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1.
Revista Digital de Postgrado ; 13(1): 389, abr. 2024. ilus
Article in Spanish | LILACS, LIVECS | ID: biblio-1554970

ABSTRACT

Las infecciones del sistema nervioso central son potencialmente mortales, causadas por patógenos, como bacterias, virus y hongos. Para llegar hasta el cerebro, los microorganismos utilizan diversas vías y formas. Este patogeno es una bacteria grampositiva corta, flagelar e intracelular, con la capacidad de inducir su internalización en células fagocíticas (monocitos/macrófagos) y no fagocíticas (células endoteliales). Al infectar los macrófagos, estos microorganismos se valen de su capacidad de fijación, adhesión y migración transendotelial, para cruzar la barrera hematoencefálica, finalmente, generando meningitis bacteriana. En esta revisión describimos el mecanismo de caballo de Troya usado por Listeria monocytogenespara invadir el cerebro en el desarrollo de enfermedades infecciosas e incorporamos nuevos conocimientos sobre moléculas que intervienen en dicho mecanismo(AU)


Central nervous system infections are life-threatening, caused by pathogens such as bacteria, viruses and fungi. To access the brain, microorganisms use various mechanisms. Listeria monocytogenes is a short, flagellar and intracellular gram-positive bacterium, with the ability to induce its internalization in phagocytic (monocytes/macrophages) and non-phagocytic (endothelial cells) cells. By infecting macrophages, these microorganisms take advantage of their binding, adhesion, and transendothelial migrationcapacity to cross the blood-brain barrier, finally generating bacterial meningitis. In this review we describe the Trojan horse mechanism used by Listeria monocytogenesto invade the brain in the development of infectious diseases and we incorporate new knowledge about molecules that intervene in this mechanism(AU)


Subject(s)
Blood-Brain Barrier , Central Nervous System , Meningitis, Bacterial , Listeria monocytogenes , Encephalitis, Viral
2.
Rio de Janeiro; s.n; 2024. 192 p. ilus, tab.
Thesis in Portuguese | LILACS | ID: biblio-1578097

ABSTRACT

A família dos receptores de cininas compreende dois subtipos, sendo o B1R aquele em tem como um de seus agonistas fisiológicos a des-Arg9 -BK (DBK). O receptor B1 tem baixa expressão ou está até mesmo ausente em condições fisiológicas normais, podendo ser induzido por vários estímulos, como o promovido pelo lipopolissacarídeo (LPS), um dos ligantes do receptor do tipo toll 4 (TLR4). Dados presentes na literatura sugerem uma possível interação entre B1R e TLR4, podendo esta ser importante para a resposta inflamatória local. O objetivo deste estudo é ampliar o conhecimento sobre uma possível relação entre esses receptores e a implicação clínica desta na abertura transitória da barreira hematoencefálica (BHE) através da administração de DBK. Em eletrofisiologia de aortas torácicas de camundongos C57BL/6 WT e nocautes para B1R ou TLR4 observamos que a ausência de B1R modifica a resposta de TLR4 e vice-versa nas células endoteliais (alteração da interação de canais de K na via), que na ausência de B1R a DBK ativa o receptor B2 de cininas e que essas vias não são dependentes de óxido nítrico. Imunohistoquímica em aortas de WT indicam que a marcação de TLR4 diminui em todas as camadas celulares quando o anel de aorta é incubado com DBK e LPS, enquanto que a marcação para B1R aumenta signitivamente na camada endotelial. Análises de células endoteliais em cultura (linhagem HBMEC) mostram que os receptores apresentam marcação perinuclear, e até mesmo no interior do núcleo, quando as células são tratadas com DBK e LPS e, quando o tratamento é somente com DBK, há o aumento de pontos de proximidade de B1R e TLR4. Fatores secretados por células de glioblastoma (U87MG e T98G) também alteram o padrão de marcação desses receptores e a resposta aos seus agonistas. Experimentos in vivo, em camundongos suíços inoculados ou não com células da linhagem C6, tratados ou não com DBK, mostram que há a abertura transitória da BHE, aumentando a biodisponibilidade de fármaco (doxorrubicina) no parênquima cerebral e na massa tumoral de glioblastoma. Os dados reforçam a evidência de uma conexão entre a sinalização B1R e TLR4, um alvo terapêutico a ser explorado, além de apresentar evidências adicionais para o uso do agonista fisiológico de B1R para a abertura transitória de BHE, pelo período menor que 48h, o que aumentaria a biodisponibilidade de fármacos no parênquima cerebral.(AU)


The family of ykinin receptors includes two subtypes, with B1R having des-Arg9 -BK (DBK) as one of its physiological agonists. The B1 receptor is either minimally expressed or entirely absent under normal physiological conditions, but can be induced by various stimuli, such as lipopolysaccharide (LPS), a ligand of toll-like receptor 4 (TLR4). Literature suggests a potential interaction between B1R and TLR4, which could be crucial for the local inflammatory response. This study aims to enhance our understanding of the possible relationship between these receptors and its clinical implications for the transient opening of the blood-brain barrier (BBB) through the administration of DBK.Ectrophysiology experiments in thoracic aortas, from C57BL/6 WT mice and B1R or TLR4 knockout mice, we observed that the absence of B1R alters the TLR4 response and vice versa in endothelial cells (affecting the interaction of K channels in the pathway). Additionally, in the absence of B1R, DBK activates the B2 bradykinin receptor, and these pathways are independent of nitric oxide. Immunohistochemistry of WT aortas indicates that TLR4 staining decreases across all cell layers when the aorta ring is incubated with DBK and LPS, while B1R staining significantly increases in the endothelial layer. Endothelial cell cultures (HBMEC) show perinuclear and even intranuclear receptor staining when treated with DBK and LPS, and treatment with DBK increases the proximity points of B1R and TLR4. Factors secreted by glioblastoma cells (U87MG and T98G) also alter the staining pattern of these receptors and their response to agonists. Experiments on Swiss mice, inoculated or not with C6 cell lines and treated or not with DBK, demonstrate that the BBB transiently opens, increasing the bioavailability of the drug (doxorubicin) in the brain parenchyma and glioblastoma tumor mass. These data reinforce evidence of a connection between B1R and TLR4 signaling, a therapeutic target to be explored, and provide additional evidence for the use of the physiological B1R agonists for transient BBB opening for less than 48h, which would increase drug bioavailability in the brain parenchyma.(AU)


Subject(s)
Animals , Mice , Aorta, Thoracic , Blood-Brain Barrier , Receptors, Bradykinin , Glioblastoma/prevention & control , Glioblastoma/drug therapy , Receptors, Cell Surface , Models, Animal , Endothelial Cells , Electrophysiology , Toll-Like Receptor 4
3.
Article in Chinese | WPRIM | ID: wpr-971532

ABSTRACT

OBJECTIVE@#To explore the mechanism that mediates the effect of soybean isoflavones (SI) against cerebral ischemia/reperfusion (I/R) injury in light of the regulation of regional cerebral blood flow (rCBF), ferroptosis, inflammatory response and blood-brain barrier (BBB) permeability.@*METHODS@#A total of 120 male SD rats were equally randomized into sham-operated group (Sham group), cerebral I/R injury group and SI pretreatment group (SI group). Focal cerebral I/R injury was induced in the latter two groups using a modified monofilament occlusion technique, and the intraoperative changes of real-time cerebral cortex blood flow were monitored using a laser Doppler flowmeter (LDF). The postoperative changes of cerebral pathological morphology and the ultrastructure of the neurons and the BBB were observed with optical and transmission electron microscopy. The neurological deficits of the rats was assessed, and the severities of cerebral infarction, brain edema and BBB disruption were quantified. The contents of Fe2+, GSH, MDA and MPO in the ischemic penumbra were determined with spectrophotometric tests. Serum levels of TNF-α and IL-1βwere analyzed using ELISA, and the expressions of GPX4, MMP-9 and occludin around the lesion were detected with Western blotting and immunohistochemistry.@*RESULTS@#The rCBF was sharply reduced in the rats in I/R group and SI group after successful insertion of the monofilament. Compared with those in Sham group, the rats in I/R group showed significantly increased neurological deficit scores, cerebral infarction volume, brain water content and Evans blue permeability (P < 0.01), decreased Fe2+ level, increased MDA level, decreased GSH content and GPX4 expression (P < 0.01), increased MPO content and serum levels of TNF-α and IL-1β (P < 0.01), increased MMP-9 expression and lowered occludin expression (P < 0.01). All these changes were significantly ameliorated in rats pretreated with IS prior to I/R injury (P < 0.05 or 0.01).@*CONCLUSION@#SI preconditioning reduces cerebral I/R injury in rats possibly by improving rCBF, inhibiting ferroptosis and inflammatory response and protecting the BBB.


Subject(s)
Rats , Male , Animals , Rats, Sprague-Dawley , Matrix Metalloproteinase 9/metabolism , Glycine max/metabolism , Occludin/metabolism , Tumor Necrosis Factor-alpha/metabolism , Ferroptosis , Blood-Brain Barrier/ultrastructure , Brain Ischemia/metabolism , Cerebral Infarction , Reperfusion Injury/metabolism , Isoflavones/therapeutic use , Infarction, Middle Cerebral Artery
4.
Neuroscience Bulletin ; (6): 503-518, 2023.
Article in English | WPRIM | ID: wpr-971573

ABSTRACT

The concept of the glial-vascular unit (GVU) was raised recently to emphasize the close associations between brain cells and cerebral vessels, and their coordinated reactions to diverse neurological insults from a "glio-centric" view. GVU is a multicellular structure composed of glial cells, perivascular cells, and perivascular space. Each component is closely linked, collectively forming the GVU. The central roles of glial and perivascular cells and their multi-level interconnections in the GVU under normal conditions and in central nervous system (CNS) disorders have not been elucidated in detail. Here, we comprehensively review the intensive interactions between glial cells and perivascular cells in the niche of perivascular space, which take part in the modulation of cerebral blood flow and angiogenesis, formation of the blood-brain barrier, and clearance of neurotoxic wastes. Next, we discuss dysfunctions of the GVU in various neurological diseases, including ischemic stroke, spinal cord injury, Alzheimer's disease, and major depression disorder. In addition, we highlight the possible therapies targeting the GVU, which may have potential clinical applications.


Subject(s)
Humans , Neuroglia , Nervous System Diseases , Blood-Brain Barrier , Alzheimer Disease , Glymphatic System
5.
Article in English | WPRIM | ID: wpr-971667

ABSTRACT

Stigmasterol is a plant sterol with anti-apoptotic, anti-oxidative and anti-inflammatory effect through multiple mechanisms. In this study, we further assessed whether it exerts protective effect on human brain microvessel endothelial cells (HBMECs) against ischemia-reperfusion injury and explored the underlying mechanisms. HBMECs were used to establish an in vitro oxygen and glucose deprivation/reperfusion (OGD/R) model, while a middle cerebral artery occlusion (MCAO) model of rats were constructed. The interaction between stigmasterol and EPHA2 was detected by surface plasmon resonance (SPR) and cellular thermal shift assay (CETSA). The results showed that 10 μmol·L-1 stigmasterol significantly protected cell viability, alleviated the loss of tight junction proteins and attenuated the blood-brain barrier (BBB) damage induced by OGD/R in thein vitro model. Subsequent molecular docking showed that stigmasterol might interact with EPHA2 at multiple sites, including T692, a critical gatekeep residue of this receptor. Exogenous ephrin-A1 (an EPHA2 ligand) exacerbated OGD/R-induced EPHA2 phosphorylation at S897, facilitated ZO-1/claudin-5 loss, and promoted BBB leakage in vitro, which were significantly attenuated after stigmasterol treatment. The rat MCAO model confirmed these protective effects in vivo. In summary, these findings suggest that stigmasterol protects HBMECs against ischemia-reperfusion injury by maintaining cell viability, reducing the loss of tight junction proteins, and attenuating the BBB damage. These protective effects are at least meditated by its interaction with EPHA2 and inhibitory effect on EPHA2 phosphorylation.


Subject(s)
Humans , Animals , Rats , Stigmasterol , Phosphorylation , Endothelial Cells , Molecular Docking Simulation , Reperfusion Injury , Blood-Brain Barrier , Glucose , Microvessels , Oxygen
6.
Chin. med. j ; Chin. med. j;(24): 780-787, 2023.
Article in English | WPRIM | ID: wpr-980829

ABSTRACT

Magnetic resonance-guided focused ultrasound (MRgFUS) is a novel and minimally invasive technology. Since the US Food and Drug Administration approved unilateral ventral intermediate nucleus-MRgFUS for medication-refractory essential tremor in 2016, studies on new indications, such as Parkinson's disease (PD), psychiatric diseases, and brain tumors, have been on the rise, and MRgFUS has become a promising method to treat such neurological diseases. Currently, as the second most common degenerative disease, PD is a research hotspot in the field of MRgFUS. The actions of MRgFUS on the brain range from thermoablation, blood-brain barrier (BBB) opening, to neuromodulation. Intensity is a key determinant of ultrasound actions. Generally, high intensity can be used to precisely thermoablate brain targets, whereas low intensity can be used as molecular therapies to modulate neuronal activity and open the BBB in conjunction with injected microbubbles. Here, we aimed to summarize advances in the application of MRgFUS for the treatment of PD, with a focus on thermal ablation, BBB opening, and neuromodulation, in the hope of informing clinicians of current applications.


Subject(s)
Humans , Parkinson Disease/therapy , Brain , Blood-Brain Barrier , Essential Tremor/surgery , Brain Neoplasms , Magnetic Resonance Imaging/methods , Magnetic Resonance Spectroscopy
7.
Article in English | WPRIM | ID: wpr-971594

ABSTRACT

Bacteremia induced by periodontal infection is an important factor for periodontitis to threaten general health. P. gingivalis DNA/virulence factors have been found in the brain tissues from patients with Alzheimer's disease (AD). The blood-brain barrier (BBB) is essential for keeping toxic substances from entering brain tissues. However, the effect of P. gingivalis bacteremia on BBB permeability and its underlying mechanism remains unclear. In the present study, rats were injected by tail vein with P. gingivalis three times a week for eight weeks to induce bacteremia. An in vitro BBB model infected with P. gingivalis was also established. We found that the infiltration of Evans blue dye and Albumin protein deposition in the rat brain tissues were increased in the rat brain tissues with P. gingivalis bacteremia and P. gingivalis could pass through the in vitro BBB model. Caveolae were detected after P. gingivalis infection in BMECs both in vivo and in vitro. Caveolin-1 (Cav-1) expression was enhanced after P. gingivalis infection. Downregulation of Cav-1 rescued P. gingivalis-enhanced BMECs permeability. We further found P. gingivalis-gingipain could be colocalized with Cav-1 and the strong hydrogen bonding between Cav-1 and arg-specific-gingipain (RgpA) were detected. Moreover, P. gingivalis significantly inhibited the major facilitator superfamily domain containing 2a (Mfsd2a) expression. Mfsd2a overexpression reversed P. gingivalis-increased BMECs permeability and Cav-1 expression. These results revealed that Mfsd2a/Cav-1 mediated transcytosis is a key pathway governing BBB BMECs permeability induced by P. gingivalis, which may contribute to P. gingivalis/virulence factors entrance and the subsequent neurological impairments.


Subject(s)
Animals , Rats , Bacteremia/metabolism , Blood-Brain Barrier/microbiology , Caveolin 1/metabolism , Gingipain Cysteine Endopeptidases/metabolism , Permeability , Porphyromonas gingivalis/pathogenicity , Transcytosis , Virulence Factors/metabolism
8.
Sheng Li Xue Bao ; (6): 108-114, 2023.
Article in Chinese | WPRIM | ID: wpr-970111

ABSTRACT

Radiation-induced brain injury is a serious complication after cranio-cerebral radiotherapy, which affects the patient's quality of life and survival. A large number of studies have shown that various mechanisms such as neuronal apoptosis, blood-brain barrier damage, and synaptic dysfunction may be related to radiation-induced brain injury. Acupuncture has an important role in clinical rehabilitation of various brain injuries. As a new type of acupuncture, electroacupuncture has the characteristics of strong control ability, uniform and long-lasting stimulation, and is widely used in clinic. This article reviews the effects and mechanisms of electroacupuncture on radiation-induced brain injury, in order to provide a theoretical basis and experimental support for reasonable clinical application.


Subject(s)
Humans , Electroacupuncture , Quality of Life , Brain , Brain Injuries , Blood-Brain Barrier
9.
Zhongnan Daxue xuebao. Yixue ban ; (12): 648-662, 2023.
Article in English | WPRIM | ID: wpr-982334

ABSTRACT

OBJECTIVES@#Restoration of blood circulation within "time window" is the principal treating goal for treating acute ischemic stroke. Previous studies revealed that delayed recanalization might cause serious ischemia/reperfusion injury. However, plenty of evidences showed delayed recanalization improved neurological outcomes in acute ischemic stroke. This study aims to explore the role of delayed recanalization on blood-brain barrier (BBB) in the penumbra (surrounding ischemic core) and neurological outcomes after middle cerebral artery occlusion (MCAO).@*METHODS@#Recanalization was performed on the 3rd day after MCAO. BBB disruption was tested by Western blotting, Evans blue dye, and immunofluorescence staining. Infarct volume and neurological outcomes were evaluated on the 7th day after MCAO. The expression of fibroblast growth factor 21 (FGF21), fibroblast growth factor receptor 1 (FGFR1), phosphatidylinositol-3-kinase (PI3K), and serine/threonine kinase (Akt) in the penumbra were observed by immunofluorescence staining and/or Western blotting.@*RESULTS@#The extraversion of Evans blue, IgG, and albumin increased surrounding ischemic core after MCAO, but significantly decreased after recanalization. The expression of Claudin-5, Occludin, and zona occludens 1 (ZO-1) decreased surrounding ischemic core after MCAO, but significantly increased after recanalization. Infarct volume reduced and neurological outcomes improved following recanalization (on the 7th day after MCAO). The expressions of Claudin-5, Occludin, and ZO-1 decreased surrounding ischemic core following MCAO, which were up-regulated corresponding to the increases of FGF21, p-FGFR1, PI3K, and p-Akt after recanalization. Intra-cerebroventricular injection of FGFR1 inhibitor SU5402 down-regulated the expression of PI3K, p-Akt, Occludin, Claudin-5, and ZO-1 in the penumbra, which weakened the beneficial effects of recanalization on neurological outcomes after MCAO.@*CONCLUSIONS@#Delayed recanalization on the 3rd day after MCAO increases endogenous FGF21 in the penumbra and activates FGFR1/PI3K/Akt pathway, which attenuates BBB disruption in the penumbra and improves neurobehavior in MCAO rats.


Subject(s)
Animals , Rats , Blood-Brain Barrier/metabolism , Brain Ischemia , Claudin-5/metabolism , Infarction, Middle Cerebral Artery/metabolism , Ischemic Stroke/metabolism , Occludin/metabolism , Phosphatidylinositol 3-Kinases/metabolism , Proto-Oncogene Proteins c-akt/metabolism , Rats, Sprague-Dawley , Receptor, Fibroblast Growth Factor, Type 1/metabolism , Reperfusion Injury/metabolism
10.
Zhongnan Daxue xuebao. Yixue ban ; (12): 771-781, 2023.
Article in English | WPRIM | ID: wpr-982347

ABSTRACT

Exosomes are a class of extracellular vesicles with a structure of lipid bilayer-membrane. In the central nervous system (CNS), exosomes can be secreted from both neurons and glial cells. Exosomes released into the extracellular matrix can freely cross the blood-brain barrier and function as crucial carriers of cellular communication and substance exchange in the CNS. Exosomes play a key role in the pathological process of mental disorders such as schizophrenia, depression, and bipolar disorder, and they have the potential to be used as a targeted carrier of antipsychotic medications. Exosomes are likely to become a new tool in the future to aid in the early prevention, accurate diagnosis, and effective treatment for people with mental disorders.


Subject(s)
Humans , Exosomes/physiology , Extracellular Vesicles/physiology , Central Nervous System , Mental Disorders , Blood-Brain Barrier
11.
Chin. j. integr. med ; Chin. j. integr. med;(12): 448-458, 2023.
Article in English | WPRIM | ID: wpr-982293

ABSTRACT

OBJECTIVE@#To investigate the molecular mechanisms underlying the beneficial effect of electroacupuncture (EA) in experimental models of Alzheimer's disease (AD) in vivo.@*METHODS@#Senescence-accelerated mouse prone 8 (SAMP8) mice were used as AD models and received EA at Yingxiang (LI 20, bilateral) and Yintang (GV 29) points for 20 days. For certain experiments, SAMP8 mice were injected intravenously with human fibrin (2 mg). The Morris water maze test was used to assess cognitive and memory abilities. The changes of tight junctions of blood-brain barrier (BBB) in mice were observed by transmission electron microscope. The expressions of fibrin, amyloid- β (Aβ), and ionized calcium-binding adapter molecule 1 (IBa-1) in mouse hippocampus (CA1/CA3) were detected by reverse transcription-quantitative polymerase chain reaction (qRT-PCR), Western blot or immunohistochemical staining. The expression of fibrin in mouse plasma was detected by enzyme-linked immunosorbent assay. The expressions of tight junction proteins zonula occludens-1 and claudin-5 in hippocampus were detected by qRT-PCR and immunofluorescence staining. Apoptosis of hippocampal neurons was detected by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling (TUNEL) staining.@*RESULTS@#Fibrin was time-dependently deposited in the hippocampus of SAMP8 mice and this was inhibited by EA treatment (P<0.05 or P<0.01). Furthermore, EA treatment suppressed the accumulation of Aβ in the hippocampus of SAMP8 mice (P<0.01), which was reversed by fibrin injection (P<0.05 or P<0.01). EA improved SAMP8 mice cognitive impairment and BBB permeability (P<0.05 or P<0.01). Moreover, EA decreased reactive oxygen species levels and neuroinflammation in the hippocampus of SAMP8 mice, which was reversed by fibrin injection (P<0.05 or P<0.01). Mechanistically, EA inhibited the promoting effect of fibrin on the high mobility group box protein 1 (HMGB1)/toll-like receptor 4 (TLR4) and receptor for advanced glycation end products (RAGE)/nicotinamide adenine dinucleotide phosphate (NADPH) signaling pathways (P<0.01).@*CONCLUSION@#EA may potentially improve cognitive impairment in AD via inhibition of fibrin/A β deposition and deactivation of the HMGB1/TLR4 and RAGE/NADPH signaling pathways.


Subject(s)
Mice , Humans , Animals , NADP/metabolism , Toll-Like Receptor 4 , HMGB1 Protein/metabolism , Receptor for Advanced Glycation End Products/metabolism , Blood-Brain Barrier/metabolism , Neuroinflammatory Diseases , Electroacupuncture , Alzheimer Disease/therapy , Hippocampus/metabolism , Amyloid beta-Peptides/metabolism
12.
Zhongguo Zhong Yao Za Zhi ; (24): 4060-4071, 2023.
Article in Chinese | WPRIM | ID: wpr-1008601

ABSTRACT

Neurodegenerative diseases are a collective term for a large group of diseases caused by degenerative changes in nerve cells. Aging is the main risk factor for neurodegenerative diseases. The neurovascular unit(NVU) is the smallest functional unit of the brain, which regulates brain blood flow and maintains brain homeostasis. Accelerated aging of NVU cells directly impairs NVU function and leads to the occurrence of various neurodegenerative diseases. The intrinsic mechanisms of NVU cell aging are complex and involve oxidative stress damage, loss of protein homeostasis, DNA damage, mitochondrial dysfunction, immune inflammatory response, and impaired cellular autophagy. In recent years, studies have found that traditional Chinese medicine(TCM) can inhibit NVU aging through multiple pathways and targets, exerting a brain-protective effect. Therefore, this article aimed to provide a theoretical basis for further research on TCM inhibition of NVU cell aging and references for new drug development and clinical applications by reviewing its mechanisms of anti-aging, such as regulating relevant proteins, improving mitochondrial dysfunction, reducing DNA damage, lowering inflammatory response, antioxidant stress, and modulating cellular autophagy.


Subject(s)
Humans , Medicine, Chinese Traditional , Neurodegenerative Diseases/drug therapy , Brain , Aging , Neurons , Blood-Brain Barrier
13.
J. biomed. eng ; Sheng wu yi xue gong cheng xue za zhi;(6): 753-761, 2023.
Article in Chinese | WPRIM | ID: wpr-1008896

ABSTRACT

It is a significant challenge to improve the blood-brain barrier (BBB) permeability of central nervous system (CNS) drugs in their development. Compared with traditional pharmacokinetic property tests, machine learning techniques have been proven to effectively and cost-effectively predict the BBB permeability of CNS drugs. In this study, we introduce a high-performance BBB permeability prediction model named balanced-stacking-learning based BBB permeability predictor(BSL-B3PP). Firstly, we screen out the feature set that has a strong influence on BBB permeability from the perspective of medicinal chemistry background and machine learning respectively, and summarize the BBB positive(BBB+) quantification intervals. Then, a combination of resampling algorithms and stacking learning(SL) algorithm is used for predicting the BBB permeability of CNS drugs. The BSL-B3PP model is constructed based on a large-scale BBB database (B3DB). Experimental validation shows an area under curve (AUC) of 97.8% and a Matthews correlation coefficient (MCC) of 85.5%. This model demonstrates promising BBB permeability prediction capability, particularly for drugs that cannot penetrate the BBB, which helps reduce CNS drug development costs and accelerate the CNS drug development process.


Subject(s)
Blood-Brain Barrier , Algorithms , Area Under Curve , Databases, Factual , Permeability
14.
Rio de Janeiro; s.n; 2023. 80 p. ilus, tab, graf.
Thesis in Portuguese | LILACS | ID: biblio-1584579

ABSTRACT

O consumo de bebidas alcoólicas durante a gestação representa um grande problema de saúde pública. No mundo, cerca de 10% das mulheres relatam o consumo de álcool durante a gestação, evento que pode promover o estabelecimento dos transtornos do espectro alcoólico fetal (TEAF), sendo a síndrome alcoólica fetal (SAF), a forma mais grave, sendo caracterizada por alterações craniofaciais, restrição do crescimento corporal e alterações no desenvolvimento do Sistema Nervoso Central (SNC), sendo este último um dos principais alvos dos efeitos teratogênicos do álcool. O correto funcionamento do SNC depende da correta formação de células neurais, como os astrócitos, os quais interagem com células endoteliais vasculares, estabelecendo assim a unidade básica da barreira hematoencefálica (BHE), entretanto, pouco se sabe sobre como o etanol afeta esses eventos durante o desenvolvimento. Neste trabalho, tivemos como objetivos, coletar dados sobre a perfil de consumo de álcool durante a gestação em gestantes admitidas no Núcleo Perinatal do Hospital Pedro Ernesto (HUPE) da Universidade do Estado do Rio de Janeiro (UERJ), coletar amostras de sangue de cordão umbilical de recém nascidos, cujas mães reportaram o consumo de álcool durante a gestação, realizar ensaios proteômicos a partir do soro do sangue de cordão, e avaliar os efeitos das proteínas séricas na função de células endoteliais da BHE in vitro. Através da entrevista com as pacientes, 27% reportaram o uso de álcool em qualquer período da gestação, sendo a maioria, no primeiro trimestre. Destas, a maioria (55%) na faixa etária dos 33-43 anos de idade. Os recém-nascidos tanto das gestantes controles quanto aquelas que reportaram o uso de álcool, não apresentaram diferenças quanto ao peso e comprimento ao nascimento. Após a coleta do sangue do cordão umbilical, isolamos o soro para tratar culturas de células endoteliais de microcapilares cerebrais humanos (HBMEC). Culturas de HBMECs tratadas com soro de pacientes expostos ao etanol (S-etanol) apresentaram uma redução de 68% nos níveis de proteínas de junção ocludentes ZO-1 e de 38% nos do transportador de glicose tipo 1 (GLUT-1), em comparação às expostas ao soro de pacientes controle (S-controle). Estes eventos foram acompanhados pela perda de função de barreira com aumento da permeabilidade da monocamada endotelial, e redução da capacidade migratória destas células, quando comparado às expostas ao S-controle. A análise do perfil de proteínas relacionadas a angiogênese no meio condicionado de HBMECs , revelou alteração nos níveis destas em células tratadas com S-etanol. A análise proteômica dos soros revelou um total de 392 proteínas, com um perfil específico de proteínas exclusivamente presentes em amostras S-controle (30) ou S-etanol (10), sendo que 12, presentes em ambas as amostras, tiveram seus níveis alterados em amostras S-etanol em comparação à S-Controle. O acompanhamento das crianças após o 1 ano de vida, revelou algumas diferenças de desenvolvimento. Nossos resultados apontam a exposição ao etanol durante a gestação alcançou um número relativamente alto de gestantes especialmente durante o 1º trimestre da gestação, e que isto pode ter contribuído para alterar o perfil de proteínas presentes no soro de sangue de cordão umbilical, podendo desencadear disfunções na função e estrutura de células da BHE no cérebro em desenvolvimento e no desenvolvimento pós-natal em crianças expostas.(AU)


The consumption of alcoholic beverages during pregnancy represents a major public health problem. In the world, around 10% of women report drinking alcohol during pregnancy, an event that can promote the establishment of fetal alcohol spectrum disorders (FASD), with fetal alcohol syndrome (FAS) being the most severe form, characterized by craniofacial changes, restriction of body growth and changes in the development of the central nervous system (CNS), the latter being one of the main targets of the teratogenic effects of alcohol (ethanol). The correct functioning of the CNS depends on the correct formation of neural cells, such as astrocytes, which interact with vascular endothelial cells, thus establishing the blood-brain barrier (BBB). However, little is known about how ethanol affects these events during the development. In this work, we aimed to collect data regarding the prevalence of alcohol consumption during pregnancy in pregnant women admitted to the Perinatal Center of the Pedro Ernesto Hospital (HUPE) of the State University of Rio de Janeiro (UERJ), collect umbilical cord blood samples, whose mothers reported alcohol consumption during pregnancy, perform proteomic assays using cord blood serum, and evaluate the effects of serum proteins on the function of BBB endothelial cells in vitro. Through interviews with patients, 27% reported using alcohol at any time during pregnancy, mostly in the first trimester. Of these, the majority (55%) are in the 33-43 year old age group. The newborns of both control pregnant women and those who reported alcohol use showed no differences in weight, length at birth. After collecting umbilical cord blood, we isolated serum to treat human brain microcapillary endothelial cell (HBMEC) cultures. Cultures of HBMECs treated with serum from patients exposed to ethanol (S-ethanol) showed a 68% reduction in the levels of tight junction proteins ZO-1 and a 38% reduction in glucose transporter type 1 (GLUT-1), in comparison to those exposed to serum from control patients (S-control). These events were accompanied by the loss of barrier function with increased permeability of the endothelial monolayer, and reduced migratory capacity of these cells, when compared to those exposed to the S-control. Analysis of angiogenesis related proteins profile of conditioned medium from HBMECs revealed changes in the levels of these proteins in cells treated with S-ethanol. The proteomic analysis of the sera revealed a total of 392 proteins, with a specific profile of proteins exclusively present in S-control (30) or S-ethanol (10) samples, with 12, present in both samples, presenting their levels altered in S-ethanol samples compared to S-Control. Follow up of children's development 1 year after birth, revealed differences in development. Our results indicate that exposure to ethanol during pregnancy reached a relatively high number of pregnant women, especially during the 1st trimester of pregnancy, and that this may have contributed to altering the profile of proteins present in umbilical cord blood serum, which could trigger dysfunctions in the function and structure of BBB cells in the developing brain and postnatal development in exposed children.(AU)


Subject(s)
Female , Pregnancy , Infant, Newborn , Infant , Alcohol Drinking , Alcohol Drinking/epidemiology , Blood-Brain Barrier , Central Nervous System/growth & development , Proteomics , Pregnant Women , Endothelial Cells , Ethanol , Fetal Alcohol Spectrum Disorders , Fetal Blood , Angiogenesis
15.
Zhongguo Zhong Yao Za Zhi ; (24): 2028-2037, 2022.
Article in Chinese | WPRIM | ID: wpr-928142

ABSTRACT

Precious Tibetan medicine formula is a characteristic type of medicine commonly used in the clinical treatment of central nervous system diseases. Through the summary of modern research on the precious Tibetan medicine formulas such as Ratnasampil, Ershiwuwei Zhenzhu Pills, Ershiwewei Shanhu Pills, and Ruyi Zhenbao Pills, it is found that they have obvious advantages in the treatment of stroke, Alzheimer's disease, epilepsy, angioneurotic headache, and vascular dementia. Modern pharmacological studies have shown that the mechanisms of precious Tibetan medicine formulas in improving central nervous system diseases are that they promote microcirculation of brain tissue, regulate the permeability of the blood-brain barrier, alleviate inflammation, relieve oxidative stress damage, and inhibit nerve cell apoptosis. This review summarizes the clinical and pharmacological studies on precious Tibetan medicine formulas in prevention and treatment of central nervous system diseases, aiming to provide a reference for future in-depth research and innovative discovery of Tibetan medicine against central nervous diseases.


Subject(s)
Humans , Blood-Brain Barrier , Brain , Central Nervous System Diseases , Medicine, Tibetan Traditional , Stroke/drug therapy
16.
Arq. neuropsiquiatr ; Arq. neuropsiquiatr;79(1): 56-67, Jan. 2021. tab, graf
Article in English | LILACS | ID: biblio-1153137

ABSTRACT

ABSTRACT Background: Increased concentrations of serum proteins in cerebrospinal fluid (CSF) are interpreted as blood-CSF barrier dysfunction. Frequently used interpretations such as barrier leakage, disruption or breakdown contradict CSF protein data, which suggest a reduced CSF flow rate as the cause. Results: Even the severest barrier dysfunctions do not change the molecular size-dependent selectivity or the interindividual variation of the protein transfer across barriers. Serum protein concentrations in lumbar CSF increase with hyperbolic functions, but the levels of proteins that do not pass the barrier remain constant (brain proteins) or increase linearly (leptomeningal proteins). All CSF protein dynamics above and below a lumbar blockade can also be explained, independent of their barrier passage, by a reduced caudally directed flow. Local accumulation of gadolinium in multiple sclerosis (MS) is now understood as due to reduced bulk flow elimination by interstitial fluid (ISF). Nonlinear change of the steady state in barrier dysfunction and along normal rostro-caudal gradients supports the diffusion/flow model and contradicts obstructions of diffusion pathways. Regardless of the cause of the disease, pathophysiological flow blockages are found in bacterial meningitis, leukemia, meningeal carcinomatosis, Guillain-Barré syndrome, MS and experimental allergic encephalomyelitis. In humans, the fortyfold higher albumin concentrations in early fetal development decrease later with maturation of the arachnoid villi, i.e., with beginning CSF outflow, which contradicts a relevant outflow to the lymphatic system. Respiration- and heartbeat-dependent oscillations do not disturb net direction of CSF flow. Conclusion: Blood-CSF and blood-brain barrier dysfunctions are an expression of reduced CSF or ISF flow rate.


RESUMO Introdução: Concentrações aumentadas de proteínas séricas no líquido cefalorraquidiano são interpretadas como disfunção da barreira (hemato-liquórica) sanguínea do LCR. Interpretações frequentemente usadas, como vazamento de barreira (quebra ou rompimento de barreira), rompimento ou quebra, contradiz os dados de proteína do LCR, que sugerem uma taxa de fluxo reduzida do LCR como a causa. Resultados: Mesmo as disfunções de barreira mais graves não alteram a seletividade dependente do tamanho molecular nem a variação interindividual da transferência de proteína através de barreiras. As concentrações de proteínas séricas no LCR lombar aumentam com as funções hiperbólicas, mas as proteínas que não passam a barreira permanecem constantes (proteínas do cérebro) ou aumentam linearmente (proteínas leptomeningeais). Toda a dinâmica das proteínas do LCR acima e abaixo de um bloqueio lombar também pode ser explicada, independente de sua passagem pela barreira, por um fluxo caudal reduzido. O acúmulo local de gadolínio na esclerose múltipla (EM) é agora entendido como decorrente da redução da eliminação do bulk flow pelo fluido intersticial (FIS). A mudança não linear do estado estacionário na disfunção da barreira e ao longo dos gradientes rostro-caudais normais apoia o modelo de difusão/fluxo e contradiz as obstruções das vias de difusão. Independentemente da causa da doença, os bloqueios fisiopatológicos do fluxo são encontrados na meningite bacteriana, leucemia, carcinomatose meníngea, síndrome de Guillain-Barré, EM e encefalomielite alérgica experimental. Em humanos, as concentrações de albumina quarenta vezes mais altas no desenvolvimento fetal inicial diminuem tarde com a maturação das vilosidades aracnoides, isto é, com o início do fluxo de LCR, o que contradiz um fluxo relevante para o sistema linfático. As oscilações dependentes da respiração e do batimento cardíaco não perturbam a direção do fluxo do LCR. Conclusão: As disfunções das barreiras hemato-liquórica e hemato-encefálica são uma expressão da redução da taxa de fluxo do LCR ou FIS.


Subject(s)
Humans , Brain/metabolism , Blood-Brain Barrier/metabolism , Blood Proteins/metabolism , Cerebrospinal Fluid/metabolism
17.
Article in English | WPRIM | ID: wpr-922254

ABSTRACT

To investigate the effects of on behavior and blood brain barrier (BBB) in Alzheimer's disease mice. Thirty-eight 4-month-old APP/PS1 double transgenic mice were randomly divided into three groups: model group, low-dose group and high-dose group. Saline, and 12 g·kg·d were given to each group by continuous gavage once a day for respectively. The changes in activities of daily live and fear conditioning memory behavior of mice were examined by nesting behavior test and fear conditioning test, respectively. The β-amyloid protein (Aβ) depositions in cortex and hippocampal CA1 area of mice were detected by thioflavin T staining. The CD34 and activities fibrinogen (Fib) immunofluorescence double staining were used to determine the vascular endothelial integrity and BBB exudation. Compared with model mice, activities of daily live were significantly improved in low-dose and high-dose groups (both <0.01), the fear memory ability was significantly increased in high-dose group (<0.01). The amount of Aβ deposition in cortex and hippocampal CA1 decreased significantly in high-dose group, the area ratio decreased significantly; the area ratio of Aβ deposition in hippocampal CA1 region in low-dose group also decreased (all <0.05). The proportions of CD34 positive area of cortex in low and high dose groups increased, the percentage of fibrinogen positive area decreased (all <0.05). The proportion of CD34 positive area in hippocampal CA1 region in high-dose group was significantly increased, the percentage of fibrinogen positive area decreased significantly (both <0.05). especially high-dose can improve the activities of daily live and fear conditioning memory function of APP/PS1 mice, reduce the deposition of Aβ in brain. The mechanism may be related to the reduction of BBB permeability and the protection of the integrity of BBB.


Subject(s)
Animals , Mice , Alzheimer Disease , Amyloid beta-Protein Precursor , Blood-Brain Barrier/metabolism , Disease Models, Animal , Hippocampus/metabolism , Mice, Inbred C57BL , Mice, Transgenic
18.
Rev. cuba. invest. bioméd ; 40(supl.1): e1584, 2021. tab, graf
Article in English | LILACS, CUMED | ID: biblio-1289475

ABSTRACT

Introduction: MASP-2 is a mannose blinding lectin associate to serine protease in cerebrospinal fluid and its dynamics through the blood brain barrier is unknown. Objective: To describe MASP-2 diffusion pattern from blood to cerebrospinal fluid. Methods: A transversal observational prospective study was performed 56 control samples of cerebrospinal fluid and serum were employed. ELISA measured MASP-2. Two groups were made: control patients without organic brain disease with normal cerebrospinal fluid and normal barrier function and patients without inflammatory diseases with a blood cerebrospinal fluid barrier dysfunction. Results: MASP-2 concentration in cerebrospinal fluid increase with augment the Q Albumin. QMASP-2 vs. Q Albumin saturation curve indicates that MASP-2 is interacting with other molecules in the subarachnoid environment. The higher inter-individual variation of cerebrospinal fluid MASP-2 of the control compared to the serum MASP-2 indicates that MASP-2 is a protein derived from blood. Conclusions: MASP-2 in CSF is predominantly blood-derived. The saturation curve demonstrates that MASP-2 interacts with the starters of the lectin pathway like mannose binding lectin, ficolins and collectin LK(AU)


Introducción: MASP2 es una proteína de unión a manosa asociada a una proteasa de serina encontrada en la periferia, pero puede pasar a líquido cefalorraquídeo. Sin embargo, su dinámica a través de la barrera sangre-líquido cefalorraquídeo es aún desconocida. Objetivo: Describir la difusión del MASP-2 desde la sangre al líquido cefalorraquídeo. Métodos: Se realiza estudio observacional prospectivo de corte transversal donde se emplearon 56 muestras de suero y líquido cefalorraquídeo. Fue seleccionado un grupo control con pacientes sin enfermedad orgánica del cerebro, con líquido cefalorraquídeo y función de barrera normal y otro grupo de pacientes sin enfermedades inflamatorias del cerebro con disfunción de barrera sangre-líquido cefalorraquídeo. Resultados: La concentración de MASP-2 en líquido cefalorraquídeo aumentó con el incremento de la Q Albúmina. La curva de saturación de Q MASP-2 contra la Q Albúmina indicó que el MASP-2 se encuentra interactuando con otras moléculas en el espacio subaracnoideo. El aumento del coeficiente de variación individual de MASP-2 en líquido cefalorraquídeo de los controles comparado con el MASP-2 en suero indicó que el MASP-2 es una proteína derivada de la sangre. Conclusiones: La producción de MASP-2 en líquido cefalorraquídeo es predominantemente derivada de la sangre. La curva de saturación demostró que el MASP-2 interactúa con los iniciadores de la vía de las lectinas como lectina unida a manosa, las ficolinas y la colectina LK(AU)


Subject(s)
Humans , Enzyme-Linked Immunosorbent Assay , Blood-Brain Barrier , Cerebrospinal Fluid/physiology , Mannose-Binding Protein-Associated Serine Proteases , Mannose , Cross-Sectional Studies , Prospective Studies
19.
Article in Chinese | WPRIM | ID: wpr-828924

ABSTRACT

OBJECTIVE@#To investigate the effects of blocking the activation of ERK pathway on the expression of matrix metalloproteinase-9 (MMP-9) and the formation of cerebral edema in SD rats after brain injury.@*METHODS@#Ninety SD rats were randomly divided into 3 equal groups, including a sham-operated group, modified Feeney's traumatic brain injury model group, and ERK inhibition group where the ERK inhibitor SCH772984 (500 μg/kg) was injected via the femoral vein 15 min before brain trauma. At 2 h and 2 days after brain trauma, the permeability of blood-brain barrier was assessed by Evans blue method, the water content of the brain tissue was determined, and the phosphorylation level of ERK and the expression level of MMP-9 mRNA and protein were measured by RT-PCR and Western blotting.@*RESULTS@#Compared with the sham-operated group, the rats with brain trauma exhibited significantly increased level of ERK phosphorylation at 2 h and significantly increased expression of MMP-9 mRNA and protein 2 days after the injury ( < 0.01). Treatment with the ERK inhibitor significantly decreased the phosphorylation level of ERK after the injury ( < 0.01), suppressed over-expression of MMP-9 mRNA and protein 2 days after the injury ( < 0.01). The permeability of blood-brain barrier increased significantly 2 h after brain trauma ( < 0.05) and increased further at 2 days ( < 0.01); the water content of the brain did not change significantly at 2 h ( > 0.05) but increased significantly 2 d after the injury ( < 0.01). Treatment with the ERK inhibitor significantly lowered the permeability of blood-brain barrier and brain water content after brain trauma ( < 0.01).@*CONCLUSIONS@#Blocking the activation of ERK pathway significantly reduced the over-expression of MMP-9 and alleviates the damage of blood-brain barrier and traumatic brain edema, suggesting that ERK signaling pathway plays an important role in traumatic brain edema by regulating the expression of MMP-9.


Subject(s)
Animals , Rats , Blood-Brain Barrier , Brain Edema , Brain Injuries, Traumatic , MAP Kinase Signaling System , Matrix Metalloproteinase 9 , Rats, Sprague-Dawley
20.
Zhongguo Zhong Yao Za Zhi ; (24): 2924-2931, 2020.
Article in Chinese | WPRIM | ID: wpr-828066

ABSTRACT

According to traditional Chinese medicine, "spleen transport" is closely related to the metabolism of substance and energy. Studies have shown that Alzheimer's disease(AD) is a disease related to glucose and lipid metabolism and energy metabolism. The traditional Chinese medicine Jiangpi Recipe can improve the learning ability and memory of AD animal model. Sijunzi Decoction originated from Taiping Huimin Hefang Prescription is the basic prescription for strengthening and nourishing the spleen, with the effects of nourishing Qi and strengthening the spleen. In this experiment, human brain microvascular endothelial cells(HBMEC) and Sijunzi Decoction water extract(0.25, 0.5, 1 mg·L~(-1)) were pre-incubated for 2 h, and then Aβ_(25-35) oligomers(final concentration 40 μmol·L~(-1)) was added for co-culture for 22 hours. The effect of Sijunzi Decoction on the activity of Aβ_(25-35) oligomer injured cells and the expression of related proteins were investigated. Q-TOF-LC-MS was used first for principal component analysis of Sijunzi Decoction water extract. Then MTT assay was used to investigate the effect of Sijunzi Decoction water extract on the proliferation of HBMEC cells. Real-time fluorescence quantitative PCR(RT-qPCR) was employed to detect the mRNA expression of GLUT1, RAGE, and LRP1. The expression of Aβ-related proteins across blood-brain barrier(RAGE, LRP1) was detected by Western blot. The results showed that 40 μmol·L~(-1) Aβ_(25-35) oligomers could induce endothelial cell damage, reduce cell survival, increase expression of RAGE mRNA and RAGE protein, and reduce expression of GLUT1 mRNA, LRP1 mRNA, and LRP1 protein. Sijunzi Decoction water extract could reduce the Aβ_(25-35) oligomer-induced cytotoxicity of HBMEC, decrease the expression of RAGE mRNA and RAGE protein, and increase the expression of GLUT1 mRNA, LRP1 mRNA and LRP1 protein. The results indicated that Sijunzi Decoction could reduce the injury of HBMEC cells induced by Aβ_(25-35) oligomer, and regulate the transport-related proteins GLUT1, RAGE and LRP1, which might be the mechanism of regulating Aβ_(25-35) transport across the blood-brain barrier.


Subject(s)
Animals , Humans , Amyloid beta-Peptides , Blood-Brain Barrier , Drugs, Chinese Herbal , Endothelial Cells
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