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1.
Oncogene ; 43(11): 804-820, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38279062

RESUMO

HJURP is overexpressed in several cancer types and strongly correlates with patient survival. However, the mechanistic basis underlying the association of HJURP with cancer aggressiveness is not well understood. HJURP promotes the loading of the histone H3 variant, CENP-A, at the centromeric chromatin, epigenetically defining the centromeres and supporting proper chromosome segregation. In addition, HJURP is associated with DNA repair but its function in this process is still scarcely explored. Here, we demonstrate that HJURP is recruited to DSBs through a mechanism requiring chromatin PARylation and promotes epigenetic alterations that favor the execution of DNA repair. Incorporation of HJURP at DSBs promotes turnover of H3K9me3 and HP1, facilitating DNA damage signaling and DSB repair. Moreover, HJURP overexpression in glioma cell lines also affected global structure of heterochromatin independently of DNA damage induction, promoting genome-wide reorganization and assisting DNA damage response. HJURP overexpression therefore extensively alters DNA damage signaling and DSB repair, and also increases radioresistance of glioma cells. Importantly, HJURP expression levels in tumors are also associated with poor response of patients to radiation. Thus, our results enlarge the understanding of HJURP involvement in DNA repair and highlight it as a promising target for the development of adjuvant therapies that sensitize tumor cells to irradiation.


Assuntos
Cromatina , Glioma , Humanos , Centrômero/metabolismo , Proteína Centromérica A/genética , Proteína Centromérica A/metabolismo , Cromatina/genética , Proteínas Cromossômicas não Histona/genética , Proteínas Cromossômicas não Histona/metabolismo , Reparo do DNA/genética , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Glioma/genética
2.
iScience ; 26(10): 107947, 2023 Oct 20.
Artigo em Inglês | MEDLINE | ID: mdl-37841583

RESUMO

Invariant Natural Killer T (iNKT) cell activation by α-galactosylceramide (αGC) potentiates cytotoxic immune responses against tumors. However, αGC-induced liver injury is a limiting factor for iNKT-based immunotherapy. Although adrenergic receptor stimulation is an important immunosuppressive signal that curbs tissue damage induced by inflammation, its effect on the antitumor activity of invariant Natural Killer T (iNKT) cells remains unclear. We use mouse models and pharmacological tools to show that the stimulation of the sympathetic nervous system (SNS) inhibits αGC-induced liver injury without impairing iNKT cells' antitumoral functions. Mechanistically, SNS stimulation prevents the collateral effect of TNF-α production by iNKT cells and neutrophil accumulation in hepatic parenchyma. Our results suggest that the modulation of the adrenergic signaling can be a complementary approach to αGC-based immunotherapy to mitigate iNKT-induced liver injury without compromising its antitumoral activity.

3.
PLoS One ; 18(3): e0283696, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37000792

RESUMO

Leishmania is a protozoan that causes leishmaniasis, a neglected tropical disease with clinical manifestations classified as cutaneous, mucocutaneous, and visceral leishmaniasis. In the infection context, the parasite can modulate macrophage gene expression affecting the microbicidal activity and immune response. The metabolism of L-arginine into polyamines putrescine, spermidine, and spermine reduces nitric oxide (NO) production, favoring Leishmania survival. Here, we investigate the effect of supplementation with L-arginine and polyamines in infection of murine BALB/c macrophages by L. amazonensis and in the transcriptional regulation of genes involved in arginine metabolism and proinflammatory response. We showed a reduction in the percentage of infected macrophages upon putrescine supplementation compared to L-arginine, spermidine, and spermine supplementation. Unexpectedly, deprivation of L-arginine increased nitric oxide synthase (Nos2) gene expression without changes in NO production. Putrescine supplementation increased transcript levels of polyamine metabolism-related genes Arg2, ornithine decarboxylase (Odc1), Spermidine synthase (SpdS), and Spermine synthase (SpmS), but reduced Arg1 in L. amazonensis infected macrophages, while spermidine and spermine promoted opposite effects. Putrescine increased Nos2 expression without leading to NO production, while L-arginine plus spermine led to NO production in uninfected macrophages, suggesting that polyamines can induce NO production. Besides, L-arginine supplementation reduced Il-1b during infection, and L-arginine or L-arginine plus putrescine increased Mcp1 at 24h of infection, suggesting that polyamines availability can interfere with cytokine/chemokine production. Our data showed that putrescine shifts L-arginine-metabolism related-genes on BALB/c macrophages and affects infection by L. amazonensis.


Assuntos
Leishmania , Leishmaniose , Animais , Camundongos , Putrescina/farmacologia , Putrescina/metabolismo , Espermidina/farmacologia , Espermidina/metabolismo , Espermina/metabolismo , Poliaminas/metabolismo , Leishmaniose/tratamento farmacológico , Ornitina Descarboxilase/genética , Ornitina Descarboxilase/metabolismo , Óxido Nítrico Sintase/metabolismo , Macrófagos/metabolismo , Arginina/farmacologia , Arginina/metabolismo , Suplementos Nutricionais
4.
Int J Mol Sci ; 23(18)2022 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-36142200

RESUMO

Viral infections have always been a serious burden to public health, increasing morbidity and mortality rates worldwide. Zika virus (ZIKV) is a flavivirus transmitted by the Aedes aegypti vector and the causative agent of severe fetal neuropathogenesis and microcephaly. The virus crosses the placenta and reaches the fetal brain, mainly causing the death of neuronal precursor cells (NPCs), glial inflammation, and subsequent tissue damage. Genetic differences, mainly related to the antiviral immune response and cell death pathways greatly influence the susceptibility to infection. These components are modulated by many factors, including microRNAs (miRNAs). MiRNAs are small noncoding RNAs that regulate post-transcriptionally the overall gene expression, including genes for the neurodevelopment and the formation of neural circuits. In this context, we investigated the pathways and target genes of miRNAs modulated in NPCs infected with ZIKV. We observed downregulation of miR-302b, miR-302c and miR-194, whereas miR-30c was upregulated in ZIKV infected human NPCs in vitro. The analysis of a public dataset of ZIKV-infected human NPCs evidenced 262 upregulated and 3 downregulated genes, of which 142 were the target of the aforementioned miRNAs. Further, we confirmed a correlation between miRNA and target genes affecting pathways related to antiviral immune response, cell death and immune cells chemotaxis, all of which could contribute to the establishment of microcephaly and brain lesions. Here, we suggest that miRNAs target gene expression in infected NPCs, directly contributing to the pathogenesis of fetal microcephaly.


Assuntos
MicroRNAs , Microcefalia , Malformações do Sistema Nervoso , Infecção por Zika virus , Zika virus , Animais , Antivirais , Morte Celular/genética , Quimiotaxia , Feminino , Humanos , Imunidade , MicroRNAs/genética , Microcefalia/genética , Mosquitos Vetores , Gravidez , Zika virus/fisiologia
5.
J Neurochem ; 163(2): 113-132, 2022 10.
Artigo em Inglês | MEDLINE | ID: mdl-35880385

RESUMO

COVID-19 causes more than million deaths worldwide. Although much is understood about the immunopathogenesis of the lung disease, a lot remains to be known on the neurological impact of COVID-19. Here, we evaluated immunometabolic changes using astrocytes in vitro and dissected brain areas of SARS-CoV-2 infected Syrian hamsters. We show that SARS-CoV-2 alters proteins of carbon metabolism, glycolysis, and synaptic transmission, many of which are altered in neurological diseases. Real-time respirometry evidenced hyperactivation of glycolysis, further confirmed by metabolomics, with intense consumption of glucose, pyruvate, glutamine, and alpha ketoglutarate. Consistent with glutamine reduction, the blockade of glutaminolysis impaired viral replication and inflammatory response in vitro. SARS-CoV-2 was detected in vivo in hippocampus, cortex, and olfactory bulb of intranasally infected animals. Our data evidence an imbalance in important metabolic molecules and neurotransmitters in infected astrocytes. We suggest this may correlate with the neurological impairment observed during COVID-19, as memory loss, confusion, and cognitive impairment.


Assuntos
COVID-19 , Animais , Astrócitos , Carbono , Cricetinae , Modelos Animais de Doenças , Glucose , Glutamina , Ácidos Cetoglutáricos , Mesocricetus , Piruvatos , SARS-CoV-2
6.
Neurol Sci ; 43(11): 6271-6278, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-35849199

RESUMO

Multiple sclerosis (MS) is a chronic demyelinating autoimmune disease that affects the central nervous system (CNS), varying from relatively benign to severely disabling. Although the roles of several cytokines and chemokines in MS are well established, their roles in MS lesions and evolution remain a matter of debate. Soluble CD40L (sCD40L) is a ligand that induces lymphocyte proinflammatory activity by stimulating the activation and maturation of B cells, promoting isotype switching and affinity hypermutation. Circulating sCD40L levels reflect activation of the CD40-CD40L complex. The interaction between CD40 and CD40L is of fundamental importance, suggesting their role in MS pathogenesis. Interleukin-31 (IL-31) is a proinflammatory cytokine that plays a role in allergies, autoimmune diseases, and is a major factor in several chronic inflammatory diseases. IL-31 triggers the JAK-STAT pathway in several different cell types, to induce proliferation and tissue remodeling in fibroblasts, epithelial cells, and endothelial cells. Some studies have described a correlation between these two cytokines and decreased serum levels of sCD40L and IL-31 after MS treatment, accompanied by a lower inflammatory response. In this review, we emphasize the possible correlation and positive feedback between IL31 and sCD40L in the MS proinflammatory response. We also describe the justification for this hypothesis and whether it is possible to investigate these cytokines as biomarkers of MS.


Assuntos
Ligante de CD40 , Esclerose Múltipla , Humanos , Ligante de CD40/metabolismo , Células Endoteliais/metabolismo , Janus Quinases/metabolismo , Fatores de Transcrição STAT/metabolismo , Transdução de Sinais , Biomarcadores , Interleucinas , Citocinas
7.
J Interferon Cytokine Res ; 42(4): 153-160, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35384725

RESUMO

Rapamycin is an immunomodulatory drug that has been evaluated in preclinical and clinical trials as a disease-modifying therapy for multiple sclerosis (MS). In this study, we evaluated the in vitro effect of rapamycin on immune cells pivotally involved in the pathogenesis of experimental autoimmune encephalomyelitis (EAE), which is an animal model to study MS. Splenocytes and central nervous system (CNS)-mononuclear cells obtained from EAE mice were stimulated with a myelin oligodendrocyte glycoprotein peptide, whereas the microglial BV-2 cell line was activated with LPS. The 3 immune cell types were simultaneously treated with rapamycin, incubated, and then used to analyze cytokines, transcription factors, and activation markers. Rapamycin reduced IL-17 production, TBX21, and RORc expression by splenic and CNS cell cultures. IFN-γ and TNF-α production were also decreased in CNS cultures. This treatment also decreased TNF-α, IL-6, MHC II, CD40, and CD86 expression by BV-2 cells. These results indicated that in vivo immunomodulatory activity of rapamycin in MS and EAE was, in many aspects, reproduced by in vitro assays done with cells derived from the spleen and the CNS of EAE mice. This procedure could constitute a screening strategy for choosing drugs with therapeutic potential for MS.


Assuntos
Encefalomielite Autoimune Experimental , Esclerose Múltipla , Animais , Citocinas/metabolismo , Encefalomielite Autoimune Experimental/tratamento farmacológico , Encefalomielite Autoimune Experimental/metabolismo , Lipopolissacarídeos/farmacologia , Camundongos , Camundongos Endogâmicos C57BL , Microglia/metabolismo , Microglia/patologia , Fragmentos de Peptídeos/metabolismo , Fragmentos de Peptídeos/farmacologia , Sirolimo/metabolismo , Sirolimo/farmacologia , Sirolimo/uso terapêutico , Fator de Necrose Tumoral alfa/metabolismo
8.
Cells ; 11(5)2022 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-35269470

RESUMO

Severe COVID-19 patients present a clinical and laboratory overlap with other hyperinflammatory conditions such as hemophagocytic lymphohistiocytosis (HLH). However, the underlying mechanisms of these conditions remain to be explored. Here, we investigated the transcriptome of 1596 individuals, including patients with COVID-19 in comparison to healthy controls, other acute inflammatory states (HLH, multisystem inflammatory syndrome in children [MIS-C], Kawasaki disease [KD]), and different respiratory infections (seasonal coronavirus, influenza, bacterial pneumonia). We observed that COVID-19 and HLH share immunological pathways (cytokine/chemokine signaling and neutrophil-mediated immune responses), including gene signatures that stratify COVID-19 patients admitted to the intensive care unit (ICU) and COVID-19_nonICU patients. Of note, among the common differentially expressed genes (DEG), there is a cluster of neutrophil-associated genes that reflects a generalized hyperinflammatory state since it is also dysregulated in patients with KD and bacterial pneumonia. These genes are dysregulated at the protein level across several COVID-19 studies and form an interconnected network with differentially expressed plasma proteins that point to neutrophil hyperactivation in COVID-19 patients admitted to the intensive care unit. scRNAseq analysis indicated that these genes are specifically upregulated across different leukocyte populations, including lymphocyte subsets and immature neutrophils. Artificial intelligence modeling confirmed the strong association of these genes with COVID-19 severity. Thus, our work indicates putative therapeutic pathways for intervention.


Assuntos
COVID-19 , Linfo-Histiocitose Hemofagocítica , Inteligência Artificial , COVID-19/complicações , COVID-19/genética , Criança , Humanos , Linfo-Histiocitose Hemofagocítica/complicações , Ativação de Neutrófilo , SARS-CoV-2 , Síndrome de Resposta Inflamatória Sistêmica
9.
Mult Scler Relat Disord ; 57: 103321, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35158439

RESUMO

We report on nine patients (eight cases of MS and one case of NMOSD) who presented a disease relapse in close temporal association with their first AZD1222 vaccination dose against COVID-19. These patients had been stable for a median period of six years, with no evidence of disease activity and no change in their medication. After a median of 13 days (7 to 25 days) from vaccination, they developed a new relapse with increased disability and new lesions on magnetic resonance imaging. Although this association may be rare, it might be an adverse event of AZD1222.


Assuntos
COVID-19 , Esclerose Múltipla , Neuromielite Óptica , ChAdOx1 nCoV-19 , Humanos , Recidiva , SARS-CoV-2 , Vacinação
10.
Stem Cell Rev Rep ; 18(2): 609-625, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34453694

RESUMO

Mesenchymal stem cells comprise a natural reservoir of undifferentiated cells within adult tissues. Given their self-renewal, multipotency, regenerative potential and immunomodulatory properties, MSCs have been reported as a promising cell therapy for the treatment of different diseases, including neurodegenerative and autoimmune diseases. In this study, we investigated the immunomodulatory properties of human tubal mesenchymal stem cells (htMSCs) using the EAE model. htMSCs were able to suppress dendritic cells activation downregulating antigen presentation-related molecules, such as MHCII, CD80 and CD86, while impairing IFN-γ and IL-17 and increasing IL-10 and IL-4 secretion. It further correlated with milder disease scores when compared to the control group due to fewer leukocytes infiltrating the CNS, specially Th1 and Th17 lymphocytes, associated with increased IL-10 secreting Tr1 cells. Conversely, microglia were less activated and infiltrating mononuclear cells secreted higher levels of IL-4 and IL-10 and expressed reduced chemokine receptors as CCR4, CCR6 and CCR8. qPCR of the spinal cords revealed upregulation of indoleamine-2,3-dioxygenase (IDO) and brain derived neurotrophic factor (BDNF). Taken together, here evidenced the potential of htMSCs as an alternative for the treatment of inflammatory, autoimmune or neurodegenerative diseases.


Assuntos
Encefalomielite Autoimune Experimental , Células-Tronco Mesenquimais , Adulto , Animais , Sistema Nervoso Central , Encefalomielite Autoimune Experimental/terapia , Tubas Uterinas , Feminino , Humanos , Interleucina-10 , Interleucina-4
11.
Front Med (Lausanne) ; 8: 760170, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34901074

RESUMO

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection is caused by a respiratory virus with a wide range of manifestations, varying from asymptomatic to fatal cases, with a generally short outcome. However, some individuals present long-term viral shedding. We monitored 38 individuals who were mildly affected by the SARS-CoV-2 infection. Out of the total studied population, three (7.9%) showed atypical events regarding the duration of positivity for viral RNA detection. In one of these atypical cases, a previously HIV-positive male patient presented a SARS-CoV-2 RNA shedding and subgenomic RNA (sgRNA) detected from the upper respiratory tract, respectively, for 232 and 224 days after the onset of the symptoms. The SARS-CoV-2 B.1.1.28 lineage, one of the most prevalent in Brazil in 2020, was identified in this patient in three serial samples. Interestingly, the genomic analyses performed throughout the infectious process showed an increase in the genetic diversity of the B.1.1.28 lineage within the host itself, with viral clearance occurring naturally, without any intervention measures to control the infection. Contrasting widely spread current knowledge, our results indicate that potentially infectious SARS-CoV-2 virus might be shed by much longer periods by some infected patients. This data call attention to better adapted non-pharmacological measures and clinical discharge of patients aiming at preventing the spread of SARS-CoV-2 to the population.

12.
Viruses ; 13(11)2021 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-34834918

RESUMO

INTRODUCTION: ZIKV is a highly neurotropic virus that can cause the death of infected neuroprogenitor cells through mitochondrial damage and intrinsic apoptotic signaling. In this context, the role of reactive oxygen species (ROS) in neuronal cell death caused by ZIKV still remains elusive. OBJECTIVE: We aimed at evaluating the role of these cellular components in the death of human undifferentiated neuroblastoma cell line infected with ZIKV. RESULTS: ZIKV infection resulted in the extensive death of SH-SY5Y cells with the upregulation of several genes involved in survival and apoptotic responses as well as the colocalization of mitochondrial staining with ZIKV Envelope (E) protein. Notably, levels of intracellular reactive oxygen species (ROS) were not altered during ZIKV infection in undifferentiated SH-SY5Y cells, and consistent with these results, the treatment of infected cells with the widely studied ROS scavenger N-acetylcysteine (NAC) did not prevent cell death in these cells. CONCLUSION: Altogether, our results suggest that excessive ROS production is not the main trigger of SH-SY5Y cells death in ZIKV infection.


Assuntos
Apoptose , Neuroblastoma/fisiopatologia , Espécies Reativas de Oxigênio/metabolismo , Infecção por Zika virus/fisiopatologia , Zika virus/fisiologia , Linhagem Celular Tumoral , Humanos , Mitocôndrias/genética , Mitocôndrias/metabolismo , Neuroblastoma/metabolismo , Neuroblastoma/virologia , Estresse Oxidativo , Zika virus/genética , Infecção por Zika virus/metabolismo , Infecção por Zika virus/virologia
13.
Viruses ; 13(10)2021 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-34696422

RESUMO

Over the years, viral infections have caused severe illness in humans. Zika Virus (ZIKV) is a flavivirus transmitted by mosquito vectors that leads to notable neurological impairment, whose most dramatic impact is the Congenital ZIKV Syndrome (CZS). ZIKV targets neuronal precursor cells leading to apoptosis and further impairment of neuronal development, causing microcephaly, lissencephaly, ventriculomegaly, and calcifications. Several regulators of biological processes are involved in CZS development, and in this context, microRNAs (miRNAs) seem to have a fundamental role. miRNAs are important regulators of protein translation, as they form the RISC silencing complex and interact with complementary mRNA target sequences to further post-transcriptional repression. In this context, little is known about their participation in the pathogenesis of viral infections. In this review, we discuss how miRNAs could relate to ZIKV and other flavivirus infections.


Assuntos
MicroRNAs/genética , Infecção por Zika virus/genética , Infecção por Zika virus/patologia , Animais , Redes Reguladoras de Genes/genética , Humanos , Imunidade/genética , Imunidade/imunologia , MicroRNAs/metabolismo , Replicação Viral/genética , Zika virus/genética , Zika virus/patogenicidade , Zika virus/fisiologia , Infecção por Zika virus/virologia
14.
J Fungi (Basel) ; 7(9)2021 Sep 14.
Artigo em Inglês | MEDLINE | ID: mdl-34575795

RESUMO

Environmental factors, including infections, are strongly associated with the pathogenesis of multiple sclerosis (MS), which is an autoimmune and demyelinating disease of the central nervous system (CNS). Although classically associated with bacterial and viral agents, fungal species have also been suspected to affect the course of the disease. Candida tropicalis is an opportunistic fungus that affects immunocompromised individuals and is also able to spread to vital organs. As C. tropicalis has been increasingly isolated from systemic infections, we aimed to evaluate the effect of this fungus on experimental autoimmune encephalomyelitis (EAE), a murine model to study MS. For this, EAE was induced in female C57BL/6 mice 3 days after infection with 106 viable C. tropicalis yeasts. The infection decreased EAE prevalence and severity, confirmed by the less inflammatory infiltrate and less demyelization in the lumbar spinal cord. Despite this, C. tropicalis infection associated with EAE results in the death of some animals and increased urea and creatinine serum levels. The kidneys of EAE-infected mice showed higher fungal load associated with increased leukocyte infiltration (CD45+ cells) and higher expression of T-box transcription factor (Tbx21) and forkhead box P3 (Foxp3). Altogether, our results demonstrate that although C. tropicalis infection reduces the prevalence and severity of EAE, partially due to the sequestration of leukocytes by the inflamed renal tissue, this effect is associated with a poor disease outcome.

15.
PLoS Negl Trop Dis ; 15(8): e0009575, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34351896

RESUMO

Since the 2015 to 2016 outbreak in America, Zika virus (ZIKV) infected almost 900,000 patients. This international public health emergency was mainly associated with a significant increase in the number of newborns with congenital microcephaly and abnormal neurologic development, known as congenital Zika syndrome (CZS). Furthermore, Guillain-Barré syndrome (GBS), a neuroimmune disorder of adults, has also been associated with ZIKV infection. Currently, the number of ZIKV-infected patients has decreased, and most of the cases recently reported present as a mild and self-limiting febrile illness. However, based on its natural history of a typical example of reemerging pathogen and the lack of specific therapeutic options against ZIKV infection, new outbreaks can occur worldwide, demanding the attention of researchers and government authorities. Here, we discuss the clinical spectrum and immunopathological mechanisms underlying ZIKV-induced neurological manifestations. Several studies have confirmed the tropism of ZIKV for neural progenitor stem cells by demonstrating the presence of ZIKV in the central nervous system (CNS) during fetal development, eliciting a deleterious inflammatory response that compromises neurogenesis and brain formation. Of note, while the neuropathology of CZS can be due to a direct viral neuropathic effect, adults may develop neuroimmune manifestations such as GBS due to poorly understood mechanisms. Antiganglioside autoantibodies have been detected in multiple patients with ZIKV infection-associated GBS, suggesting a molecular mimicry. However, further additional immunopathological mechanisms remain to be uncovered, paving the way for new therapeutic strategies.


Assuntos
Encéfalo/embriologia , Síndrome de Guillain-Barré/virologia , Microcefalia/virologia , Infecção por Zika virus/patologia , Zika virus/patogenicidade , Animais , Encéfalo/virologia , Feminino , Síndrome de Guillain-Barré/etiologia , Humanos , Camundongos , Células-Tronco Neurais/virologia , Gravidez , Complicações Infecciosas na Gravidez , Infecção por Zika virus/virologia
16.
Brain Behav Immun ; 97: 260-274, 2021 10.
Artigo em Inglês | MEDLINE | ID: mdl-34390806

RESUMO

Zika virus (ZIKV) has the ability to cross placental and brain barriers, causing congenital malformations in neonates and neurological disorders in adults. However, the pathogenic mechanisms of ZIKV-induced neurological complications in adults and congenital malformations are still not fully understood. Gas6 is a soluble TAM receptor ligand able to promote flavivirus internalization and downregulation of immune responses. Here we demonstrate that there is a correlation between ZIKV neurological complications with higher Gas6 levels and the downregulation of genes associated with anti-viral response, as type I IFN due to Socs1 upregulation. Also, Gas6 gamma-carboxylation is essential for ZIKV invasion and replication in monocytes, the main source of this protein, which was inhibited by warfarin. Conversely, Gas6 facilitates ZIKV replication in adult immunocompetent mice and enabled susceptibility to transplacental infection. Our data indicate that ZIKV promotes the upregulation of its ligand Gas6, which contributes to viral infectivity and drives the development of severe adverse outcomes during ZIKV infection.


Assuntos
Doenças do Sistema Nervoso , Infecção por Zika virus , Zika virus , Animais , Feminino , Humanos , Camundongos , Placenta , Gravidez , Replicação Viral , Infecção por Zika virus/complicações
17.
Clin Sci (Lond) ; 135(9): 1065-1082, 2021 05 14.
Artigo em Inglês | MEDLINE | ID: mdl-33960391

RESUMO

Cellular therapy with mesenchymal stem cells (MSCs) is a huge challenge for scientists, as little translational relevance has been achieved. However, many studies using MSCs have proved their suppressive and regenerative capacity. Thus, there is still a need for a better understanding of MSCs biology and the establishment of newer protocols, or to test unexplored tissue sources. Here, we demonstrate that murine endometrial-derived MSCs (meMSCs) suppress Experimental Autoimmune Encephalomyelitis (EAE). MSC-treated animals had milder disease, with a significant reduction in Th1 and Th17 lymphocytes in the lymph nodes and in the central nervous system (CNS). This was associated with increased Il27 and Cyp1a1 expression, and presence of IL-10-secreting T CD4+ cells. At EAE peak, animals had reduced CNS infiltrating cells, histopathology and demyelination. qPCR analysis evidenced the down-regulation of several pro-inflammatory genes and up-regulation of indoleamine-2,3-dioxygenase (IDO). Consistently, co-culturing of WT and IDO-/- meMSCs with T CD4+ cells evidenced the necessity of IDO on the suppression of encephalitogenic lymphocytes, and IDO-/- meMSCs were not able to suppress EAE. In addition, WT meMSCs stimulated with IL-17A and IFN-γ increased IDO expression and secretion of kynurenines in vitro, indicating a negative feedback loop. Pathogenic cytokines were increased when CD4+ T cells from AhR-/- mice were co-cultured with WT meMSC. In summary, our research evidences the suppressive activity of the unexplored meMSCs population, and shows the mechanism depends on IDO-kynurenines-Aryl hydrocarbon receptor (AhR) axis. To our knowledge this is the first report evidencing that the therapeutic potential of meMSCs relying on IDO expression.


Assuntos
Encefalomielite Autoimune Experimental/terapia , Indolamina-Pirrol 2,3,-Dioxigenase/metabolismo , Transplante de Células-Tronco Mesenquimais , Animais , Encefalomielite Autoimune Experimental/enzimologia , Encefalomielite Autoimune Experimental/imunologia , Endométrio/citologia , Feminino , Ativação Linfocitária , Células-Tronco Mesenquimais/citologia , Células-Tronco Mesenquimais/fisiologia , Camundongos Endogâmicos C57BL , Linfócitos T/metabolismo
18.
Front Immunol ; 12: 624919, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33796100

RESUMO

Neuroinflammatory and neurodegenerative diseases are a major public health problem worldwide, especially with the increase of life-expectancy observed during the last decades. For many of these diseases, we still lack a full understanding of their etiology and pathophysiology. Nonetheless their association with mitochondrial dysfunction highlights this organelle as an important player during CNS homeostasis and disease. Markers of Parkinson (PD) and Alzheimer (AD) diseases are able to induce innate immune pathways induced by alterations in mitochondrial Ca2+ homeostasis leading to neuroinflammation. Additionally, exacerbated type I IFN responses triggered by mitochondrial DNA (mtDNA), failures in mitophagy, ER-mitochondria communication and mtROS production promote neurodegeneration. On the other hand, regulation of mitochondrial dynamics is essential for CNS health maintenance and leading to the induction of IL-10 and reduction of TNF-α secretion, increased cell viability and diminished cell injury in addition to reduced oxidative stress. Thus, although previously solely seen as power suppliers to organelles and molecular processes, it is now well established that mitochondria have many other important roles, including during immune responses. Here, we discuss the importance of these mitochondrial dynamics during neuroinflammation, and how they correlate either with the amelioration or worsening of CNS disease.


Assuntos
Encéfalo/metabolismo , Inflamação/metabolismo , Mitocôndrias/metabolismo , Dinâmica Mitocondrial , Doenças Neurodegenerativas/metabolismo , Neuroimunomodulação , Alarminas/metabolismo , Animais , Encéfalo/imunologia , Encéfalo/patologia , Citocinas/metabolismo , Humanos , Inflamação/imunologia , Inflamação/patologia , Mediadores da Inflamação/metabolismo , Mitocôndrias/imunologia , Mitocôndrias/patologia , Degeneração Neural , Doenças Neurodegenerativas/imunologia , Doenças Neurodegenerativas/patologia
19.
Adv Exp Med Biol ; 1321: 21-31, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33656710

RESUMO

The recently emerged coronavirus named severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), the causal agent of COVID-19, is the newest threat to human health. It has already infected more than 54.5 million people worldwide, currently leading to more than 1.3 million deaths. Although it causes a mild flu-like disease in most patients, lethality may increase to more than 20% in elderly subjects, especially in those with comorbidities, like hypertension, diabetes, or lung and cardiac disease, and the mechanisms are still elusive. Common symptoms at the onset of illness are fever, cough, myalgia or fatigue, headache, and diarrhea or constipation. Interestingly, respiratory viruses have also placed themselves as relevant agents for central nervous system (CNS) pathologies. Conversely, SARS-CoV-2 has already been detected in the cerebrospinal fluid. Here, we discuss several clinical features related to CNS infection during COVID-19. Patients may progress from headaches and migraines to encephalitis, stroke, and seizures with leptomeningitis. However, the pathway used by the virus to reach the brain is still unknown. It may infect the olfactory bulb by retrograde neuronal transportation from olfactory epithelium, or it could be transported by the blood. Either way, neurological complications of COVID-19 add greatly to the complex pathophysiology of the disease. Neurological signs and symptoms must alert physicians not only to worst outcomes but also to future possible degenerative diseases.


Assuntos
COVID-19 , Infecções por Coronavirus , Doenças do Sistema Nervoso , Idoso , Infecções por Coronavirus/epidemiologia , Humanos , Doenças do Sistema Nervoso/epidemiologia , Pandemias , SARS-CoV-2
20.
J Neuroimmunol ; 350: 577435, 2020 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-33189062

RESUMO

INTRODUCTION: Multiple Sclerosis (MS) is a chronic, autoimmune, demyelinating disease of the central nervous system (CNS). Currently, several protocols are described for the different phases of MS. In this longitudinal study, we aim to quantify the concentration of plasma cytokines of MS patients treated with Fingolimod alone or after Glatiramer Acetate (GA) or Interferon-beta (IFN-ß), in order to compeer both treatments and describes if it is possible to use them as biomarkers. OBJECTIVE: Compare the two different types of drug treatment and describes possible immune biomarkers in RRMS patients treated with Fingolimod alone or after GA or IFN-ß. MATERIALS AND METHODS: This is a controlled, non-randomized clinical trial. Plasma concentrations of IL-31, sCD40L and nine others cytokines were evaluated in two groups of patients with a one-year follow-up. Group 1 (n = 12): RRMS patients treated with GA or IFN-ß for at least six months before the study who changed therapy to Fingolimod after six months, and Group 2 (n = 12): naïve RRMS patients who started treatment with Fingolimod. We used ANOVA two-way to analyze the cytokines and Spearman coefficient to evaluate the correlation. RESULTS: Although Group 2 started with a greater number of relapses per disease duration, Fingolimod treatment was effective in decreasing this parameter, as well as EDSS over 12 months. However, the treatment with GA or IFN-ß on Group 1 showed a tendency to increase the number of relapses after 6 months of follow-up, which decrease when the therapy was changed to Fingolimod. After the evaluation of 11 cytokines in one year, we found that IL-31 and sCD40L were the biomarkers that demonstrated a more difference when compared to the classical ones, following the clinical pattern over the treatment period. CONCLUSIONS: Our study describes the existence of two promising plasmatic biomarkers (IL-31 and sCD40L), which reduced plasmatic levels in RRMS patients followed the treatment time of Fingolimod, despite that more studies are needed to prove their efficiency.

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