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It is both important and required to quickly and accurately detect chemical warfare agents, such as the highly toxic nerve agent sarin. Surface-enhanced Raman scattering (SERS) has received considerable attention due to its rapid results, high sensitivity, non-destructive data acquisition, and unique spectroscopic fingerprint. In this work, we successfully prepared SERS cotton swabs (CSs) for the detection of the sarin simulant agent dimethyl methyl phosphonate (DMMP) by anchoring N1-(3-trimethoxysilylpropyl) diethylenetriamine (ATS)/silver nanoparticle (AgNP) nanocomposites on CSs using ATS as the stabilizer and coupling agent. Simultaneously, the binding mode and reaction mechanics between the AgNP, ATS, and CS were confirmed by XPS. The modified CSs exhibited good uniformity, stability, and adsorption capability for SERS measurements, enabling the adsorption and detection of DMMP residue from an irregular surface via a simple swabbing process, with a detection limit of 1 g/L. The relative standard deviations (RSDs) of RSD710 = 5.6% had high reproducibility. In this research, the fabrication method could easily be extended to other cellulose compounds, such as natural fibers and paper. Furthermore, the versatile SERS CSs can be used for the on-site detection of DMMP, particularly in civil and defense applications, to guarantee food security and the health of the population.
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ß-thalassemia is associated with multiple hematological and cerebrovascular symptoms linked to a hypercoagulable state that has not been fully replicated in animal models for the development of stroke treatments. Herein we compared the physiological properties and responses to transient cerebral hypoxia-ischemia (tHI) between six-month-old wildtype and heterozygous Th3/+ mice, a model of non-transfusion-dependent ß-thalassemia intermedia (ß-TI). We found that Th3/+ mice developed microcytic anemia, splenomegaly, higher platelet counts, and increased platelet-erythrocyte plus erythrocyte-leukocyte aggregates. Furthermore, Th3/+ mice showed diminished cerebrovascular reactivity (CVR) and cortical oxygen saturation under repetitive hypercapnic challenges. When subjected to a sub-threshold tHI insult, platelets and leukocytes in Th3/+ mice adhered to the cerebrovascular wall or formed aggregates, while their counterparts flew through smoothly in wildtype mice. Subsequently, Th3/+ mice showed increased fibrin deposition around cerebral blood vessels and larger infarction than wildtype mice, especially in female Th3/+ mice. Collectively these results showed that Th3/+ mice mimic key clinical features and a propensity to thromboembolism in ß-TI patients. The hypercoagulable state in Th3/+ mice is likely caused by multiple hematological and CVR anomalies that are similar, but are not identical to those in the mouse model of sickle cell anemia. As such, we suggest that Th3/+ mice are a useful model to study the pathological mechanisms and prophylactic stroke treatments in thalassemia patients.
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Hipóxia-Isquemia Encefálica , Acidente Vascular Cerebral , Talassemia beta , Animais , Modelos Animais de Doenças , Feminino , Hipóxia-Isquemia Encefálica/complicações , Camundongos , Acidente Vascular Cerebral/complicações , Talassemia beta/complicações , Talassemia beta/patologiaRESUMO
A copper-catalyzed cascade reaction of α-diazocarbonyl compounds with ethenesulfonyl fluoride (ESF) is developed, affording a variety of highly functionalized pyrazolyl aliphatic sulfonyl fluorides in good to excellent yields (66-98%). This transformation features broad substrates, exclusive regioselectivity, high atom economy and operational simplicity, thus providing a straightforward method for the direct construction of pyrazole-containing aliphatic sulfonyl fluorides, which will provide great applicable value in medicinal chemistry and other related disciplines.
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Fluoretos , Ácidos Sulfínicos , Química Farmacêutica , Fluoretos/química , Pirazóis , Ácidos Sulfínicos/químicaRESUMO
Growing evidence suggests that early-life interactions among genetic, immune, and environment factors may modulate neurodevelopment and cause psycho-cognitive deficits. Maternal immune activation (MIA) induces autism-like behaviors in offspring, but how it interplays with perinatal brain injury (especially birth asphyxia or hypoxia ischemia [HI]) is unclear. Herein we compared the effects of MIA (injection of poly[I:C] to dam at gestational day 12.5), HI at postnatal day 10, and the combined MIA/HI insult in murine offspring of both sexes. We found that MIA induced autistic-like behaviors without microglial activation but amplified post-HI NFκB signaling, pro-inflammatory responses, and brain injury in offspring. Conversely, HI neither provoked autistic-like behaviors nor concealed them in the MIA offspring. Instead, the dual MIA/HI insult added autistic-like behaviors with diminished synaptic density and reduction of autism-related PSD-95 and Homer-1 in the hippocampus, which were missing in the singular MIA or HI insult. Further, the dual MIA/HI insult enhanced the brain influx of Otx2-positive monocytes that are associated with an increase of perineuronal net-enwrapped parvalbumin neurons. Using CCR2-CreER mice to distinguish monocytes from the resident microglia, we found that the monocytic infiltrates gradually adopted a ramified morphology and expressed the microglial signature genes (Tmem119, P2RY12, and Sall1) in post-MIA/HI brains, with some continuing to express the proinflammatory cytokine TNFα. Finally, genetic or pharmacological obstruction of monocytic influx significantly reduced perineuronal net-enwrapped parvalbumin neurons and autistic-like behaviors in MIA/HI offspring. Together, these results suggest a pathologic role of monocytes in the two-hit (immune plus neonatal HI) model of neurodevelopmental defects.SIGNIFICANCE STATEMENT In autism spectrum disorders (ASDs), prenatal infection or maternal immune activation (MIA) may act as a primer for multiple genetic and environmental factors to impair neurodevelopment. This study examined whether MIA cooperates with neonatal cerebral hypoxia ischemia to promote ASD-like aberrations in mice using a novel two-hit model. It was shown that the combination of MIA and neonatal hypoxia ischemia produces autistic-like behaviors in the offspring, and has synergistic effects in inducing neuroinflammation, monocytic infiltrates, synaptic defects, and perineuronal nets. Furthermore, genetic or pharmacological intervention of the MCP1-CCR2 chemoattractant pathway markedly reduced monocytic infiltrates, perineuronal nets, and autistic-like behaviors. These results suggest reciprocal escalation of immune and neonatal brain injury in a subset of ASD that may benefit from monocyte-targeted treatments.
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Transtorno Autístico/imunologia , Transtorno Autístico/psicologia , Comportamento Animal , Deficiências do Desenvolvimento/imunologia , Deficiências do Desenvolvimento/psicologia , Monócitos/imunologia , Animais , Isquemia Encefálica/genética , Isquemia Encefálica/psicologia , Feminino , Ativação de Macrófagos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Microglia/imunologia , NF-kappa B , Parvalbuminas/genética , Poli I-C , Densidade Pós-Sináptica , Gravidez , Transdução de Sinais , Comportamento SocialRESUMO
Hypoxia-inducible factor-1α (HIF1α) is a major regulator of cellular adaptation to hypoxia and oxidative stress, and recent advances of prolyl-4-hydroxylase (P4H) inhibitors have produced powerful tools to stabilize HIF1α for clinical applications. However, whether HIF1α provokes or resists neonatal hypoxic-ischemic (HI) brain injury has not been established in previous studies. We hypothesize that systemic and brain-targeted HIF1α stabilization may have divergent effects. To test this notion, herein we compared the effects of GSK360A, a potent P4H inhibitor, in in-vitro oxygen-glucose deprivation (OGD) and in in-vivo neonatal HI via intracerebroventricular (ICV), intraperitoneal (IP), and intranasal (IN) drug-application routes. We found that GSK360A increased the erythropoietin (EPO), heme oxygenase-1 (HO1) and glucose transporter 1 (Glut1) transcripts, all HIF1α target-genes, and promoted the survival of neurons and oligodendrocytes after OGD. Neonatal HI insult stabilized HIF1α in the ipsilateral hemisphere for up to 24 h, and either ICV or IN delivery of GSK360A after HI increased the HIF1α target-gene transcripts and decreased brain damage. In contrast, IP-injection of GSK360A failed to reduce HI brain damage, but elevated the risk of mortality at high doses, which may relate to an increase of the kidney and plasma EPO, leukocytosis, and abundant vascular endothelial growth factor (VEGF) mRNAs in the brain. These results suggest that brain-targeted HIF1α-stabilization is a potential treatment of neonatal HI brain injury, while systemic P4H-inhibition may provoke unwanted adverse effects.
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Inibidores Enzimáticos/farmacologia , Glicina/análogos & derivados , Subunidade alfa do Fator 1 Induzível por Hipóxia/efeitos dos fármacos , Prolina Dioxigenases do Fator Induzível por Hipóxia/antagonistas & inibidores , Hipóxia-Isquemia Encefálica/metabolismo , Neurônios/efeitos dos fármacos , Oligodendroglia/efeitos dos fármacos , Quinolonas/farmacologia , Administração Intranasal , Animais , Animais Recém-Nascidos , Sobrevivência Celular/efeitos dos fármacos , Eritropoetina/genética , Transportador de Glucose Tipo 1/efeitos dos fármacos , Transportador de Glucose Tipo 1/genética , Glicina/farmacologia , Heme Oxigenase (Desciclizante)/efeitos dos fármacos , Heme Oxigenase (Desciclizante)/genética , Subunidade alfa do Fator 1 Induzível por Hipóxia/metabolismo , Injeções Intraperitoneais , Injeções Intraventriculares , Neurônios/metabolismo , Oligodendroglia/metabolismo , RatosRESUMO
Vascular leakage is one of the salient characteristics of severe dengue. Nonstructural protein 1 (NS1) of dengue virus (DENV) can stimulate endothelial cells to secrete endothelial hyperpermeability factor, macrophage migration inhibitory factor (MIF), and the glycocalyx degradation factor heparanase 1 (HPA-1). However, it is unclear whether MIF is directly involved in NS1-induced glycocalyx degradation. In this study, we observed that among NS1, MIF and glycocalyx degradation-related molecules, the HPA-1, metalloproteinase 9 (MMP-9) and syndecan 1 (CD138) serum levels were all increased in dengue patients, and only NS1 and MIF showed a positive correlation with the CD138 level in severe patients. To further characterize and clarify the relationship between MIF and CD138, we used recombinant NS1 to stimulate human cells in vitro and challenge mice in vivo. Our tabulated results suggested that NS1 stimulation could induce human endothelial cells to secrete HPA-1 and immune cells to secrete MMP-9, resulting in endothelial glycocalyx degradation and hyperpermeability. Moreover, HPA-1, MMP-9, and CD138 secretion after NS1 stimulation was blocked by MIF inhibitors or antibodies both in vitro and in mice. Taken together, these results suggest that MIF directly engages in dengue NS1-induced glycocalyx degradation and that targeting MIF may represent a possible therapeutic approach for preventing dengue-induced vascular leakage.
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Vírus da Dengue/isolamento & purificação , Células Endoteliais/virologia , Glicocálix/virologia , Fatores Inibidores da Migração de Macrófagos/metabolismo , Animais , Permeabilidade Capilar/fisiologia , Linhagem Celular/virologia , Dengue/imunologia , Vírus da Dengue/imunologia , Células Endoteliais/metabolismo , Humanos , Oxirredutases Intramoleculares/metabolismo , Camundongos Transgênicos , Proteínas não Estruturais Virais/metabolismoRESUMO
Dengue virus (DENV) infection is the most common mosquito-transmitted viral infection. DENV infection can cause mild dengue fever or severe dengue hemorrhagic fever (DHF)/dengue shock syndrome (DSS). Hemorrhage and vascular leakage are two characteristic symptoms of DHF/DSS. However, due to the limited understanding of dengue pathogenesis, no satisfactory therapies to treat nor vaccine to prevent dengue infection are available, and the mortality of DHF/DSS is still high. DENV nonstructural protein 1 (NS1), which can be secreted in patients' sera, has been used as an early diagnostic marker for dengue infection for many years. However, the roles of NS1 in dengue-induced vascular leakage were described only recently. In this article, the pathogenic roles of DENV NS1 in hemorrhage and vascular leakage are reviewed, and the possibility of using NS1 as a therapeutic target and vaccine candidate is discussed.
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Vírus da Dengue/genética , Dengue Grave/prevenção & controle , Vacinas/uso terapêutico , Proteínas não Estruturais Virais/genética , Anticorpos Antivirais/uso terapêutico , Vírus da Dengue/imunologia , Vírus da Dengue/patogenicidade , Humanos , Dengue Grave/imunologia , Dengue Grave/virologia , Vacinas/imunologia , Proteínas não Estruturais Virais/imunologia , Proteínas não Estruturais Virais/uso terapêuticoRESUMO
DNA damage response (DDR) pathways are critical for ensuring that replication stress and various types of DNA lesion do not perturb production of neural cells during development. Cdk12 maintains genomic stability by regulating expression of DDR genes. Mutant mice in which Cdk12 is conditionally deleted in neural progenitor cells (NPCs) die after birth and exhibit microcephaly with a thinner cortical plate and an aberrant corpus callosum. We show that NPCs of mutant mice accumulate at G2 and M phase, and have lower expression of DDR genes, more DNA double-strand breaks and increased apoptosis. In addition to there being fewer neurons, there is misalignment of layers IV-II neurons and the presence of abnormal axonal tracts of these neurons, suggesting that Cdk12 is also required for the migration of late-arising cortical neurons. Using in utero electroporation, we demonstrate that the migrating mutant cells remain within the intermediate zone and fail to adopt a bipolar morphology. Overexpression of Cdk5 brings about a partially restoration of the neurons reaching layers IV-II in the mutant mice. Thus, Cdk12 is crucial to the repair of DNA damage during the proliferation of NPCs and is also central to the proper migration of late-arising neurons.
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Movimento Celular/fisiologia , Córtex Cerebral/crescimento & desenvolvimento , Córtex Cerebral/metabolismo , Quinases Ciclina-Dependentes/metabolismo , Neurogênese/fisiologia , Neurônios/metabolismo , Animais , Proliferação de Células/fisiologia , Córtex Cerebral/patologia , Quinase 5 Dependente de Ciclina/metabolismo , Quinases Ciclina-Dependentes/genética , Dano ao DNA/fisiologia , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Microcefalia/metabolismo , Microcefalia/patologia , Células-Tronco Neurais/metabolismo , Células-Tronco Neurais/patologia , Neurônios/patologia , Tamanho do Órgão , RNA Mensageiro/metabolismo , Fatores de TempoRESUMO
Amyloid self-assembly is linked to the pathogenesis of Alzheimer's disease (AD) and typeâ 2 diabetes (T2D), but so far, no anti-amyloid compound has reached the clinic. Macrocyclic peptides belong to the most attractive drug candidates. Herein we present macrocyclic peptides (MCIPs) designed using minimal IAPP-derived recognition elements as a novel class of nanomolar amyloid inhibitors of both Aß40(42) and IAPP or Aß40(42) alone and show that chirality controls inhibitor selectivity. Sequence optimization led to the discovery of an Aß40(42)-selective MCIP exhibiting high proteolytic stability in human plasma and human blood-brain barrier (BBB) crossing ability in a cell model, two highly desirable properties for anti-amyloid AD drugs. Owing to their favorable properties, MCIPs should serve as leads for macrocyclic peptide-based anti-amyloid drugs and scaffolds for the design of small-molecule peptidomimetics for targeting amyloidogenesis in AD or in both AD and T2D.
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Amiloide/antagonistas & inibidores , Compostos Macrocíclicos/química , Compostos Macrocíclicos/farmacologia , Nanotecnologia , Peptídeos/química , Peptídeos/farmacologia , Sequência de AminoácidosRESUMO
Dengue virus (DENV) infection is the most common cause of viral hemorrhagic fever, which can lead to life-threatening dengue hemorrhagic fever/dengue shock syndrome (DHF/DSS). Hemorrhage and plasma leakage are two major hallmarks of DHF/DSS. Because the mechanisms causing these pathogenic changes are unclear, there is no effective therapy against DHF/DSS. In this review, we focus on the possible pathogenic effects of a pleiotropic cytokine, macrophage migration inhibitory factor (MIF), on the pathogenesis of DENV infection. MIF is a critical mediator of the host immune response and inflammation, and there is a correlation between the serum levels of MIF and disease severity in dengue patients. Furthermore, MIF knock-out mice exhibit less severe clinical disease and lethality. However, the role of MIF in the pathogenesis of DHF/DSS is not limited to immune cell recruitment. Recent evidence indicates that DENV infection induced MIF production and may contribute to vascular hyperpermeability and viral replication during DENV infection. The expression of both adhesion and coagulation molecules on MIF-stimulated monocytes and endothelial cells is also increased, which may contribute to inflammatory and anticoagulatory states during DHF/DSS. Therefore, blocking MIF production or its function may provide a solution for the treatment and prevention of DHF/DSS.
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Dengue/etiologia , Oxirredutases Intramoleculares/fisiologia , Fatores Inibidores da Migração de Macrófagos/fisiologia , Animais , Permeabilidade Capilar , Dengue/imunologia , Vírus da Dengue/fisiologia , Humanos , Inflamação/etiologia , Molécula 1 de Adesão Intercelular/análise , Oxirredutases Intramoleculares/química , Fatores Inibidores da Migração de Macrófagos/química , Camundongos , Replicação ViralRESUMO
Immune cell phenotyping frequently detects lineage-unrelated receptors. Here, we report that surface receptors can be transferred from primary macrophages to CD4 T cells and identify the Fcγ receptor CD32 as driver and cargo of this trogocytotic transfer. Filamentous CD32+ nanoprotrusions deposit distinct plasma membrane patches onto target T cells. Transferred receptors confer cell migration and adhesion properties, and macrophage-derived membrane patches render resting CD4 T cells susceptible to infection by serving as hotspots for HIV-1 binding. Antibodies that recognize T cell epitopes enhance CD32-mediated trogocytosis. Such autoreactive anti-HIV-1 envelope antibodies can be found in the blood of HIV-1 patients and, consistently, the percentage of CD32+ CD4 T cells is increased in their blood. This CD32-mediated, antigen-independent cell communication mode transiently expands the receptor repertoire and functionality of immune cells. HIV-1 hijacks this mechanism by triggering the generation of trogocytosis-promoting autoantibodies to gain access to immune cells critical to its persistence.
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Infecções por HIV , Soropositividade para HIV , HIV-1 , Humanos , Linfócitos T CD4-Positivos , Receptores de IgG/metabolismo , Autoanticorpos/metabolismo , TrogocitoseRESUMO
Dengue virus (DENV) infection can cause life-threatening dengue hemorrhagic fever (DHF) and dengue shock syndrome (DSS). Vascular leakage and abnormal hemorrhage are the two major pathogenic changes found in these patients. From previous studies, it is known that both antibodies and cytokines induced in response to DENV infection are involved in the immunopathogenesis of DHF/DSS. However, the role of viral factors during DENV infection remains unclear. Nonstructural protein 1 (NS1), which is secreted in the sera of patients, is a useful diagnostic marker for acute DENV infection. Nevertheless, the roles of NS1 and its antibodies in the pathogenesis of DHF/DSS are unclear. The focus of this review is to evaluate the possible contributions of NS1 and the antibodies it induces to vascular leakage and abnormal hemorrhage during DENV infection, which may provide clues to better understanding the pathogenesis of DHF/DSS.
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Anticorpos Antivirais/imunologia , Vírus da Dengue/patogenicidade , Dengue/virologia , Proteínas não Estruturais Virais/metabolismo , Anticorpos Antivirais/sangue , Dengue/imunologia , Dengue/metabolismo , Vírus da Dengue/imunologia , Vírus da Dengue/metabolismo , Humanos , Dengue Grave/imunologia , Dengue Grave/metabolismo , Dengue Grave/virologiaRESUMO
Objectives: To examine the effect and potential mechanism of electroacupuncture (EA) pretreatment in spatial learning, memory, gut microbiota, and JNK signaling in D-galactose-induced AD-like rats. Materials and Methods: The AD-like rat model was generated by intraperitoneal injection of D-galactose. Morris water maze was used to determine spatial learning and memory ability, Real-time PCR to determine intestinal flora levels, ELISA to determine tryptophan (Trp) and 5-HT levels in the colon and hippocampal tissues, immunofluorescence to determine 5-HT levels in enterochromaffin cells (ECs), and immunoblotting to determine JNK signaling protein levels in hippocampal tissues. Results: Electroacupuncture pretreatment significantly reduced escape latency and prolonged exploration time in the target quadrant, and significantly increased the relative DNA abundance of Lactobacillus and Bifidobacterium. Meanwhile, electroacupuncture pretreatment also reduced colonic 5-HT levels and increased hippocampal 5-HT levels. Moreover, electroacupuncture pretreatment significantly inhibited hippocampal JNK pathway-related protein expression, including 5-HT6R, JNK, p-JUNK, c-JUN, and p-c-Jun. And the combination of GV20 and ST36 was more effective than single acupoints. Conclusion: Electroacupuncture pretreatment improved the learning and memory ability of D-galactose-induced AD-like model rats, changed the gut microbiota composition, and the mechanism may be related to the gut-brain axis and the JNK signaling pathway. In addition, the combination of GV20 and ST36 could further enhance the efficacy.
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Abnormal phosphorylation of the microtubule-binding protein tau in the brain is a key pathological marker for Alzheimer's disease and additional neurodegenerative tauopathies. However, how hyperphosphorylated tau causes cellular dysfunction or death that underlies neurodegeneration remains an unsolved question critical for the understanding of disease mechanism and the design of efficacious drugs. Using a recombinant hyperphosphorylated tau protein (p-tau) synthesized by the PIMAX approach, we examined how cells responded to the cytotoxic tau and explored means to enhance cellular resistance to tau attack. Upon p-tau uptake, the intracellular calcium levels rose promptly. Gene expression analyses revealed that p-tau potently triggered endoplasmic reticulum (ER) stress, unfolded protein response (UPR), ER stress-associated apoptosis, and pro-inflammation in cells. Proteomics studies showed that p-tau diminished heme oxygenase-1 (HO-1), an ER stress-associated anti-inflammation and anti-oxidative stress regulator, while stimulated the accumulation of MIOS and other proteins. p-Tau-induced ER stress-associated apoptosis and pro-inflammation are ameliorated by apomorphine, a brain-permeable prescription drug widely used to treat Parkinson's disease symptoms, and by overexpression of HO-1. Our results reveal probable cellular functions targeted by hyperphosphorylated tau. Some of these dysfunctions and stress responses have been linked to neurodegeneration in Alzheimer's disease. The observations that the ill effects of p-tau can be mitigated by a small compound and by overexpressing HO-1 that is otherwise diminished in the treated cells inform new directions of Alzheimer's disease drug discovery.
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Background: Abnormal phosphorylation of the microtubule-binding protein tau in the brain is a key pathological marker for Alzheimer's disease and additional neurodegenerative tauopathies. However, how hyperphosphorylated tau causes cellular dysfunction or death that underlie neurodegeneration remains an unsolved question critical for the understanding of disease mechanism and the design of efficacious drugs. Methods: Using a recombinant hyperphosphorylated tau protein (p-tau) synthesized by the PIMAX approach, we examined how cells responded to the cytotoxic tau and explored means to enhance cellular resistance to tau attack. Results: Upon p-tau uptake, the intracellular calcium levels rose promptly. Gene expression analyses revealed that p-tau potently triggered endoplasmic reticulum (ER) stress, Unfolded Protein Response (UPR), ER stress-associated apoptosis, and pro-inflammation in cells. Proteomics studies showed that p-tau diminished heme oxygenase-1 (HO-1), an ER stress associated anti-inflammation and anti-oxidative stress regulator, while stimulated the accumulation of MIOS and other proteins. P-tau-induced ER stress-associated apoptosis and pro-inflammation are ameliorated by apomorphine, a brain-permeable prescription drug widely used to treat Parkinson's disease symptoms, and by overexpression of HO-1. Conclusion: Our results reveal probable cellular functions targeted by hyperphosphorylated tau. Some of these dysfunctions and stress responses have been linked to neurodegeneration in Alzheimer's disease. The observations that the ill effects of p-tau can be mitigated by a small compound and by overexpressing HO-1 that is otherwise diminished in the treated cells inform new directions of Alzheimer's disease drug discovery.
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Rationale: Monocytes belong to the mononuclear phagocyte system and are immune responders to tissue injury and infection. There were also reports of monocytes transforming to microglia-like cells. Here we explore the roles of monocytes in microglia ontogeny and the pathogenesis of neonatal cerebral hypoxic-ischemic (HI) brain injury in mice. Methods: We used three genetic methods to track the development of monocytes, including CX3CR1GFP/+; CCR2RFP/+ reporter mice, adoptive transfer of GFP+ monocytes, and fate-mapping with CCR2-CreER mice, in neonatal mouse brains with or without lipopolysaccharide (LPS, 0.3 mg/kg)-sensitized Vannucci HI. We also used genetic (CCR2RFP/ RFP, CCR2 knockout) and pharmacological methods (RS102895, a CCR2 antagonist) to test the roles of monocytic influx in LPS/HI brain injury. Results: CCR2+ monocytes entered the late-embryonic brains via choroid plexus, but rapidly became CX3CR1+ amoeboid microglial cells (AMCs). The influx of CCR2+ monocytes declined after birth, but recurred after HI or LPS-sensitized HI (LPS/HI) brain injury, particularly in the hippocampus. The CCR2-CreER-based fate-mapping showed that CCR2+ monocytes became CD68+ TNFα+ macrophages within 4 d after LPS/HI, and maintained as TNFα+ MHCII+ macrophages or persisted as Tmem119+ Sall1+ P2RY12+ ramified microglia for at least five months after injury. Genetic deletion of the chemokine receptor CCR2 markedly diminished monocytic influx, the expression of pro- and anti-inflammatory cytokines, and brain damage. Post-LPS/HI application of RS102895 also reduced inflammatory responses and brain damage, leading to better cognitive functions. Conclusion: These results suggest that monocytes promote acute inflammatory responses and may become pathological microglia long after the neonatal LPS/HI insult. Further, blocking the influx of monocytes may be a potential therapy for neonatal brain injury.
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Lesões Encefálicas/patologia , Hipóxia-Isquemia Encefálica/patologia , Microglia/patologia , Monócitos/imunologia , Doenças Neuroinflamatórias/patologia , Transferência Adotiva , Animais , Animais Recém-Nascidos , Movimento Celular , Células Cultivadas , Plexo Corióideo/citologia , Plexo Corióideo/imunologia , Feminino , Inflamação/patologia , Masculino , Camundongos Endogâmicos C57BL , Monócitos/transplante , Doenças Neuroinflamatórias/imunologia , Receptores CCR2/genética , Receptores CCR2/metabolismoRESUMO
Chronic lymphocytic leukemia (CLL) is characterized by the accumulation of small, mature CD5+ B lymphocytes in the blood, marrow, and lymphoid organs. Cell survival depends on interaction with the leukemic microenvironment. However, the mechanisms controlling CLL cell survival are still incompletely understood. Macrophage migration-inhibitory factor (MIF), a pro-inflammatory and immunoregulatory chemokine-like cytokine, interacts with CXCR4, a major chemokine receptor, as well as with CD74/invariant chain, a single-pass type II receptor. In this study, we analyzed the roles of CXCR4, CD74, and MIF in CLL. Mononuclear cells from patients with hematological malignancies were analyzed for coexpression of CXCR4 and CD74 by flow cytometry. Strong co- and overexpression of CXCR4 and CD74 were observed on B cells of CLL patients (n = 10). Survival and chemotaxis assays indicated that CXCR4 and CD74 work together to enhance the survival and migration of malignant cells in CLL. Blockade of the receptors, either individually or in combination, promoted cell death and led to an abrogation of MIF-driven migration responses in murine and human CLL cells, suggesting that joint activation of both receptors is crucial for CLL cell survival and mobility. These findings indicate that the MIF/CXCR4/CD74 axis represents a novel therapeutic target in CLL.
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Leucemia Linfocítica Crônica de Células B , Humanos , Camundongos , Animais , Leucemia Linfocítica Crônica de Células B/patologia , Sobrevivência Celular , Antígenos de Diferenciação de Linfócitos B/metabolismo , Antígenos de Histocompatibilidade Classe II/metabolismo , Receptores CXCR4/genética , Receptores CXCR4/metabolismo , Macrófagos/metabolismo , Microambiente TumoralRESUMO
Purpose: University freshmen are particularly vulnerable as they are undergoing the transition from high school to university with a range of changes. Sleep problems among this group in the Qinghai-Tibet Plateau of China were barely studied. This study aimed to explore sleep disturbance, and its association with quality of life (QoL) and demographic and clinical characteristics among university freshmen in Qinghai-Tibet Plateau, China. Methods: A multistage stratified cluster random sampling method was performed to recruit student participants with a structured questionnaire to collect sociodemographic and clinical characteristics, and lifestyle behaviors. Sleep disturbance including three aspects of sleep disturbance (i.e., difficulty initiating sleep (DIS), difficulty maintaining sleep (DMS), and early morning awakening (EMA)) was assessed using standardized measurement. Multiple logistic regression models were applied to analyze the data. Results: Among included 2,769 freshmen, the prevalence of sleep disturbance was 14.8% (95% CI: 14.2-15.5%), and corresponding prevalence of DIS, DMS, and EMA was 8.2% (95% CI: 7.7-8.7%), 8.3% (95% CI: 7.8-8.8%), and 4.2% (95% CI: 3.8-4.6%), respectively. Freshmen with sleeping disturbance had significantly lower QoL in physical [F (1, 2769) = 60.23, p < 0.001], psychological [F (1, 2769) = 46.18, p < 0.001], social [F (1, 2769) = 23.04, p < 0.001], and environment [F (1, 2769) = 6.07, p = 0.01] domains. Multiple logistic regression analyses revealed that having breakfast five times a week or less (less than three times, OR = 1.79, 95% CI: 1.34-2.40; 3-5 times, OR = 1.40, 95% CI: 1.09-1.79), self-perceived severe Internet dependence (OR = 1.71, 95% CI: 1.11-2.65), self-perceived poor health status (OR = 3.44, 95% CI: 2.06-5.74), high academic stress (OR = 1.42, 95% CI: 1.13-1.78), poor relationship with classmates (OR = 3.44, 95% CI: 1.53-7.71), and severe ADHD symptoms (OR = 1.08, 95% CI: 1.05-1.12) were positively associated with sleeping disturbance. Conclusion: Sleep disturbance was common among freshmen and is associated with poorer QoL. Prevention and intervention strategies should be developed and implemented, especially among the vulnerable university freshman groups.
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The creatine transporter (CrT) maintains brain creatine (Cr) levels, but the effects of its deficiency on energetics adaptation under stress remain unclear. There are also no effective treatments for CrT deficiency, the second most common cause of X-linked intellectual disabilities. Herein, we examined the consequences of CrT deficiency in brain energetics and stress-adaptation responses plus the effects of intranasal Cr supplementation. We found that CrT-deficient (CrT-/y) mice harbored dendritic spine and synaptic dysgenesis. Nurtured newborn CrT-/y mice maintained baseline brain ATP levels, with a trend toward signaling imbalance between the p-AMPK/autophagy and mTOR pathways. Starvation elevated the signaling imbalance and reduced brain ATP levels in P3 CrT-/y mice. Similarly, CrT-/y neurons and P10 CrT-/y mice showed an imbalance between autophagy and mTOR signaling pathways and greater susceptibility to cerebral hypoxia-ischemia and ischemic insults. Notably, intranasal administration of Cr after cerebral ischemia increased the brain Cr/N-acetylaspartate ratio, partially averted the signaling imbalance, and reduced infarct size more potently than intraperitoneal Cr injection. These findings suggest important functions for CrT and Cr in preserving the homeostasis of brain energetics in stress conditions. Moreover, intranasal Cr supplementation may be an effective treatment for congenital CrT deficiency and acute brain injury.
Assuntos
Encefalopatias Metabólicas Congênitas/genética , Encéfalo/metabolismo , Creatina/deficiência , DNA/genética , Proteínas de Membrana Transportadoras/genética , Deficiência Intelectual Ligada ao Cromossomo X/genética , Mutação , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/deficiência , Animais , Animais Recém-Nascidos , Encéfalo/ultraestrutura , Encefalopatias Metabólicas Congênitas/metabolismo , Encefalopatias Metabólicas Congênitas/patologia , Creatina/genética , Creatina/metabolismo , Análise Mutacional de DNA , Modelos Animais de Doenças , Homeostase , Masculino , Proteínas de Membrana Transportadoras/deficiência , Deficiência Intelectual Ligada ao Cromossomo X/metabolismo , Deficiência Intelectual Ligada ao Cromossomo X/patologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Mutantes , Microscopia Eletrônica , Neurônios/metabolismo , Neurônios/ultraestrutura , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/genética , Proteínas da Membrana Plasmática de Transporte de Neurotransmissores/metabolismoRESUMO
Microglia are brain-resident immune cells with a repertoire of functions in the brain. However, the extent of their interactions with the vasculature and potential regulation of vascular physiology has been insufficiently explored. Here, we document interactions between ramified CX3CR1 + myeloid cell somata and brain capillaries. We confirm that these cells are bona fide microglia by molecular, morphological and ultrastructural approaches. Then, we give a detailed spatio-temporal characterization of these capillary-associated microglia (CAMs) comparing them with parenchymal microglia (PCMs) in their morphological activities including during microglial depletion and repopulation. Molecularly, we identify P2RY12 receptors as a regulator of CAM interactions under the control of released purines from pannexin 1 (PANX1) channels. Furthermore, microglial elimination triggered capillary dilation, blood flow increase, and impaired vasodilation that were recapitulated in P2RY12-/- and PANX1-/- mice suggesting purines released through PANX1 channels play important roles in activating microglial P2RY12 receptors to regulate neurovascular structure and function.