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1.
Neurochem Res ; 48(7): 2093-2103, 2023 Jul.
Article in English | MEDLINE | ID: mdl-36790580

ABSTRACT

Huntington's disease (HD) is a disease characterized by the progressive degeneration of nerve cells in the brain. DNA damage has been implicated in many neurological disorders; however, the association between this damage and the impaired signaling related to neurodegeneration is still unclear. The transcription factor c-AMP-responsive element binding protein (CREB) has a relevant role in the neuronal plasticity process regulating the expression of several genes, including brain-derived neurotrophic factor (BDNF). Here we analyzed the direct link between DNA damage and the expression of genes involved in neuronal plasticity. The study was performed in model cell lines STHdhQ7 (wild type) and STHdhQ111 (HD model). Treatment with Etoposide (Eto) was used to induce double-strand breaks (DSBs) to evaluate the DNA damage response (DDR) and the expression of synaptic plasticity genes. Eto treatment induced phosphorylation of ATM (p-ATM) and H2AX (γH2AX), markers of DDR, in both cell lines. Interestingly, upon DNA damage, STHdhQ7 cells showed increased expression of activity-regulated cytoskeleton associated protein (Arc) and BDNF when compared to the HD cell line model. Additionally, Eto induced CREB activation with a differential localization of its co-activators in the cell types analyzed. These results suggest that DSBs impact differentially the gene expression patterns of plasticity genes in the normal cell line versus the HD model. This effect is mediated by the impaired localization of CREB-binding protein (CBP) and histone acetylation in the HD model. Our results highlight the role of epigenetics and DNA repair on HD and therefore we suggest that future studies should explore in depth the epigenetic landscape on neuronal pathologies with the goal to further understand molecular mechanisms and pinpoint therapeutic targets.


Subject(s)
Huntington Disease , Humans , Huntington Disease/genetics , Huntington Disease/metabolism , Brain-Derived Neurotrophic Factor/genetics , DNA Damage , Signal Transduction , Neuronal Plasticity
2.
Rev Bras Parasitol Vet ; 30(4): e012721, 2021.
Article in English | MEDLINE | ID: mdl-34755807

ABSTRACT

This study aimed to investigate the genetic diversity of Hepatozoon spp. in rodents from Valdivia, Chile. A total of 74 rodents (synanthropic n=38; wild n=36) were trapped in Valdivia. We performed conventional PCR assays for Apicomplexa organisms targeting two overlapping 18S rDNA gene fragments (600 bp and 900 bp) followed by sequencing of selected amplicons. Hepatozoon spp. occurrence was 82.43% (61/74). Twelve sequences obtained from the 600 bp and ten from the 900 bp 18S rDNA fragments were identified as Hepatozoon sp. Six sequences obtained from 18S rDNA-based overlapping PCR protocols were used for concatenated (1,400 bp) phylogenetic, haplotype and distance analyses. Hepatozoon spp. 18S rDNA concatenated sequences from the present study were detected in Oligoryzomys longicaudatus, Rattus norvegicus, Mus musculus, and Abrothrix longipilis grouped with Hepatozoon species earlier described in rodents and reptiles from Chile and Brazil. Nucleotide polymorphism of the six 18S rDNA sequences (1,400 bp) from this study, and other Chilean sequences from rodents and rodent's ticks, showed high diversity with a total of nine Chilean haplotypes. Three haplotypes from Valdivia were identified for the first time in this study, suggesting the circulation of novel haplotypes in rodents from southern Chile.


Subject(s)
Eucoccidiida , Rodentia , Animals , Chile , Eucoccidiida/genetics , Genetic Variation , Mice , Phylogeny , RNA, Ribosomal, 18S/genetics , Rats
3.
Front Cell Neurosci ; 15: 580717, 2021.
Article in English | MEDLINE | ID: mdl-33708072

ABSTRACT

Herpes simplex virus type 1 (HSV-1) is a widespread neurotropic virus. Primary infection of HSV-1 in facial epithelium leads to retrograde axonal transport to the central nervous system (CNS) where it establishes latency. Under stressful conditions, the virus reactivates, and new progeny are transported anterogradely to the primary site of infection. During the late stages of neuronal infection, axonal damage can occur, however, the impact of HSV-1 infection on the morphology and functional integrity of neuronal dendrites during the early stages of infection is unknown. We previously demonstrated that acute HSV-1 infection in neuronal cell lines selectively enhances Arc protein expression - a major regulator of long-term synaptic plasticity and memory consolidation, known for being a protein-interaction hub in the postsynaptic dendritic compartment. Thus, HSV-1 induced Arc expression may alter the functionality of infected neurons and negatively impact dendritic spine dynamics. In this study we demonstrated that HSV-1 infection induces structural disassembly and functional deregulation in cultured cortical neurons, an altered glutamate response, Arc accumulation within the somata, and decreased expression of spine scaffolding-like proteins such as PSD-95, Drebrin and CaMKIIß. However, whether these alterations are specific to the HSV-1 infection mechanism or reflect a secondary neurodegenerative process remains to be determined.

4.
Rev. bras. parasitol. vet ; 30(4): e012721, 2021. graf
Article in English | LILACS, VETINDEX | ID: biblio-1347267

ABSTRACT

Abstract This study aimed to investigate the genetic diversity of Hepatozoon spp. in rodents from Valdivia, Chile. A total of 74 rodents (synanthropic n=38; wild n=36) were trapped in Valdivia. We performed conventional PCR assays for Apicomplexa organisms targeting two overlapping 18S rDNA gene fragments (600 bp and 900 bp) followed by sequencing of selected amplicons. Hepatozoon spp. occurrence was 82.43% (61/74). Twelve sequences obtained from the 600 bp and ten from the 900 bp 18S rDNA fragments were identified as Hepatozoon sp. Six sequences obtained from 18S rDNA-based overlapping PCR protocols were used for concatenated (1,400 bp) phylogenetic, haplotype and distance analyses. Hepatozoon spp. 18S rDNA concatenated sequences from the present study were detected in Oligoryzomys longicaudatus, Rattus norvegicus, Mus musculus, and Abrothrix longipilis grouped with Hepatozoon species earlier described in rodents and reptiles from Chile and Brazil. Nucleotide polymorphism of the six 18S rDNA sequences (1,400 bp) from this study, and other Chilean sequences from rodents and rodent's ticks, showed high diversity with a total of nine Chilean haplotypes. Three haplotypes from Valdivia were identified for the first time in this study, suggesting the circulation of novel haplotypes in rodents from southern Chile.


Resumo Este estudo teve como objetivo investigar a diversidade genética de Hepatozoon spp. em roedores de Valdivia, Chile. Um total de 74 roedores (sinantrópicos n=38; selvagens n=36) foram capturados. PCR convencional foi realizada para organismos Apicomplexa, visando dois fragmentos sobrepostos do gene 18S rDNA (600 bp e 900 bp), seguida pelo sequenciamento de amplicons selecionados. A ocorrência de Hepatozoon spp. foi de 82,43% (61/74). Doze sequências obtidas dos fragmentos de 18S rDNA de 600 pb e dez dos fragmentos de 18S rDNA de 900 pb foram identificadas como Hepatozoon sp. Seis sequências obtidas, a partir de protocolos de PCR sobrepostos, foram usadas para análises filogenéticas (1.400 bp), de haplótipos e de distância. Sequências concatenadas 18S rDNA do presente estudo foram detectadas em Oligoryzomys longicaudatus, Rattus norvegicus, Mus musculus e Abrothrix longipilis e agrupadas com Hepatozoon descrito em roedores e répteis do Chile e do Brasil. A análise de polimorfismos das seis sequências deste estudo, junto com outras sequências chilenas de roedores e carrapatos de roedores, mostrou alta diversidade com um total de nove haplótipos no Chile. Três haplótipos detectados em Valdivia foram identificados pela primeira vez neste estudo, sugerindo que novos haplótipos circulam em roedores do sul do Chile.


Subject(s)
Animals , Rabbits , Rats , Rodentia , Eucoccidiida/genetics , Phylogeny , Genetic Variation , RNA, Ribosomal, 18S/genetics , Chile
5.
Microorganisms ; 8(10)2020 Sep 29.
Article in English | MEDLINE | ID: mdl-33003287

ABSTRACT

Even though hemotrophic mycoplasma (hemoplasma) infections are well documented in a wide variety of hosts worldwide, there is a gap in the knowledge aobut hemoplasmas in rodents. This study aimed to molecularly survey and investigate the genetic diversity of hemoplasmas in rodents from Chile. Synanthropic and wild rodents (n = 74) were captured in the southern province of Valdivia (Corral, Valdivia, Riñihue, and Reumén localities). Spleen samples were submitted to a conventional PCR for hemotrophic Mycoplasma spp. targeting the 16S rRNA gene (800 bp), followed by sequencing, phylogenetic, and genetic diversity analyses. The overall occurrence of hemotrophic mycoplasmas in rodents from Valdivia was 24.5% (18/74) [95% CI (14.5; 34.1)]. Hemoplasmas were detected in Mus musculus (1/4), Rattus norvegicus (1/16), Abrothrix longipilis (7/13), A. olivaceo (6/8), and Oligoryzomys longicaudatus (3/10). The nucleotide polymorphism analysis of the targeted 16S rRNA region showed low diversity, with two genotypes and a high identity to the variants detected in wild rodents from Brazil. Hemoplasmas are described for the first time in rodents from Chile with a moderate occurrence and low 16S rDNA genetic diversity within the sampled rodent population. The detected hemoplasma genotypes were specific to rodents and were not shared with other mammals.

6.
Acta Trop ; 212: 105672, 2020 Dec.
Article in English | MEDLINE | ID: mdl-32835672

ABSTRACT

The aim of this study was to molecularly survey Bartonella spp. in rodents from the Valdivia Province, Southern Chile and from wild black rat-fleas in Guafo Island, Chilean Patagonia. Thrity-three spleens from synanthropic (Mus musculus, Rattus novergicus and Rattus rattus) and wild (Abrothrix longipilis, Oligoryzomys longicaudatus, Abrothrix sp.) rodents from Valdivia and 39 fleas/flea-pools (Plocopsylla sp. and Nosopsyllus sp.) from R. rattus in Guafo Island were obtained. All samples were screened by high-resolution melting (HRM) real-time PCR for Bartonella ITS locus (190 bp). ITS-Positive samples were further analyzed for two HRM real-time PCR assays targeting Bartonella rpoB (191 bp) and gltA (340 bp) gene fragments. All positive ITS, gltA and rpoB real-time PCR products were purified and sequenced. Bayesian inference trees were built for the gltA and rpoB gene fragments. Bartonella-ITS DNA was detected in 36.3% (12/33) [95% CI (22-53%)] of the tested rodents from Valdivia, being identified in all but O. longicaudatus rodent species captured in this study. ITS DNA was detected in 28% (11/39) [95% CI (16-43%)] of fleas/flea-pools from Guafo Island and identified in both Plocopsylla and Nosopsyllus genera. Sequencing and phylogenic analyses targeting three loci of Bartonella spp. allowed the identification of five genotypes in rodents from Southern Chile, potentially belonging to three different Bartonella spp. Those included Bartonella tribocorum identified from R. rattus, Bartonella rochalimae detected from Abrothix sp., and one novel genotype from uncharacterized Bartonella sp. identified in M. musculus, R. norvegicus, A. longipilis, and Abothrix sp., related to strains previously isolated in Phyllotis sp. from Peru. Additionally, two genotypes of B. tribocorum were identified in fleas from Guafo. In a nutshell, highly diverse and potentially zoonotic Bartonella spp. are described for the first time in wild and synanthropic rodents from Chile, and B. tribocorum was detected in wild back rat fleas from Guafo Island.


Subject(s)
Bartonella/isolation & purification , Rodentia/microbiology , Siphonaptera/microbiology , Animals , Bartonella/genetics , Chile , Female , Genotype , Male , Mice , Rats
7.
Front Cell Neurosci ; 14: 166, 2020.
Article in English | MEDLINE | ID: mdl-32655372

ABSTRACT

Kallikrein-related peptidases (KLKs) are a family of serine proteases that when dysregulated may contribute to neuroinflammation and neurodegeneration. In the present review article, we describe what is known about their physiological and pathological roles with an emphasis on KLK6 and KLK8, two KLKs that are highly expressed in the adult central nervous system (CNS). Altered expression and activity of KLK6 have been linked to brain physiology and the development of multiple sclerosis. On the other hand, altered levels of KLK6 in the brain and serum of people affected by Alzheimer's disease and Parkinson's disease have been documented, pointing out to its function in amyloid metabolism and development of synucleinopathies. People who have structural genetic variants of KLK8 can suffer mental illnesses such as intellectual and learning disabilities, seizures, and autism. Increased expression of KLK8 has also been implicated in schizophrenia, bipolar disorder, and depression. Also, we discuss the possible link that exists between KLKs activity and certain viral infections that can affect the nervous system. Although little is known about the exact mechanisms that mediate KLKs function and their participation in neuroinflammatory and neurodegenerative disorders will open a new field to develop novel therapies to modulate their levels and/or activity and their harmful effects on the CNS.

8.
J Virol ; 94(13)2020 06 16.
Article in English | MEDLINE | ID: mdl-32321811

ABSTRACT

The small messenger RNA (SmRNA) of the Andes orthohantavirus (ANDV), a rodent-borne member of the Hantaviridae family of viruses of the Bunyavirales order, encodes a multifunctional nucleocapsid (N) protein and for a nonstructural (NSs) protein of unknown function. We have previously shown the expression of the ANDV-NSs, but only in infected cell cultures. In this study, we extend our early findings by confirming the expression of the ANDV-NSs protein in the lungs of experimentally infected golden Syrian hamsters. Next, we show, using a virus-free system, that the ANDV-NSs protein antagonizes the type I interferon (IFN) induction pathway by suppressing signals downstream of the melanoma differentiation-associated protein 5 (MDA5) and the retinoic acid-inducible gene 1 (RIG-I) and upstream of TBK1. Consistent with this observation, the ANDV-NSs protein antagonized mitochondrial antiviral-signaling protein (MAVS)-induced IFN-ß, NF-κB, IFN-regulatory factor 3 (IRF3), and IFN-sensitive response element (ISRE) promoter activity. Results demonstrate that ANDV-NSs binds to MAVS in cells without disrupting the MAVS-TBK-1 interaction. However, in the presence of the ANDV-NSs ubiquitination of MAVS is reduced. In summary, this study provides evidence showing that the ANDV-NSs protein acts as an antagonist of the cellular innate immune system by suppressing MAVS downstream signaling by a yet not fully understand mechanism. Our findings reveal new insights into the molecular regulation of the hosts' innate immune response by the Andes orthohantavirus.IMPORTANCEAndes orthohantavirus (ANDV) is endemic in Argentina and Chile and is the primary etiological agent of hantavirus cardiopulmonary syndrome (HCPS) in South America. ANDV is distinguished from other hantaviruses by its unique ability to spread from person to person. In a previous report, we identified a novel ANDV protein, ANDV-NSs. Until now, ANDV-NSs had no known function. In this new study, we established that ANDV-NSs acts as an antagonist of cellular innate immunity, the first line of defense against invading pathogens, hindering the cellular antiviral response during infection. This study provides novel insights into the mechanisms used by ANDV to establish its infection.


Subject(s)
Adaptor Proteins, Signal Transducing/metabolism , Orthohantavirus/genetics , Viral Nonstructural Proteins/genetics , Animals , Cell Line , Chlorocebus aethiops , HEK293 Cells , Hantavirus Infections/genetics , Host-Pathogen Interactions/immunology , Humans , Immunity, Innate/immunology , Interferon Regulatory Factor-3/metabolism , Interferon Type I/metabolism , Interferon-beta/genetics , NF-kappa B/metabolism , Protein Serine-Threonine Kinases/metabolism , Signal Transduction/immunology , Vero Cells , Viral Nonstructural Proteins/metabolism
9.
Arch Microbiol ; 201(8): 1075-1083, 2019 Oct.
Article in English | MEDLINE | ID: mdl-31123791

ABSTRACT

Arcobacter butzleri is an emerging foodborne zoonotic pathogen that has been isolated from environmental water sources. This pathogen establishes in vitro endosymbiotic relationships with Acanthamoeba castellanii, a free-living amoeba found in environmental matrices such as soil and water. The principal aim of this study was to analyse the transcriptional pattern of flagellar (flaA-flaB-flgH-motA) and other putative virulence genes (ciaB-cadF-mviN-pldA) of A. butzleri during its interaction with A. castellanii by quantitative real-time PCR. The transcriptional analysis showed up-regulation of all genes analysed before A. butzleri became established as an endocytobiont of A. castellanii. In contrast, while A. butzleri remains an endocytobiont, a significant and sustained decrease in the transcription of all analysed genes was observed. Our findings suggest that A. butzleri requires a biphasic transcriptional pattern of flagellar and other putative virulence genes to establish an endosymbiotic relationship with A. castellanii.


Subject(s)
Acanthamoeba castellanii/microbiology , Arcobacter/genetics , Arcobacter/pathogenicity , Flagella/genetics , Symbiosis/genetics , Animals , Arcobacter/isolation & purification , Bacterial Outer Membrane Proteins/genetics , Bacterial Proteins/genetics , Flagellin/genetics , Virulence/genetics , Virulence Factors/genetics
10.
Front Microbiol ; 10: 2992, 2019.
Article in English | MEDLINE | ID: mdl-31998273

ABSTRACT

In South America Andes hantavirus (ANDV) is hosted by the rodent Oligoryzomys longicaudatus (also known as pygmy rice rat). In humans, ANDV causes Hantavirus Pulmonary Syndrome (HPS), with a fatality rate of about 40%. Epidemiologic and molecular evidence has shown that ANDV can be transmitted from person to person. Sin Nombre hantavirus, occurring in North America, and ANDV are genetically related, and both cause HPS with similar clinical evolution and mortality rate. However, only ANDV is transmitted from person to person. A recent hantavirus outbreak in a small village in Southern Argentine, with 29 HPS cases and 11 deaths has brought to mind that person-to-person transmission continues to be a public health emergency. The present investigation was aimed to understand how does ANDV actually spread between persons. Tissue samples of lung and salivary glands from infected Oligoryzomys longicaudatus and lethal cases of human HPS were investigated by bright field immunocytochemistry, multichannel immunofluorescence, and transmission electron microscopy. The findings are consistent with ANDV infection and replication in the lung alveolar epithelium and macrophages, and in the secretory cells of the submandibular salivary glands. In the lung of infected Oligoryzomys longicaudatus and human cases HPS, the bulk of immunoreactive hantavirus antigens was localized in epithelial cells of the alveolar walls and macrophages. The ultrastructural study supports that in the lung of HPS patients the virus replicates in the alveolar epithelial cells with virus particles being discharged into the alveolar lumen. Virus-like particles were seen within vacuoles of the lung macrophages. Considering that these macrophages can reach the conductive segments of the airways, their expectoration becomes a deadly bullet for ANDV transmission. In the submandibular glands of infected rodents and HPS cases, ANDV antigens were in capillary endothelium, the secretory cells and filling the lumen of the excretory pathway. It is proposed that in patients with HPS caused by ANDV the alveolar epithelium and macrophages would be the gate for the airway spreading of the virus, while the salivary glands are a target for virus replication and an exit pathway through saliva.

11.
Front Cell Neurosci ; 12: 126, 2018.
Article in English | MEDLINE | ID: mdl-29867359

ABSTRACT

Alzheimer's disease (AD) is the most common cause of age-related dementia leading to severe irreversible cognitive decline and massive neurodegeneration. While therapeutic approaches for managing symptoms are available, AD currently has no cure. AD associates with a progressive decline of the two major catabolic pathways of eukaryotic cells-the autophagy-lysosomal pathway (ALP) and the ubiquitin-proteasome system (UPS)-that contributes to the accumulation of harmful molecules implicated in synaptic plasticity and long-term memory impairment. One protein recently highlighted as the earliest initiator of these disturbances is the amyloid precursor protein (APP) intracellular C-terminal membrane fragment ß (CTFß), a key toxic agent with deleterious effects on neuronal function that has become an important pathogenic factor for AD and a potential biomarker for AD patients. This review focuses on the involvement of regulatory molecules and specific post-translational modifications (PTMs) that operate in the UPS and ALP to control a single proteostasis network to achieve protein balance. We discuss how these aspects can contribute to the development of novel strategies to strengthen the balance of key pathogenic proteins associated with AD.

12.
Front Cell Neurosci ; 12: 505, 2018.
Article in English | MEDLINE | ID: mdl-30692913

ABSTRACT

Herpes simplex virus type 1 (HSV-1) is a neurotropic virus able to reach the central nervous system (CNS) after primary infection in oronasal mucosa. HSV-1 establishes latency inside neurons due the repression of its gene expression process, which is related to periodic reactivations in response to cellular stress conditions, constituting a risk factor for neurodegenerative diseases such as Alzheimer's disease (AD). The immediate-early gene Arc plays an essential role in neuronal morphology, synaptic plasticity and memory formation. Arc acts as a hub protein, interacting with components of the endocytic machinery required for AMPA receptor (AMPAR) recycling as well as with proteins of the post-synaptic density and actin cytoskeleton. However, to date, no studies have evaluated whether persistent neurotropic HSV-1 infection modulates the expression or function of Arc protein in brain tissue. Here, we report that neuronal in vivo and in vitro infection of HSV-1 significantly increases Arc protein levels, showing a robust perinuclear distribution in neuronal cell lines, a process that is dependent on an active HSV-1 replication cycle. Finally, we found that silencing Arc protein caused a decrease in HSV-1 proteins and viral progeny, suggesting that Arc is involved in the lifecycle of HSV-1. Our studies strongly suggest that pathogenicity of HSV-1 neuronal reactivations in humans could be mediated in part by Arc neuronal upregulation and its potential role in endocytic trafficking and AMPA-neuronal function impairment. Further studies are necessary to define whether this phenomenon could have repercussions in cognition and learning processes in infected individuals.

13.
Molecules ; 23(1)2017 Dec 21.
Article in English | MEDLINE | ID: mdl-29267250

ABSTRACT

Resveratrol is a polyphenolic natural compound produced by a variety of crops. Currently, resveratrol is considered a multi-target anti-cancer agent with pleiotropic activity, including the ability to prevent the proliferation of malignant cells by inhibiting angiogenesis and curtailing invasive and metastatic factors in many cancer models. However, the molecular mechanisms mediating resveratrol-specific effects on lymphoma cells remain unknown. To begin tackling this question, we treated the Burkitt's lymphoma cell line Ramos with resveratrol and assessed cell survival and gene expression. Our results suggest that resveratrol shows a significant anti-proliferative and pro-apoptotic activity on Ramos cells, inducing the DNA damage response, DNA repairing, and modulating the expression of several genes that regulate the apoptotic process and their proliferative activity.


Subject(s)
Antineoplastic Agents/chemistry , Resveratrol/chemistry , Antineoplastic Agents/pharmacology , Apoptosis/drug effects , Burkitt Lymphoma , Cell Line, Tumor , Cell Proliferation/drug effects , Cell Survival/drug effects , DNA Damage/drug effects , Humans , Resveratrol/pharmacology
14.
Mol Immunol ; 92: 169-179, 2017 12.
Article in English | MEDLINE | ID: mdl-29101849

ABSTRACT

The immediate early response 3 (IER3) is a key regulatory factor in the immune response, particularly as related to homeostasis immunomodulation via the nuclear factor kappa B (NF-κB) signaling pathway. The IER3 gene has been identified in mammals and, more recently, in other higher vertebrates. Nevertheless, relatively little is known about this regulator in bovines. Therefore, this study explored, characterized, and compared the genetic context of bovine IER3 to homologous genes in the human, mouse, and canine chromosomes. In silico analysis identified several regions of interest preserved in phylogenetically distant species. Similar analyses were also conducted for interleukin-8, a cytokine in which several putative cis elements were identified for the inducible transcription factor NF-κB. Subsequent challenge assays against the bovine viral diarrhea virus-1 revealed NF-κB signaling pathway activation just 15min post-infection, a process blocked by the BAY-117085 inhibitor. Similarly, infection strongly increased IER3 expression. Interestingly, IER3 down-regulated interleukin-8 expression, as confirmed by IER3 gene inhibition using small interfering RNA, RT-qPCR, and luciferase assays. In conclusion, this is the first report to present data indicating that bovine IER3 is a strong regulator of immune-marker expression, specifically modulating bovine interleukin-8 activation through the NF-κB/IER3 pathway in response to the bovine viral diarrhea virus.


Subject(s)
Apoptosis Regulatory Proteins/immunology , Bovine Virus Diarrhea-Mucosal Disease/immunology , Diarrhea Virus 1, Bovine Viral/immunology , Interleukin-8/immunology , NF-kappa B/immunology , Signal Transduction/immunology , Animals , Cattle , Dogs , Madin Darby Canine Kidney Cells
15.
Article in English | MEDLINE | ID: mdl-28879169

ABSTRACT

Herpes simplex virus type 1 (HSV-1) is a ubiquitous pathogen that establishes a latent persistent neuronal infection in humans. The pathogenic effects of repeated viral reactivation in infected neurons are still unknown. Several studies have reported that during HSV-1 epithelial infection, the virus could modulate diverse cell signaling pathways remodeling the Golgi apparatus (GA) membranes, but the molecular mechanisms implicated, and the functional consequences to neurons is currently unknown. Here we report that infection of primary neuronal cultures with HSV-1 triggers Src tyrosine kinase activation and subsequent phosphorylation of Dynamin 2 GTPase, two players with a role in GA integrity maintenance. Immunofluorescence analyses showed that HSV-1 productive neuronal infection caused a scattered and fragmented distribution of the GA through the cytoplasm, contrasting with the uniform perinuclear distribution pattern observed in control cells. In addition, transmission electron microscopy revealed swollen cisternae and disorganized stacks in HSV-1 infected neurons compared to control cells. Interestingly, PP2, a selective inhibitor for Src-family kinases markedly reduced these morphological alterations of the GA induced by HSV-1 infection strongly supporting the possible involvement of Src tyrosine kinase. Finally, we showed that HSV-1 tegument protein VP11/12 is necessary but not sufficient to induce Dyn2 phosphorylation. Altogether, these results show that HSV-1 neuronal infection triggers activation of Src tyrosine kinase, phosphorylation of Dynamin 2 GTPase, and perturbation of GA integrity. These findings suggest a possible neuropathogenic mechanism triggered by HSV-1 infection, which could involve dysfunction of the secretory system in neurons and central nervous system.


Subject(s)
GTP Phosphohydrolases/metabolism , Golgi Apparatus/metabolism , Golgi Apparatus/virology , Herpesvirus 1, Human/pathogenicity , src-Family Kinases/metabolism , Animals , Antigens, Viral/metabolism , Cell Line , Cell Membrane/metabolism , Cell Survival , Central Nervous System/metabolism , Central Nervous System/virology , Chlorocebus aethiops , Cytoplasm/metabolism , Cytoplasm/virology , Dynamin II , Dynamins/metabolism , Gene Expression Regulation, Viral , Genes, Viral/genetics , Golgi Apparatus/ultrastructure , Herpesvirus 1, Human/genetics , Humans , Mice , Microscopy, Electron, Transmission , Neurons/metabolism , Neurons/virology , Phosphorylation , Pyrimidines/pharmacology , Signal Transduction , Vero Cells , Viral Proteins/metabolism , src-Family Kinases/drug effects
16.
Dev Comp Immunol ; 77: 23-29, 2017 12.
Article in English | MEDLINE | ID: mdl-28735964

ABSTRACT

Viruses have developed cellular strategies to ensure progeny survival. One of the most interesting is immune camouflage, where the virus triggers a controlled-intensity immune response that prevents total destruction of the infected cell, thus "winning time" for the virus. This study explored the regulatory contexts of the bovine A20 gene during bovine viral diarrhea virus (BVDV)-1 infection, using IL-8 as an immune-response sentinel molecule. Assessments were conducted through RT-qPCR, Western blotting, gene silencing/overexpression, luciferase assays, and the use of pharmacological inhibitors, among other approaches. The results demonstrated that a) BVDV-1 increased A20 levels in Madin-Darby bovine kidney cells, b) increased A20 led to decreased IL-8 expression, and c) the virus affected the NF-κB signaling pathway. Collectively, these data identify bovine A20 as a strong regulator of immune marker expression. In conclusion, this is the first report on BVDV-1 modulating bovine IL-8 activation through the NF-κB/A20 pathway.


Subject(s)
Bovine Virus Diarrhea-Mucosal Disease/immunology , Diarrhea Virus 1, Bovine Viral/immunology , Epithelial Cells/metabolism , Interleukin-8/metabolism , NF-kappa B/metabolism , Tumor Necrosis Factor alpha-Induced Protein 3/metabolism , Animals , Cattle , Cell Line , Epithelial Cells/pathology , Epithelial Cells/virology , Gene Expression Regulation , Immunity/genetics , Immunomodulation , Kidney/pathology , RNA, Small Interfering/genetics , Signal Transduction , Tumor Necrosis Factor alpha-Induced Protein 3/genetics
17.
J Cell Biochem ; 118(6): 1330-1340, 2017 06.
Article in English | MEDLINE | ID: mdl-27862234

ABSTRACT

Interleukin-3 (IL-3) is a well-characterized growth factor in hematopoietic cells, but it is also expressed in other cell types with poorly described functions. Many studies have provided evidence that IL-3 plays an important role in cell survival. We have previously shown that IL-3 is able to increase glucose uptake in HEK293 cells, suggesting that this factor requires sustained glucose metabolism to promote cell survival. In this study, we demonstrate that IL-3 contributes to cell survival under oxidative stress, a prominent feature in the pathophysiology of cancer, diabetes, and neurodegenerative diseases, as well as in the aging process. Our results suggest a molecular mechanism that involves signaling pathways mediated by PI-3k/Akt and Erk. Altogether, these findings show an important role for IL-3 in supporting the viability of non-hematopoietic systems. J. Cell. Biochem. 118: 1330-1340, 2017. © 2016 Wiley Periodicals, Inc.


Subject(s)
Glucose/metabolism , Hydrogen Peroxide/adverse effects , Interleukin-3/metabolism , Cell Death , Cell Survival/drug effects , Extracellular Signal-Regulated MAP Kinases/metabolism , HEK293 Cells , Humans , Oxidative Stress , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Signal Transduction/drug effects
18.
Rev Chilena Infectol ; 33(3): 275-81, 2016 Jun.
Article in Spanish | MEDLINE | ID: mdl-27598275

ABSTRACT

BACKGROUND: Currently in Chile, due to the frequent clinical suspicion of Hantavirus disease and the high public health impact that this causes, it is necessary to strengthen the criteria for clinical and epidemiological suspicion in the health team. OBJECTIVE: To analyze the information contained in the reports of suspected Hantavirus infection versus the confirmatory diagnosis with the reference technique, IgM capture ELISA anti-hantavirus. Material andMethods: Correlation between the information provided in notifications versus the result of confirmation was analyzed by calculating diagnostic accuracy. RESULTS: 3.4% of 1,566 patients studied (53 cases) was confirmed as SCPH. 58.6% of the analyzed notifications was incomplete. The percentage of positivity of the reference technique associated with fever, myalgia and headache was 80-85%. The presence of immunoblasts (> 10%) showed 25% sensitivity, 98% specificity, 37% PPV, 97% NPV. Thrombocytopenia exhibited 98% sensitivity, 74% specificity, 16% PPV, 100% NPV. CONCLUSION: It is necessary to reinforce the importance of comprehensive data reporting at the health system level. The presence of thrombocytopenia and immunoblasts (> 10%) is highly sensitive and specific, respectively, for detecting patients with SCPH. There is a need to develop training programs in order to optimize the suspicion of Hantavirus infection and appropriate use of health resources.


Subject(s)
Disease Notification/standards , Hantaan virus/isolation & purification , Hantavirus Pulmonary Syndrome/diagnosis , Hemorrhagic Fever with Renal Syndrome/diagnosis , Adolescent , Adult , Aged , Aged, 80 and over , Antibodies, Viral/blood , Child , Child, Preschool , Chile , Enzyme-Linked Immunosorbent Assay , Female , Hantavirus Pulmonary Syndrome/blood , Hemorrhagic Fever with Renal Syndrome/blood , Humans , Immunoglobulin M/blood , Infant , Male , Middle Aged , Reference Standards , Reference Values , Sensitivity and Specificity , Seroepidemiologic Studies , Serologic Tests/methods , Thrombocytopenia/blood , Thrombocytopenia/diagnosis , Young Adult
19.
Rev. chil. infectol ; 33(3): 275-281, jun. 2016. ilus, tab
Article in Spanish | LILACS | ID: lil-791019

ABSTRACT

Antecedentes: Actualmente en Chile, debido a la elevada sospecha clínica de enfermedad por hantavirus y el alto impacto en salud pública que esto provoca, se hace necesario reforzar al equipo de salud, los criterios de sospecha clínica y epidemiológica de hantavirosis. Objetivo: Analizar la información contenida en las notificaciones de sospecha de infección por hantavirus versus la técnica de referencia para el diagnóstico confirmatorio de casos sospechosos, ELISA IgM de captura anti-hantavirus. Material y Método: Mediante cálculo de precisión diagnóstica se analizó la correlación que existe entre la información entregada en las notificaciones versus el resultado de la confirmación mediante la técnica de referencia. Resultados: De 1.566 pacientes estudiados 3,4% (53 casos) fue confirmado para SCPH. De las notificaciones analizadas 58,6% estaban con datos incompletos. Los porcentajes de positividad de la técnica de referencia asociada a fiebre, mialgia y cefalea, fueron de 80-85%. Destaca que la presencia de inmunoblastos (> 10%), presenta: S: 25%, E: 98%, VPP: 37%, VPN: 97%. Paratrombocitopenia se obtuvo: S: 98%, E: 74%, VPP: 16%, VPN: 100%. Conclusión: Se hace necesario reiterar a nivel del sistema sanitario chileno la importancia de contar con datos completos en los formularios de notificación. La presencia de trombocitopenia e inmunoblastos (> 10%) fue altamente sensible y especifica, respectivamente, en la detección de pacientes con SCPH. Con el fin de optimizar la sospecha de infección por hantavirus, según la definición de caso sospechoso, se plantea la necesidad de desarrollar programas de capacitación para la sospecha clínica y lectura de parámetros de laboratorio, tales como presencia de inmunoblastos en el hemograma, así como incluir un algoritmo con el fin de optimizar la sospecha y el uso adecuado de los recursos sanitarios.


Background: Currently in Chile, due to the frequent clinical suspicion of Hantavirus disease and the high public health impact that this causes, it is necessary to strengthen the criteria for clinical and epidemiological suspicion in the health team. Objective: To analyze the information contained in the reports of suspected Hantavirus infection versus the confirmatory diagnosis with the reference technique, IgM capture ELISA anti-hantavirus. Material andMethods: Correlation between the information provided in notifications versus the result of confirmation was analyzed by calculating diagnostic accuracy. Results: 3.4% of 1,566 patients studied (53 cases) was confirmed as SCPH. 58.6% of the analyzed notifications was incomplete. The percentage of positivity of the reference technique associated with fever, myalgia and headache was 80-85%. The presence of immunoblasts (> 10%) showed 25% sensitivity, 98% specificity, 37% PPV, 97% NPV. Thrombocytopenia exhibited 98% sensitivity, 74% specificity, 16% PPV, 100% NPV. Conclusion: It is necessary to reinforce the importance of comprehensive data reporting at the health system level. The presence of thrombocytopenia and immunoblasts (> 10%) is highly sensitive and specific, respectively, for detecting patients with SCPH. There is a need to develop training programs in order to optimize the suspicion of Hantavirus infection and appropriate use of health resources.


Subject(s)
Humans , Male , Female , Infant , Child, Preschool , Child , Adolescent , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Hantaan virus/isolation & purification , Hantavirus Pulmonary Syndrome/diagnosis , Disease Notification/standards , Hemorrhagic Fever with Renal Syndrome/diagnosis , Reference Standards , Reference Values , Thrombocytopenia/diagnosis , Thrombocytopenia/blood , Immunoglobulin M/blood , Enzyme-Linked Immunosorbent Assay , Serologic Tests/methods , Seroepidemiologic Studies , Chile , Sensitivity and Specificity , Hantavirus Pulmonary Syndrome/blood , Hemorrhagic Fever with Renal Syndrome/blood , Antibodies, Viral/blood
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