Protein Nanoparticle Osmotic Pressure Modifies Nonselective Permeability of the Blood Brain Barrier by Increasing Membrane Fluidity

Abstract BackgroundIntracellular tension plays a crucial role in the destruction of the blood brain barrier (BBB) in response to lesion stimuli. Tight junction structure could be primarily affected by tension activity. In this study, we aimed to determine the effects of extracellular BBB damage on intracellular tension activity, and elucidate the mechanism underlying the effects of intracellular protein nanoparticle-dependent osmotic pressure on BBB permeability.MethodsThe intracellular tension for tight junction proteins occludin and ZO1 were evaluated using the fluorescence resonance energy transfer (FRET)-based tension probes and cpstFRET analysis. The efficiency of the probes was examined by acceptor photobleaching FRET (FRET-AB) analysis. The changes in mobility ratios of the transmembrane protein occludin were evaluated via the fluorescence recovery after photobleaching (FRAP) test. The cytoplasmic osmotic pressure (OP) was measured using the Osmomat 3000 Freezing Point Osmometer and 050 Membrane Osmometer. The count rate of cytoplasmic nanoparticles was detected by Nanosight NS300. The activation of cofilin and stathmin was examined by Western blot analysis. The BBB permeability in vivo was determined via investigating the changes of Evans Blue (EB) injected into the SD rats. The tight junction formation was assessed by the measurement of transendothelial electrical resistance (TEER). Intracellular calcium or chloride ions were measured using Fluo-4 AM or MQAE dyes. ResultsBBB lesions were accompanied by changes in occludin/ZO1 tension. Increases in intracellular osmotic pressure were involved in alteration of BBB permeability, possibly through the depolymerization of microfilaments or microtubules and mass production of protein nanoparticles according to the Donnan effect. Recovery of protein nanoparticle osmotic pressure could effectively reverse the effects of changes in occludin/ZO1 tension and BBB lesions. Outward tension of intracellular osmotic potential also caused upregulation of membrane fluidity, which promoted nonselective drug influx.ConclusionsOur results suggest a crucial mechanical mechanism underlying BBB lesions, and protein nanoparticle osmotic pressure could be a novel therapeutic target for BBB lesion-related brain diseases. Our results also provide a basis for further studies on the regulation of intracellular tension activity and its effect on the permeability of the BBB, and development of novel drugs that cross the blood-brain barrier.

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Angiogenesis and Blood-Brain Barrier Permeability in Vascular Remodeling after Stroke

Current Neuropharmacology ◽

10.2174/1570159x18666200720173316 ◽

2020 ◽

Vol 18 (12) ◽

pp. 1250-1265 ◽

Cited By ~ 2

Author(s):

Yi Yang ◽

Michel T. Torbey

Keyword(s):

Tight Junction ◽

Blood Brain Barrier ◽

Defense Mechanism ◽

Vascular Endothelial Cells ◽

Brain Plasticity ◽

Normal Function ◽

Brain Barrier ◽

Neurologic Recovery ◽

Blood Brain ◽

Bbb Permeability

Angiogenesis, the growth of new blood vessels, is a natural defense mechanism helping to restore oxygen and nutrient supply to the affected brain tissue following an ischemic stroke. By stimulating vessel growth, angiogenesis may stabilize brain perfusion, thereby promoting neuronal survival, brain plasticity, and neurologic recovery. However, therapeutic angiogenesis after stroke faces challenges: new angiogenesis-induced vessels have a higher than normal permeability, and treatment to promote angiogenesis may exacerbate outcomes in stroke patients. The development of therapies requires elucidation of the precise cellular and molecular basis of the disease. Microenvironment homeostasis of the central nervous system is essential for its normal function and is maintained by the blood-brain barrier (BBB). Tight junction proteins (TJP) form the tight junction (TJ) between vascular endothelial cells (ECs) and play a key role in regulating the BBB permeability. We demonstrated that after stroke, new angiogenesis-induced vessels in peri-infarct areas have abnormally high BBB permeability due to a lack of major TJPs in ECs. Therefore, promoting TJ formation and BBB integrity in the new vessels coupled with speedy angiogenesis will provide a promising and safer treatment strategy for improving recovery from stroke. Pericyte is a central neurovascular unite component in vascular barriergenesis and are vital to BBB integrity. We found that pericytes also play a key role in stroke-induced angiogenesis and TJ formation in the newly formed vessels. Based on these findings, in this article, we focus on regulation aspects of the BBB functions and describe cellular and molecular special features of TJ formation with an emphasis on role of pericytes in BBB integrity during angiogenesis after stroke.

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Borneol for Regulating the Permeability of the Blood-Brain Barrier in Experimental Ischemic Stroke: Preclinical Evidence and Possible Mechanism

Oxidative Medicine and Cellular Longevity ◽

10.1155/2019/2936737 ◽

2019 ◽

Vol 2019 ◽

pp. 1-15 ◽

Cited By ~ 9

Author(s):

Zi-xian Chen ◽

Qing-qing Xu ◽

Chun-shuo Shan ◽

Yi-hua Shi ◽

Yong Wang ◽

...

Keyword(s):

Ischemic Stroke ◽

Blood Brain Barrier ◽

Ischemic Injury ◽

Brain Barrier ◽

Brain Diseases ◽

Glycoprotein P ◽

Blood Brain ◽

Cerebral Ischemic Injury ◽

Bbb Permeability ◽

Cerebral Ischemic

Borneol, a natural product in the Asteraceae family, is widely used as an upper ushering drug for various brain diseases in many Chinese herbal formulae. The blood-brain barrier (BBB) plays an essential role in maintaining a stable homeostatic environment, while BBB destruction and the increasing BBB permeability are common pathological processes in many serious central nervous system (CNS) diseases, which is especially an essential pathological basis of cerebral ischemic injury. Here, we aimed to conduct a systematic review to assess preclinical evidence of borneol for experimental ischemic stroke as well as investigate in the possible neuroprotective mechanisms, which mainly focused on regulating the permeability of BBB. Seven databases were searched from their inception to July 2018. The studies of borneol for ischemic stroke in animal models were included. RevMan 5.3 was applied for data analysis. Fifteen studies investigated the effects of borneol in experimental ischemic stroke involving 308 animals were ultimately identified. The present study showed that the administration of borneol exerted a significant decrease of BBB permeability during cerebral ischemic injury according to brain Evans blue content and brain water content compared with controls (P<0.01). In addition, borneol could improve neurological function scores (NFS) and cerebral infarction area. Thus, borneol may be a promising neuroprotective agent for cerebral ischemic injury, largely through alleviating the BBB disruption, reducing oxidative reactions, inhibiting the occurrence of inflammation, inhibiting apoptosis, and improving the activity of lactate dehydrogenase (LDH) as well as P-glycoprotein (P-GP) and NO signaling pathway.

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Photodynamic Opening of the Blood–Brain Barrier Using Different Photosensitizers in Mice

Applied Sciences ◽

10.3390/app10010033 ◽

2019 ◽

Vol 10 (1) ◽

pp. 33 ◽

Cited By ~ 1

Author(s):

Oxana Semyachkina-Glushkovskaya ◽

Ekaterina Borisova ◽

Vanya Mantareva ◽

Ivan Angelov ◽

Ivelina Eneva ◽

...

Keyword(s):

Tight Junction ◽

Blood Brain Barrier ◽

Confocal Imaging ◽

Brain Barrier ◽

Zinc Phthalocyanine ◽

Brain Diseases ◽

Blood Brain ◽

Age Related ◽

Dextran 70 ◽

The Brain

In a series of previous studies, we demonstrated that the photodynamic therapy (PDT), as a widely used tool for treatment of glioblastoma multiforme (GBM), also site-specifically opens the blood–brain barrier (BBB) in PDT-dose and age-related manner via reversible disorganization of the tight junction machinery. To develop the effective protocol of PDT-opening of the BBB, here we answer the question of what kind of photosensitizer (PS) is the most effective for the BBB opening. We studied the PDT-opening of the BBB in healthy mice using commercial photosensitizers (PSs) such as 5-aminolevulenic acid (5-ALA), aluminum phthalocyanine disulfonate (AlPcS), zinc phthalocyanine (ZnPc) and new synthetized PSs such as galactose functionalized ZnPc (GalZnPc). The spectrofluorimetric assay of Evans Blue albumin complex (EBAC) leakage and 3-D confocal imaging of FITC-dextran 70 kDa (FITCD) extravasation clearly shows a revisable and dose depended PDT-opening of the BBB to EBAC and FITCD associated with a decrease in presence of tight junction (TJ) in the vascular endothelium. The PDT effects on the BBB permeability, TJ expression and the fluorescent signal from the brain tissues are more pronounced in PDT-GalZnPc vs. PDT-5-ALA/AlPcS/ZnPc. These pre-clinical data are the first important informative platform for an optimization of the PDT protocol in the light of new knowledge about PDT-opening of the BBB for drug brain delivery and for the therapy of brain diseases.

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TRA2A-induced upregulation of LINC00662 regulates blood-brain barrier permeability by affecting ELK4 mRNA stability in Alzheimer's microenvironment

10.21203/rs.2.17596/v2 ◽

2019 ◽

Author(s):

Qianshuo Liu ◽

Lu Zhu ◽

Xiaobai Liu ◽

Jian Zheng ◽

Yunhui Liu ◽

...

Keyword(s):

Tight Junction ◽

Blood Brain Barrier ◽

Rna Binding ◽

Rna Binding Proteins ◽

Brain Barrier ◽

Blood Brain ◽

Bbb Permeability ◽

Novel Target ◽

Related Proteins

Abstract The blood-brain barrier (BBB) plays a pivotal role in maintenance and regulation of the neural microenvironment. The occurrence of BBB disruption is the pathological change of early Alzheimer’s disease (AD). RNA-binding proteins and long non-coding RNAs are involved in the regulation of BBB permeability. Our study was performed to demonstrate TRA2A/LINC00662/ELK4 axis in regulating BBB permeability in AD microenvironment. In Aβ1-42-incubated microvascular endothelial cells (ECs) of BBB model in vitro, TRA2A and LINC00662 were enriched. TRA2A increased the stability of LINC00662 by binding with it. The knockdown of either TRA2A or LINC00662 decreased the BBB permeability via upregulating the expressions of tight junction-related proteins. ELK4 was lower expressed in BBB model in vitro in AD microenvironment. LINC00662 mediated the degradation of ELK4 mRNA by SMD pathway. The downregulated ELK4 increased the permeability of BTB by increasing the tight junction-related proteins expressions. TRA2A/LINC00662/ELK4 axis plays a crucial role in the regulation of BBB permeability in AD microenvironment, which may provide a novel target for the therapy of AD.

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The role of hypoxia-inducible factor-1α, aquaporin-4, and matrix metalloproteinase-9 in blood-brain barrier disruption and brain edema after traumatic brain injury

Journal of Neurosurgery ◽

10.3171/2010.6.jns10207 ◽

2011 ◽

Vol 114 (1) ◽

pp. 92-101 ◽

Cited By ~ 172

Author(s):

Tetsuhiro Higashida ◽

Christian W. Kreipke ◽

José A. Rafols ◽

Changya Peng ◽

Steven Schafer ◽

...

Keyword(s):

Tight Junction ◽

Brain Edema ◽

Blood Brain Barrier ◽

Hypoxia Inducible Factor ◽

Brain Barrier ◽

Tight Junction Proteins ◽

Edema Formation ◽

Blood Brain ◽

Bbb Permeability ◽

Junction Proteins

Object The present study investigated the role of hypoxia-inducible factor-1α (HIF-1α), aquaporin-4 (AQP-4), and matrix metalloproteinase-9 (MMP-9) in blood-brain barrier (BBB) permeability alterations and brain edema formation in a rodent traumatic brain injury (TBI) model. Methods The brains of adult male Sprague-Dawley rats (400–425 g) were injured using the Marmarou closed-head force impact model. Anti–AQP-4 antibody, minocycline (an inhibitor of MMP-9), or 2-methoxyestradiol (2ME2, an inhibitor of HIF-1α), was administered intravenously 30 minutes after injury. The rats were killed 24 hours after injury and their brains were examined for protein expression, BBB permeability, and brain edema. Expression of HIF-1α, AQP-4, and MMP-9 as well as expression of the vascular basal lamina protein (laminin) and tight junction proteins (zona occludens-1 and occludin) was determined by Western blotting. Blood-brain barrier disruption was assessed by FITC-dextran extravasation, and brain edema was measured by the brain water content. Results Significant (p < 0.05) edema and BBB extravasations were observed following TBI induction. Compared with sham-operated controls, the injured animals were found to have significantly (p < 0.05) enhanced expression of HIF-1α, AQP-4, and MMP-9, in addition to reduced amounts (p < 0.05) of laminin and tight junction proteins. Edema was significantly (p < 0.01) decreased after inhibition of AQP-4, MMP-9, or HIF-1α. While BBB permeability was significantly (p < 0.01) ameliorated after inhibition of either HIF-1α or MMP-9, it was not affected following inhibition of AQP-4. Inhibition of MMP reversed the loss of laminin (p < 0.01). Finally, while inhibition of HIF-1α significantly (p < 0.05) suppressed the expression of AQP-4 and MMP-9, such inhibition significantly (p < 0.05) increased the expression of laminin and tight junction proteins. Conclusions The data support the notion that HIF-1α plays a role in brain edema formation and BBB disruption via a molecular pathway cascade involving AQP-4 and MMP-9. Pharmacological blockade of this pathway in patients with TBI may provide a novel therapeutic strategy.

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TRA2A-induced upregulation of LINC00662 regulates blood-brain barrier permeability by affecting ELK4 mRNA stability in Alzheimer's microenvironment

10.21203/rs.2.17596/v1 ◽

2019 ◽

Author(s):

Qianshuo Liu ◽

Lu Zhu ◽

Xiaobai Liu ◽

Jian Zheng ◽

Yunhui Liu ◽

...

Keyword(s):

Tight Junction ◽

Blood Brain Barrier ◽

Rna Binding ◽

Rna Binding Proteins ◽

Brain Barrier ◽

Blood Brain ◽

Bbb Permeability ◽

Novel Target ◽

Related Proteins

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Protein Nanoparticle-Related Osmotic Pressure Modifies Nonselective Permeability of the Blood–Brain Barrier by Increasing Membrane Fluidity

International Journal of Nanomedicine ◽

10.2147/ijn.s291286 ◽

2021 ◽

Vol Volume 16 ◽

pp. 1663-1680

Author(s):

Chen Li ◽

LinLin Chen ◽

YuanYuan Wang ◽

TingTing Wang ◽

Dong Di ◽

...

Keyword(s):

Osmotic Pressure ◽

Membrane Fluidity ◽

Blood Brain Barrier ◽

Brain Barrier ◽

Blood Brain

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RhoA/ROCK-2 Pathway Inhibition and Tight Junction Protein Upregulation by Catalpol Suppresses Lipopolysaccaride-Induced Disruption of Blood-Brain Barrier Permeability

Molecules ◽

10.3390/molecules23092371 ◽

2018 ◽

Vol 23 (9) ◽

pp. 2371 ◽

Cited By ~ 14

Author(s):

Shan Feng ◽

Li Zou ◽

Hongjin Wang ◽

Ran He ◽

Ke Liu ◽

...

Keyword(s):

Tight Junction ◽

Signaling Pathway ◽

Tight Junctions ◽

Blood Brain Barrier ◽

Tight Junction Protein ◽

Brain Barrier ◽

Endothelin 1 ◽

Blood Brain ◽

Junction Protein ◽

Bbb Permeability

Lipopolysaccaride (LPS) directly or indirectly injures brain microvascular endothelial cells (BMECs) and damages the intercellular tight junction that gives rise to altered blood-brain barrier (BBB) permeability. Catalpol plays a protective role in LPS-induced injury, but whether catalpol protects against LPS-caused damage of BBB permeability and the underlying mechanism remain to be delineated. Prophylactic protection with catalpol (5 mg/kg, i.v.) consecutively for three days reversed the LPS-induced damage of BBB by decreased Evans Blue (EB) leakage and restored tight junctions in C57 mice. Besides, catalpol co-administrated with LPS increased BMECs survival, decreased their endothelin-1, TNF-Α and IL-6 secretion, improved transmembrane electrical resistance in a time-dependent manner, and in addition increased the fluorescein sodium permeability coefficient of BMECs. Also, transmission electron microscopy showed catalpol protective effects on tight junctions. Fluorescence staining displayed that catalpol reversed the rearrangement of the cytoskeleton protein F-actin and upregulated the tight junction protein of claudin-5 and ZO-1, which have been further demonstrated by the mRNA and protein expression levels of ZO-1, ZO-2, ZO-3, claudin-5, and occludin. Moreover, catalpol concurrently downregulated the mRNA and protein levels of RhoA, and ROCK2, the critical proteins in the RhoA/ROCK2 signaling pathway. This study thus indicated that catalpol, via inhibition of the RhoA/ROCK2 signaling pathway, reverses the disaggregation of cytoskeleton actin in BMECs and prevents down-regulation of junctional proteins, such as claudin-5, occludin, and ZO-1, and decreases endothelin-1 and inflammatory cytokine secretion, eventually alleviating the increase in LPS-induced BBB permeability.

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Transforming Growth Factor-β Signaling Alters Substrate Permeability and Tight Junction Protein Expression at the Blood-Brain Barrier during Inflammatory Pain

Journal of Cerebral Blood Flow & Metabolism ◽

10.1038/jcbfm.2009.32 ◽

2009 ◽

Vol 29 (6) ◽

pp. 1084-1098 ◽

Cited By ~ 80

Author(s):

Patrick T Ronaldson ◽

Kristin M DeMarco ◽

Lucy Sanchez-Covarrubias ◽

Christine M Solinsky ◽

Thomas P Davis

Keyword(s):

Growth Factor ◽

Protein Expression ◽

Tight Junction ◽

Blood Brain Barrier ◽

Inflammatory Pain ◽

Transforming Growth Factor ◽

Brain Barrier ◽

Functional Integrity ◽

Blood Brain ◽

Bbb Permeability

Our laboratory has shown that peripheral inflammatory pain induced by λ-carrageenan (CIP) can increase blood-brain barrier (BBB) permeability and alter tight junction (TJ) protein expression leading to changes in BBB functional integrity. However, the intracellular signaling mechanisms involved in this pathophysiologic response have not been elucidated. Transforming growth factor (TGF)-β signaling pathways are known to regulate vascular integrity and permeability. Therefore, we examined the function of TGF-β signaling at the BBB in rats subjected to CIP. During CIP, serum TGF-β1 and protein expression of the TGF-β receptor activin receptor-like kinase-5 (ALK5) were reduced. Brain permeability to 14C-sucrose was increased and expression of TJ proteins (i.e., claudin-5, occludin, zonula occluden (ZO-1)) were also altered after 3 h CIP. Pharmacological inhibition of ALK5 with the selective inhibitor SB431542 further enhanced brain uptake of 14C-sucrose, increased TJ protein expression (i.e., claudin-3, claudin-5, occludin, ZO-1), and decreased nuclear expression of TGF-β/ALK5 signaling molecules (i.e., Smad2, Smad3), which suggests a role for TGF-β/ALK5 signaling in the regulation of BBB integrity. Interestingly, administration of exogenous TGF-β before CIP activated the TGF-β/ALK5 pathway and reduced BBB permeability to 14C-sucrose. Taken together, our data show that TGF-β/ALK5 signaling is, in part, involved in the regulation of BBB functional integrity.

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TRA2A-induced upregulation of LINC00662 regulates blood-brain barrier permeability by affecting ELK4 mRNA stability in Alzheimer’s microenvironment

10.1101/848408 ◽

2019 ◽

Author(s):

Qianshuo Liu ◽

Lu Zhu ◽

Xiaobai Liu ◽

Jian Zheng ◽

Yunhui Liu ◽

...

Keyword(s):

Tight Junction ◽

Blood Brain Barrier ◽

Rna Binding ◽

Rna Binding Proteins ◽

Brain Barrier ◽

Blood Brain ◽

Bbb Permeability ◽

Early Alzheimer’S Disease ◽

Related Proteins

AbstractThe blood-brain barrier (BBB) has an important significance in maintenance and regulation of the neural microenvironment. The occurrence of BBB disruption is the pathological change of early Alzheimer’s disease (AD). RNA-binding proteins and long non-coding RNAs are closely related to the regulation of BBB permeability. Our study was performed to demonstrate TRA2A/LINC00662/ELK4 axis that regulates BBB permeability in AD microenvironment. In Aβ1-42-incubated microvascular endothelial cells (ECs) of BBB model in vitro, TRA2A and LINC00662 were enriched. TRA2A increased the stability of LINC00662 by binding with it. The knockdown of either TRA2A or LINC00662 decreased the BBB permeability via upregulating the levels of tight junction-related proteins. ELK4 was downregulated in BBB model in vitro in AD microenvironment. LINC00662 mediated the degradation of ELK4 mRNA by SMD pathway. The downregulated ELK4 increased the permeability of BTB by inducing the tight junction-related proteins. TRA2A/LINC00662/ELK4 axis is important in the regulation of BBB permeability in AD microenvironment, which would be a new molecular target for AD treatment.

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