RESUMEN
Blood-brain barrier (BBB) injury and dysfunction following infection with the human immunodeficiency virus (HIV) enables viral entry into the brain, infection of resident brain cells, neuronal injury and subsequent neurodegeneration leading to HIV-associated neurocognitive disorders (HAND). Although combination antiretroviral therapy has significantly reduced the incidence and prevalence of acquired immunodeficiency syndrome and increased the life expectancy of people living with HIV, the prevalence of HAND remains high. With aging of people living with HIV associated with increased comorbidities, the prevalence of HIV-related central nervous system (CNS) complications is expected to remain high. Considering the principal role of the brain endothelium in HIV infection of the CNS and HAND, the purpose of this manuscript is to review the current literature on the pathobiology of the brain endothelium structural and functional dysregulation in HIV infection, including in the presence of HIV-1 and viral proteins (gp120, Tat, Nef, and Vpr). We summarize evidence from human and animal studies, in vitro studies, and associated mechanisms. We further summarize evidence of synergy or lack thereof between commonly abused substances (cocaine, methamphetamine, alcohol, tobacco, opioids, and cannabinoids) and HIV- or viral protein-induced BBB injury and dysfunction.
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Barrera Hematoencefálica , Encéfalo , Infecciones por VIH , Trastornos Relacionados con Sustancias , Humanos , Infecciones por VIH/patología , Infecciones por VIH/complicaciones , Trastornos Relacionados con Sustancias/patología , Trastornos Relacionados con Sustancias/complicaciones , Trastornos Relacionados con Sustancias/metabolismo , Encéfalo/patología , Encéfalo/metabolismo , Encéfalo/virología , Barrera Hematoencefálica/patología , Barrera Hematoencefálica/metabolismo , Animales , Endotelio/patología , Endotelio/metabolismo , VIH-1RESUMEN
Alzheimer's disease (AD) is the most common cause of dementia, characterized by memory loss, cognitive decline, personality changes, and various neurological symptoms. The role of blood-brain barrier (BBB) injury, extracellular matrix (ECM) abnormalities, and oligodendrocytes (ODCs) dysfunction in AD has gained increasing attention, yet the detailed pathogenesis remains elusive. This study integrates single-cell sequencing of AD patients' cerebrovascular system with a genome-wide association analysis. It aims to elucidate the associations and potential mechanisms behind pericytes injury, ECM disorder, and ODCs dysfunction in AD pathogenesis. Finally, we identified that abnormalities in the pericyte PI3K-AKT-FOXO signaling pathway may be involved in the pathogenic process of AD. This comprehensive approach sheds new light on the complex etiology of AD and opens avenues for advanced research into its pathogenesis and therapeutic strategies.
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Enfermedad de Alzheimer , Barrera Hematoencefálica , Estudio de Asociación del Genoma Completo , Pericitos , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Enfermedad de Alzheimer/etiología , Humanos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Pericitos/patología , Pericitos/metabolismo , Transducción de Señal , Oligodendroglía/metabolismo , Oligodendroglía/patología , Matriz Extracelular/metabolismo , Microvasos/patología , Microvasos/metabolismo , Análisis de la Célula Individual , Femenino , Masculino , Fosfatidilinositol 3-Quinasas/metabolismoRESUMEN
BACKGROUND: The choroid plexus (ChP) helps maintain the homeostasis of the brain by forming the blood-CSF barrier via tight junctions (TJ) at the choroid plexus epithelial cells, and subsequently preventing neuroinflammation by restricting immune cells infiltration into the central nervous system. However, whether chronic cerebral hypoperfusion causes ChP structural damage and blood-CSF barrier impairment remains understudied. METHODS: The bilateral carotid stenosis (BCAS) model in adult male C57BL/6 J mice was used to induce cerebral hypoperfusion, a model for vascular contributions to cognitive impairment and dementia (VCID). BCAS-mediated changes of the blood-CSF barrier TJ proteins, apical secretory Na+-K+-Cl- cotransporter isoform 1 (NKCC1) protein and regulatory serine-threonine kinases SPAK, and brain infiltration of myeloid-derived immune cells were assessed. RESULTS: BCAS triggered dynamic changes of TJ proteins (claudin 1, claudin 5) accompanied with stimulation of SPAK-NKCC1 complex and NF-κB in the ChP epithelial cells. These changes impacted the integrity of the blood-CSF barrier, as evidenced by ChP infiltration of macrophages/microglia, neutrophils and T cells. Importantly, pharmacological blockade of SPAK with its potent inhibitor ZT1a in BCAS mice attenuated brain immune cell infiltration and improved cognitive neurological function. CONCLUSIONS: BCAS causes chronic ChP blood-CSF damage and immune cell infiltration. Our study sheds light on the SPAK-NKCC1 complex as a therapeutic target in neuroinflammation.
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Estenosis Carotídea , Ratones Endogámicos C57BL , Enfermedades Neuroinflamatorias , Animales , Ratones , Masculino , Enfermedades Neuroinflamatorias/patología , Enfermedades Neuroinflamatorias/metabolismo , Enfermedades Neuroinflamatorias/etiología , Estenosis Carotídea/patología , Barrera Hematoencefálica/patología , Barrera Hematoencefálica/metabolismo , Plexo Coroideo/patología , Plexo Coroideo/metabolismoRESUMEN
The blood-brain barrier (BBB) and blood-retinal barrier (BRB) constitute critical physiochemical interfaces, precisely orchestrating the bidirectional communication between the brain/retina and blood. Increased permeability or leakage of these barriers has been demonstrably linked to age-related vascular and parenchymal damage. While it has been suggested that the gradual aging process may coincide with disruptions in these barriers, this phenomenon is significantly exacerbated in individuals with age-related neurodegenerative disorders (ARND). This review focuses on the microvascular endothelium, a key constituent of BBB and BRB, highlighting the impact of endothelial senescence on barrier dysfunction and exploring recent discoveries regarding core pathways implicated in its breakdown. Subsequently, we address the "vascular senescence hypothesis" for ARND, with a particular emphasis on Alzheimer's disease and age-related macular degeneration, centered on endothelial senescence. Finally, we discuss potential senotherapeutic strategies targeting barrier dysfunction.
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Envejecimiento , Barrera Hematoencefálica , Barrera Hematorretinal , Endotelio Vascular , Humanos , Barrera Hematoencefálica/fisiopatología , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Barrera Hematorretinal/fisiología , Barrera Hematorretinal/metabolismo , Envejecimiento/fisiología , Envejecimiento/patología , Animales , Endotelio Vascular/fisiopatología , Endotelio Vascular/metabolismo , Senescencia Celular/fisiología , Enfermedades Neurodegenerativas/fisiopatología , Enfermedades Neurodegenerativas/metabolismo , Enfermedades Neurodegenerativas/patologíaRESUMEN
Cerebral small vessel disease (CSVD) is a group of pathologies that affect the cerebral blood vessels. CSVD accounts for 25% of strokes and contributes to 45% of dementia. However, the pathogenesis of CSVD remains unclear, involving a variety of complex mechanisms. CSVD may result from dysfunction in the glymphatic system (GS). The GS contains aquaporin-4 (AQP-4), which is in the perivascular space, at the endfeet of the astrocyte. The GS contributes to the removal of waste products from the central nervous system, occupying perivascular spaces and regulating the exchange and movement of cerebrospinal fluid and interstitial fluid. The GS involves astrocytes and aquaporin channels, which are components of the blood-brain barrier, and problems with them may constitute the pathogenesis of CSVD. Vascular risk factors, including diabetes, dilate the perivascular space, disrupting the glymphatic system and the active regulation of AQP-4. CSVD exacerbation due to disorders of the GS is associated with multiple vasculopathies. Dysfunction of the glymphatic system and AQP-4 interferes with the functioning of the blood-brain barrier, which exacerbates CSVD. In a long-term follow-up of CSVD patients with microbleeds, lacunar infarcts, and white matter hyperintensity, several vascular risk factors, including hypertension, increased the risk of ischemic stroke. Dysfunction of the GS may be the cause of CSVD; however, the underlying treatment needs to be studied further.
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Acuaporina 4 , Barrera Hematoencefálica , Enfermedades de los Pequeños Vasos Cerebrales , Sistema Glinfático , Enfermedades de los Pequeños Vasos Cerebrales/metabolismo , Enfermedades de los Pequeños Vasos Cerebrales/patología , Enfermedades de los Pequeños Vasos Cerebrales/etiología , Humanos , Sistema Glinfático/metabolismo , Sistema Glinfático/patología , Acuaporina 4/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Animales , Astrocitos/metabolismo , Astrocitos/patología , Factores de RiesgoRESUMEN
BACKGROUND: In addition to primary injury, secondary injuries related to BBB disruption and immune-inflammatory response also play an important role in intracerebral hemorrhage (ICH). And the Golgi apparatus play an important role in the state of ICH. METHODS: ICH model and GM130-silencing ICH model were established in SD rats. The Garcia score was used to score the neurological defects of the rats. Blood-brain barrier (BBB) integrity were assessed by amount of extravasated Evans blue, and tight junction proteins. The expression of PD-L1 and GM130were detected through Western-blot and the subtype of microglia was showing with Immunofluorescence staining. RESULTS: Compared with the ICH group, GM130-silencing ICH rats got a worsened neurological deficit and enlarged volume of the hematoma. Evan's blue extravasation aggravated as well. The expression of GM130 in peri-hematoma tissue was further decreased, and the morphology and structure of the Golgi apparatus were further damaged. Meanwhile, the GM130 deficit resulted in decreased expression of PD-L1 and more polarization of microglia to the M1 subtype. CONCLUSION: We demonstrate that GM130 could influence the integrity of BBB and plays a role in neuroinflammation via regulation of PD-L1 after ICH. The manipulation of GM130 might be a promising therapeutical target in ICH.
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Antígeno B7-H1 , Barrera Hematoencefálica , Hemorragia Cerebral , Proteínas de la Membrana , Microglía , Animales , Masculino , Ratas , Autoantígenos , Antígeno B7-H1/metabolismo , Antígeno B7-H1/genética , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/genética , Hemorragia Cerebral/patología , Modelos Animales de Enfermedad , Regulación hacia Abajo , Aparato de Golgi/metabolismo , Proteínas de la Membrana/metabolismo , Proteínas de la Membrana/genética , Microglía/metabolismo , Microglía/patología , Ratas Sprague-DawleyRESUMEN
Multiple sclerosis (MS) is a chronic inflammatory neurodegenerative disease leading to progressive demyelination and neuronal loss, with extensive neurological symptoms. As one of the most widespread neurodegenerative disorders, with an age onset of about 30 years, it turns out to be a socio-health and economic issue, thus necessitating therapeutic interventions currently unavailable. Loss of integrity in the blood-brain barrier (BBB) is one of the distinct MS hallmarks. Brain homeostasis is ensured by an endothelial cell-based monolayer at the interface between the central nervous system (CNS) and systemic bloodstream, acting as a selective barrier. MS results in enhanced barrier permeability, mainly due to the breakdown of tight (TJs) and adherens junctions (AJs) between endothelial cells. Specifically, proinflammatory mediator release causes failure in cytoplasmic exposure of junctions, resulting in compromised BBB integrity that enables blood cells to cross the barrier, establishing iron deposition and neuronal impairment. Cells with a compromised cytoskeletal protein network, fiber reorganization, and discontinuous junction structure can occur, resulting in BBB dysfunction. Recent investigations on spatial transcriptomics have proven circularRNAs (circRNAs) to be powerful multi-functional molecules able to epigenetically regulate transcription and structurally support proteins. In the present review, we provide an overview of the recent role ascribed to circRNAs in maintaining BBB integrity/permeability via cytoskeletal stability. Increased knowledge of the mechanisms responsible for impairment and circRNA's role in driving BBB damage and dysfunction might be helpful for the recognition of novel therapeutic targets to overcome BBB damage and unrestrained neurodegeneration.
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Barrera Hematoencefálica , Epigénesis Genética , Esclerosis Múltiple , ARN Circular , Humanos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Esclerosis Múltiple/patología , Esclerosis Múltiple/genética , Esclerosis Múltiple/metabolismo , ARN Circular/genética , ARN Circular/metabolismo , AnimalesRESUMEN
Traumatic brain injury impairs brain function through various mechanisms. Recent studies have shown that alterations in pericytes in various diseases affect neurovascular function, but the effects of TBI on hippocampal pericytes remain unclear. Here, we investigated the effects of RAGE activation on pericytes after TBI using male C57BL/6 J mice. Hippocampal samples were collected at different time points within 7 days after TBI, the expression of PDGFR-ß, NG2 and the HMGB1-S100B/RAGE signaling pathway was assessed by Western blotting, and the integrity of the hippocampal BBB at different time points was measured by immunofluorescence. RAGE-associated BBB damage in hippocampal pericytes occurred early after cortical impact. By culturing primary mouse brain microvascular pericytes, we determined the different effects of HMGB1-S100B on pericyte RAGE. To investigate whether RAGE blockade could protect neurological function after TBI, we reproduced the process of CCI by administering FPS-ZM1 to RAGE-/- mice. TEM images and BBB damage-related assays showed that inhibition of RAGE resulted in a significant improvement in the number of hippocampal vascular basement membranes and tight junctions and a reduction in perivascular oedema compared with those in the untreated group. In contrast, mouse behavioural testing and doublecortin staining indicated that targeting the HMGB1-S100B/RAGE axis after CCI could protect neurological function by reducing pericyte-associated BBB damage. In conclusion, the present study provides experimental evidence for the strong correlation between the pericyte HMGB1-S100B/RAGE axis and NVU damage in the hippocampus at the early stage of TBI and further demonstrates that pericyte RAGE serves as an important target for the protection of neurological function after TBI.
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Barrera Hematoencefálica , Lesiones Traumáticas del Encéfalo , Hipocampo , Ratones Endogámicos C57BL , Pericitos , Receptor para Productos Finales de Glicación Avanzada , Animales , Pericitos/metabolismo , Pericitos/patología , Lesiones Traumáticas del Encéfalo/patología , Lesiones Traumáticas del Encéfalo/metabolismo , Ratones , Masculino , Receptor para Productos Finales de Glicación Avanzada/metabolismo , Hipocampo/metabolismo , Hipocampo/patología , Barrera Hematoencefálica/patología , Barrera Hematoencefálica/metabolismo , Ratones Noqueados , Proteína HMGB1/metabolismo , Subunidad beta de la Proteína de Unión al Calcio S100/metabolismo , BenzamidasRESUMEN
A1 polarization of astrocytes mediated prolonged inflammation contributing to brain injury in ischemic stroke. We have previously shown that AD16 protects against neonatal hypoxic-ischemic brain damage in vivo and oxygen-glucose deprivation in vitro. More recently, AD16 has demonstrated safety, tolerability, and favorable pharmacokinetics in a randomized controlled phase I trial. In this study, we utilized a rat model of transient middle cerebral artery occlusion (tMCAO) to explore whether the anti-inflammatory compound AD16 protects against ischemic brain injury by regulating A1 polarization and its underlying mechanisms. Our results showed that AD16 treatment significantly reduced the brain infarcted volume and improved neurological function in tMCAO rats. GO analysis results show that differential genes among the Sham, tMCAO and AD16 treatment groups are involved in the regulation of cytokine and inflammatory response. KEGG enrichment pathways analysis mainly enriched in cytokine-cytokine receptor interaction, viral protein interaction with cytokine-cytokine receptor, TNF, chemokine, NF-κB and IL-17 signaling pathway. Furthermore, AD16 treatment decreased the permeability of the blood-brain barrier and suppressed neuroinflammation. AD16 treatment also significantly reduced the polarization of A1 and inhibited NF-κB and JAK2/STAT3 signaling pathways. This study demonstrates that AD16 protects against brain injury in ischemic stroke by reducing A1 polarization to suppress neuroinflammation through downregulating NF-κB and JAK2/STAT3 signaling. Our findings uncover a potential molecular mechanism for AD16 and suggest that AD16 holds promising therapeutic potential against cerebral ischemia.
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Astrocitos , Enfermedades Neuroinflamatorias , Animales , Masculino , Ratas , Antiinflamatorios/farmacología , Astrocitos/metabolismo , Astrocitos/efectos de los fármacos , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Isquemia Encefálica/tratamiento farmacológico , Isquemia Encefálica/metabolismo , Isquemia Encefálica/patología , Polaridad Celular/efectos de los fármacos , Citocinas/metabolismo , Modelos Animales de Enfermedad , Regulación hacia Abajo/efectos de los fármacos , Infarto de la Arteria Cerebral Media/tratamiento farmacológico , Infarto de la Arteria Cerebral Media/patología , Infarto de la Arteria Cerebral Media/metabolismo , Enfermedades Neuroinflamatorias/tratamiento farmacológico , Enfermedades Neuroinflamatorias/metabolismo , Fármacos Neuroprotectores/farmacología , Ratas Sprague-Dawley , Transducción de Señal/efectos de los fármacosRESUMEN
Vascular dementia (VaD) is a complex neurodegenerative condition, with cerebral small vessel dysfunctions as the central role in its pathogenesis. Given the lack of suitable animal models to study the disease pathogenesis, we developed a mouse model to closely emulate the clinical scenarios of recurrent transient ischemic attacks (TIAs) leading to VaD using vasoconstricting peptide Endothelin-1(ET-1). We observed that administration of ET-1 led to blood-brain barrier (BBB) disruption and detrimental changes in its components, such as endothelial cells and pericytes, along with neuronal loss and synaptic dysfunction, resulting in irreversible memory loss. Further, in our pursuit of understanding potential interventions, we co-administered pleiotrophin (PTN) alongside ET-1 injections. PTN exhibited remarkable efficacy in preserving vital components of the BBB, including endothelial cells and pericytes, thereby restoring BBB integrity, preventing neuronal loss, and enhancing memory function. Our findings give a valuable framework for understanding the detrimental effects of multiple TIAs on brain health and provide a useful animal model to explore VaD's underlying mechanisms further and pave the way for promising therapies.
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Proteínas Portadoras , Citocinas , Endotelina-1 , Ratones Endogámicos C57BL , Animales , Ratones , Proteínas Portadoras/metabolismo , Endotelina-1/toxicidad , Citocinas/metabolismo , Masculino , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/patología , Disfunción Cognitiva/etiología , Disfunción Cognitiva/tratamiento farmacológico , Disfunción Cognitiva/patología , Modelos Animales de Enfermedad , Demencia Vascular/patología , Demencia Vascular/tratamiento farmacológicoRESUMEN
Subarachnoid hemorrhage (SAH) significantly compromises the blood-brain barrier (BBB) and impairs patient recovery. This study elucidates the critical role of astrocytic Neogenin-1 (NEO1) in BBB integrity post-SAH and examines the regulatory effects of hepcidin on endothelial cell (EC) function amid NEO1-mediated disruptions in iron homeostasis. Proteomic analyses of cerebrospinal fluid (CSF) from SAH patients revealed a substantial decrease in NEO1 expression, identifying it as a key factor in BBB integrity. 111 CSF proteins were significantly reduced in early SAH stages (days 1-3), with NEO1 among the most significantly altered. This dysregulation was linked to poorer patient outcomes, as indicated by a negative correlation between NEO1 levels and Modified Rankin Scale scores six months post-SAH (R = -0.4743, P < 0.0001). Experimental models further highlighted the importance of NEO1: SAH model and NEO1GFAP-Cre mice exhibited exacerbated EC dysfunction and increased BBB permeability, evidenced by significant Evans Blue retention and dextran leakage in the parietal cortex, effects that were mitigated by hepcidin administration. Our findings highlight the complex interplay between astrocytic signaling and endothelial function in SAH pathophysiology. The loss of astrocytic NEO1 led to increased EC proliferation and altered BBB structure, as confirmed by transmission electron microscopy and immunostaining for PECAM-1, indicating heightened blood vessel density in the affected cortex. Hepcidin treatment effectively reversed the EC dysfunction and BBB disruption in both NEO1-cKO mice and the SAH model, highlighting its potential as a therapeutic agent to enhance recovery and improve prognosis following SAH.
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Astrocitos , Barrera Hematoencefálica , Hepcidinas , Hemorragia Subaracnoidea , Hemorragia Subaracnoidea/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Barrera Hematoencefálica/efectos de los fármacos , Animales , Hepcidinas/metabolismo , Hepcidinas/genética , Astrocitos/metabolismo , Humanos , Ratones , Masculino , Ratones Endogámicos C57BL , Células Endoteliales/metabolismo , Modelos Animales de Enfermedad , Femenino , Persona de Mediana Edad , Proteínas de la Membrana/metabolismoRESUMEN
Brain metastases account for more than 50 % of intracranial central nervous system tumors. The blood-brain barrier (BBB) is mainly composed of endothelial cells, which exhibit low endocytosis and high efflux pumps. Although they are connected by continuous tight junctions and serve as a protective insulation, the BBB does not prevent the development of brain metastases from non-small cell lung cancer (NSCLC). Improving understanding on the mechanisms underlying the development of brain metastasis and the differential molecular characteristics relative to the primary tumor are therefore key in the treatment of brain metastases. This study evaluated the differential expression of miR-522-3p in NSCLC and brain metastases using the Gene Expression Omnibus database. NSCLC brain metastasis model was constructed to screen for cell lines that demonstrated high potential for brain metastasis; We also observed differential expression of miRNA-522-3p in the paraffin-embedded specimens of non-small cell lung cancer and brain metastases from our hospital. The molecular biological functions of miRNA-522-3p were verified using 5-ethynyl-2'-deoxyuridine (EdU) proliferation assay and Transwell invasion assays. RNA-seq was employed to identify downstream target proteins, and the dual-luciferase reporter assay confirmed Tensin 1 (TNS1), a protein that links the actin cytoskeleton to the extracellular matrix, as the downstream regulatory target protein. In vitro blood-brain barrier models and co-culture models were constructed to further identify the role of miRNA-522-3p and TNS1; the expression of BBB-related proteins (ZO-1 and OLCN) was also identified. In vivo experiments were performed to verify the effects of miRNA-522-3p on the time and incidence of NSCLC brain metastasis. The results showed significantly high expression in GSE51666; consistent results were obtained in brain metastasis cells and paraffin samples. RNA-seq combined with miRNA target protein prediction demonstrated TNS1 to be directly downstream of miR-522-3p and to be associated with cell proliferation and invasion. By regulating ZO-1 and OCLN expression, mi-522-3p/TNS1 may increase tumor cell penetration through the BBB while decreasing its permeability. In vivo, miR-522-3p was further demonstrated to significantly promote the formation of brain metastases. miR-522-3p/TNS1 can affect BBB permeability and encourage the growth of brain metastases by modifying the BBB TJ proteins. This axis offers new therapeutic targets for the prevention of brain metastasis.
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Barrera Hematoencefálica , Neoplasias Encefálicas , Carcinoma de Pulmón de Células no Pequeñas , Regulación Neoplásica de la Expresión Génica , Neoplasias Pulmonares , MicroARNs , Tensinas , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , MicroARNs/genética , MicroARNs/metabolismo , Carcinoma de Pulmón de Células no Pequeñas/patología , Carcinoma de Pulmón de Células no Pequeñas/genética , Carcinoma de Pulmón de Células no Pequeñas/metabolismo , Humanos , Neoplasias Pulmonares/patología , Neoplasias Pulmonares/genética , Neoplasias Pulmonares/secundario , Neoplasias Pulmonares/metabolismo , Neoplasias Encefálicas/secundario , Neoplasias Encefálicas/genética , Neoplasias Encefálicas/patología , Neoplasias Encefálicas/metabolismo , Animales , Regulación Neoplásica de la Expresión Génica/genética , Ratones , Tensinas/metabolismo , Tensinas/genética , Proliferación Celular/genética , Ratones Desnudos , Línea Celular Tumoral , Permeabilidad , Ratones Endogámicos BALB C , Movimiento Celular/genéticaRESUMEN
BACKGROUND: Cerebral ischemia is characterized by its rapid onset and high rates of recurrence, morbidity, and mortality, with blood-brain barrier (BBB) permeability playing a vital role in brain injury. Therefore, it is important to understand the molecular mechanism which regulates the BBB during cerebral ischemia. MATERIALS AND METHODS: An in vitro model of oxygen-glucose deprivation (OGD) and an in vivo model of cerebral ischemia/reperfusion (I/R) were constructed. PD-1 overexpression vectors and vectors containing si-RNA were transfected and injected into in vitro and in vivo models. Western blotting, real-time quantitative PCR (qPCR), immunofluorescence (IF) analysis, and immunohistochemical staining were employed to evaluate the expression levels of programmed cell death-1 (PD-1), microglia M1 and M2 biomarkers, and tight junction proteins. Flow cytometry and ELISA were used to measure the levels of pro-inflammatory cytokines. The BBB permeability of brain tissues was evaluated by Evans blue dye (EBD) extravasation and transendothelial electrical resistance (TEER). Brain water content was measured to assess the extent of inflammatory exudation. The infarct volume and neurological severity score (NSS) were used to assess the severity of brain injury. Brain cell apoptosis was assessed by the TUNEL assay and hematoxylin-eosin (H&E) staining. RESULTS: PD-1 helped to convert the microglia M1 phenotype to the M2 phenotype and to reduce BBB permeability both in vitro and in vivo. Overexpression of PD-1 promoted a shift of the M1 phenotype to the M2 phenotype and reduced BBB permeability via the ERK and p38 MAPK signaling pathways. PD-1 reduced inflammatory exudation, BBB permeability, cell apoptosis, and brain injury in vivo. CONCLUSION: Our present study verified that PD-1 exerts an anti-inflammatory effect by converting the microglia M1 phenotype to the M2 phenotype, reducing BBB permeability, and thereby relieves brain injury caused by cerebral ischemia. PD-1 is potential therapeutic target for brain injury caused by cerebral ischemia.
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Barrera Hematoencefálica , Isquemia Encefálica , Sistema de Señalización de MAP Quinasas , Microglía , Receptor de Muerte Celular Programada 1 , Daño por Reperfusión , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Animales , Microglía/metabolismo , Daño por Reperfusión/metabolismo , Receptor de Muerte Celular Programada 1/metabolismo , Isquemia Encefálica/metabolismo , Masculino , Ratones , Sistema de Señalización de MAP Quinasas/fisiología , Apoptosis/fisiología , Ratones Endogámicos C57BL , Polaridad Celular/fisiologíaRESUMEN
Oxidative stress is a prominent causal factor in the premature senescence of microvascular endothelial cells and the ensuing blood-brain barrier (BBB) dysfunction. Through the exposure of an in vitro model of human BBB, composed of brain microvascular endothelial cells (BMECs), astrocytes, and pericytes to H2O2, this study examined whether a specific targeting of the p38MAPK/NF-κB pathway and/or senescent cells could delay oxidative stress-mediated EC senescence and protect the BBB. Enlarged BMECs, displaying higher ß-galactosidase activity, γH2AX staining, p16 expression, and impaired tubulogenic capacity, were regarded as senescent. The BBB established with senescent BMECs had reduced transendothelial electrical resistance and increased paracellular flux, which are markers of BBB integrity and function, respectively. Premature senescence disrupted plasma-membrane localization of the tight junction protein, zonula occludens-1, and elevated basement membrane-degrading matrix metalloproteinase-2 activity and pro-inflammatory cytokine release. Inhibition of p38MAPK by BIRB796 and NF-κB by QNZ and the elimination of senescent cells by a combination of dasatinib and quercetin attenuated the effects of H2O2 on senescence markers; suppressed release of the pro-inflammatory cytokines interleukin-8, monocyte chemoattractant protein-1, and intercellular adhesion molecule-1; restored tight junctional unity; and improved BBB function. In conclusion, therapeutic approaches that mitigate p38MAPK/NF-κB activity and senescent cell accumulation in the cerebrovasculature may successfully protect BBB from oxidative stress-induced BBB dysfunction.
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Barrera Hematoencefálica , Senescencia Celular , Células Endoteliales , Peróxido de Hidrógeno , FN-kappa B , Estrés Oxidativo , Senoterapéuticos , Proteínas Quinasas p38 Activadas por Mitógenos , Estrés Oxidativo/efectos de los fármacos , Humanos , Senescencia Celular/efectos de los fármacos , Células Endoteliales/metabolismo , Células Endoteliales/efectos de los fármacos , FN-kappa B/metabolismo , Proteínas Quinasas p38 Activadas por Mitógenos/metabolismo , Barrera Hematoencefálica/efectos de los fármacos , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Senoterapéuticos/farmacología , Peróxido de Hidrógeno/farmacología , Transducción de Señal/efectos de los fármacos , Proteína de la Zonula Occludens-1/metabolismoRESUMEN
Parkinson's disease (PD) is the second most common neurodegenerative disease, and its hallmark pathological features are the loss of dopaminergic (DA) neurons in the midbrain substantia nigra pars compacta (SNpc) and the accumulation of alpha-synuclein (α-syn). It has been shown that the integrity of the blood-brain barrier (BBB) is damaged in PD patients, and a large number of infiltrating T cells and inflammatory cytokines have been detected in the cerebrospinal fluid (CSF) and brain parenchyma of PD patients and PD animal models, including significant change in the number and proportion of different CD4+ T cell subsets. This suggests that the neuroinflammatory response caused by CD4+ T cells is an important risk factor for the development of PD. Here, we systematically review the differentiation of CD4+ T cell subsets, and focus on describing the functions and mechanisms of different CD4+ T cell subsets and their secreted cytokines in PD. We also summarize the current immunotherapy targeting CD4+ T cells with a view to providing assistance in the diagnosis and treatment of PD.
Asunto(s)
Linfocitos T CD4-Positivos , Diferenciación Celular , Citocinas , Enfermedad de Parkinson , Enfermedad de Parkinson/patología , Enfermedad de Parkinson/inmunología , Enfermedad de Parkinson/metabolismo , Humanos , Linfocitos T CD4-Positivos/inmunología , Linfocitos T CD4-Positivos/metabolismo , Animales , Citocinas/metabolismo , Subgrupos de Linfocitos T/inmunología , Subgrupos de Linfocitos T/metabolismo , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Barrera Hematoencefálica/inmunología , alfa-Sinucleína/metabolismo , alfa-Sinucleína/inmunologíaRESUMEN
AIMS: This study aimed to explore the effects of long noncoding RNA (lncRNA) H19 knockdown on angiogenesis and blood-brain barrier (BBB) integrity following cerebral ischemia/reperfusion (I/R) and elucidate their underlying regulatory mechanisms. METHODS: A middle cerebral artery occlusion/reperfusion model was used to induce cerebral I/R injury. The cerebral infarct volume and neurological impairment were assessed using 2,3,5-triphenyl-tetrazolium chloride staining and neurobehavioral tests, respectively. Relevant proteins were evaluated using western blotting and immunofluorescence staining. Additionally, a bioinformatics website was used to predict the potential target genes of lncRNA H19. Finally, a rescue experiment was conducted to confirm the potential mechanism. RESULTS: Silencing of H19 significantly decreased the cerebral infarct volume, enhanced the recovery of neurological function, mitigated BBB damage, and stimulated endothelial cell proliferation following ischemic stroke. Insulin-like growth factor 2 mRNA-binding protein 2 (IMP2) is predicted to be a potential target gene for lncRNA H19. H19 knockdown increased IMP2 protein expression and IMP2 inhibition reversed the protective effects of H19 inhibition. CONCLUSION: Downregulation of H19 enhances angiogenesis and mitigates BBB damage by regulating IMP2, thereby alleviating cerebral I/R injury.
Asunto(s)
Angiogénesis , Infarto de la Arteria Cerebral Media , Accidente Cerebrovascular Isquémico , ARN Largo no Codificante , Proteínas de Unión al ARN , Animales , Ratones , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Técnicas de Silenciamiento del Gen/métodos , Infarto de la Arteria Cerebral Media/metabolismo , Infarto de la Arteria Cerebral Media/patología , Accidente Cerebrovascular Isquémico/metabolismo , Accidente Cerebrovascular Isquémico/genética , Accidente Cerebrovascular Isquémico/patología , Ratones Endogámicos C57BL , Neovascularización Fisiológica/fisiología , Daño por Reperfusión/metabolismo , Daño por Reperfusión/genética , Daño por Reperfusión/patología , ARN Largo no Codificante/genética , ARN Largo no Codificante/metabolismo , Proteínas de Unión al ARN/metabolismo , Proteínas de Unión al ARN/genética , Modelos Animales de EnfermedadRESUMEN
The meninges, choroid plexus (CP) and blood-brain barrier (BBB) are recognized as important gateways for peripheral immune cell trafficking into the central nervous system (CNS). Accumulation of peripheral immune cells in brain parenchyma can be observed during aging and Alzheimer's disease (AD). However, the mechanisms by which peripheral immune cells enter the CNS through these three pathways and how they interact with resident cells within the CNS to cause brain injury are not fully understood. In this paper, we review recent research on T cells recruitment in the brain during aging and AD. This review focuses on the possible pathways through which T cells infiltrate the brain, the evidence that T cells are recruited to the brain, and how infiltrating T cells interact with the resident cells in the CNS during aging and AD. Unraveling these issues will contribute to a better understanding of the mechanisms of aging and AD from the perspective of immunity, and hopefully develop new therapeutic strategies for brain aging and AD.
Asunto(s)
Envejecimiento , Enfermedad de Alzheimer , Barrera Hematoencefálica , Encéfalo , Linfocitos T , Humanos , Enfermedad de Alzheimer/inmunología , Enfermedad de Alzheimer/patología , Enfermedad de Alzheimer/metabolismo , Envejecimiento/inmunología , Envejecimiento/patología , Envejecimiento/metabolismo , Encéfalo/inmunología , Encéfalo/patología , Encéfalo/metabolismo , Animales , Linfocitos T/inmunología , Barrera Hematoencefálica/inmunología , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Movimiento Celular/inmunología , Movimiento Celular/fisiologíaRESUMEN
Multiphoton intravital microscopy (MP-IVM) is an imaging technique used for the observation of living organisms at a microscopic resolution. The tissue of interest is exposed through a window allowing imaging of cells in real time. Using MP-IVM, the temporospatial kinetics of leukocyte transendothelial migration can be visualized and quantitated using reporter mice and cell-specific fluorophore-conjugated monoclonal antibodies to track the leukocytes within and outside of vascular beds. Here we describe a method used to study neutrophil transendothelial migration and blood-brain barrier permeability in a mouse model of herpes simplex virus I (HSV) encephalitis.
Asunto(s)
Barrera Hematoencefálica , Modelos Animales de Enfermedad , Encefalitis por Herpes Simple , Microscopía Intravital , Microscopía de Fluorescencia por Excitación Multifotónica , Neutrófilos , Migración Transendotelial y Transepitelial , Animales , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/virología , Barrera Hematoencefálica/patología , Ratones , Microscopía Intravital/métodos , Microscopía de Fluorescencia por Excitación Multifotónica/métodos , Neutrófilos/metabolismo , Encefalitis por Herpes Simple/patología , Encefalitis por Herpes Simple/virología , Encefalitis por Herpes Simple/metabolismo , Herpesvirus Humano 1/fisiología , PermeabilidadRESUMEN
Although most laminin isoforms are neuroprotective in stroke, mural cell-derived laminin-α5 plays a detrimental role in an ischemia-reperfusion model. To determine whether this deleterious effect is an intrinsic feature of mural cell-derived laminin-α5 or unique to ischemic stroke, we performed loss-of-function studies using middle-aged mice with laminin-α5 deficiency in mural cells (α5-PKO) in an intracerebral hemorrhage (ICH) model. Control and α5-PKO mice exhibited comparable changes in all parameters examined, including hematoma size, neuronal death, neurological function, blood-brain barrier integrity, and reactive gliosis. These findings highlight a minimal role of mural cell-derived laminin-α5 in ICH. Together with the detrimental role of mural cell-derived laminin-α5 in ischemic stroke, these negative results in ICH model suggest that mural cell-derived laminin-α5 may exert distinct functions in different diseases.
Asunto(s)
Barrera Hematoencefálica , Hemorragia Cerebral , Laminina , Animales , Laminina/metabolismo , Hemorragia Cerebral/metabolismo , Hemorragia Cerebral/patología , Ratones , Barrera Hematoencefálica/metabolismo , Barrera Hematoencefálica/patología , Ratones Noqueados , Masculino , Modelos Animales de Enfermedad , Ratones Endogámicos C57BLRESUMEN
Type 2 Diabetes Mellitus (T2DM) is linked to multiple complications, including cognitive impairment, and the prevalence of memory-related neurodegenerative diseases is higher in T2DM patients. One possible theory is the alteration of the microvascular and macrovascular environment of the blood-brain barrier (BBB). In this study, we employed different approaches, including RT-PCR, functional pharmacokinetic studies using sodium fluorescein (NaFL), and confocal microscopy, to characterize the functional and molecular integrity of the BBB in a T2DM animal model, leptin receptor-deficient mutant mice (Leprdb/db mice). As a result, VCAM-1, ICAM-1, MMP-9, and S100b (BBB-related markers) dysregulation was observed in the Leprdb/db animal model compared to littermate wild-type mice. The brain concentration of sodium fluorescein (NaFL) increased significantly in Leprdb/db untreated mice compared to insulin-treated mice. Therefore, the permeability of NaFL was higher in Leprdb/db control mice than in all remaining groups. Identifying the factors that increase the BBB in Leprdb/db mice will provide a better understanding of the BBB microvasculature and present previously undescribed findings of T2DM-related brain illnesses, filling knowledge gaps in this emerging field of research.