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1.
Brain Res ; 1822: 148669, 2024 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-37951562

RESUMO

Cerebral malaria (CM) pathogenesis is described as a multistep mechanism. In this context, monocytes have been implicated in CM pathogenesis by increasing the sequestration of infected red blood cells to the brain microvasculature. In disease, endothelial activation is followed by reduced monocyte rolling and increased adhesion. Nowadays, an important challenge is to identify potential pro-inflammatory stimuli that can modulate monocytes behavior. Our group have demonstrated that bradykinin (BK), a pro-inflammatory peptide involved in CM, is generated during the erythrocytic cycle of P. falciparum and is detected in culture supernatant (conditioned medium). Herein we investigated the role of BK in the adhesion of monocytes to endothelial cells of blood brain barrier (BBB). To address this issue human monocytic cell line (THP-1) and human brain microvascular endothelial cells (hBMECs) were used. It was observed that 20% conditioned medium from P. falciparum infected erythrocytes (Pf-iRBC sup) increased the adhesion of THP-1 cells to hBMECs. This effect was mediated by BK through the activation of B2 and B1 receptors and involves the increase in ICAM-1 expression in THP-1 cells. Additionally, it was observed that angiotensin-converting enzyme (ACE) inhibitor, captopril, enhanced the effect of both BK and Pf-iRBC sup on THP-1 adhesion. Together these data show that BK, generated during the erythrocytic cycle of P. falciparum, could play an important role in adhesion of monocytes in endothelial cells lining the BBB.


Assuntos
Barreira Hematoencefálica , Bradicinina , Adesão Celular , Malária Cerebral , Malária Falciparum , Plasmodium falciparum , Humanos , Bradicinina/metabolismo , Adesão Celular/fisiologia , Meios de Cultivo Condicionados/farmacologia , Células Endoteliais/efeitos dos fármacos , Células Endoteliais/fisiologia , Eritrócitos/parasitologia , Malária Cerebral/metabolismo , Malária Cerebral/parasitologia , Malária Falciparum/metabolismo , Malária Falciparum/parasitologia , Monócitos/fisiologia , Plasmodium falciparum/fisiologia , Barreira Hematoencefálica/fisiopatologia
2.
Ann Med ; 55(2): 2251145, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37634059

RESUMO

Background: As a chronic and progressive neurodegenerative disease, Parkinson's disease (PD) still lacks effective and safe targeted drug therapy. Low-intensity focused ultrasound (LIFU), a new method to stimulate the brain and open the blood-brain barrier (BBB), has been widely concerned by PD researchers due to its non-invasive characteristics.Methods: PubMed was searched for the past 10 years using the terms 'focused ultrasound', 'transcranial ultrasound', 'pulse ultrasound', and 'Parkinson's disease'. Relevant citations were selected from the authors' references. After excluding articles describing high-intensity focused ultrasound or non-Parkinson's disease applications, we found more than 100 full-text analyses for pooled analysis.Results: Current preclinical studies have shown that LIFU could improve PD motor symptoms by regulating microglia activation, increasing neurotrophic factors, reducing oxidative stress, and promoting nerve repair and regeneration, while LIFU combined with microbubbles (MBs) can promote drugs to cross the BBB, which may become a new direction of PD treatment. Therefore, finding an efficient drug carrier system is the top priority of applying LIFU with MBs to deliver drugs.Conclusions: This article aims to review neuro-modulatory effect of LIFU and the possible biophysical mechanism in the treatment of PD, summarize the latest progress in delivering vehicles with MBs, and discuss its advantages and limitations.


Neuro-modulatory effects of LIFU at the cellular or molecular level.Opening the BBB through the combination of LIFU and MBs.Biophysical mechanism of LIFU.


Assuntos
Doença de Parkinson , Ultrassonografia , Humanos , Encéfalo , Doença de Parkinson/terapia , Barreira Hematoencefálica/fisiopatologia
4.
Nat Neurosci ; 25(8): 1034-1048, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35879464

RESUMO

Frontotemporal dementia (FTD) is the second most prevalent form of early-onset dementia, affecting predominantly frontal and temporal cerebral lobes. Heterozygous mutations in the progranulin gene (GRN) cause autosomal-dominant FTD (FTD-GRN), associated with TDP-43 inclusions, neuronal loss, axonal degeneration and gliosis, but FTD-GRN pathogenesis is largely unresolved. Here we report single-nucleus RNA sequencing of microglia, astrocytes and the neurovasculature from frontal, temporal and occipital cortical tissue from control and FTD-GRN brains. We show that fibroblast and mesenchymal cell numbers were enriched in FTD-GRN, and we identified disease-associated subtypes of astrocytes and endothelial cells. Expression of gene modules associated with blood-brain barrier (BBB) dysfunction was significantly enriched in FTD-GRN endothelial cells. The vasculature supportive function and capillary coverage by pericytes was reduced in FTD-GRN tissue, with increased and hypertrophic vascularization and an enrichment of perivascular T cells. Our results indicate a perturbed BBB and suggest that the neurovascular unit is severely affected in FTD-GRN.


Assuntos
Demência Frontotemporal , Progranulinas , Barreira Hematoencefálica/fisiopatologia , Células Endoteliais/patologia , Demência Frontotemporal/genética , Demência Frontotemporal/patologia , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Mutação , Progranulinas/genética , Análise de Sequência de RNA , Lobo Temporal/patologia
5.
Proc Natl Acad Sci U S A ; 119(15): e2113310119, 2022 04 12.
Artigo em Inglês | MEDLINE | ID: mdl-35377817

RESUMO

Gestational maternal immune activation (MIA) in mice induces persistent brain microglial activation and a range of neuropathologies in the adult offspring. Although long-term phenotypes are well documented, how MIA in utero leads to persistent brain inflammation is not well understood. Here, we found that offspring of mothers treated with polyriboinosinic­polyribocytidylic acid [poly(I:C)] to induce MIA at gestational day 13 exhibit blood­brain barrier (BBB) dysfunction throughout life. Live MRI in utero revealed fetal BBB hyperpermeability 2 d after MIA. Decreased pericyte­endothelium coupling in cerebral blood vessels and increased microglial activation were found in fetal and 1- and 6-mo-old offspring brains. The long-lasting disruptions result from abnormal prenatal BBB formation, driven by increased proliferation of cyclooxygenase-2 (COX2; Ptgs2)-expressing microglia in fetal brain parenchyma and perivascular spaces. Targeted deletion of the Ptgs2 gene in fetal myeloid cells or treatment with the inhibitor celecoxib 24 h after immune activation prevented microglial proliferation and disruption of BBB formation and function, showing that prenatal COX2 activation is a causal pathway of MIA effects. Thus, gestational MIA disrupts fetal BBB formation, inducing persistent BBB dysfunction, which promotes microglial overactivation and behavioral alterations across the offspring life span. Taken together, the data suggest that gestational MIA disruption of BBB formation could be an etiological contributor to neuropsychiatric disorders.


Assuntos
Barreira Hematoencefálica , Ciclo-Oxigenase 2 , Encefalite , Troca Materno-Fetal , Microglia , Efeitos Tardios da Exposição Pré-Natal , Animais , Barreira Hematoencefálica/anormalidades , Barreira Hematoencefálica/fisiopatologia , Celecoxib/farmacologia , Ciclo-Oxigenase 2/genética , Ciclo-Oxigenase 2/metabolismo , Inibidores de Ciclo-Oxigenase 2/farmacologia , Encefalite/imunologia , Feminino , Deleção de Genes , Troca Materno-Fetal/imunologia , Camundongos , Microglia/enzimologia , Poli I-C/imunologia , Gravidez , Efeitos Tardios da Exposição Pré-Natal/imunologia
6.
Bioengineered ; 13(2): 4441-4454, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35112992

RESUMO

Blood-brain-barrier (BBB) disruption is an important pathological characteristic of ischemic stroke (IS) and mainly results from dysfunction of brain vascular endothelial cells and tight junctions. Zebularine is a novel inhibitor of DNA methyltransferase (DNMT). Here, we assessed its effects on BBB disruption in IS. Firstly, we reported that Zebularine maintained BBB integrity in middle cerebral artery occlusion (MCAO) mice by increasing the expressions of zona occludens-1 (ZO-1) and vascular endothelial (VE)-cadherin. Importantly, we found that Zebularine reduced the production of pro-inflammatory cytokines, attenuated brain edema, and improved neurological deficits. In in vitro experiments, the bEnd.3 brain endothelial cells were exposed to oxygen and glucose deprivation/reoxygenation (OGD/R), and the protective effects of Zebularine were assessed. Our findings demonstrated that Zebularine prevented OGD/R-induced cytotoxicity by reducing the release of lactate dehydrogenase (LDH). Additionally, Zebularine protected bEnd.3 cells against OGD/R-induced hyper-permeability and reduction of trans-endothelial electrical resistance (TEER). Notably, we found that treatment with Zebularine activated the Adenosine 5'-monophosphate (AMP)-activated protein kinase (AMPK) pathway by increasing the phosphorylation of adenosine monophosphate-activated protein kinase α (AMPKα). Blockage of AMPKα using its specific inhibitor compound C abolished the beneficial effects of Zebularine in mitigating endothelial hyper-permeability by reducing the expressions of ZO-1 and VE-cadherin. These findings suggest that the protective effects of Zebularine against OGD/R-induced endothelial hyper-permeability are mediated by the activation of AMPKα. In conclusion, our study sheds light on the potential application of Zebularine in the treatment of IS.


Assuntos
Barreira Hematoencefálica/efeitos dos fármacos , Caderinas/genética , Citidina/análogos & derivados , Substâncias Protetoras , Proteína da Zônula de Oclusão-1/genética , Proteínas Quinases Ativadas por AMP/metabolismo , Animais , Barreira Hematoencefálica/fisiopatologia , Caderinas/metabolismo , Citidina/química , Citidina/farmacologia , Endotélio Vascular/citologia , Inflamação/metabolismo , Camundongos , Substâncias Protetoras/química , Substâncias Protetoras/farmacologia , Acidente Vascular Cerebral/metabolismo , Proteína da Zônula de Oclusão-1/metabolismo
7.
Sci Rep ; 12(1): 2186, 2022 02 09.
Artigo em Inglês | MEDLINE | ID: mdl-35140324

RESUMO

We compared the cut-off and prognostic value of serum neuron-specific enolase (NSE) between groups with and without severe blood-brain barrier (BBB) disruption to reveal that a cause of various serum NSE cut-off value for neurological prognosis is severe BBB disruption in out-of-hospital cardiac arrest (OHCA) patients underwent target temperature management (TTM). This was a prospective, single-centre study conducted from January 2019 to June 2021. Severe BBB disruption was indicated using cerebrospinal fluid-serum albumin quotient values > 0.02. The area under the receiver operating characteristic curve of serum NSE obtained on day 3 of hospitalisation to predict poor outcomes was used. In patients with poor neurologic outcomes, serum NSE in those with severe BBB disruption was higher than in those without (P = 0.006). A serum NSE cut-off value of 40.4 µg/L for poor outcomes in patients without severe BBB disruption had a sensitivity of 41.7% and a specificity of 96.0%, whereas a cut-off value of 34.6 µg/L in those with severe BBB disruption had a sensitivity of 86.4% and a specificity of 100.0%. We demonstrated that the cut-off and prognostic value of serum NSE were heterogeneous, depending on severe BBB disruption in OHCA patients treated with TTM.


Assuntos
Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Doenças do Sistema Nervoso/diagnóstico , Parada Cardíaca Extra-Hospitalar/sangue , Parada Cardíaca Extra-Hospitalar/diagnóstico , Fosfopiruvato Hidratase/sangue , Adulto , Idoso , Biomarcadores/sangue , Correlação de Dados , Técnicas de Diagnóstico Neurológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/etiologia , Parada Cardíaca Extra-Hospitalar/complicações , Prognóstico , Estudos Prospectivos , Curva ROC , Albumina Sérica/líquido cefalorraquidiano
8.
Commun Biol ; 5(1): 74, 2022 01 20.
Artigo em Inglês | MEDLINE | ID: mdl-35058552

RESUMO

Acute ischemic stroke triggers complex systemic pathological responses for which the exploration of drug resources remains a challenge. Wasp venom extracted from Vespa magnifica (Smith, 1852) is most commonly used to treat rheumatoid arthritis as well as neurological disorders. Vespakinin-M (VK), a natural peptide from wasp venom, has remained largely unexplored for stroke. Herein, we first confirmed the structure, stability, toxicity and distribution of VK as well as its penetration into the blood-brain barrier. VK (150 and 300 µg/kg, i.p.) was administered to improve stroke constructed by middle cerebral artery occlusion in mice. Our results indicate that VK promote functional recovery in mice after ischemia stroke, including an improvement of neurological impairment, reduction of infarct volume, maintenance of blood-brain barrier integrity, and an obstruction of the inflammatory response and oxidative stress. In addition, VK treatment led to reduced neuroinflammation and apoptosis associated with the activation of PI3K-AKT and inhibition of IκBα-NF-κB signaling pathways. Simultaneously, we confirmed that VK can combine with bradykinin receptor 2 (B2R) as detected by molecular docking, the B2R antagonist HOE140 could counteract the neuro-protective effects of VK on stroke in mice. Overall, targeting the VK-B2R interaction can be considered as a practical strategy for stroke therapy.


Assuntos
Bradicinina/análogos & derivados , AVC Isquêmico/tratamento farmacológico , Fármacos Neuroprotetores/farmacologia , Recuperação de Função Fisiológica/efeitos dos fármacos , Vespas/química , Animais , Barreira Hematoencefálica/fisiopatologia , Bradicinina/química , Bradicinina/farmacologia , Proteínas de Insetos/química , Proteínas de Insetos/farmacologia , Masculino , Camundongos , Fármacos Neuroprotetores/química
9.
Am J Physiol Heart Circ Physiol ; 322(2): H246-H259, 2022 02 01.
Artigo em Inglês | MEDLINE | ID: mdl-34951541

RESUMO

Diabetes mellitus (DM) is a leading risk factor for age-related dementia, but the mechanisms involved are not well understood. We previously discovered that hyperglycemia induced impaired myogenic response (MR) and cerebral blood flow (CBF) autoregulation in 18-mo-old DM rats associated with blood-brain barrier (BBB) leakage, impaired neurovascular coupling, and cognitive impairment. In the present study, we examined whether reducing plasma glucose with a sodium-glucose cotransporter-2 inhibitor (SGLT2i) luseogliflozin can ameliorate cerebral vascular and cognitive function in diabetic rats. Plasma glucose and HbA1c levels of 18-mo-old DM rats were reduced, and blood pressure was not altered after treatment with luseogliflozin. SGLT2i treatment restored the impaired MR of middle cerebral arteries (MCAs) and parenchymal arterioles and surface and deep cortical CBF autoregulation in DM rats. Luseogliflozin treatment also rescued neurovascular uncoupling, reduced BBB leakage and cognitive deficits in DM rats. However, SGLT2i did not have direct constrictive effects on vascular smooth muscle cells and MCAs isolated from normal rats, although it decreased reactive oxygen species production in cerebral vessels of DM rats. These results provide evidence that normalization of hyperglycemia with an SGLT2i can reverse cerebrovascular dysfunction and cognitive impairments in rats with long-standing hyperglycemia, possibly by ameliorating oxidative stress-caused vascular damage.NEW & NOTEWORTHY This study demonstrates that luseogliflozin, a sodium-glucose cotransporter-2 inhibitor, improved CBF autoregulation in association with reduced vascular oxidative stress and AGEs production in the cerebrovasculature of 18-mo-old DM rats. SGLT2i also prevented BBB leakage, impaired functional hyperemia, neurodegeneration, and cognitive impairment seen in DM rats. Luseogliflozin did not have direct constrictive effects on VSMCs and MCAs isolated from normal rats. These results provide evidence that normalization of hyperglycemia with an SGLT2i can reverse cerebrovascular dysfunction and cognitive impairments in rats with long-standing hyperglycemia, possibly by ameliorating oxidative stress-caused vascular damage.


Assuntos
Demência Vascular/tratamento farmacológico , Angiopatias Diabéticas/tratamento farmacológico , Inibidores do Transportador 2 de Sódio-Glicose/uso terapêutico , Sorbitol/análogos & derivados , Animais , Arteríolas/efeitos dos fármacos , Arteríolas/fisiopatologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Células Cultivadas , Circulação Cerebrovascular , Cognição , Masculino , Artéria Cerebral Média/efeitos dos fármacos , Artéria Cerebral Média/fisiopatologia , Ratos , Ratos Sprague-Dawley , Inibidores do Transportador 2 de Sódio-Glicose/farmacologia , Sorbitol/farmacologia , Sorbitol/uso terapêutico
10.
Artigo em Inglês | MEDLINE | ID: mdl-34725263

RESUMO

BACKGROUND AND OBJECTIVES: To analyze (1) the effect of immunoglobulin G (IgG) from patients with anti-myelin oligodendrocyte glycoprotein antibody (MOG-Ab)-associated disorder on the blood-brain barrier (BBB) endothelial cells and (2) the positivity of glucose-regulated protein 78 (GRP78) antibodies in MOG-Ab-associated disorders. METHODS: IgG was purified from sera with patients with MOG-Ab-associated disorder in the acute phase (acute MOG, n = 15), in the stable stage (stable MOG, n = 14), healthy controls (HCs, n = 9), and disease controls (DCs, n = 27). Human brain microvascular endothelial cells (BMECs) were incubated with IgG, and the number of nuclear NF-κB p65-positive cells in BMECs using high-content imaging system and the quantitative messenger RNA change in gene expression over the whole transcriptome using RNA-seq were analyzed. GRP78 antibodies from patient IgGs were detected by Western blotting. RESULTS: IgG in the acute MOG group significantly induced the nuclear translocation of NF-κB and increased the vascular cell adhesion molecule 1/intercellular adhesion molecule 1 expression/permeability of 10-kDa dextran compared with that from the stable MOG and HC/DC groups. RNA-seq and pathway analysis revealed that NF-κB signaling and oxidative stress (NQO1) play key roles. The NQO1 and Nrf2 protein amounts were significantly decreased after exposure to IgG in the acute MOG group. The rate of GRP78 antibody positivity in the acute MOG group (10/15, 67% [95% confidence interval, 38%-88%]) was significantly higher than that in the stable MOG group (5/14, 36% [13%-65%]), multiple sclerosis group (4/29, 14% [4%-32%]), the DCs (3/27, 11% [2%-29%]), or HCs (0/9, 0%). Removal of GRP78 antibodies from MOG-IgG reduced the effect on NF-κB nuclear translocation and increased permeability. DISCUSSION: GRP78 antibodies may be associated with BBB dysfunction in MOG-Ab-associated disorder.


Assuntos
Autoanticorpos/sangue , Doenças Autoimunes do Sistema Nervoso/imunologia , Doenças Autoimunes do Sistema Nervoso/fisiopatologia , Barreira Hematoencefálica/fisiopatologia , Chaperona BiP do Retículo Endoplasmático/imunologia , Glicoproteína Mielina-Oligodendrócito/imunologia , Adolescente , Adulto , Idoso , Doenças Autoimunes do Sistema Nervoso/sangue , Pré-Escolar , Células Endoteliais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Adulto Jovem
11.
Int Rev Neurobiol ; 161: 209-249, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-34801170

RESUMO

Alcohol is the most commonly used drug of abuse in the world and binge drinking is especially harmful to the brain, though the mechanisms by which alcohol compromises overall brain health remain somewhat elusive. A number of brain diseases and pathological states are accompanied by perturbations in Blood-Brain Barrier (BBB) function, ultimately exacerbating disease progression. The BBB is critical for coordinating activity between the peripheral immune system and the brain. Importantly, BBB integrity is responsive to circulating cytokines and other immune-related signaling molecules, which are powerfully modulated by alcohol exposure. This review will highlight key cellular components of the BBB; discuss mechanisms by which permeability is achieved; offer insight into methodological approaches for assessing BBB integrity; and forecast how alcohol-induced changes in the peripheral and central immune systems might influence BBB function in individuals with a history of binge drinking and ultimately Alcohol Use Disorders (AUD).


Assuntos
Barreira Hematoencefálica , Etanol , Inflamação , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Etanol/toxicidade , Humanos , Inflamação/induzido quimicamente
12.
MAGMA ; 35(1): 17-27, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-34910266

RESUMO

OBJECTIVE: To evaluate the feasibility of intravoxel incoherent motion (IVIM) in assessing blood-brain barrier (BBB) integrity and microvasculature in tumoral tissue of glioma patients. METHODS: Images from 8 high-grade and 4 low-grade glioma patients were acquired on a 3 T MRI scanner. Acquisition protocol included pre- and post-contrast T1- and T2-weighted imaging, FLAIR, dynamic susceptibility contrast (DSC), and susceptibility-weighted imaging (SWI). In addition, IVIM was acquired with 15 b-values and fitted under the non-negative least square (NNLS) model to output the diffusion (D) and pseudo-diffusion (D*) coefficients, perfusion fraction (f), and f times D* (fD*) maps. RESULTS: IVIM perfusion-related maps were sensitive to (1) blood flow and perfusion alterations within the microvasculature of brain tumors, in agreement with intra-tumoral susceptibility signal (ITSS); (2) enhancing areas of BBB breakdown in agreement with DSC maps as well as areas of BBB abnormality that was not detected on DSC maps; (3) enhancing perfusion changes within edemas; (4) detecting early foci of increased perfusion within low-grade gliomas. CONCLUSION: The results suggest IVIM may be a promising approach to delineate tumor extension and progression in size, and to predict histological grade, which are clinically relevant information that characterize tumors and guide therapeutic decisions in patients with glioma.


Assuntos
Barreira Hematoencefálica , Glioma , Microvasos , Barreira Hematoencefálica/diagnóstico por imagem , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Imagem de Difusão por Ressonância Magnética/métodos , Estudos de Viabilidade , Glioma/irrigação sanguínea , Glioma/diagnóstico por imagem , Glioma/patologia , Glioma/fisiopatologia , Humanos , Microcirculação , Microvasos/diagnóstico por imagem , Microvasos/patologia , Movimento (Física)
13.
Anal Biochem ; 636: 114387, 2022 01 01.
Artigo em Inglês | MEDLINE | ID: mdl-34537182

RESUMO

Non-alcoholic fatty liver disease (NAFLD) is a multisystem disease, which has been classified as an emerging epidemic not only confined to liver-related morbidity and mortality. It is also becoming apparent that NAFLD is associated with moderate cerebral dysfunction and cognitive decline. A possible link between NAFLD and Alzheimer's disease (AD) has only recently been proposed due to the multiple shared genes and pathological mechanisms contributing to the development of these conditions. Although AD is a progressive neurodegenerative disease, the exact pathophysiological mechanism remains ambiguous and similarly to NAFLD, currently available pharmacological therapies have mostly failed in clinical trials. In addition to the usual suspects (inflammation, oxidative stress, blood-brain barrier alterations and ageing) that could contribute to the NAFLD-induced development and progression of AD, changes in the vasculature, cerebral perfusion and waste clearance could be the missing link between these two diseases. Here, we review the most recent literature linking NAFLD and AD, focusing on cerebrovascular alterations and the brain's clearance system as risk factors involved in the development and progression of AD, with the aim of promoting further research using neuroimaging techniques and new mechanism-based therapeutic interventions.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer , Transtornos Cerebrovasculares , Hepatopatia Gordurosa não Alcoólica , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Doença de Alzheimer/fisiopatologia , Animais , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Transtornos Cerebrovasculares/etiologia , Transtornos Cerebrovasculares/metabolismo , Transtornos Cerebrovasculares/fisiopatologia , Humanos , Inflamação/metabolismo , Inflamação/fisiopatologia , Hepatopatia Gordurosa não Alcoólica/complicações , Hepatopatia Gordurosa não Alcoólica/metabolismo , Hepatopatia Gordurosa não Alcoólica/fisiopatologia , Estresse Oxidativo , Fatores de Risco
14.
Proc Natl Acad Sci U S A ; 118(45)2021 11 09.
Artigo em Inglês | MEDLINE | ID: mdl-34728566

RESUMO

Drainage of interstitial fluid and solutes from the brainstem has not been well studied. To map one drainage pathway in the human brainstem, we took advantage of the focal blood-brain barrier disruption occurring in a multiple sclerosis brainstem lesion, coupled with intravenous injection of gadolinium, which simulates an intraparenchymal injection of gadolinium tracer within the restricted confines of this small brain region. Using high-resolution MRI, we show how it is possible for interstitial fluid to drain into the adjacent trigeminal and oculomotor nerves, in keeping with a pathway of communication between the extracellular spaces of the brainstem and cranial nerve parenchyma.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Tronco Encefálico/fisiologia , Nervos Cranianos/fisiologia , Líquido Extracelular/fisiologia , Esclerose Múltipla/fisiopatologia , Adulto , Barreira Hematoencefálica/diagnóstico por imagem , Nervos Cranianos/diagnóstico por imagem , Gadolínio , Humanos , Imageamento por Ressonância Magnética , Masculino
15.
Fluids Barriers CNS ; 18(1): 50, 2021 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-34789271

RESUMO

BACKGROUND: Chronic mild hypoxia (CMH, 8% O2) stimulates robust vascular remodelling in the brain, but it also triggers transient vascular disruption. This raises the fundamental question: is the vascular leak an unwanted side-effect of angiogenic remodelling or is it a pathological response, unrelated to endothelial proliferation, in which declining oxygen levels trigger endothelial dysfunction? METHODS: To answer this question, mice were exposed to CMH (8% O2) for periods up to 14 days, after which, brain tissue was examined by immunofluorescence (IF) to determine which type of blood vessel (arteriole, capillary or venule) was most commonly associated with endothelial proliferation and vascular leak and how this correlated with tight junction protein expression. Vascular perfusion was examined using DiI. Data were analysed using one-way analysis of variance (ANOVA) followed by Tukey's multiple comparison post-hoc test. RESULTS: The following was observed: (1) most endothelial proliferation and extravascular fibrinogen leak occurred in capillaries and to a lesser degree in venules, (2) much to our surprise, endothelial proliferation and extravascular fibrinogen leak never colocalized, (3) interestingly however, endothelial proliferation was strongly associated with an intravascular fibrinogen staining pattern not seen in stable blood vessels, (4) DiI perfusion studies revealed that angiogenic vessels were adequately perfused, suggesting that fibrinogen retention in angiogenic vessels is not due to temporary closure of the vessel, but more likely because fibrinogen is retained within the vessel wall, (5) bromodeoxyuridine (BrdU) labelling as a means to more permanently label proliferating endothelial cells, confirmed lack of any connection between endothelial proliferation and extravascular fibrinogen leak, while (6) in contrast, proliferating microglia were detected within extravascular leaks. CONCLUSIONS: Taken together, our findings support the concept that in the short-term, hypoxia-induced endothelial proliferation triggers transient fibrinogen deposition within the walls of angiogenic blood vessels, but no overt vascular leak occurs in these vessels. Importantly, endothelial proliferation and extravascular fibrinogen leaks never co-localize, demonstrating that extravascular leak is not an unwanted side-effect of angiogenic endothelial proliferation, but rather a dysfunctional vascular response to hypoxia that occurs in a distinct group of non-angiogenic blood vessels.


Assuntos
Barreira Hematoencefálica/fisiopatologia , Transtornos Cerebrovasculares/fisiopatologia , Endotélio Vascular/fisiopatologia , Hipóxia/fisiopatologia , Neovascularização Patológica/fisiopatologia , Remodelação Vascular/fisiologia , Animais , Transtornos Cerebrovasculares/etiologia , Modelos Animais de Doenças , Feminino , Hipóxia/complicações , Masculino , Camundongos , Camundongos Endogâmicos C57BL
16.
FEBS Lett ; 595(23): 2854-2871, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34757622

RESUMO

SARS-CoV-2 has infected hundreds of millions of people with over four million dead, resulting in one of the worst global pandemics in recent history. Neurological symptoms associated with COVID-19 include anosmia, ageusia, headaches, confusion, delirium, and strokes. These may manifest due to viral entry into the central nervous system (CNS) through the blood-brain barrier (BBB) by means of ill-defined mechanisms. Here, we summarize the abilities of SARS-CoV-2 and other neurotropic RNA viruses, including Zika virus and Nipah virus, to cross the BBB into the CNS, highlighting the role of magnetic resonance imaging (MRI) in assessing presence and severity of brain structural changes in COVID-19 patients. We present new insight into key mutations in SARS-CoV-2 variants B.1.1.7 (P681H) and B.1.617.2 (P681R), which may impact on neuropilin 1 (NRP1) binding and CNS invasion. We postulate that SARS-CoV-2 may infect both peripheral cells capable of crossing the BBB and brain endothelial cells to traverse the BBB and spread into the brain. COVID-19 patients can be followed up with MRI modalities to better understand the long-term effects of COVID-19 on the brain.


Assuntos
Barreira Hematoencefálica , Infecções por Henipavirus , Vírus Nipah , SARS-CoV-2 , Infecção por Zika virus , Zika virus , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/fisiopatologia , Barreira Hematoencefálica/virologia , COVID-19/epidemiologia , COVID-19/genética , COVID-19/metabolismo , COVID-19/fisiopatologia , Infecções por Henipavirus/epidemiologia , Infecções por Henipavirus/genética , Infecções por Henipavirus/metabolismo , Infecções por Henipavirus/fisiopatologia , Humanos , Mutação , Vírus Nipah/genética , Vírus Nipah/metabolismo , SARS-CoV-2/genética , SARS-CoV-2/metabolismo , Zika virus/genética , Zika virus/metabolismo , Infecção por Zika virus/epidemiologia , Infecção por Zika virus/genética , Infecção por Zika virus/metabolismo , Infecção por Zika virus/fisiopatologia
17.
Molecules ; 26(19)2021 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-34641582

RESUMO

The accumulation of amyloid plaques, or misfolded fragments of proteins, leads to the development of a condition known as amyloidosis, which is clinically recognized as a systemic disease. Amyloidosis plays a special role in the pathogenesis of neurodegenerative diseases such as Alzheimer's disease (AD), Parkinson's disease, and rheumatoid arthritis (RA). The occurrence of amyloidosis correlates with the aging process of the organism, and since nowadays, old age is determined by the comfort of functioning and the elimination of unpleasant disease symptoms in the elderly, exposure to this subject is justified. In Alzheimer's disease, amyloid plaques negatively affect glutaminergic and cholinergic transmission and loss of sympathetic protein, while in RA, amyloids stimulated by the activity of the immune system affect the degradation of the osteoarticular bond. The following monograph draws attention to the over-reactivity of the immune system in AD and RA, describes the functionality of the blood-brain barrier as an intermediary medium between RA and AD, and indicates the direction of research to date, focusing on determining the relationship and the cause-effect link between these disorders. The paper presents possible directions for the treatment of amyloidosis, with particular emphasis on innovative therapies.


Assuntos
Envelhecimento/metabolismo , Doença de Alzheimer/fisiopatologia , Amiloidose/fisiopatologia , Artrite Reumatoide/fisiopatologia , Sistema Imunitário/fisiopatologia , Doença de Parkinson/fisiopatologia , Placa Amiloide/fisiopatologia , Barreira Hematoencefálica/fisiopatologia , Encéfalo/metabolismo , Citocinas/metabolismo , Humanos
18.
Artigo em Inglês | MEDLINE | ID: mdl-34667128

RESUMO

BACKGROUND AND OBJECTIVES: To evaluate the pathophysiology of neuromyelitis optica spectrum disorder (NMOSD) and the therapeutic mechanism and levels of interleukin-6 (IL-6) blockade (satralizumab), especially with respect to blood-brain barrier (BBB) disruption with the new in vitro and ex vivo human BBB models and in vivo model. METHODS: We constructed new static in vitro and flow-based ex vivo models for evaluating continued barrier function, leukocyte transmigration, and intracerebral transferability of neuromyelitis optica-immunoglobulin G (NMO-IgG) and satralizumab across the BBB using the newly established triple coculture system that are specialized to closely mimic endothelial cell contact of pericytes and endfeet of astrocytes. In the in vivo study, we assessed the effects of an anti-IL-6 receptor antibody for mice (MR16-1) on in vivo BBB disruption in mice with experimental autoimmune encephalomyelitis in which IL-6 concentration in the spinal cord dramatically increases. RESULTS: In vitro and ex vivo experiments demonstrated that NMO-IgG increased intracerebral transferability of satralizumab and NMO-IgG and that satralizumab suppressed the NMO-IgG-induced transmigration of T cells and barrier dysfunction. In the in vivo study, the blockade of IL-6 signaling suppressed the migration of T cells into the spinal cord and prevented the increased BBB permeability. DISCUSSION: These results suggest that (1) our triple-cultured in vitro and in ex vivo BBB models are ideal for evaluating barrier function, leukocyte transmigration, and intracerebral transferability; (2) NMO-IgG increased the intracerebral transferability of NMO-IgG via decreasing barrier function and induced secretion of IL-6 from astrocytes causing more dysfunction of the barrier and disrupting controlled cellular infiltration; and (3) satralizumab, which can pass through the BBB in the presence of NMO-IgG, suppresses the BBB dysfunction and the infiltration of inflammatory cells, leading to prevention of onset of NMOSD.


Assuntos
Anticorpos Bloqueadores/farmacologia , Autoanticorpos/farmacologia , Barreira Hematoencefálica , Encefalomielite Autoimune Experimental/imunologia , Interleucina-6/imunologia , Neuromielite Óptica , Animais , Anticorpos Monoclonais Humanizados/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Barreira Hematoencefálica/fisiopatologia , Células Cultivadas , Técnicas de Cocultura , Modelos Animais de Doenças , Feminino , Humanos , Imunoglobulina G , Camundongos , Camundongos Endogâmicos C57BL , Neuromielite Óptica/imunologia , Neuromielite Óptica/prevenção & controle
19.
Biomed Pharmacother ; 143: 112200, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34649342

RESUMO

The pathology of cerebrovascular disorders takes an important role in traumatic brain injury (TBI) by increasing intracranial pressure. Fibroblast growth factor 20 (FGF20) is a brain-derived neurotrophic factor, that has been shown to play an important role in the survival of dopaminergic neurons and the treatment of Parkinson's disease (PD). However, little is known about the role of FGF20 in the treatment of TBI and its underlying mechanism. The purpose of this study was to evaluate the protective effect of recombinant human FGF20 (rhFGF20) on protecting cerebral blood vessels after TBI. In this study, we indicated that rhFGF20 could reduce brain edema, Evans blue penetration and upregulated the expression of blood-brain barrier (BBB)-related tight junction (TJ) proteins, exerting a protective effect on the BBB in vivo after TBI. In the TBI repair phase, rhFGF20 promoted angiogenesis, neurological and cognitive function recovery. In tumor necrosis factor-α (TNF-α)-induced human brain microvascular endothelial cells (hCMEC/D3), an in vitro BBB disruption model, rhFGF20 reversed the impairment in cell migration and tube formation induced by TNF-α. Moreover, in both the TBI mouse model and the in vitro model, rhFGF20 increased the expression of ß-catenin and GSK3ß, which are the two key regulators in the Wnt/ß-catenin signaling pathway. In addition, the Wnt/ß-catenin inhibitor IWR-1-endo significantly reversed the effects of rhFGF20. These results indicate that rhFGF20 may prevent vascular repair and angiogenesis through the Wnt/ß-catenin pathway.


Assuntos
Indutores da Angiogênese/farmacologia , Barreira Hematoencefálica/efeitos dos fármacos , Lesões Encefálicas Traumáticas/tratamento farmacológico , Células Endoteliais/efeitos dos fármacos , Fatores de Crescimento de Fibroblastos/farmacologia , Pressão Intracraniana , Neovascularização Fisiológica/efeitos dos fármacos , Via de Sinalização Wnt/efeitos dos fármacos , Animais , Comportamento Animal/efeitos dos fármacos , Barreira Hematoencefálica/metabolismo , Barreira Hematoencefálica/patologia , Barreira Hematoencefálica/fisiopatologia , Edema Encefálico/tratamento farmacológico , Edema Encefálico/metabolismo , Edema Encefálico/patologia , Edema Encefálico/fisiopatologia , Lesões Encefálicas Traumáticas/metabolismo , Lesões Encefálicas Traumáticas/patologia , Lesões Encefálicas Traumáticas/fisiopatologia , Permeabilidade Capilar/efeitos dos fármacos , Movimento Celular/efeitos dos fármacos , Células Cultivadas , Modelos Animais de Doenças , Células Endoteliais/metabolismo , Células Endoteliais/patologia , Humanos , Masculino , Memória/efeitos dos fármacos , Camundongos Endogâmicos C57BL , Teste do Labirinto Aquático de Morris/efeitos dos fármacos , Atividade Motora/efeitos dos fármacos , Proteínas Recombinantes/farmacologia , Teste de Desempenho do Rota-Rod , Proteínas de Junções Íntimas/metabolismo , Junções Íntimas/efeitos dos fármacos , Junções Íntimas/metabolismo , Junções Íntimas/patologia
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