Development of an Intact Blood-Brain Barrier in Brain Tissue Transplants is Dependent on the Site of Transplantation

Transplantation of fetal septal forebrain tissue was performed to the anterior chamber of the eye, or intracranially to the rostral hippocampal formation in rats, to evaluate the impact of transplantation site on the development of an intact blood–brain barrier (BBB). The tissue was studied at 1, 2, 3, and 4 wk following transplantation by means of intravenous injection of Trypan blue, which is a vital stain not normally penetrating the BBB, as well as with an antibody specifically directed against the rat BBB, SMI71. In the intraocular septal transplants, there was a significant leakage of Trypan blue 1 wk postgrafting, associated with a few laminin-immunoreactive blood vessels that did not contain any SMI71-immunoreactivity. However, at 2 wk postgrafting, the intraocular grats exhibited an extensive plexus of thin-walled blood vessels expressing SMI71 immunoreactivity and no Trypan blue leakage. Thus, it appeared that a BBB had developed to some degree by 2 wk postgrafting in oculo. In the intracranial grafts, on the other hand, Trypan blue leakage could be seen as long as 3 wk postgrafting, and a dense plexus of blood vessels with SMI71 immunoreactivity was first seen at 4 wk postgrafting. Thus, the development of Trypan blue impermeability was delayed with 1 to 2 wk in the intracranial versus the intraocular grafts. Control experiments using psychological stress in adult rats as a means to transiently disrupt the BBB revealed that an increase in Trypan blue leakage correlated well with the disappearance of SMI71 immunoreactivity. Taken together, these studies demonstrate that the site of transplantation can influence the development of an intact BBB in neural tissue grafts.

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Immunolocalization of Heat Shock Protein after Fluid Percussive Brain Injury and Relationship to Breakdown of the Blood-Brain Barrier

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.1993.14 ◽

1993 ◽

Vol 13 (1) ◽

pp. 116-124 ◽

Cited By ~ 68

Author(s):

Hirokazu Tanno ◽

Russ P. Nockels ◽

Lawrence H. Pitts ◽

Linda J. Noble

Keyword(s):

Brain Injury ◽

Head Injury ◽

Blood Vessels ◽

Blood Brain Barrier ◽

Time Course ◽

Cortical Layer ◽

Brain Barrier ◽

Impact Site ◽

Blood Brain ◽

The Impact

We have previously developed a model of mild, lateral fluid percussive head injury in the rat and demonstrated that although this injury produced minimal hemorrhage, breakdown of the blood–brain barrier was a prominent feature. The relationship between posttraumatic blood–brain barrier disruption and cellular injury is unclear. In the present study we examined the distribution and time course of expression of the stress protein HSP72 after brain injury and compared these findings with the known pattern of breakdown of the blood–brain barrier after a similar injury. Rats were subjected to a lateral fluid percussive brain injury (4.8–5.2 atm, 20 ms) and killed at 1, 3, and 6 h and 1,3, and 7 days after injury. HSP72-like immunoreactivity was evaluated in sections of brain at the light-microscopic level. The earliest expression of HSP72 occurred at 3 h postinjury and was restricted to neurons and glia in the cortex surrounding a necrotic area at the impact site. By 6 h, light immunostaining was also noted in the pia-arachnoid adjacent to the impact site and in certain blood vessels that coursed through the area of necrosis. Maximal immunostaining was observed by 24 h postinjury, and was primarily associated with the cortex immediately adjacent to the region of necrosis at the impact site. This region consisted of darkly immunostained neurons, glia, and blood vessels. Immunostaining within the region of necrosis was restricted to blood vessels. HSP72-like immunoreactivity was also noted in a limited number of neurons and glia in other brain regions, including the parasagittal cortex, deep cortical layer VI, and CA3 in the posterior hippocampus. Immunoreactive cells in these areas were not apparent until 24 h postinjury. By 7 days postinjury, HSP72-like immunoreactivity was minimal or absent in these injured brains and notable cell loss was apparent only in the impact site. This study demonstrates an early and pronounced expression of HSP72 at the impact site and a more delayed and less prominent expression of this protein in other regions of the brain. These findings parallel the temporal and regional pattern of breakdown of the blood–brain barrier after a similar head injury.

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Effects of Neonatal Systemic Inflammation on Blood-Brain Barrier Permeability and Behaviour in Juvenile and Adult Rats

Cardiovascular Psychiatry and Neurology ◽

10.1155/2011/469046 ◽

2011 ◽

Vol 2011 ◽

pp. 1-10 ◽

Cited By ~ 32

Author(s):

H. B. Stolp ◽

P. A. Johansson ◽

M. D. Habgood ◽

K. M. Dziegielewska ◽

N. R. Saunders ◽

...

Keyword(s):

Blood Brain Barrier ◽

Systemic Inflammation ◽

Brain Barrier ◽

Adult Rats ◽

Dark Light ◽

Barrier Permeability ◽

Blood Brain Barrier Permeability ◽

Blood Brain ◽

Brain Barrier Permeability ◽

The Impact

Several neurological disorders have been linked to inflammatory insults suffered during development. We investigated the effects of neonatal systemic inflammation, induced by LPS injections, on blood-brain barrier permeability, endothelial tight junctions and behaviour of juvenile (P20) and adult rats. LPS-treatment resulted in altered cellular localisation of claudin-5 and changes in ultrastructural morphology of a few cerebral blood vessels. Barrier permeability to sucrose was significantly increased in LPS treated animals when adult but not at P20 or earlier. Behavioural tests showed that LPS treated animals at P20 exhibited altered behaviour using prepulse inhibition (PPI) analysis, whereas adults demonstrated altered behaviour in the dark/light test. These data indicate that an inflammatory insult during brain development can change blood-brain barrier permeability and behaviour in later life. It also suggests that the impact of inflammation can occur in several phases (short- and long-term) and that each phase might lead to different behavioural modifications.

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Blood–brain barrier disruption and ventricular enlargement are the earliest neuropathological changes in rats with repeated sub-concussive impacts over 2 weeks

Scientific Reports ◽

10.1038/s41598-021-88854-9 ◽

2021 ◽

Vol 11 (1) ◽

Author(s):

Bailey Hiles-Murison ◽

Andrew P. Lavender ◽

Mark J. Hackett ◽

Joshua J. Armstrong ◽

Michael Nesbit ◽

...

Keyword(s):

Oxidative Stress ◽

Blood Brain Barrier ◽

Hippocampal Formation ◽

Brain Barrier ◽

Lateral Ventricles ◽

Blood Brain Barrier Disruption ◽

Blood Brain ◽

Brain Barrier Disruption ◽

Underlying Mechanisms

AbstractRepeated sub-concussive impact (e.g. soccer ball heading), a significantly lighter form of mild traumatic brain injury, is increasingly suggested to cumulatively alter brain structure and compromise neurobehavioural function in the long-term. However, the underlying mechanisms whereby repeated long-term sub-concussion induces cerebral structural and neurobehavioural changes are currently unknown. Here, we utilised an established rat model to investigate the effects of repeated sub-concussion on size of lateral ventricles, cerebrovascular blood–brain barrier (BBB) integrity, neuroinflammation, oxidative stress, and biochemical distribution. Following repeated sub-concussion 3 days per week for 2 weeks, the rats showed significantly enlarged lateral ventricles compared with the rats receiving sham-only procedure. The sub-concussive rats also presented significant BBB dysfunction in the cerebral cortex and hippocampal formation, whilst neuromotor function assessed by beamwalk and rotarod tests were comparable to the sham rats. Immunofluorescent and spectroscopic microscopy analyses revealed no significant changes in neuroinflammation, oxidative stress, lipid distribution or protein aggregation, within the hippocampus and cortex. These data collectively indicate that repeated sub-concussion for 2 weeks induce significant ventriculomegaly and BBB disruption, preceding neuromotor deficits.

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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 ◽

10.3390/pharmaceutics13060892 ◽

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.

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PATH-04. THE BLOOD-BRAIN BARRIER IN DIFFUSE MIDLINE GLIOMA AND ITS IMPLICATIONS FOR DRUG DELIVERY

Neuro-Oncology ◽

10.1093/neuonc/noaa215.686 ◽

2020 ◽

Vol 22 (Supplement_2) ◽

pp. ii164-ii164

Author(s):

Rianne Haumann ◽

Fatma El-Khouly ◽

Marjolein Breur ◽

Sophie Veldhuijzen van Zanten ◽

Gertjan Kaspers ◽

...

Keyword(s):

Drug Delivery ◽

Blood Vessels ◽

Blood Brain Barrier ◽

Brain Barrier ◽

Vascular Density ◽

Zonula Occludens ◽

Blood Brain ◽

Zonula Occludens 1 ◽

End Stage ◽

Diffuse Midline Glioma

Abstract INTRODUCTION Chemotherapy has been unsuccessful for pediatric diffuse midline glioma (DMG) most likely due to an intact blood-brain barrier (BBB). However, the BBB has not been characterized in DMG and therefore its implications for drug delivery are unknown. In this study we characterized the BBB in DMG patients and compared this to healthy controls. METHODS End-stage DMG pontine samples (n=5) were obtained from the VUmc diffuse intrinsic pontine glioma (DIPG) autopsy study and age-matched healthy pontine samples (n=22) were obtained from the NIH NeuroBioBank. Tissues were stained for BBB markers claudin-5, zonula occludens-1, laminin, and PDGFRβ. Claudin-5 stains were used to determine vascular density and diameter. RESULTS In DMG, expression of claudin-5 was reduced and dislocated to the abluminal side of endothelial cells. In addition, the expression of zonula occludens-1 was reduced. The basement membrane protein laminin expression was reduced at the glia limitans in both pre-existent vessels and neovascular proliferation. PDGFRβ expression was not observed in DMG but was present in healthy pons. Furthermore, the number of blood vessels in DMG was significantly (P< 0.01) reduced (13.9 ± 11.8/mm2) compared to healthy pons (26.3 ± 14.2/mm2). Markedly, the number of small blood vessels (< 10µm) was significantly lower (P< 0.01) while larger blood vessels (> 10µm) were not significantly different (P= 0.223). The mean vascular diameter was larger for DMG 9.3 ± 9.9µm compared to 7.7 ± 9.0µm for healthy pons (P= 0.016). CONCLUSION Both the BBB and the vasculature are altered at end-stage DMG. The reduced vascular density might have implications for several drug delivery methods such as focused ultrasound and convection enhanced delivery that are being explored for the treatment of DMG. The functional effects of the structurally altered BBB remain unknown and further research is needed to evaluate the BBB integrity at end-stage DMG

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CdSe/ZnS Core-Shell-Type Quantum Dot Nanoparticles Disrupt the Cellular Homeostasis in Cellular Blood–Brain Barrier Models

International Journal of Molecular Sciences ◽

10.3390/ijms22031068 ◽

2021 ◽

Vol 22 (3) ◽

pp. 1068

Author(s):

Katarzyna Dominika Kania ◽

Waldemar Wagner ◽

Łukasz Pułaski

Keyword(s):

Gene Expression ◽

Quantum Dot ◽

Blood Brain Barrier ◽

Protein Gene ◽

Brain Barrier ◽

Core Shell ◽

Cellular Homeostasis ◽

Blood Brain ◽

Shell Type ◽

The Impact

Two immortalized brain microvascular endothelial cell lines (hCMEC/D3 and RBE4, of human and rat origin, respectively) were applied as an in vitro model of cellular elements of the blood–brain barrier in a nanotoxicological study. We evaluated the impact of CdSe/ZnS core-shell-type quantum dot nanoparticles on cellular homeostasis, using gold nanoparticles as a largely bioorthogonal control. While the investigated nanoparticles had surprisingly negligible acute cytotoxicity in the evaluated models, a multi-faceted study of barrier-related phenotypes and cell condition revealed a complex pattern of homeostasis disruption. Interestingly, some features of the paracellular barrier phenotype (transendothelial electrical resistance, tight junction protein gene expression) were improved by exposure to nanoparticles in a potential hormetic mechanism. However, mitochondrial potential and antioxidant defences largely collapsed under these conditions, paralleled by a strong pro-apoptotic shift in a significant proportion of cells (evidenced by apoptotic protein gene expression, chromosomal DNA fragmentation, and membrane phosphatidylserine exposure). Taken together, our results suggest a reactive oxygen species-mediated cellular mechanism of blood–brain barrier damage by quantum dots, which may be toxicologically significant in the face of increasing human exposure to this type of nanoparticles, both intended (in medical applications) and more often unintended (from consumer goods-derived environmental pollution).

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Restraint Stress-Induced Morphological Changes at the Blood-Brain Barrier in Adult Rats

Frontiers in Molecular Neuroscience ◽

10.3389/fnmol.2015.00088 ◽

2016 ◽

Vol 8 ◽

Cited By ~ 25

Author(s):

Petra Sántha ◽

Szilvia Veszelka ◽

Zsófia Hoyk ◽

Mária Mészáros ◽

Fruzsina R. Walter ◽

...

Keyword(s):

Blood Brain Barrier ◽

Restraint Stress ◽

Morphological Changes ◽

Brain Barrier ◽

Adult Rats ◽

Blood Brain

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Intracerebral Hemorrhage and Diabetes Mellitus: Blood-Brain Barrier Disruption, Pathophysiology, and Cognitive Impairments

CNS & Neurological Disorders - Drug Targets ◽

10.2174/1871527320666210223145112 ◽

2021 ◽

Vol 20 ◽

Author(s):

Ghaith A. Bahadar ◽

Zahoor A Shah

Keyword(s):

Diabetes Mellitus ◽

Intracerebral Hemorrhage ◽

Blood Brain Barrier ◽

Brain Barrier ◽

Comorbid Condition ◽

Barrier Disruption ◽

Blood Brain Barrier Disruption ◽

Blood Brain ◽

Brain Barrier Disruption ◽

The Impact

: There is a surge in diabetes incidence with an estimated 463 million individuals been diagnosed worldwide. Diabetes Mellitus (DM) is a major stroke-related comorbid condition that increases the susceptibility of disabling post-stroke outcomes. Although less common, intracerebral hemorrhage (ICH) is the most dramatic subtype of stroke that is associated with higher mortality, particularly in DM population. Previous studies have focused mainly on the impact of DM on ischemic stroke. Few studies have focused on impact of DM on ICH and discussed the blood-brain barrier disruption, brain edema, and hematoma formation. However, more recently, investigating the role of oxidative damage and reactive oxygen species (ROS) production in preclinical studies involving DM-ICH animal models has gained attention. But, little is known about the correlation between neuroinflammatory processes, glial cells activation, and peripheral immune cell invasion with DM-ICH injury. DM and ICH patients experience impaired abilities in multiple cognitive domains by relatively comparable mechanisms, which could get exacerbated in the setting of comorbidities. In this review, we discuss both the pathology of DM as a comorbid condition for ICH and the potential molecular therapeutic targets for the clinical management of the ICH and its recovery.

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