neuroinflammatory conditions. Its protective mechanisms are well documented during viral infections in the brain, where IFNγ mediates non-cytolytic viral control in infected neurons. However, IFNγ also plays both protective and pathological roles in other central nervous system (CNS) diseases. Of the many neural cells that respond to IFNγ, neural stem/progenitor cells (NSPCs), the only pluripotent cells in the developing and adult brain, are often altered during CNS insults. Recent studies highlight the complex effects of IFNγ on NSPC activity in neurodegenerative diseases. However, the mechanisms that mediate these effects, and the eventual outcomes for the host, are still being explored. Here, we review the effects of IFNγ on NSPC activity during different pathological insults. An improved understanding of the role of IFNγ would provide insight into the impact of immune responses on the progression and resolution of neurodegenerative diseases.