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METHYLATION OF THIONICOTINAMIDE FOR IMPROVED BLOOD BRAIN BARRIER PERMEABILITY IN THE TREATMENT OF CNS CANCERS

METHYLATION OF THIONICOTINAMIDE FOR IMPROVED BLOOD BRAIN BARRIER PERMEABILITY IN THE TREATMENT OF CNS CANCERS

The inhibition of NAD+ kinase (NADK) in cancer cells may represent a novel treatment strategy. Cytosolic NADK is an enzyme responsible for generating NADP, which is then rapidly converted to NADPH by reductases. Together, NAD and NADP are involved in a variety of cellular pathways, including metabolism, energy production, protein modification, and ROS detoxification. Treatment of cancer cells with thionicotinamide lowered NADPH pools, compromised biosynthetic capabilities, and inhibited cell growth. The 2D structure of thionicotinamide was obtained from the PubChem database and sketched alongside its methylated analogue using the ChemAxon software. The in-silico pharmacokinetic parameters of the compounds were predicted using the SwissADME online server. This was also used to construct the boiled-egg plot which confirmed the blood brain barrier permeability of the two compounds. Results from the in-silico pharmacokinetics parameters obtained from the SwissADME prediction showed that the methylated analogue of thionicotinamide might be a better therapeutic option for the treatment of CNS cancers as it showed an improved blood brain barrier permeability propertiy.

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Inhibition of 2-AG hydrolysis differentially regulates blood brain barrier permeability after injury

Inhibition of 2-AG hydrolysis differentially regulates blood brain barrier permeability after injury

Activation of the neurovasculature through inflammatory challenge has previously been shown to disrupt the integrity of the BBB and substantially induce its permeability [3, 22]. After systemic LPS administration, brain vasculature was isolated and extracted RNA was analyzed by next generation sequencing for gene expression quantification. The RNA-seq analysis identified 949 differentially regulated genes (false discovery rate ≤ 0. 05, increased or decreased by at least twofold) by LPS challenge compared to vehicle controls (Fig. 1b and Additional file 1: Table S1). Among those, 745 were statisti- cally significantly upregulated, and 204 were significantly downregulated. The GO analysis of the upregulated genes using DAVID bioinformatics tools identified the top three enriched functional annotation clusters as inflammatory re- sponse, regulation of cytokine production, and immune re- sponse (Fig. 1c and Additional file 2: Table S2). The inflammatory response cluster contained genes pertaining to TLR (Toll-like receptor) signaling and inflammasome ac- tivation as expected in an LPS challenge model. The cyto- kine regulation and immune response clusters contained a number of genes coding for cytokines, chemokines, and complement system proteins. Of the LPS downregulated genes, there were no statistically significant clusters identi- fied (Additional file 2: Table S2), and therefore in this study, we only focus on the upregulated genes.

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Application of Blood Brain Barrier Permeability Imaging in Global Cerebral Edema

Application of Blood Brain Barrier Permeability Imaging in Global Cerebral Edema

Disclosures: Jana Ivanidze—RELATED: Grant: Radiological Society of North America Research and Education Foundation,* Comments: Resident Research Grant 2014 – 2015. Ajay Gupta—RELATED: Grant: CTSC Pilot Award (NIH/NCATS Grant # UL1TR00457)*; UNRELATED: Grants/Grants Pending: Foundation of the American Society of Neuroradiology Scholar Award.* Jan Claassen—UNRELATED: Consul- tancy: Actelion, Sage, Comments: Advisory board for study planning. Pina C. Sanelli—RELATED: Grant: Brain Aneurysm Foundation Grant 2014 –2015. *Money paid to the institution.

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Alterations in Blood Brain Barrier Permeability in Patients with Systemic Lupus Erythematosus

Alterations in Blood Brain Barrier Permeability in Patients with Systemic Lupus Erythematosus

When we qualitatively compared the generated mean dynamic contrast-enhancement curves in the different brain regions, pa- tients with SLE demonstrated increased BBBP, specifically in the hippocampal region compared with healthy controls (Fig 3). Comparison of the mean area under the curve for patients with SLE and healthy controls revealed a statistically significant in- creased BBB permeability only in the hippocampal region (P ⫽ .02). All other brain regions demonstrated no statistically signifi- cant difference in the patients with SLE and healthy controls in the orbitofrontal (P ⫽ .72), prefrontal (P ⫽ .55), posterior putamen/ globus pallidus/thalamus (P ⫽ .83), and anterior putamen/cau- date (P ⫽ .60). Furthermore, model-based quantitative data re- vealed that patients with SLE have statistically significant increased K trans (P ⫽ .04), Ve (P ⫽ .04), and CBF (P ⫽ .01) in the

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Evaluating Permeability Surface Area Product as a Measure of Blood Brain Barrier Permeability in a Murine Model

Evaluating Permeability Surface Area Product as a Measure of Blood Brain Barrier Permeability in a Murine Model

Contrast-enhancement data and curves were generated for comparison with PS findings (Fig 4). Contrast-enhancement curves and quantitative data represent the contrast extravasation into the extravascular extracellular tissue of the brain. The highest peaks of contrast-enhancement curves were seen in the PCA ter- ritory in both mannitol-treated and saline control mice and cor- responded to the high absolute PS values measured in these re- gions. A statistically significant moderate correlation was found between absolute PS with area under the tissue density curve and peak enhancement over baseline separately (R ⫽ 0.61, R ⫽ 0.58, P ⬍ .0001) (Fig 5), as well as between the PS ratio with area under the tissue density curve and peak enhancement over baseline (R ⫽ 0.50, R ⫽ 0.59, P ⬍ .0001).

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Image-guided chemotherapy with specifically tuned blood brain barrier permeability in glioma margins

Image-guided chemotherapy with specifically tuned blood brain barrier permeability in glioma margins

Although uncompromised BBB in the glioma margin is believed to be the primary cause of the low chemotherapeutic efficiency [17], there is insufficient clinical evidence to support this notion. To address this issue, ZO-1, a key TJ-associated protein that determines BBB integrity, was immuno-stained in the marginal regions of low-grade glioma (LGG) and high-grade glioma (HGG) from patients, as well as in control brain tissues (Figure 1A). While ZO-1 immunity was presented as well-regulated zebra-strips twining around vascular endothelium in control brain tissues, its disrupted distribution and attenuated expression level in glioma margins were evident. Nevertheless, capillaries with unspoiled ZO-1 immunity were still present in the marginal territories regardless of the malignancy grade. The capillary percentage with intact ZO-1 was decreased from 74.1% in control brain tissues to 48.5% in LGG and 23.7% in HGG (Figure 1B). The highest ZO-1 expression level was found in control brain tissues, which was 1.45- and 3.17-fold higher than that in LGG and HGG respectively (Figure 1C). Representative

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The age related deficit in LTP is associated with changes in perfusion and blood brain barrier permeability

The age related deficit in LTP is associated with changes in perfusion and blood brain barrier permeability

In view of the increase in the aging population and the unavoidable parallel increase in the incidence of age-related neurodegenerative diseases, a key challenge in neuroscience is the identification of clinical signatures which change with age and impact on neuronal and cognitive function. Early diagnosis offers the possibility of early therapeutic intervention, thus magnetic resonance imaging (MRI) is potentially a powerful diagnostic tool. We evaluated age-related changes in relaxometry, blood flow, and blood-brain barrier (BBB) permeability in the rat by magnetic resonance imaging and assessed these changes in the context of the age-related decrease in synaptic plasticity. We report that T2 relaxation time was decreased with age; this was coupled with a decrease in gray matter perfusion, suggesting that the observed microglial activation, as identified by increased expression of CD11b, MHCII, and CD68 by immunohistochemistry, flow cytometry, or polymerase chain reaction (PCR), might be a downstream consequence of these changes. Increased permeability of the blood-brain barrier was observed in the perivascular area and the hippocampus of aged, compared with young, rats. Similarly there was an age-related increase in CD45-positive cells by flow cytometry, which are most likely infiltrating macrophages, with a parallel increase in the messenger mRNA expression of chemokines IP-10 and MCP-1. These combined changes may contribute to the deficit in long-term potentiation (LTP) in perforant path-granule cell synapses of aged animals.

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Blood-brain barrier permeability of gefitinib in patients with brain metastases from non-small-cell lung cancer before and during whole brain radiation therapy

Blood-brain barrier permeability of gefitinib in patients with brain metastases from non-small-cell lung cancer before and during whole brain radiation therapy

of different durations. The relationships between CSF and serum concentrations of gefetinib were determined by linear regression. The survival curves were generated using the Kaplan–Meier method. Univariate analysis of patient characteristics and tumor responses was conducted by Pearson chi-square test or the Fisher exact test. Multivariate analysis was evaluated using a logistic regression model to predict the clinical response to the treatment regimen. The following variables were included: gender, age, performance status, smoking history, number and size of brain metastases, EGFR mutation status, and extracranial metastases. The Cox regression method was used to identify the most important independent prognostic factors and estimate the hazard ratio. All tests and confidence intervals (CIs) were two sided and a significance level was 0.05. Statistical analyses were performed by using SPSS software, Version 13.0.

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Mannitol and the blood-labyrinth barrier

Mannitol and the blood-labyrinth barrier

The guinea pig was chosen because its hearing and ves- tibular systems are very similar to those of humans, as well as its ease of handling and large size of the cochlea [17]. A total of 175 samples of perilymph, blood and CSF were collected from 44 Dunkin-Hartley guinea pigs (Charles River Breeding Lab, Senneville) with jugular vein catheters placed for intravenous injection. Samples were taken from two groups of 22 animals, each at dif- ferent times after administration of either 10 mg/ml gen- tamicin (4 mg/kg) (Gardena, CA) alone or gentamicin with 20% mannitol (250 mg/kg) (Mallinckrodt Inc., KY). Samples were also taken from 4 animals as negative con- trols after administration of normal saline. Our goal was to simultaneously assess the pharmacokinetics of genta- micin in each of three different fluid samples. Each ani- mal was sampled once for perilymph, CSF, and blood before it was terminally collected at each individual post-infusion time varying from 0.5 to 17.5 h. Each ani- mal contributed to a single time point on the subsequent pharmacokinetic curves with more than one animal per time point.

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Free Radical Injury and Blood-Brain Barrier Permeability in Hypoxic-Ischemic Encephalopathy

Free Radical Injury and Blood-Brain Barrier Permeability in Hypoxic-Ischemic Encephalopathy

RESULTS. Plasma malondialdehyde and nitrate/nitrite levels were significantly higher in infants with hypoxic ischemic encephalopathy compared with control subjects. Although there was a progressive increment in plasma levels of malondialdehyde with increasing severity of hypoxic ischemic encephalopathy, the differences were not statistically significant. Plasma nitrate/nitrite levels were almost similar in all stages of hypoxic ischemic encephalopathy. Plasma albumin levels were comparable in infants with hypoxic ischemic encephalopathy and control subjects, whereas cerebrospinal fluid albumin levels and blood-brain barrier permeability were signif- icantly higher in infants with hypoxic ischemic encephalopathy. Significant correla- tion was observed between plasma malondialdehyde and nitrate/nitrite levels with blood-brain barrier permeability.

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Various in Vitro Models to Assess Drug Permeability Across the Blood Brain Barrier

Various in Vitro Models to Assess Drug Permeability Across the Blood Brain Barrier

Various invitro models are available that can be used to assess drug penetration across the BBB. Such model has its disadvantages and there needs to be a compromise between potential and the limitations associated with the chosen model. However inorder to fully assess the brain uptake of new chemical entity and to completely understand the mechanism involved in allowing or hindering BBB transport one should employ both invitro and invivo techniques and not rely solely on one method of screening.

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Original Article Bindarit alleviates inflammation and early brain injury following experimental subarachnoid hemorrhage in rats

Original Article Bindarit alleviates inflammation and early brain injury following experimental subarachnoid hemorrhage in rats

in the aggravation of neurological deficits and unfavorable prognosis after SAH [9]. The under- lying pathophysiological mechanisms of SAH- induced EBI are not definitely clarified to date. Researches of the mechanisms of EBI after SAH have demonstrated that the early neuroin- flammation is tightly associated with poor neu- rological grade on admission, malaise, fever, brain edema, increased blood brain barrier (BBB) permeability, thrombosis of small vessel, pathogenesis of vasospasm and delayed isch- emic neurologic deficits [10-13].

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Resistance of young gelatinase B–deficient mice to experimental autoimmune encephalomyelitis and necrotizing tail lesions

Resistance of young gelatinase B–deficient mice to experimental autoimmune encephalomyelitis and necrotizing tail lesions

Regulated expression of matrix metalloproteinases (MMPs) and their inhibitors (TIMPs) plays a role in various physiological processes. To determine in vivo how unbalanced expression of these factors can promote or affect the course of pathologies, we knocked out the mouse gelatinase B gene by replacing the catalytic and zinc-binding domains with an antisense-oriented neomycin resistance gene. Adult gelatinase B–deficient mice and wild- type controls could be induced to develop experimental autoimmune encephalomyelitis (EAE) with similar scores for neurologic disease, blood-brain barrier permeability, and central nervous system histopathology. However, whereas diseased control animals showed necrotizing tail lesions with hyperplasia of osteocartilaginous tissue, adult gelatinase B–deficient mice were resistant to this tail pathology. Gelatinase B–deficient mice younger than 4 weeks of age were significantly less susceptible to the development of EAE than were age matched controls and, even as they aged, they remained resistant to tail lesions. These data illustrate that gelatinase B expression plays a role in the development of the immune system and that, in ontogenesis, the propensity to develop autoimmunity is altered by the absence of this MMP.

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NIH workshop report on the trans-agency blood–brain interface workshop 2016: exploring key challenges and opportunities associated with the blood, brain and their interface

NIH workshop report on the trans-agency blood–brain interface workshop 2016: exploring key challenges and opportunities associated with the blood, brain and their interface

A key challenge for the BBB field is the limited under- standing of the consequences of blood proteins in the CNS and their contribution to neuronal dysfunction. Protection of the CNS from leakage of plasma proteins by the BBB is compromised in a wide range of neuroim- mune and neurodegenerative diseases, as well as after TBI. Dr. Katerina Akassoglou identified fibrinogen as a novel molecular link between blood and brain barrier disruption (BBBD), activation of CNS innate immunity, and neurodegeneration (Fig. 1d) [17]. Following fibrino- gen conversion to pro-inflammatory fibrin, the CD11b/ CD18 integrin receptor (also known as Mac-1 and com- plement receptor 3) is activated on microglial cells [18, 19]. Genetic disruption of the fibrin/CD11b interaction suppresses this microglial activation process and results in a reduction of neurologic symptoms, inflammation, demyelination, and axonal damage in experimental auto- immune encephalomyelitis (EAE) [17, 20, 21]. Dr. Akas- soglou concluded that targeting the functions of fibrin in the CNS without affecting its beneficial effects in hemo- stasis holds promise for therapeutic intervention, and suggested that studies of fibrin-induced neuroinflamma- tion in neurological diseases associated with fibrin depo- sition and microglial activation, such as TBI and AD, are also warranted.

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Efficient Enhancement of Blood-Brain Barrier Permeability Using Acoustic Cluster Therapy (ACT)

Efficient Enhancement of Blood-Brain Barrier Permeability Using Acoustic Cluster Therapy (ACT)

With the ultrasound activation and enhancement regimes applied, the ACT treatment clearly induced a significantly higher extravasation of gadodiamide to the brain than regular, small contrast microbubbles. Several important distinctions may contribute to this difference in effect level. The ACT-bubbles are in close contact with the endothelium over a significant segment of the vessel wall, ensuring a large interfacing area between the oscillating bubble and the endothelial cells. Sonazoid™, on the other hand, is free flowing and the average distance between the microbubble surface and the endothelial cells may limit the biomechanical effect level. ACT-bubbles are approximately 1000 times larger (by volume) than Sonazoid™ microbubbles and the biomechanical effects these large bubbles induce, even at low ultrasound pressures, should be orders of magnitude larger than with regular contrast microbubbles. Moreover, the lodged ACT-bubble will cause an increased microvascular pressure on the arterial side of the bubble and the induced transcapillary pressure gradient will enhance extravasation.

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Edaravone-Encapsulated Agonistic Micelles Rescue Ischemic Brain Tissue by Tuning Blood-Brain Barrier Permeability

Edaravone-Encapsulated Agonistic Micelles Rescue Ischemic Brain Tissue by Tuning Blood-Brain Barrier Permeability

PBS, EDV-PM or free EDV, respectively, (n = 5). It is of note that while the infarct volume decreased remarkably from 24.9 ± 1.8% at day 7 to 13.9 ± 3.6% at day 14 post EDV-AM treatment, the ischemic area was barely changed in the groups treated with free EDV or EDV-PM after excluding the spontaneous rehabilitation (Figure 5B). The pathological BBB permeability enhancement in brain ischemia was reported to occur as a biphasic response [23]. The first phase, occurring in 2−8 hours after stroke onset, was induced by the ROS-triggered TJ protein degradation. The second phase occurred 18−96 hours later and was a result of vasogenic edema and angiogenesis. Notably, while EDV-AM, EDV-PM, and free EDV all were remarkably reduced ischemic volume in the first 4 days after treatment, obvious neuroprotective effects from day 7 to day 14 was only observed after EDV-AM treatment. The positive therapeutic effect in the first 4 days could be partially explained by the enhanced EDV brain uptake because of the pathologically compromised BBB. The recovered BBB integrity from day 7 to day 14 prevents the cerebral uptake of EDV and EDV-PM which could explain why only EDV-AM with BBB permeability showed the neuroprotective effect. Our studies showed the feasibility to extend the therapeutic time-window of ischemic stroke via the agonistic micelles-mediated brain delivery of neuroprotectants.

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The Interaction of Stroke Risk Factors, Clinical Outcomes and Matrix Metalloproteinase 9 Levels with the Reduction of Vascular Endothelial Growth Factor A Levels at the Incidence of Brain Edema in Acute Ischemic Stroke Patients

The Interaction of Stroke Risk Factors, Clinical Outcomes and Matrix Metalloproteinase 9 Levels with the Reduction of Vascular Endothelial Growth Factor A Levels at the Incidence of Brain Edema in Acute Ischemic Stroke Patients

For the role of blood glucose within the interaction of VEGF-A to the incidence of brain edema, Table 3 shows that the influence was greater, but not statistically different, at the level of glucose >126 mmol/L (OR=6.33) than at the level <126 mmol/L (OR=1.82). The subsequent chi-square analysis suggested that the blood glucose level was a significant confounding factor to the correlation between VEGF-A and brain edema since the OR was equal to the crude OR (3.6 versus 3.6; 95%CI: 1.19-10.71; p=0.019). Pertaining to the role of LDL within the interaction of VEGF-A to the incidence of brain edema, Table 3 shows that the influence was greater, but not statistically different, at the level of LDL <160 mmol/L (OR=5.18) than at the level >160 mmol/L (OR=2.3). The subsequent chi- square analysis revealed that the LDL level was a significant interacting factor to the correlation between VEGF-A and brain edema since the OR was greater than the crude OR (4.1 versus 3.6; 95%CI: 1.29-13.08; p=0.015). This finding was in contrast to the roles of total cholesterol, HDL and triglyceride, in which the analysis indicated the latter three variables most likely served as the confounding factors.

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Original Article Neuroprotective effect of riluzole in rat model of subarachnoid hemorrhage

Original Article Neuroprotective effect of riluzole in rat model of subarachnoid hemorrhage

Abstract: Riluzole, an anti-glutamate drug and sodium channel blocker with neuroprotective roles, which has been approved by US Food and Drug Administration (FDA) for amyotrophic lateral sclerosis. The purpose of this study was to explore whether Riluzole provides neuroprotection in early brain injury (EBI) after subarachnoid hemorrhage (SAH). Intraperitoneal injection of Riluzole (6 mg/kg) significantly improved neurological deficit at 24, 48 and 72 h. Riluzole alleviated the blood brain barrier (BBB) permeability of cortex and brain edema, also reduced the glu- tamate concentration of cerebrospinal fluid, increased the GLT-1 expression of cortex, increased GSH content and attenuated MDA content and neuronal apoptosis of cortex at 72 h after SAH. These results suggested that Riluzole treatment may ameliorate early brain injury in experimental SAH model.

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Brain pericytes from stress-susceptible pigs increase blood-brain barrier permeability in vitro

Brain pericytes from stress-susceptible pigs increase blood-brain barrier permeability in vitro

To study BBB in PSS brains, ultrastructural investiga- tions of the cerebral capillaries were performed in the three ryr1 genotypes of pigs (NN, wild type; Nn and nn, carrying one and two mutant alleles respectively). Cellu- lar and molecular interactions between different cell types within the BBB can more easily be studied in vitro. However, there has been a delayed interest in pericytes and the major reason is due to the fact that to obtain pure endothelial cell cultures, pericytes have to be elimi- nated during the isolation process. Now that cell culture techniques allow the production of pure endothelial cul- tures on the one hand and of pure pericyte cultures on the other hand, pericytes can easily be studied in vitro, alone or in coculture with other cell types [6-8]. In vitro models using both brain endothelial cells and brain peri- cytes have shown that pericytes are able to regulate tight junction (TJ) protein expression in endothelial cells (ECs) [9-11], and also the expression of transporters [12,13]. Therefore in this study, brain pericytes were extracted from the three porcine genotypes and studied for their

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 GLIOBLASTOMA MULTIFORME: A REVIEW OF ITS PATHOGENESIS AND TREATMENT

 GLIOBLASTOMA MULTIFORME: A REVIEW OF ITS PATHOGENESIS AND TREATMENT

commonly affected by glioblastoma multiforme, with an incidence rate of almost 1.6 times higher than in females.GBM can take place at any age however, the peak incidence is between 55 to 74 years. Anaplastic astrocytomas occur in younger adults between ages 30 -50 and account for 17% of primary malignant brain tumors. Only 9% of brain tumors in children are glioblastomas. 1 to 7% of people with glioblastomas and 4% of people with anaplastic astrocytomas are found to have multiple tumours at the time of diagnosis. The incidence of gliomas is usually higher in the western world compared to less developed countries that could be due to under reporting of gliomas cases, limited access to health care and differences in diagnostic practices 13, 14 .

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