scholarly journals Photostimulation of Extravasation of Beta-Amyloid through the Model of Blood-Brain Barrier

Electronics ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 1056
Author(s):  
Ekaterina Zinchenko ◽  
Maria Klimova ◽  
Aysel Mamedova ◽  
Ilana Agranovich ◽  
Inna Blokhina ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Beta Amyloid ◽  
Brain Barrier ◽  
Therapeutic Effects ◽  
Cervical Lymph Nodes ◽  
Blood Brain ◽  
The Central Nervous System ◽  
Vitro Model ◽  
The Brain

Alzheimer’s disease (AD) is an incurable pathology associated with progressive decline in memory and cognition. Phototherapy might be a new promising and alternative strategy for the effective treatment of AD, and has been actively discussed over two decades. However, the mechanisms of therapeutic photostimulation (PS) effects on subjects with AD remain poorly understood. The goal of this study was to determine the mechanisms of therapeutic PS effects in beta-amyloid (Aβ)-injected mice. The neurological severity score and the new object recognition tests demonstrate that PS 9 J/cm2 attenuates the memory and neurological deficit in mice with AD. The immunohistochemical assay revealed a decrease in the level of Aβ in the brain and an increase of Aβ in the deep cervical lymph nodes obtained from mice with AD after PS. Using the in vitro model of the blood-brain barrier (BBB), we show a PS-mediated decrease in transendothelial resistance and in the expression of tight junction proteins as well an increase in the BBB permeability to Aβ. These findings suggest that a PS-mediated BBB opening and the activation of the lymphatic clearance of Aβ from the brain might be a crucial mechanism underlying therapeutic effects of PS in mice with AD. These pioneering data open new strategies in the development of non-pharmacological methods for therapy of AD and contribute to a better understanding of the PS effects on the central nervous system.

scholarly journals Comparative analysis of neuroinvasion by Japanese encephalitis virulent and vaccine viral strains in an in vitro model of human blood-brain barrier

PLoS ONE ◽  
2021 ◽  
Vol 16 (6) ◽  
pp. e0252595
Author(s):  
Cécile Khou ◽  
Marco Aurelio Díaz-Salinas ◽  
Anaelle da Costa ◽  
Christophe Préhaud ◽  
Patricia Jeannin ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Japanese Encephalitis ◽  
In Vitro Model ◽  
Molecular Mechanisms ◽  
Brain Barrier ◽  
Blood Brain ◽  
The Central Nervous System ◽  
Vitro Model ◽  
Viral Determinants

Japanese encephalitis virus (JEV) is the major cause of viral encephalitis in South East Asia. It has been suggested that, as a consequence of the inflammatory process during JEV infection, there is disruption of the blood-brain barrier (BBB) tight junctions that in turn allows the virus access to the central nervous system (CNS). However, what happens at early times of JEV contact with the BBB is poorly understood. In the present work, we evaluated the ability of both a virulent and a vaccine strain of JEV (JEV RP9 and SA14-14-2, respectively) to cross an in vitro human BBB model. Using this system, we demonstrated that both JEV RP9 and SA14-14-2 are able to cross the BBB without disrupting it at early times post viral addition. Furthermore, we find that almost 10 times more RP9 infectious particles than SA14-14 cross the model BBB, indicating this BBB model discriminates between the virulent RP9 and the vaccine SA14-14-2 strains of JEV. Beyond contributing to the understanding of early events in JEV neuroinvasion, we demonstrate this in vitro BBB model can be used as a system to study the viral determinants of JEV neuroinvasiveness and the molecular mechanisms by which this flavivirus crosses the BBB during early times of neuroinvasion.

Epitope-Dependent Effects of Beta-Amyloid Antibodies on Beta-Amyloid Clearance in an In Vitro Model of the Blood-Brain Barrier

2011 ◽  
Vol 18 (5) ◽  
pp. 373-379 ◽  
Author(s):  
CORBIN J. BACHMEIER ◽  
DAVID BEAULIEU-ABDELAHAD ◽  
MICHAEL J. MULLAN ◽  
DANIEL PARIS
Keyword(s):  
Blood Brain Barrier ◽  
In Vitro Model ◽  
Beta Amyloid ◽  
Brain Barrier ◽  
Blood Brain ◽  
Vitro Model

scholarly journals Senescence and associated blood–brain barrier alterations in vitro

2021 ◽  
Author(s):  
Ellaine Salvador ◽  
Malgorzata Burek ◽  
Mario Löhr ◽  
Michiaki Nagai ◽  
Carsten Hagemann ◽  
...  
Keyword(s):  
Blood Brain Barrier ◽  
Intercellular Junctions ◽  
In Vitro Models ◽  
Brain Barrier ◽  
Initial Attempt ◽  
Blood Brain ◽  
The Central Nervous System ◽  
Vitro Model ◽  
The Relationship

AbstractProgressive deterioration of the central nervous system (CNS) is commonly associated with aging. An important component of the neurovasculature is the blood–brain barrier (BBB), majorly made up of endothelial cells joined together by intercellular junctions. The relationship between senescence and changes in the BBB has not yet been thoroughly explored. Moreover, the lack of in vitro models for the study of the mechanisms involved in those changes impede further and more in-depth investigations in the field. For this reason, we herein present an in vitro model of the senescent BBB and an initial attempt to identify senescence-associated alterations within.

scholarly journals Propofol-induced damage to the blood-brain barrier endothelium evinces a vascular endothelial growth factor (VEGF) -dependent mechanism.

2020 ◽  
Vol 3 ◽  
Author(s):  
Dustin Parsons ◽  
Jason Hughes ◽  
Scott Canfield
Keyword(s):  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Vegf Receptor ◽  
Blood Brain ◽  
The Central Nervous System ◽  
Vitro Model ◽  
Induced Pluripotent ◽  
Endothelial Growth Factor ◽  
Dependent Mechanism

Background and Hypothesis:  Propofol is an anesthetic commonly used to induce general anesthesia for a myriad of medical procedures. However, a growing corpus of evidence suggests that propofol-induced increases in VEGF may contribute to blood-brain barrier (BBB) leakiness in varying animal models. The BBB is a neurovascular structure which protects the central nervous system from pathogens, toxins, and other deleterious metabolites; therefore, considerations regarding BBB integrity in humans are indispensable to the practice of anesthesia. We hypothesize that propofol-induced BBB dysfunction in human models is partially mediated by an increase in VEGF expression.    Methods:  We utilized human induced pluripotent stem cells (hiPSC) to derive brain microvascular endothelial cells (BMECs)—the barrier forming cell type of the BBB. BMECs were then subjected to clinically relevant doses of propofol for 3 hours, and barrier integrity was monitored via transendothelial electrical resistance (TEER) and para-cellular permeability for up to 72 hours. Propofol-induced VEGF levels were determined with an ELISA assay. Axitinib, a VEGF receptor blocker, was further utilized to assess the role of VEGF in propofol-induced BBB breakdown.    Results:  Prior works, including this study, have shown that propofol induces BBB damage, as demonstrated by decreases in TEER; here, preliminary work with ELISA assays further suggest that BMECs treated with propofol demonstrate an upregulation of VEGF. Pretreatment of BMECs with Axitinib before the addition of propofol partially rescues TEER and thus attenuates the propofol-mediated diminution of TEER. These observations thereby implicate VEGF as a damage mediator after propofol treatment.    Conclusion and Potential Impact:  This study utilized an in vitro model to demonstrate that propofol may mediate, in part, damage to blood- brain barrier endothelium via a VEGF dependent mechanism; thus, this work may guide future investigations to facilitate the development of safer anesthetic alternatives, or towards additional pharmacologic interventions that counteract propofol-mediated damage during anesthetic induction. 

scholarly journals Cryptococcal Yeast Cells Invade the Central Nervous System via Transcellular Penetration of the Blood-Brain Barrier

2004 ◽  
Vol 72 (9) ◽  
pp. 4985-4995 ◽  
Author(s):  
Yun C. Chang ◽  
Monique F. Stins ◽  
Michael J. McCaffery ◽  
Georgina F. Miller ◽  
Dan R. Pare ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Endothelial Cells ◽  
Nervous System ◽  
Blood Brain Barrier ◽  
Yeast Cells ◽  
Brain Barrier ◽  
Blood Brain ◽  
The Central Nervous System ◽  
The Brain

ABSTRACT Cryptococcal meningoencephalitis develops as a result of hematogenous dissemination of inhaled Cryptococcus neoformans from the lung to the brain. The mechanism(s) by which C. neoformans crosses the blood-brain barrier (BBB) is a key unresolved issue in cryptococcosis. We used both an in vivo mouse model and an in vitro model of the human BBB to investigate the cryptococcal association with and traversal of the BBB. Exposure of human brain microvascular endothelial cells (HBMEC) to C. neoformans triggered the formation of microvillus-like membrane protrusions within 15 to 30 min. Yeast cells of C. neoformans adhered to and were internalized by the HBMEC, and they crossed the HBMEC monolayers via a transcellular pathway without affecting the monolayer integrity. The histopathology of mouse brains obtained after intravenous injection of C. neoformans showed that the yeast cells either were associated with endothelial cells or escaped from the brain capillary vessels into the neuropil by 3 h. C. neoformans was found in the brain parenchyma away from the vessels by 22 h. Association of C. neoformans with the choroid plexus, however, was not detected during up to 10 days of observation. Our findings indicate that C. neoformans cells invade the central nervous system by transcellular crossing of the endothelium of the BBB.

scholarly journals Miniaturization and Automation of a Human In Vitro Blood–Brain Barrier Model for the High-Throughput Screening of Compounds in the Early Stage of Drug Discovery

Pharmaceutics ◽  
2021 ◽  
Vol 13 (6) ◽  
pp. 892
Author(s):  
Elisa L. J. Moya ◽  
Elodie Vandenhaute ◽  
Eleonora Rizzi ◽  
Marie-Christine Boucau ◽  
Johan Hachani ◽  
...  
Keyword(s):  
Drug Discovery ◽  
Blood Brain Barrier ◽  
Early Stage ◽  
Molecular Transport ◽  
Brain Barrier ◽  
Blood Brain ◽  
Cns Drugs ◽  
The Impact ◽  
The Brain

Central nervous system (CNS) diseases are one of the top causes of death worldwide. As there is a difficulty of drug penetration into the brain due to the blood–brain barrier (BBB), many CNS drugs treatments fail in clinical trials. Hence, there is a need to develop effective CNS drugs following strategies for delivery to the brain by better selecting them as early as possible during the drug discovery process. The use of in vitro BBB models has proved useful to evaluate the impact of drugs/compounds toxicity, BBB permeation rates and molecular transport mechanisms within the brain cells in academic research and early-stage drug discovery. However, these studies that require biological material (animal brain or human cells) are time-consuming and involve costly amounts of materials and plastic wastes due to the format of the models. Hence, to adapt to the high yields needed in early-stage drug discoveries for compound screenings, a patented well-established human in vitro BBB model was miniaturized and automated into a 96-well format. This replicate met all the BBB model reliability criteria to get predictive results, allowing a significant reduction in biological materials, waste and a higher screening capacity for being extensively used during early-stage drug discovery studies.

scholarly journals Trojan Horse Transit Contributes to Blood-Brain Barrier Crossing of a Eukaryotic Pathogen

mBio ◽  
2017 ◽  
Vol 8 (1) ◽  
Author(s):  
Felipe H. Santiago-Tirado ◽  
Michael D. Onken ◽  
John A. Cooper ◽  
Robyn S. Klein ◽  
Tamara L. Doering
Keyword(s):  
Experimental Evidence ◽  
Cryptococcus Neoformans ◽  
Blood Brain Barrier ◽  
Fungal Pathogen ◽  
Trojan Horse ◽  
Brain Barrier ◽  
Barrier Crossing ◽  
Blood Brain ◽  
The Brain

ABSTRACT The blood-brain barrier (BBB) protects the central nervous system (CNS) by restricting the passage of molecules and microorganisms. Despite this barrier, however, the fungal pathogen Cryptococcus neoformans invades the brain, causing a meningoencephalitis that is estimated to kill over 600,000 people annually. Cryptococcal infection begins in the lung, and experimental evidence suggests that host phagocytes play a role in subsequent dissemination, although this role remains ill defined. Additionally, the disparate experimental approaches that have been used to probe various potential routes of BBB transit make it impossible to assess their relative contributions, confounding any integrated understanding of cryptococcal brain entry. Here we used an in vitro model BBB to show that a “Trojan horse” mechanism contributes significantly to fungal barrier crossing and that host factors regulate this process independently of free fungal transit. We also, for the first time, directly imaged C. neoformans-containing phagocytes crossing the BBB, showing that they do so via transendothelial pores. Finally, we found that Trojan horse crossing enables CNS entry of fungal mutants that cannot otherwise traverse the BBB, and we demonstrate additional intercellular interactions that may contribute to brain entry. Our work elucidates the mechanism of cryptococcal brain invasion and offers approaches to study other neuropathogens. IMPORTANCE The fungal pathogen Cryptococcus neoformans invades the brain, causing a meningoencephalitis that kills hundreds of thousands of people each year. One route that has been proposed for this brain entry is a Trojan horse mechanism, whereby the fungus crosses the blood-brain barrier (BBB) as a passenger inside host phagocytes. Although indirect experimental evidence supports this intriguing mechanism, it has never been directly visualized. Here we directly image Trojan horse transit and show that it is regulated independently of free fungal entry, contributes to cryptococcal BBB crossing, and allows mutant fungi that cannot enter alone to invade the brain. IMPORTANCE The fungal pathogen Cryptococcus neoformans invades the brain, causing a meningoencephalitis that kills hundreds of thousands of people each year. One route that has been proposed for this brain entry is a Trojan horse mechanism, whereby the fungus crosses the blood-brain barrier (BBB) as a passenger inside host phagocytes. Although indirect experimental evidence supports this intriguing mechanism, it has never been directly visualized. Here we directly image Trojan horse transit and show that it is regulated independently of free fungal entry, contributes to cryptococcal BBB crossing, and allows mutant fungi that cannot enter alone to invade the brain.

Understanding the Physiology of the Blood-Brain Barrier: In Vitro Models

Physiology ◽  
1998 ◽  
Vol 13 (6) ◽  
pp. 287-293 ◽  
Author(s):  
Gerald A. Grant ◽  
N. Joan Abbott ◽  
Damir Janigro
Keyword(s):  
Central Nervous System ◽  
Tissue Culture ◽  
Nervous System ◽  
Blood Brain Barrier ◽  
In Vitro Models ◽  
Brain Barrier ◽  
Blood Brain ◽  
Brain Tissue Culture ◽  
The Brain

Endothelial cells exposed to inductive central nervous system factors differentiate into a blood-brain barrier phenotype. The blood-brain barrier frequently obstructs the passage of chemotherapeutics into the brain. Tissue culture systems have been developed to reproduce key properties of the intact blood-brain barrier and to allow for testing of mechanisms of transendothelial drug permeation.

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