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1.
Signal Transduct Target Ther ; 6(1): 337, 2021 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-34489403

RESUMO

SARS-CoV-2 has been reported to show a capacity for invading the brains of humans and model animals. However, it remains unclear whether and how SARS-CoV-2 crosses the blood-brain barrier (BBB). Herein, SARS-CoV-2 RNA was occasionally detected in the vascular wall and perivascular space, as well as in brain microvascular endothelial cells (BMECs) in the infected K18-hACE2 transgenic mice. Moreover, the permeability of the infected vessel was increased. Furthermore, disintegrity of BBB was discovered in the infected hamsters by administration of Evans blue. Interestingly, the expression of claudin5, ZO-1, occludin and the ultrastructure of tight junctions (TJs) showed unchanged, whereas, the basement membrane was disrupted in the infected animals. Using an in vitro BBB model that comprises primary BMECs with astrocytes, SARS-CoV-2 was found to infect and cross through the BMECs. Consistent with in vivo experiments, the expression of MMP9 was increased and collagen IV was decreased while the markers for TJs were not altered in the SARS-CoV-2-infected BMECs. Besides, inflammatory responses including vasculitis, glial activation, and upregulated inflammatory factors occurred after SARS-CoV-2 infection. Overall, our results provide evidence supporting that SARS-CoV-2 can cross the BBB in a transcellular pathway accompanied with basement membrane disrupted without obvious alteration of TJs.


Assuntos
Membrana Basal/metabolismo , Barreira Hematoencefálica/metabolismo , COVID-19/metabolismo , SARS-CoV-2/metabolismo , Junções Íntimas/metabolismo , Enzima de Conversão de Angiotensina 2/genética , Enzima de Conversão de Angiotensina 2/metabolismo , Animais , Membrana Basal/patologia , Membrana Basal/virologia , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/virologia , COVID-19/genética , COVID-19/patologia , Chlorocebus aethiops , Modelos Animais de Doenças , Humanos , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , SARS-CoV-2/genética , Junções Íntimas/genética , Junções Íntimas/patologia , Junções Íntimas/virologia , Células Vero
2.
Int J Mol Sci ; 22(16)2021 Aug 04.
Artigo em Inglês | MEDLINE | ID: mdl-34445097

RESUMO

The disruption of blood-brain barrier (BBB) for multiple sclerosis (MS) pathogenesis has a double effect: early on during the onset of the immune attack and later for the CNS self-sustained 'inside-out' demyelination and neurodegeneration processes. This review presents the characteristics of BBB malfunction in MS but mostly highlights current developments regarding the impairment of the neurovascular unit (NVU) and the metabolic and mitochondrial dysfunctions of the BBB's endothelial cells. The hypoxic hypothesis is largely studied and agreed upon recently in the pathologic processes in MS. Hypoxia in MS might be produced per se by the NVU malfunction or secondary to mitochondria dysfunction. We present three different but related terms that denominate the ongoing neurodegenerative process in progressive forms of MS that are indirectly related to BBB disruption: progression independent of relapses, no evidence of disease activity and smoldering demyelination or silent progression. Dimethyl fumarate (DMF), modulators of S1P receptor, cladribine and laquinimode are DMTs that are able to cross the BBB and exhibit beneficial direct effects in the CNS with very different mechanisms of action, providing hope that a combined therapy might be effective in treating MS. Detailed mechanisms of action of these DMTs are described and also illustrated in dedicated images. With increasing knowledge about the involvement of BBB in MS pathology, BBB might become a therapeutic target in MS not only to make it impenetrable against activated immune cells but also to allow molecules that have a neuroprotective effect in reaching the cell target inside the CNS.


Assuntos
Barreira Hematoencefálica/patologia , Esclerose Múltipla/patologia , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Progressão da Doença , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/patologia , Esclerose Múltipla/tratamento farmacológico , Esclerose Múltipla/metabolismo
3.
Nat Biomed Eng ; 5(8): 847-863, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-34385693

RESUMO

The therapeutic efficacy of stem cells transplanted into an ischaemic brain depends primarily on the responses of the neurovascular unit. Here, we report the development and applicability of a functional neurovascular unit on a microfluidic chip as a microphysiological model of ischaemic stroke that recapitulates the function of the blood-brain barrier as well as interactions between therapeutic stem cells and host cells (human brain microvascular endothelial cells, pericytes, astrocytes, microglia and neurons). We used the model to track the infiltration of a number of candidate stem cells and to characterize the expression levels of genes associated with post-stroke pathologies. We observed that each type of stem cell showed unique neurorestorative effects, primarily by supporting endogenous recovery rather than through direct cell replacement, and that the recovery of synaptic activities is correlated with the recovery of the structural and functional integrity of the neurovascular unit rather than with the regeneration of neurons.


Assuntos
AVC Isquêmico/terapia , Dispositivos Lab-On-A-Chip , Transplante de Células-Tronco , Astrócitos/citologia , Astrócitos/metabolismo , Barreira Hematoencefálica/química , Barreira Hematoencefálica/metabolismo , Técnicas de Cocultura , Células Endoteliais/citologia , Células Endoteliais/metabolismo , Humanos , Microglia/citologia , Microglia/metabolismo , Microvasos/citologia , Modelos Biológicos , Neurônios/citologia , Neurônios/metabolismo , Pericitos/citologia , Pericitos/metabolismo , Células-Tronco/citologia , Células-Tronco/metabolismo
4.
J Enzyme Inhib Med Chem ; 36(1): 1860-1873, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34425715

RESUMO

To discover novel scaffolds as leads against dementia, a series of δ-aryl-1,3-dienesulfonyl fluorides with α-halo, α-aryl and α-alkynyl were assayed for ChE inhibitory activity, in which compound A10 was identified as a selective BuChE inhibitor (IC50 = 0.021 µM for eqBChE, 3.62 µM for hBuChE). SAR of BuChE inhibition showed: (i) o- > m- > p-; -OCH3 > -CH3 > -Cl (-Br) for δ-aryl; (ii) α-Br > α-Cl, α-I. Compound A10 exhibited neuroprotective, BBB penetration, mixed competitive inhibitory effect on BuChE (Ki = 29 nM), and benign neural and hepatic safety. Treatment with A10 could almost entirely recover the Aß1-42-induced cognitive dysfunction to the normal level, and the assessment of total amount of Aß1-42 confirmed its anti-amyloidogenic profile. Therefore, the potential BuChE inhibitor A10 is a promising effective lead for the treatment of AD.


Assuntos
Doença de Alzheimer/tratamento farmacológico , Inibidores da Colinesterase/química , Colinesterases/metabolismo , Fármacos Neuroprotetores/química , Ácidos Sulfínicos/química , Alcinos/química , Amiloide/metabolismo , Animais , Comportamento Animal , Barreira Hematoencefálica/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Inibidores da Colinesterase/farmacologia , Desenho de Fármacos , Humanos , Fígado , Masculino , Camundongos Endogâmicos ICR , Simulação de Acoplamento Molecular , Estrutura Molecular , Teste do Labirinto Aquático de Morris , Sistema Nervoso , Fármacos Neuroprotetores/farmacologia , Relação Estrutura-Atividade , Ácidos Sulfínicos/farmacologia
5.
Int J Mol Sci ; 22(16)2021 Aug 19.
Artigo em Inglês | MEDLINE | ID: mdl-34445635

RESUMO

Currently, migraine is treated mainly by targeting calcitonin gene-related peptides, although the efficacy of this method is limited and new treatment strategies are desired. Neuroinflammation has been implicated in the pathogenesis of migraine. In patients with migraine, peripheral levels of pro-inflammatory cytokines, such as interleukin-1ß (IL-1ß) and tumor necrosis factor-α, are known to be increased. Additionally, animal models of headache have demonstrated that immunological responses associated with cytokines are involved in the pathogenesis of migraine. Furthermore, these inflammatory mediators might alter the function of tight junctions in brain vascular endothelial cells in animal models, but not in human patients. Based on clinical findings showing elevated IL-1ß, and experimental findings involving IL-1ß and both the peripheral trigeminal ganglion and central trigeminal vascular pathways, regulation of the Il-1ß/IL-1 receptor type 1 axis might lead to new treatments for migraine. However, the integrity of the blood-brain barrier is not expected to be affected during attacks in patients with migraine.


Assuntos
Barreira Hematoencefálica/patologia , Encéfalo/patologia , Permeabilidade da Membrana Celular , Inflamação/complicações , Transtornos de Enxaqueca/patologia , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/imunologia , Humanos , Transtornos de Enxaqueca/etiologia
6.
Biomaterials ; 276: 121065, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34391018

RESUMO

Clearance of peripheral amyloid-ß (Aß) has been demonstrated particularly promising for overcoming the blood-brain barrier (BBB) hurdle to remove brain-derived Aß associated with Alzheimer's disease (AD). However, currently used therapeutic agents targeting peripheral Aß cannot simultaneously achieve plasma Aß enrichment and enhanced clearance, which may result in poor bioavailability and rather low efficacy. Moreover, most of therapeutic agents usually promote the unfavorable aggregation of Aß. Herein, we construct a near-infrared (NIR) regulated surface-transformable and target peptide-guided upconversion platform (UCNP/ONA-P/K), serving as a safe and effective way for Aß clearance. Taking advantage of extended blood circulation, high selectivity toward Aß, and surface-transformable property, such UCNP/ONA-P/K can address the challenges of peripheral Aß clearance by a combination of enhancing the enrichment of plasma Aß, preventing the unfavorable aggregation of Aß and simultaneously facilitating the hepatic clearance of the captured Aß. After verified by a series of systematic toxicity evaluation, cell uptake, deep tissue penetration, and hemolytic experiments, in vivo studies demonstrate that UCNP/ONA-P/K can efficiently decrease brain Aß burden and reverse memory deficits in 3xTg-AD mice. Overall, this NIR multi-functional design provides a new biocompatible and efficient way for Aß removal, which will promote the application of peripheral clearance of Aß for AD treatment.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/tratamento farmacológico , Peptídeos beta-Amiloides/metabolismo , Animais , Transporte Biológico , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Camundongos
7.
Int J Mol Sci ; 22(16)2021 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-34445318

RESUMO

Recent studies revealed that the activation of serotonergic 5-HT1A and muscarinic M1, M4, or M5 receptors prevent MK-801-induced cognitive impairments in animal models. In the present study, the effectiveness of the simultaneous activation of 5-HT1A and muscarinic receptors at preventing MK-801-induced cognitive deficits in novel object recognition (NOR) or Y-maze tests was investigated. Activators of 5-HT1A (F15599), M1 (VU0357017), M4 (VU0152100), or M5 (VU0238429) receptors administered at top doses for seven days reversed MK-801-induced deficits in the NOR test, similar to the simultaneous administration of subeffective doses of F15599 (0.05 mg/kg) with VU0357017 (0.15 mg/kg), VU0152100 (0.05 mg/kg), or VU0238429 (1 mg/kg). The compounds did not prevent the MK-801-induced impairment when administered acutely. Their activity was less evident in the Y-maze. Pharmacokinetic studies revealed high brain penetration of F15599 (brain/plasma ratio 620%), which was detected in the frontal cortex (FC) up to 2 h after administration. Decreases in the brain penetration properties of the compounds were observed after acute administration of the combinations, which might have influenced behavioral responses. This negative effect on brain penetration was not observed when the compounds were administered repeatedly. Based on our results, prolonged administration of a 5-HT1A activator with muscarinic receptor ligands may be effective at reversing cognitive decline related to schizophrenia, and the FC may play a critical role in this interaction.


Assuntos
Colinérgicos/farmacologia , Disfunção Cognitiva/tratamento farmacológico , Córtex Pré-Frontal/efeitos dos fármacos , Esquizofrenia/tratamento farmacológico , Agonistas do Receptor de Serotonina/farmacologia , Animais , Benzamidas/farmacocinética , Benzamidas/farmacologia , Benzamidas/uso terapêutico , Barreira Hematoencefálica/metabolismo , Colinérgicos/farmacocinética , Colinérgicos/uso terapêutico , Disfunção Cognitiva/etiologia , Maleato de Dizocilpina/toxicidade , Masculino , Aprendizagem em Labirinto , Camundongos , Piperidinas/farmacocinética , Piperidinas/farmacologia , Piperidinas/uso terapêutico , Córtex Pré-Frontal/metabolismo , Piridinas/farmacocinética , Piridinas/farmacologia , Piridinas/uso terapêutico , Pirimidinas/farmacocinética , Pirimidinas/farmacologia , Pirimidinas/uso terapêutico , Receptores Muscarínicos/metabolismo , Receptores de Serotonina/metabolismo , Esquizofrenia/complicações , Agonistas do Receptor de Serotonina/farmacocinética , Agonistas do Receptor de Serotonina/uso terapêutico , Tiofenos/farmacocinética , Tiofenos/farmacologia , Tiofenos/uso terapêutico
8.
Microb Pathog ; 159: 105143, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34400281

RESUMO

Listeria monocytogenes crossing the blood-brain barrier in the form of "Trojan Horse" is of great significance for the establishment of bacterial encephalitis and meningitis. Induction of cell migration and crossing the blood-brain barrier is very important to understand the Listeria pathogenesis. The Rho GTPases family is considered a key factor in regulating cell migration. This study was designed to investigate the expression of Rho GTPases and their effect on the behavior of cell migration and the stimulation of immune factors. Selective Rho GTPases were investigated by real-time PCR and Western blot. Among these, the expression of RhoA was significantly increased following the infection of Listeria monocytogenes in macrophages. Further, we found that RhoA improves the migration of macrophages and expression of IL-1ß, IL-6, and TNF-α. The expression of IL-1ß, IL-6 and TNF-α possibly facilitates the migration and adhesion of macrophages to cross the blood-brain barrier. This study provides preliminary ground to investigate the detailed mechanism of Listeria monocytogenes crossing the blood-brain barrier.


Assuntos
Listeria monocytogenes , Listeriose , Barreira Hematoencefálica/metabolismo , Citocinas/metabolismo , Humanos , Listeria monocytogenes/metabolismo , Macrófagos/metabolismo , Proteínas rho de Ligação ao GTP/genética
9.
Int J Mol Sci ; 22(16)2021 Aug 18.
Artigo em Inglês | MEDLINE | ID: mdl-34445572

RESUMO

Multiple sclerosis (MS) is an autoimmune disease of the Central Nervous System, characterized by an inflammatory process leading to the destruction of myelin with neuronal death and neurodegeneration. In MS, lymphocytes cross the blood-brain barrier, creating inflammatory demyelinated plaques located primarily in the white matter. MS potential treatments involve various mechanisms of action on immune cells, immunosuppression, inhibition of the passage through the blood-brain barrier, and immunotolerance. Bio-nanotechnology represents a promising approach to improve the treatment of autoimmune diseases by its ability to affect the immune responses. The use of nanotechnology has been actively investigated for the development of new MS therapies. In this review, we summarize the results of the studies on natural and artificial vesicles and nanoparticles, and take a look to the future clinical perspectives for their application in the MS therapy.


Assuntos
Barreira Hematoencefálica/metabolismo , Sistemas de Liberação de Medicamentos , Vesículas Extracelulares/química , Imunossupressores/farmacologia , Lipossomos/administração & dosagem , Esclerose Múltipla/tratamento farmacológico , Nanopartículas/administração & dosagem , Animais , Barreira Hematoencefálica/efeitos dos fármacos , Humanos , Imunossupressores/administração & dosagem , Lipossomos/química , Esclerose Múltipla/metabolismo , Esclerose Múltipla/patologia , Nanopartículas/química
10.
ACS Appl Mater Interfaces ; 13(33): 39018-39029, 2021 Aug 25.
Artigo em Inglês | MEDLINE | ID: mdl-34397215

RESUMO

Targeting nanoparticles as drug delivery platforms is crucial to facilitate their cellular entry. Docking of nanoparticles by targeting ligands on cell membranes is the first step for the initiation of cellular uptake. As a model system, we studied brain microvascular endothelial cells, which form the anatomical basis of the blood-brain barrier, and the tripeptide glutathione, one of the most effective targeting ligands of nanoparticles to cross the blood-brain barrier. To investigate this initial docking step between glutathione and the membrane of living brain endothelial cells, we applied our recently developed innovative optical method. We present a microtool, with a task-specific geometry used as a probe, actuated by multifocus optical tweezers to characterize the adhesion probability and strength of glutathione-coated surfaces to the cell membrane of endothelial cells. The binding probability of the glutathione-coated surface and the adhesion force between the microtool and cell membrane was measured in a novel arrangement: cells were cultured on a vertical polymer wall and the mechanical forces were generated laterally and at the same time, perpendicularly to the plasma membrane. The adhesion force values were also determined with more conventional atomic force microscopy (AFM) measurements using functionalized colloidal probes. The optical trapping-based method was found to be suitable to measure very low adhesion forces (≤ 20 pN) without a high level of noise, which is characteristic for AFM measurements in this range. The holographic optical tweezers-directed functionalized microtools may help characterize the adhesion step of nanoparticles initiating transcytosis and select ligands to target nanoparticles.


Assuntos
Membrana Celular/metabolismo , Células Endoteliais/metabolismo , Glutationa/metabolismo , Nanopartículas/metabolismo , Pinças Ópticas , Fenômenos Biofísicos , Barreira Hematoencefálica/metabolismo , Encéfalo , Adesão Celular , Membrana Celular/ultraestrutura , Células Endoteliais/citologia , Galactosamina/química , Humanos , Ligantes , Microscopia de Força Atômica , Nanopartículas/química , Polietilenoglicóis/química , Polímeros/metabolismo , Propriedades de Superfície , Transcitose
11.
Inorg Chem ; 60(16): 12610-12620, 2021 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-34351146

RESUMO

Herein, we report a new series of bifunctional chelators (BFCs) with a high affinity for amyloid aggregates, a strong binding affinity toward Cu(II), and favorable lipophilicity for potential blood-brain barrier penetration. The alkyl carboxylate ester pendant arms offer up to 3 orders of magnitude higher binding affinity toward Cu(II) and enable the BFCs to form stable 64Cu-radiolabeled complexes. Among the five compounds tested, the 64Cu-YW-7 and 64Cu-YW-10 complexes exhibit strong and specific staining of amyloid plaques in ex vivo autoradiography studies. Importantly, these BFCs have promising partition coefficient (log Doct) values of 0.91-1.26 and show some brain uptake in biodistribution studies using CD-1 mice. Overall, these BFCs could serve as lead compounds for the development of positron emission tomography imaging agents for AD diagnosis.


Assuntos
Doença de Alzheimer/diagnóstico por imagem , Peptídeos beta-Amiloides/metabolismo , Quelantes/química , Quelantes/metabolismo , Radioisótopos de Cobre , Interações Hidrofóbicas e Hidrofílicas , Tomografia por Emissão de Pósitrons , Doença de Alzheimer/metabolismo , Barreira Hematoencefálica/metabolismo
12.
Nat Commun ; 12(1): 4669, 2021 08 03.
Artigo em Inglês | MEDLINE | ID: mdl-34344873

RESUMO

Diseases are a manifestation of how thousands of proteins interact. In several diseases, such as cancer and Alzheimer's disease, proteome-wide disturbances in protein-protein interactions are caused by alterations to chaperome scaffolds termed epichaperomes. Epichaperome-directed chemical probes may be useful for detecting and reversing defective chaperomes. Here we provide structural, biochemical, and functional insights into the discovery of epichaperome probes, with a focus on their use in central nervous system diseases. We demonstrate on-target activity and kinetic selectivity of a radiolabeled epichaperome probe in both cells and mice, together with a proof-of-principle in human patients in an exploratory single group assignment diagnostic study (ClinicalTrials.gov Identifier: NCT03371420). The clinical study is designed to determine the pharmacokinetic parameters and the incidence of adverse events in patients receiving a single microdose of the radiolabeled probe administered by intravenous injection. In sum, we introduce a discovery platform for brain-directed chemical probes that specifically modulate epichaperomes and provide proof-of-principle applications in their use in the detection, quantification, and modulation of the target in complex biological systems.


Assuntos
Sistema Nervoso Central/metabolismo , Chaperonas Moleculares/metabolismo , Mapeamento de Interação de Proteínas/instrumentação , Proteoma/metabolismo , Animais , Biomarcadores Tumorais/metabolismo , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/diagnóstico , Neoplasias Encefálicas/tratamento farmacológico , Neoplasias Encefálicas/metabolismo , Sobrevivência Celular/efeitos dos fármacos , Sistema Nervoso Central/efeitos dos fármacos , Glioblastoma/diagnóstico , Glioblastoma/metabolismo , Proteínas de Choque Térmico HSP90/antagonistas & inibidores , Proteínas de Choque Térmico HSP90/química , Proteínas de Choque Térmico HSP90/metabolismo , Humanos , Camundongos , Sondas Moleculares/química , Sondas Moleculares/farmacocinética , Sondas Moleculares/farmacologia , Sondas Moleculares/uso terapêutico , Tomografia por Emissão de Pósitrons
13.
Nat Commun ; 12(1): 4826, 2021 08 10.
Artigo em Inglês | MEDLINE | ID: mdl-34376696

RESUMO

Loss-of-function mutations in NEK1 gene, which encodes a serine/threonine kinase, are involved in human developmental disorders and ALS. Here we show that NEK1 regulates retromer-mediated endosomal trafficking by phosphorylating VPS26B. NEK1 deficiency disrupts endosomal trafficking of plasma membrane proteins and cerebral proteome homeostasis to promote mitochondrial and lysosomal dysfunction and aggregation of α-synuclein. The metabolic and proteomic defects of NEK1 deficiency disrupts the integrity of blood-brain barrier (BBB) by promoting lysosomal degradation of A20, a key modulator of RIPK1, thus sensitizing cerebrovascular endothelial cells to RIPK1-dependent apoptosis and necroptosis. Genetic inactivation of RIPK1 or metabolic rescue with ketogenic diet can prevent postnatal lethality and BBB damage in NEK1 deficient mice. Inhibition of RIPK1 reduces neuroinflammation and aggregation of α-synuclein in the brains of NEK1 deficient mice. Our study identifies a molecular mechanism by which retromer trafficking and metabolism regulates cerebrovascular integrity, cerebral proteome homeostasis and RIPK1-mediated neuroinflammation.


Assuntos
Barreira Hematoencefálica/metabolismo , Glucose/metabolismo , Complexos Multiproteicos/metabolismo , Quinase 1 Relacionada a NIMA/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/metabolismo , Animais , Animais Recém-Nascidos , Linhagem Celular , Células Cultivadas , Citocinas/genética , Citocinas/metabolismo , Ativação Enzimática , Células HEK293 , Humanos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Microglia/citologia , Microglia/metabolismo , Quinase 1 Relacionada a NIMA/genética , Necroptose/genética , Fosforilação , Transporte Proteico , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Serina-Treonina Quinases de Interação com Receptores/genética , Proteínas de Transporte Vesicular/genética , Proteínas de Transporte Vesicular/metabolismo
14.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299328

RESUMO

The blood-brain barrier (BBB) regulates the delivery of oxygen and important nutrients to the brain through active and passive transport and prevents neurotoxins from entering the brain. It also has a clearance function and removes carbon dioxide and toxic metabolites from the central nervous system (CNS). Several drugs are unable to cross the BBB and enter the CNS, adding complexity to drug screens targeting brain disorders. A well-functioning BBB is essential for maintaining healthy brain tissue, and a malfunction of the BBB, linked to its permeability, results in toxins and immune cells entering the CNS. This impairment is associated with a variety of neurological diseases, including Alzheimer's disease and Parkinson's disease. Here, we summarize current knowledge about the BBB in neurodegenerative diseases. Furthermore, we focus on recent progress of using human-induced pluripotent stem cell (iPSC)-derived models to study the BBB. We review the potential of novel stem cell-based platforms in modeling the BBB and address advances and key challenges of using stem cell technology in modeling the human BBB. Finally, we highlight future directions in this area.


Assuntos
Barreira Hematoencefálica/metabolismo , Encéfalo/citologia , Encéfalo/metabolismo , Células-Tronco Pluripotentes Induzidas/citologia , Células-Tronco Pluripotentes Induzidas/metabolismo , Doenças Neurodegenerativas/metabolismo , Animais , Barreira Hematoencefálica/citologia , Barreira Hematoencefálica/patologia , Encéfalo/irrigação sanguínea , Circulação Cerebrovascular , Humanos , Células-Tronco Pluripotentes Induzidas/patologia , Modelos Biológicos , Doenças Neurodegenerativas/patologia
15.
Neuroimage Clin ; 31: 102741, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34225019

RESUMO

OBJECTIVES: To determine if radiological evidence of blood brain barrier (BBB) dysfunction, measured using Dynamic Contrast Enhanced MRI (DCE-MRI), correlates with serum matrix metalloproteinase (MMP) levels in traumatic brain injury (TBI) patients, and thereby, identify a potential biomarker for BBB dysfunction. PATIENTS AND METHODS: 20 patients with a mild, moderate, or severe TBI underwent a DCE-MRI scan and BBB dysfunction was interpreted from KTrans. KTrans is a measure of capillary permeability that reflects the efflux of gadolinium contrast into the extra-cellar space. The serum samples were concurrently collected and later analysed for MMP-1, -2, -7, -9, and -10 levels using an ELISA assay. Statistical correlations between MMP levels and the KTrans value were calculated. Multiple testing was corrected using the Benjamin-Hochberg method to control the false-discovery rate (FDR). RESULTS: Serum MMP-1 values ranged from 1.5 to 49.6 ng/ml (12 ± 12.7), MMP-2 values from 58.3 to 174.1 ng/ml (109.5 ± 26.7), MMP-7 from 1.5 to 31.5 ng/mL (10 ± 7.4), MMP-9 from 128.6 to 1917.5 ng/ml (647.7 ± 749.6) and MMP-10 from 0.1 to 0.6 ng/mL (0.3 ± 0.2). Non-parametric Spearman correlation analysis on the data showed significant positive relationship between KTrans and MMP-7 (r = 0.55, p < 0.01). Correlations were also found between KTrans and MMP-1 (r = 0.74, p < 0.0002) and MMP-2 (r = 0.5, p < 0.025) but the actual MMP values were not above reference ranges, limiting the interpretation of results. Statistically significant correlations between KTrans and either MMP-9 or -10 were not found. CONCLUSION: This is the first study to show a correlation between DCE measures and MMP values in patients with a TBI. Our results support the suggestion that serum MMP-7 may be considered as a peripheral biomarker quantifying BBB dysfunction in TBI patients.


Assuntos
Lesões Encefálicas Traumáticas , Metaloproteinase 7 da Matriz/sangue , Barreira Hematoencefálica/metabolismo , Lesões Encefálicas Traumáticas/diagnóstico por imagem , Humanos , Imageamento por Ressonância Magnética , Metaloproteinase 9 da Matriz/metabolismo
16.
Int J Mol Sci ; 22(13)2021 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-34203143

RESUMO

2020 and 2021 have been unprecedented years due to the rapid spread of the modified severe acute respiratory syndrome coronavirus around the world. The coronavirus disease 2019 (COVID-19) causes atypical infiltrated pneumonia with many neurological symptoms, and major sleep changes. The exposure of people to stress, such as social confinement and changes in daily routines, is accompanied by various sleep disturbances, known as 'coronasomnia' phenomenon. Sleep disorders induce neuroinflammation, which promotes the blood-brain barrier (BBB) disruption and entry of antigens and inflammatory factors into the brain. Here, we review findings and trends in sleep research in 2020-2021, demonstrating how COVID-19 and sleep disorders can induce BBB leakage via neuroinflammation, which might contribute to the 'coronasomnia' phenomenon. The new studies suggest that the control of sleep hygiene and quality should be incorporated into the rehabilitation of COVID-19 patients. We also discuss perspective strategies for the prevention of COVID-19-related BBB disorders. We demonstrate that sleep might be a novel biomarker of BBB leakage, and the analysis of sleep EEG patterns can be a breakthrough non-invasive technology for diagnosis of the COVID-19-caused BBB disruption.


Assuntos
Encéfalo/metabolismo , COVID-19/patologia , Transtornos do Sono-Vigília/patologia , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/virologia , COVID-19/virologia , Ritmo Circadiano , Citocinas/metabolismo , Humanos , SARS-CoV-2/isolamento & purificação , Transtornos do Sono-Vigília/metabolismo
17.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299322

RESUMO

Clinical treatments for ischemic stroke are limited. Neural stem cell (NSC) transplantation can be a promising therapy. Clinically, ischemia and subsequent reperfusion lead to extensive neurovascular injury that involves inflammation, disruption of the blood-brain barrier, and brain cell death. NSCs exhibit multiple potentially therapeutic actions against neurovascular injury. Currently, tissue plasminogen activator (tPA) is the only FDA-approved clot-dissolving agent. While tPA's thrombolytic role within the vasculature is beneficial, tPA's non-thrombolytic deleterious effects aggravates neurovascular injury, restricting the treatment time window (time-sensitive) and tPA eligibility. Thus, new strategies are needed to mitigate tPA's detrimental effects and quickly mediate vascular repair after stroke. Up to date, clinical trials focus on the impact of stem cell therapy on neuro-restoration by delivering cells during the chronic stroke stage. Also, NSCs secrete factors that stimulate endogenous repair mechanisms for early-stage ischemic stroke. This review will present an integrated view of the preclinical perspectives of NSC transplantation as a promising treatment for neurovascular injury, with an emphasis on early-stage ischemic stroke. Further, this will highlight the impact of early sub-acute NSC delivery on improving short-term and long-term stroke outcomes.


Assuntos
AVC Isquêmico/terapia , Células-Tronco Neurais/transplante , Transplante de Células-Tronco/métodos , Animais , Barreira Hematoencefálica/metabolismo , Encéfalo/metabolismo , Isquemia Encefálica/metabolismo , Isquemia Encefálica/terapia , Fibrinolíticos/administração & dosagem , Humanos , AVC Isquêmico/metabolismo , Metaloendopeptidases/metabolismo , Traumatismo por Reperfusão/prevenção & controle , Traumatismo por Reperfusão/terapia , Transplante de Células-Tronco/tendências , Acidente Vascular Cerebral/metabolismo , Acidente Vascular Cerebral/terapia , Ativador de Plasminogênio Tecidual/uso terapêutico
18.
Int J Mol Sci ; 22(14)2021 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-34299316

RESUMO

Redox-active metal ions, Cu(I/II) and Fe(II/III), are essential biological molecules for the normal functioning of the brain, including oxidative metabolism, synaptic plasticity, myelination, and generation of neurotransmitters. Dyshomeostasis of these redox-active metal ions in the brain could cause Alzheimer's disease (AD). Thus, regulating the levels of Cu(I/II) and Fe(II/III) is necessary for normal brain function. To control the amounts of metal ions in the brain and understand the involvement of Cu(I/II) and Fe(II/III) in the pathogenesis of AD, many chemical agents have been developed. In addition, since toxic aggregates of amyloid-ß (Aß) have been proposed as one of the major causes of the disease, the mechanism of clearing Aß is also required to be investigated to reveal the etiology of AD clearly. Multiple metalloenzymes (e.g., neprilysin, insulin-degrading enzyme, and ADAM10) have been reported to have an important role in the degradation of Aß in the brain. These amyloid degrading enzymes (ADE) could interact with redox-active metal ions and affect the pathogenesis of AD. In this review, we introduce and summarize the roles, distributions, and transportations of Cu(I/II) and Fe(II/III), along with previously invented chelators, and the structures and functions of ADE in the brain, as well as their interrelationships.


Assuntos
Doença de Alzheimer/metabolismo , Amiloide/metabolismo , Encéfalo/metabolismo , Proteína ADAM10/metabolismo , Doença de Alzheimer/etiologia , Secretases da Proteína Precursora do Amiloide/metabolismo , Peptídeos beta-Amiloides/metabolismo , Barreira Hematoencefálica/metabolismo , Quelantes/metabolismo , Cobre/metabolismo , Humanos , Insulisina/metabolismo , Ferro/metabolismo , Proteínas de Membrana/metabolismo , Metais/metabolismo , Neprilisina/metabolismo , Oxirredução , Proteólise
19.
Int J Mol Sci ; 22(12)2021 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-34198485

RESUMO

Brain microvascular endothelial cells (BMECs) constitute the structural and functional basis for the blood-brain barrier (BBB) and play essential roles in bacterial meningitis. Although the BBB integrity regulation has been under extensive investigation, there is little knowledge regarding the roles of long non-coding RNAs (lncRNAs) in this event. The present study aimed to investigate the roles of one potential lncRNA, lncRSPH9-4, in meningitic E. coli infection of BMECs. LncRSPH9-4 was cytoplasm located and significantly up-regulated in meningitic E. coli-infected hBMECs. Electrical cell-substrate impedance sensing (ECIS) measurement and Western blot assay demonstrated lncRSPH9-4 overexpression in hBMECs mediated the BBB integrity disruption. By RNA-sequencing analysis, 639 mRNAs and 299 miRNAs were significantly differentiated in response to lncRSPH9-4 overexpression. We further found lncRSPH9-4 regulated the permeability in hBMECs by competitively sponging miR-17-5p, thereby increasing MMP3 expression, which targeted the intercellular tight junctions. Here we reported the infection-induced lncRSPH9-4 aggravated disruption of the tight junctions in hBMECs, probably through the miR-17-5p/MMP3 axis. This finding provides new insights into the function of lncRNAs in BBB integrity during meningitic E. coli infection and provides the novel nucleic acid targets for future treatment of bacterial meningitis.


Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Escherichia coli/fisiologia , Metaloproteinase 3 da Matriz/metabolismo , Meningites Bacterianas/genética , Meningites Bacterianas/microbiologia , MicroRNAs/metabolismo , RNA Longo não Codificante/metabolismo , Sequência de Bases , Citoplasma/metabolismo , Células Endoteliais/metabolismo , Células Endoteliais/microbiologia , Redes Reguladoras de Genes , Humanos , MicroRNAs/genética , Microvasos/patologia , Modelos Biológicos , Permeabilidade , RNA Longo não Codificante/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Transdução de Sinais , Junções Íntimas/metabolismo , Transcrição Genética , Regulação para Cima/genética
20.
Int J Mol Sci ; 22(13)2021 Jun 30.
Artigo em Inglês | MEDLINE | ID: mdl-34209088

RESUMO

Breast cancer (BC) brain metastases is a life-threatening condition to which accounts the poor understanding of BC cells' (BCCs) extravasation into the brain, precluding the development of preventive strategies. Thus, we aimed to unravel the players involved in the interaction between BCCs and blood-brain barrier (BBB) endothelial cells underlying BBB alterations and the transendothelial migration of malignant cells. We used brain microvascular endothelial cells (BMECs) as a BBB in vitro model, under conditions mimicking shear stress to improve in vivo-like BBB features. Mixed cultures were performed by the addition of fluorescently labelled BCCs to distinguish individual cell populations. BCC-BMEC interaction compromised BBB integrity, as revealed by junctional proteins (ß-catenin and zonula occludens-1) disruption and caveolae (caveolin-1) increase, reflecting paracellular and transcellular hyperpermeability, respectively. Both BMECs and BCCs presented alterations in the expression pattern of connexin 43, suggesting the involvement of the gap junction protein. Myosin light chain kinase and phosphorylated myosin light chain were upregulated, revealing the involvement of the endothelial cytoskeleton in the extravasation process. ß4-Integrin and focal adhesion kinase were colocalised in malignant cells, reflecting molecular interaction. Moreover, BCCs exhibited invadopodia, attesting migratory properties. Collectively, hub players involved in BC brain metastases formation were unveiled, disclosing possible therapeutic targets for metastases prevention.


Assuntos
Barreira Hematoencefálica/citologia , Neoplasias Encefálicas/secundário , Neoplasias da Mama/metabolismo , Redes Reguladoras de Genes , Animais , Barreira Hematoencefálica/metabolismo , Neoplasias Encefálicas/metabolismo , Caveolina 1/metabolismo , Técnicas de Cultura de Células , Linhagem Celular Tumoral , Conexina 43/metabolismo , Feminino , Regulação Neoplásica da Expressão Gênica , Humanos , Camundongos , Fosforilação , Resistência ao Cisalhamento , Migração Transendotelial e Transepitelial , Proteína da Zônula de Oclusão-1/metabolismo , beta Catenina/metabolismo
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