RESUMO
Extensive research provides evidence that neuroinflammation underlies numerous brain disorders. However, the molecular mechanisms by which inflammatory mediators determine synaptic and cognitive dysfunction occurring in neurodegenerative diseases (e.g., Alzheimer's disease) are far from being fully understood. Here we investigated the role of interleukin 1ß (IL-1ß), and the molecular cascade downstream the activation of its receptor, to the synaptic dysfunction occurring in the mouse model of multiple Herpes simplex virus type-1 (HSV-1) reactivations within the brain. These mice are characterized by neuroinflammation and memory deficits associated with a progressive accumulation of neurodegenerative hallmarks (e.g., amyloid-ß protein and tau hyperphosphorylation). Here we show that mice undergone two HSV-1 reactivations in the brain exhibited increased levels of IL-1ß along with significant alterations of: (1) cognitive performances; (2) hippocampal long-term potentiation; (3) expression synaptic-related genes and pre- and post-synaptic proteins; (4) dendritic spine density and morphology. These effects correlated with activation of the epigenetic repressor MeCP2 that, in association with HDAC4, affected the expression of synaptic plasticity-related genes. Specifically, in response to HSV-1 infection, HDAC4 accumulated in the nucleus and promoted MeCP2 SUMOylation that is a post-translational modification critically affecting the repressive activity of MeCP2. The blockade of IL-1 receptors by the specific antagonist Anakinra prevented the MeCP2 increase and the consequent downregulation of gene expression along with rescuing structural and functional indices of neurodegeneration. Collectively, our findings provide novel mechanistic evidence on the role played by HSV-1-activated IL-1ß signaling pathways in synaptic deficits leading to cognitive impairment.
Assuntos
Doença de Alzheimer , Herpes Simples , Herpesvirus Humano 1 , Camundongos , Animais , Herpesvirus Humano 1/metabolismo , Interleucina-1beta/genética , Interleucina-1beta/metabolismo , Doenças Neuroinflamatórias , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Herpes Simples/complicações , Transtornos da Memória/genética , Plasticidade Neuronal/fisiologia , Epigênese Genética , Hipocampo/metabolismo , Modelos Animais de Doenças , Proteína 2 de Ligação a Metil-CpG/genética , Proteína 2 de Ligação a Metil-CpG/metabolismoRESUMO
Herpes simplex virus type-1 (HSV-1) and John Cunningham polyomavirus (JCPyV) are widely distributed DNA viruses causing mainly asymptomatic infection, but also mild to very severe diseases, especially when these viruses reach the brain. Some drugs have been developed to inhibit HSV-1 replication in host cells, but their prolonged use may induce resistance phenomena. In contrast, to date, there is no cure for JCPyV. The search for alternative drugs that can reduce viral infections without undermining the host cell is moving toward antimicrobial peptides (AMPs) of natural occurrence. These include amphibian AMPs belonging to the temporin family. Herein, we focus on temporin G (TG), showing that it strongly affects HSV-1 replication by acting either during the earliest stages of its life cycle or directly on the virion. Computational studies have revealed the ability of TG to interact with HSV-1 glycoprotein B. We also found that TG reduced JCPyV infection, probably affecting both the earliest phases of its life cycle and the viral particle, likely through an interaction with the viral capsid protein VP1. Overall, our results are promising for the development of short naturally occurring peptides as antiviral agents used to counteract diseases related to HSV-1 and JCPyV.
Assuntos
Herpesvirus Humano 1 , Anfíbios , Animais , Peptídeos Catiônicos Antimicrobianos/farmacologia , Peptídeos Antimicrobianos , Herpesvirus Humano 1/fisiologia , Replicação ViralRESUMO
Astrocytes provide metabolic support for neurons and modulate their functions by releasing a plethora of neuroactive molecules diffusing to neighboring cells. Here we report that astrocytes also play a role in cortical neurons' vulnerability to Herpes simplex virus type-1 (HSV-1) infection through the release of extracellular ATP. We found that the interaction of HSV-1 with heparan sulfate proteoglycans expressed on the plasma membrane of astrocytes triggered phospholipase C-mediated IP3 -dependent intracellular Ca2+ transients causing extracellular release of ATP. ATP binds membrane purinergic P2 receptors (P2Rs) of both neurons and astrocytes causing an increase in intracellular Ca2+ concentration that activates the Glycogen Synthase Kinase (GSK)-3ß, whose action is necessary for HSV-1 entry/replication in these cells. Indeed, in co-cultures of neurons and astrocytes HSV-1-infected neurons were only found in proximity of infected astrocytes releasing ATP, whereas in the presence of fluorocitrate, an inhibitor of astrocyte metabolism, switching-off the HSV-1-induced ATP release, very few neurons were infected. The addition of exogenous ATP, mimicking that released by astrocytes after HSV-1 challenge, restored the ability of HSV-1 to infect neurons co-cultured with metabolically-inhibited astrocytes. The ATP-activated, P2R-mediated, and GSK-3-dependent molecular pathway underlying HSV-1 infection is likely shared by neurons and astrocytes, given that the blockade of either P2Rs or GSK-3 activation inhibited infection of both cell types. These results add a new layer of information to our understanding of the critical role played by astrocytes in regulating neuronal functions and their response to noxious stimuli including microbial agents via Ca2+ -dependent release of neuroactive molecules.
Assuntos
Herpes Simples , Herpesvirus Humano 1 , Trifosfato de Adenosina , Astrócitos , Células Cultivadas , Quinase 3 da Glicogênio Sintase , Humanos , Neurônios , Receptores Purinérgicos P2RESUMO
Herpes simplex virus type 1 (HSV-1) is a DNA neurotropic virus, usually establishing latent infections in the trigeminal ganglia followed by periodic reactivations. Although numerous findings suggested potential links between HSV-1 and Alzheimer's disease (AD), a causal relation has not been demonstrated yet. Hence, we set up a model of recurrent HSV-1 infection in mice undergoing repeated cycles of viral reactivation. By virological and molecular analyses we found: i) HSV-1 spreading and replication in different brain regions after thermal stress-induced virus reactivations; ii) accumulation of AD hallmarks including amyloid-ß protein, tau hyperphosphorylation, and neuroinflammation markers (astrogliosis, IL-1ß and IL-6). Remarkably, the progressive accumulation of AD molecular biomarkers in neocortex and hippocampus of HSV-1 infected mice, triggered by repeated virus reactivations, correlated with increasing cognitive deficits becoming irreversible after seven cycles of reactivation. Collectively, our findings provide evidence that mild and recurrent HSV-1 infections in the central nervous system produce an AD-like phenotype and suggest that they are a risk factor for AD.
Assuntos
Transtornos Cognitivos/metabolismo , Transtornos Cognitivos/virologia , Herpesvirus Humano 1/patogenicidade , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides , Animais , Encéfalo/virologia , Cognição/fisiologia , Transtornos Cognitivos/etiologia , Disfunção Cognitiva/etiologia , Disfunção Cognitiva/metabolismo , Disfunção Cognitiva/virologia , Modelos Animais de Doenças , Feminino , Herpesvirus Humano 1/metabolismo , Camundongos , Camundongos Endogâmicos BALB C , Doenças Neurodegenerativas/etiologia , Doenças Neurodegenerativas/virologia , Gânglio Trigeminal/virologia , Ativação Viral/fisiologia , Replicação Viral/fisiologiaRESUMO
Herpes simplex virus 1 (HSV-1) is a widespread neurotropic virus establishing a life-long latent infection in neurons with periodic reactivations. Recent studies linked HSV-1 to neurodegenerative processes related to age-related disorders such as Alzheimer's disease. Here, we explored whether recurrent HSV-1 infection might accelerate aging in neurons, focusing on peculiar marks of aged cells, such as the increase in histone H4 lysine (K) 16 acetylation (ac) (H4K16ac); the decrease of H3K56ac, and the modified expression of Sin3/HDAC1 and HIRA proteins. By exploiting both in vitro and in vivo models of recurrent HSV-1 infection, we found a significant increase in H4K16ac, Sin3, and HDAC1 levels, suggesting that the neuronal response to virus latency and reactivation includes the upregulation of these aging markers. On the contrary, we found a significant decrease in H3K56ac that was specifically linked to viral reactivation and apparently not related to aging-related markers. A complex modulation of HIRA expression and localization was found in the brain from HSV-1 infected mice suggesting a specific role of this protein in viral latency and reactivation. Overall, our results pointed out novel molecular mechanisms through which recurrent HSV-1 infection may affect neuronal aging, likely contributing to neurodegeneration.
Assuntos
Senescência Celular , Herpes Simples/patologia , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Modelos Biológicos , Neurônios/patologia , Neurônios/virologia , Acetilação , Animais , Proteínas de Ciclo Celular/metabolismo , Modelos Animais de Doenças , Chaperonas de Histonas/metabolismo , Histona Desacetilase 1/metabolismo , Histonas/metabolismo , Lisina/metabolismo , Ratos Wistar , Recidiva , Complexo Correpressor Histona Desacetilase e Sin3/metabolismo , Fatores de Transcrição/metabolismo , Latência ViralRESUMO
Coronavirus disease 2019 (COVID-19), first reported in Wuhan, the capital of Hubei, China, has been associated to a novel coronavirus, the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). In March 2020, the World Health Organization declared the SARS-CoV-2 infection a global pandemic. Soon after, the number of cases soared dramatically, spreading across China and worldwide. Italy has had 12,462 confirmed cases according to the Italian National Institute of Health (ISS) as of March 11, and after the "lockdown" of the entire territory, by May 4, 209,254 cases of COVID-19 and 26,892 associated deaths have been reported. We performed a review to describe, in particular, the origin and the diffusion of COVID-19 in Italy, underlying how the geographical circulation has been heterogeneous and the importance of pathophysiology in the involvement of cardiovascular and neurological clinical manifestations.
Assuntos
Doenças Cardiovasculares/epidemiologia , Infecções por Coronavirus/epidemiologia , Síndrome da Liberação de Citocina/epidemiologia , Doenças do Sistema Nervoso/epidemiologia , Pandemias , Pneumonia Viral/epidemiologia , Síndrome Respiratória Aguda Grave/epidemiologia , Fatores Etários , Betacoronavirus/efeitos dos fármacos , Betacoronavirus/imunologia , Betacoronavirus/patogenicidade , COVID-19 , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/mortalidade , Doenças Cardiovasculares/virologia , Infecções por Coronavirus/diagnóstico , Infecções por Coronavirus/mortalidade , Infecções por Coronavirus/transmissão , Síndrome da Liberação de Citocina/diagnóstico , Síndrome da Liberação de Citocina/mortalidade , Síndrome da Liberação de Citocina/virologia , Geografia , Humanos , Itália/epidemiologia , Doenças do Sistema Nervoso/diagnóstico , Doenças do Sistema Nervoso/mortalidade , Doenças do Sistema Nervoso/virologia , Pneumonia Viral/diagnóstico , Pneumonia Viral/mortalidade , Pneumonia Viral/transmissão , Prevalência , SARS-CoV-2 , Síndrome Respiratória Aguda Grave/diagnóstico , Síndrome Respiratória Aguda Grave/mortalidade , Síndrome Respiratória Aguda Grave/transmissão , Fatores Sexuais , Análise de SobrevidaRESUMO
We previously reported that Herpes simplex virus type-1 (HSV-1) infection of cultured neurons triggered intracellular accumulation of amyloid-ß protein (Aß) markedly impinging on neuronal functions. Here, we demonstrated that HSV-1 affects in vitro and in vivo adult hippocampal neurogenesis by reducing neural stem/progenitor cell (NSC) proliferation and their neuronal differentiation via intracellular Aß accumulation. Specifically, cultured NSCs were more permissive for HSV-1 replication than mature neurons and, once infected, they exhibited reduced proliferation (assessed by 5'-bromo-deoxyuridine incorporation, Ki67 immunoreactivity, and Sox2 mRNA expression) and impaired neuronal differentiation in favor of glial phenotype (evaluated by immunoreactivity for the neuronal marker MAP2, the glial marker glial fibrillary astrocyte protein, and the expression of the proneuronal genes Mash1 and NeuroD1). Similarly, impaired adult neurogenesis was observed in the subgranular zone of hippocampal dentate gyrus of an in vivo model of recurrent HSV-1 infections, that we recently set up and characterized, with respect to mock-infected mice. The effects of HSV-1 on neurogenesis did not depend on cell death and were due to Aß accumulation in infected NSCs. Indeed, they were: (a) reverted, in vitro, by the presence of either ß/γ-secretase inhibitors preventing Aß production or the specific 4G8 antibody counteracting the action of intracellular Aß; (b) not detectable, in vivo, in HSV-1-infected amyloid precursor protein knockout mice, unable to produce and accumulate Aß. Given the critical role played by adult neurogenesis in hippocampal-dependent memory and learning, our results suggest that multiple virus reactivations in the brain may contribute to Alzheimer's disease phenotype by also targeting NSCs. Stem Cells 2019;37:1467-1480.
Assuntos
Peptídeos beta-Amiloides/metabolismo , Herpesvirus Humano 1/patogenicidade , Hipocampo/metabolismo , Hipocampo/virologia , Peptídeos beta-Amiloides/genética , Precursor de Proteína beta-Amiloide/genética , Precursor de Proteína beta-Amiloide/metabolismo , Animais , Western Blotting , Células Cultivadas , Imuno-Histoquímica , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Células-Tronco Neurais/citologia , Células-Tronco Neurais/metabolismo , Neurogênese/genética , Neurogênese/fisiologia , Reação em Cadeia da Polimerase Via Transcriptase ReversaRESUMO
In the last decade essential oils have attracted scientists with a constant increase rate of more than 7% as witnessed by almost 5000 articles. Among the prominent studies essential oils are investigated as antibacterial agents alone or in combination with known drugs. Minor studies involved essential oil inspection as potential anticancer and antiviral natural remedies. In line with the authors previous reports the investigation of an in-house library of extracted essential oils as a potential blocker of HSV-1 infection is reported herein. A subset of essential oils was experimentally tested in an in vitro model of HSV-1 infection and the determined IC50s and CC50s values were used in conjunction with the results obtained by gas-chromatography/mass spectrometry chemical analysis to derive machine learning based classification models trained with the partial least square discriminant analysis algorithm. The internally validated models were thus applied on untested essential oils to assess their effective predictive ability in selecting both active and low toxic samples. Five essential oils were selected among a list of 52 and readily assayed for IC50 and CC50 determination. Interestingly, four out of the five selected samples, compared with the potencies of the training set, returned to be highly active and endowed with low toxicity. In particular, sample CJM1 from Calaminta nepeta was the most potent tested essential oil with the highest selectivity index (IC50 = 0.063 mg/mL, SI > 47.5). In conclusion, it was herein demonstrated how multidisciplinary applications involving machine learning could represent a valuable tool in predicting the bioactivity of complex mixtures and in the near future to enable the design of blended essential oil possibly endowed with higher potency and lower toxicity.
Assuntos
Antivirais/farmacologia , Herpesvirus Humano 1/efeitos dos fármacos , Lamiales/química , Óleos Voláteis/farmacologia , Óleos de Plantas/farmacologia , Aprendizado de Máquina Supervisionado/estatística & dados numéricos , Animais , Antivirais/isolamento & purificação , Chlorocebus aethiops , Cromatografia Gasosa-Espectrometria de Massas , Herpesvirus Humano 1/crescimento & desenvolvimento , Humanos , Testes de Sensibilidade Microbiana , Óleos Voláteis/isolamento & purificação , Óleos de Plantas/isolamento & purificação , Relação Estrutura-Atividade , Células VeroRESUMO
Several data indicate that neuronal infection with herpes simplex virus type 1 (HSV-1) causes biochemical alterations reminiscent of Alzheimer's disease (AD) phenotype. They include accumulation of amyloid-ß (Aß), which originates from the cleavage of amyloid precursor protein (APP), and hyperphosphorylation of tau protein, which leads to neurofibrillary tangle deposition. HSV-1 infection triggers APP processing and drives the production of several fragments including APP intracellular domain (AICD) that exerts transactivating properties. Herein, we analyzed the production and intracellular localization of AICD following HSV-1 infection in neurons. We also checked whether AICD induced the transcription of two target genes, neprilysin (nep) and glycogen synthase kinase 3ß (gsk3ß), whose products play a role in Aß clearance and tau phosphorylation, respectively. Our data indicate that HSV-1 led to the accumulation and nuclear translocation of AICD in neurons. Moreover, results from chromatin immunoprecipitation assay showed that AICD binds the promoter region of both nep and gsk3ß. Time course analysis of NEP and GSK3ß expression at both mRNA and protein levels demonstrated that they are differently modulated during infection. NEP expression and enzymatic activity were initially stimulated but, with the progression of infection, they were down-regulated. In contrast, GSK3ß expression remained nearly unchanged, but the analysis of its phosphorylation suggests that it was inactivated only at later stages of HSV-1 infection. Thus, our data demonstrate that HSV-1 infection induces early upstream events in the cell that may eventually lead to Aß deposition and tau hyperphosphorylation and further suggest HSV-1 as a possible risk factor for AD.
Assuntos
Doença de Alzheimer/virologia , Precursor de Proteína beta-Amiloide/metabolismo , Herpes Simples/metabolismo , Neurônios/metabolismo , Neurônios/virologia , Doença de Alzheimer/metabolismo , Animais , Western Blotting , Células Cultivadas , Córtex Cerebral , Imunoprecipitação da Cromatina , Quinase 3 da Glicogênio Sintase/biossíntese , Glicogênio Sintase Quinase 3 beta , Herpesvirus Humano 1 , Imuno-Histoquímica , Imunoprecipitação , Neprilisina/biossíntese , Ratos , Ratos Wistar , Reação em Cadeia da Polimerase em Tempo RealRESUMO
Accumulation of DNA damage and deficiency in DNA repair potentially contribute to the progressive neuronal loss in neurodegenerative disorders, including Alzheimer disease (AD). In multicellular eukaryotes, double strand breaks (DSBs), the most lethal form of DNA damage, are mainly repaired by the nonhomologous end joining pathway, which relies on DNA-PK complex activity. Both the presence of DSBs and a decreased end joining activity have been reported in AD brains, but the molecular player causing DNA repair dysfunction is still undetermined. ß-Amyloid (Aß), a potential proximate effector of neurotoxicity in AD, might exert cytotoxic effects by reactive oxygen species generation and oxidative stress induction, which may then cause DNA damage. Here, we show that in PC12 cells sublethal concentrations of aggregated Aß(25-35) inhibit DNA-PK kinase activity, compromising DSB repair and sensitizing cells to nonlethal oxidative injury. The inhibition of DNA-PK activity is associated with down-regulation of the catalytic subunit DNA-PK (DNA-PKcs) protein levels, caused by oxidative stress and reversed by antioxidant treatment. Moreover, we show that sublethal doses of Aß(1-42) oligomers enter the nucleus of PC12 cells, accumulate as insoluble oligomeric species, and reduce DNA-PK kinase activity, although in the absence of oxidative stress. Overall, these findings suggest that Aß mediates inhibition of the DNA-PK-dependent nonhomologous end joining pathway contributing to the accumulation of DSBs that, if not efficiently repaired, may lead to the neuronal loss observed in AD.
Assuntos
Peptídeos beta-Amiloides/farmacologia , Quebras de DNA de Cadeia Dupla/efeitos dos fármacos , Reparo do DNA/efeitos dos fármacos , Proteína Quinase Ativada por DNA/metabolismo , Proteínas Nucleares/metabolismo , Estresse Oxidativo , Multimerização Proteica , Doença de Alzheimer/genética , Doença de Alzheimer/metabolismo , Animais , Proteína Quinase Ativada por DNA/genética , Humanos , Proteínas Nucleares/genética , Células PC12 , RatosRESUMO
Resveratrol (RSV) is a natural stilbene polyphenolic compound found in several plant species. It is characterized by antioxidant properties, and its role in controlling viral replication has been demonstrated for different viral infections. Despite its promising antiviral properties, RSV biological activity is limited by its low bioavailability and high metabolic rate. In this study, we optimized its structure by synthesizing new RSV derivatives that maintained the phenolic scaffold and contained different substitution patterns and evaluated their potential anti-influenza virus activity. The results showed that viral protein synthesis decreased 24 h post infection; particularly, the nitro-containing compounds strongly reduced viral replication. The molecules did not exert their antioxidant properties during infection; in fact, they were not able to rescue the virus-induced drop in GSH content or improve the antioxidant response mediated by the Nrf2 transcription factor and G6PD enzyme. Similar to what has already been reported for RSV, they interfered with the nuclear-cytoplasmic traffic of viral nucleoprotein, probably inhibiting cellular kinases involved in the regulation of specific steps of the virus life cycle. Overall, the data indicate that more lipophilic RSV derivatives have improved antiviral efficacy compared with RSV and open the way for new cell-targeted antiviral strategies.
RESUMO
Herpes simplex virus-1 (HSV-1) is a ubiquitous DNA virus able to establish a life-long latent infection in host sensory ganglia. Following periodic reactivations, the neovirions usually target the site of primary infection causing recurrent diseases in susceptible individuals. However, reactivated HSV-1 may also reach the brain resulting in severe herpetic encephalitis or in asymptomatic infections. These have been reportedly linked to neurodegenerative disorders, such as Alzheimer's disease (AD), suggesting antiviral preventive or/therapeutic treatments as possible strategies to counteract AD onset and progression. Here, we provide an overview of the AD-like mechanisms driven by HSV-1-infection in neurons and discuss the ongoing trials repurposing anti-herpetic drugs to treat AD as well as preventive strategies aimed at blocking virus infection.
Assuntos
Doença de Alzheimer , Herpes Simples , Herpesvirus Humano 1 , Doença de Alzheimer/tratamento farmacológico , Doença de Alzheimer/prevenção & controle , Encéfalo , Herpes Simples/tratamento farmacológico , Herpes Simples/prevenção & controle , Herpesvirus Humano 1/genética , Humanos , NeurôniosRESUMO
Influenza virus infection induces oxidative stress in host cells by decreasing the intracellular content of glutathione (GSH) and increasing reactive oxygen species (ROS) level. Glucose-6-phosphate dehydrogenase (G6PD) is responsible for the production of reducing equivalents of nicotinamide adenine dinucleotide phosphate (NADPH) that is used to regenerate the reduced form of GSH, thus restoring redox homeostasis. Cells deficient in G6PD display elevated levels of ROS and an increased susceptibility to viral infection, although the consequences of G6PD modulation during viral infection remain to be elucidated. In this study, we demonstrated that influenza virus infection decreases G6PD expression and activity, resulting in an increase in oxidative stress and virus replication. Moreover, the down regulation of G6PD correlated with a decrease in the expression of nuclear factor erythroid 2-related factor 2 (NRF2), a key transcription factor that regulates the expression of the antioxidant response gene network. Also down-regulated in influenza virus infected cells was sirtuin 2 (SIRT2), a NADPH-dependent deacetylase involved in the regulation of G6PD activity. Acetylation of G6PD increased during influenza virus infection in a manner that was strictly dependent on SIRT2 expression. Furthermore, the use of a pharmacological activator of SIRT2 rescued GSH production and NRF2 expression, leading to decreased influenza virus replication. Overall, these data identify a novel strategy used by influenza virus to induce oxidative stress and to favor its replication in host cells. These observations furthermore suggest that manipulation of metabolic and oxidative stress pathways could define new therapeutic strategies to interfere with influenza virus infection.
Assuntos
Glucosefosfato Desidrogenase , Orthomyxoviridae , Glucosefosfato Desidrogenase/genética , Glucosefosfato Desidrogenase/metabolismo , Glutationa/metabolismo , Estresse Oxidativo , Espécies Reativas de OxigênioRESUMO
Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the etiologic agent of the COVID-19 pandemic. Although other diagnostic methods have been introduced, detection of viral genes on oro- and nasopharyngeal swabs by reverse-transcription real time-PCR (rRT-PCR) assays is still the gold standard. Efficient viral RNA extraction is a prerequisite for downstream performance of rRT-PCR assays. Currently, several automatic methods that include RNA extraction are available. However, due to the growing demand, a shortage in kit supplies could be experienced in several labs. For these reasons, the use of different commercial or in-house protocols for RNA extraction may increase the possibility to analyze high number of samples. Herein, we compared the efficiency of RNA extraction of three different commercial kits and an in-house extraction protocol using synthetic ssRNA standards of SARS-CoV-2 as well as in oro-nasopharyngeal swabs from six COVID-19-positive patients. It was concluded that tested commercial kits can be used with some modifications for the detection of the SARS-CoV-2 genome by rRT-PCR approaches, although with some differences in RNA yields. Conversely, EXTRAzol reagent was the less efficient due to the phase separation principle at the basis of RNA extraction. Overall, this study offers alternative suitable methods to manually extract RNA that can be taken into account for SARS-CoV-2 detection.
Assuntos
Teste de Ácido Nucleico para COVID-19/métodos , COVID-19/diagnóstico , RNA Viral/isolamento & purificação , SARS-CoV-2/isolamento & purificação , Testes Diagnósticos de Rotina , Genes Virais/genética , Humanos , Limite de Detecção , Faringe/virologia , RNA Viral/análise , RNA Viral/genética , Reprodutibilidade dos Testes , SARS-CoV-2/genéticaRESUMO
The resinous exudate produced by Commiphora myrrha (Nees) Engl. is commonly known as true myrrh and has been used since antiquity for several medicinal applications. Hundreds of metabolites have been identified in the volatile component of myrrh so far, mainly sesquiterpenes. Although several efforts have been devoted to identifying these sesquiterpenes, the phytochemical analyses have been performed by gas-chromatography/mass spectrometry (GC-MS) where the high temperature employed can promote degradation of the components. In this work, we report the extraction of C. myrrha by supercritical CO2, an extraction method known for the mild extraction conditions that allow avoiding undesired chemical reactions during the process. In addition, the analyses of myrrh oil and of its metabolites were performed by HPLC and GC-MS. Moreover, we evaluated the antiviral activity against influenza A virus of the myrrh extracts, that was possible to appreciate after the addition of vitamin E acetate (α-tocopheryl acetate) to the extract. Further, the single main bioactive components of the oil of C. myrrha commercially available were tested. Interestingly, we found that both furanodienone and curzerene affect viral replication by acting on different steps of the virus life cycle.
RESUMO
Protein phosphorylation is the main signaling system known to trigger synaptic changes underlying long-term potentiation (LTP). The timing of these phosphorylations plays an essential role to maintain the potentiated state of synapses. However, in mice a simultaneous analysis of phosphorylated proteins during early-LTP (E-LTP) has not been thoroughly carried out. Here we described phosphorylation changes of alphaCaMKII, ERK1/2, PKB/Akt and CREB at different times after E-LTP induced at Schaffer collateral/commissural fiber-CA1 synapses by 1 s 100 Hz tetanic stimulation in mouse hippocampal slices. We found that phosphorylation levels of all the molecules examined rapidly increased after tetanisation and remained above the basal level up to 30 min. Notably, we observed a sustained increment in the phosphorylation level of Akt at Ser473, whereas the phosphorylation level of Akt at Thr308 was unchanged. Unexpectedly, we also detected a marked increase of CREB target genes expression levels, c-fos, Egr-1 and exon-III containing BDNF transcripts. Our findings, besides providing a detailed timing of phosphorylation of the major kinases involved in E-LTP in mice, revealed that a modest LTP induction paradigm specifically triggers CREB-mediated gene expression.
Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/metabolismo , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Hipocampo/fisiologia , Potenciação de Longa Duração/fisiologia , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Proteína Quinase 3 Ativada por Mitógeno/metabolismo , Proteínas Proto-Oncogênicas c-akt/metabolismo , Sinapses/fisiologia , Animais , Fator Neurotrófico Derivado do Encéfalo/genética , Proteína 1 de Resposta de Crescimento Precoce/genética , Estimulação Elétrica , Genes fos/fisiologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Fosforilação , Serina/metabolismoRESUMO
Herpes simplex virus-1 (HSV-1) establishes latency preferentially in sensory neurons of peripheral ganglia. A variety of stresses can induce recurrent reactivations of the virus, which spreads and then actively replicates to the site of primary infection (usually the lips or eyes). Viral particles produced following reactivation can also reach the brain, causing a rare but severe form of diffuse acute infection, namely herpes simplex encephalitis. Most of the time, this infection is clinically asymptomatic. However, it was recently correlated with the production and accumulation of neuropathological biomarkers of Alzheimer's disease. In this review we discuss the different cellular and molecular mechanisms underlying the acute and long-term damage caused by HSV-1 infection in the brain.
Assuntos
Encefalopatias/virologia , Herpes Simples/virologia , Herpesvirus Humano 1/fisiologia , Animais , Encéfalo/virologia , Herpesvirus Humano 1/genética , HumanosRESUMO
Compelling evidence supports the role of oxidative stress in Alzheimer's disease (AD) pathophysiology. Interestingly, Herpes simplex virus-1 (HSV-1), a neurotropic virus that establishes a lifelong latent infection in the trigeminal ganglion followed by periodic reactivations, has been reportedly linked both to AD and to oxidative stress conditions. Herein, we analyzed, through biochemical and redox proteomic approaches, the mouse model of recurrent HSV-1 infection we previously set up, to investigate whether multiple virus reactivations induced oxidative stress in the mouse brain and affected protein function and related intracellular pathways. Following multiple HSV-1 reactivations, we found in mouse brains increased levels of oxidative stress hallmarks, including 4-hydroxynonenal (HNE), and 13 HNE-modified proteins whose levels were found significantly altered in the cortex of HSV-1-infected mice compared to controls. We focused on two proteins previously linked to AD pathogenesis, i.e., glucose-regulated protein 78 (GRP78) and collapsin response-mediated protein 2 (CRMP2), which are involved in the unfolded protein response (UPR) and in microtubule stabilization, respectively. We found that recurrent HSV-1 infection disables GRP78 function and activates the UPR, whereas it prevents CRMP2 function in mouse brains. Overall, these data suggest that repeated HSV-1 reactivation into the brain may contribute to neurodegeneration also through oxidative damage.
RESUMO
An imbalance in GSH/GSSG ratio represents a triggering event in pro-inflammatory cytokine production and inflammatory response. However, the molecular mechanism(s) through which GSH regulates macrophage and cell autonomous inflammation remains not deeply understood. Here, we investigated the effects of a derivative of GSH, the N-butanoyl glutathione (GSH-C4), a cell permeable compound, on lipopolisaccharide (LPS)-stimulated murine RAW 264.7 macrophages, and human macrophages. LPS alone induces a significant production of pro-inflammatory cytokines, such as IL-1ß, IL-6, and TNF-α and a significant decrement of GSH content. Such events were significantly abrogated by treatment with GSH-C4. Moreover, GSH-C4 was highly efficient in buffering cell autonomous inflammatory status of aged C2C12 myotubes and 3T3-L1 adipocytes by suppressing the production of pro-inflammatory cytokines. We found that inflammation was paralleled by a strong induction of the phosphorylated form of NFκB, which translocates into the nucleus; a process that was also efficiently inhibited by the treatment with GSH-C4. Overall, the evidence suggests that GSH decrement is required for efficient activation of an inflammatory condition and, at the same time, GSH-C4 can be envisaged as a good candidate to abrogate such process, expanding the anti-inflammatory role of this molecule in chronic inflammatory states.