scholarly journals Mfsd2b and Spns2 are essential for maintenance of blood vessels during development and protection of anaphylaxis

2021 ◽  
Author(s):  
Thanh Nha Uyen Le ◽  
Toan Q Nguyen ◽  
Yen Thi Kim Nguyen ◽  
Clarissa Kai Hui Tan ◽  
Farhana Tukijan ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Blood Vessel ◽  
Cell Types ◽  
Lipid Mediator ◽  
Tight Junction Proteins ◽  
Severe Hemorrhage ◽  
Sphingosine 1 Phosphate ◽  
Vessel Integrity ◽  
Maximal Reduction ◽  
Junction Proteins

Sphingosine-1-phosphate (S1P) is a potent lipid mediator that is secreted by several cell types to induce signaling. We recently showed that Mfsd2b is an S1P transporter from hematopoietic cells, which contributes approximately 50% plasma S1P. To further determine the sources of plasma S1P, here, we report the characterizations of compound deletions of Mfsd2b and Spns2, another S1P transporter from endothelial cells. Global deletion of Mfsd2b and Spns2 (gDKO) resulted in embryonic lethality between E13.5 and E14.5 with severe hemorrhage that largely recapitulated the phenotypes from global S1P1 knockout mice, indicating that together with Mfsd2b, Spns2 also provides embryonic source of S1P for S1P1 stimulation. The hemorrhagic phenotypes in gDKO embryos were accompanied by increased angiogenesis and defects of tight junction proteins, indicating that S1P from Mfsd2b and Spns2 is essential for blood vessel integrity and maturation. The various sources of S1P in postnatal stages are yet to be fully understood. Postnatal ablation of S1P synthesis enzymes using Mx1Cre shows that Mx1Cre-sensitive cells provide most of plasma S1P. Interestingly, we showed that compound postnatal deletion of Mfsd2b and Spns2 using Mx1Cre (ctDKO-Mx1Cre) resulted in maximal reduction of 80% plasma S1P. Thus, a small amount of plasma S1P is supplied from other sources independent of Mfsd2b and Spns2. Nevertheless, the vasculature in the lung of ctDKO-Mx1Cre mice was compromised. Furthermore, ctDKO-Mx1Cre mice also exhibited severe susceptibility to anaphylaxis, indicating that S1P from Mfsd2b and Spns2 is indispensable during vascular stress. Together, our results show that Mfsd2b and Spns2 provide a critical source of S1P for embryonic development and they also provide a majority of plasma S1P for vascular homeostasis.

scholarly journals Matrix Metalloproteinase Activity in Infections by an Encephalitic Virus, Mouse Adenovirus Type 1

2017 ◽  
Vol 91 (6) ◽  
Author(s):  
Shanna L. Ashley ◽  
Carla D. Pretto ◽  
Matthew T. Stier ◽  
Padma Kadiyala ◽  
Luiza Castro-Jorge ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tight Junction ◽  
Ex Vivo ◽  
Adenovirus Type ◽  
Cell Types ◽  
Tight Junction Proteins ◽  
Mock Infection ◽  
Junction Proteins

ABSTRACT Mouse adenovirus type 1 (MAV-1) infection causes encephalitis in susceptible strains of mice and alters the permeability of infected brains to small molecules, which indicates disruption of the blood-brain barrier (BBB). Under pathological conditions, matrix metalloproteinases (MMPs) can disrupt the BBB through their proteolytic activity on basement membrane and tight junction proteins. We examined whether MAV-1 infection alters MMP activity in vivo and in vitro. Infected MAV-1-susceptible SJL mice had higher MMP2 and MMP9 activity in brains, measured by gelatin zymography, than mock-infected mice. Infected MAV-1-resistant BALB/c mice had MMP activity levels equivalent to those in mock infection. Primary SJL mouse brain endothelial cells (a target of MAV-1 in vivo) infected ex vivo with MAV-1 had no difference in activities of secreted MMP2 and MMP9 from mock cells. We show for the first time that astrocytes and microglia are also infected in vivo by MAV-1. Infected mixed primary cultures of astrocytes and microglia had higher levels of MMP2 and MMP9 activity than mock-infected cells. These results indicate that increased MMP activity in the brains of MAV-1-infected susceptible mice may be due to MMP activity produced by endothelial cells, astrocytes, and microglia, which in turn may contribute to BBB disruption and encephalitis in susceptible mice. IMPORTANCE RNA and DNA viruses can cause encephalitis; in some cases, this is accompanied by MMP-mediated disruption of the BBB. Activated MMPs degrade extracellular matrix and cleave tight-junction proteins and cytokines, modulating their functions. MAV-1 infection of susceptible mice is a tractable small-animal model for encephalitis, and the virus causes disruption of the BBB. We showed that MAV-1 infection increases enzymatic activity of two key MMPs known to be secreted and activated in neuroinflammation, MMP2 and MMP9, in brains of susceptible mice. MAV-1 infects endothelial cells, astrocytes, and microglia, cell types in the neurovascular unit that can secrete MMPs. Ex vivo MAV-1 infection of these cell types caused higher MMP activity than mock infection, suggesting that they may contribute to the higher MMP activity seen in vivo. To our knowledge, this provides the first evidence of an encephalitic DNA virus in its natural host causing increased MMP activity in brains.

scholarly journals Peroxiredoxin 6 is required for blood vessel integrity in wounded skin

2007 ◽  
Vol 179 (4) ◽  
pp. 747-760 ◽  
Author(s):  
Angelika Kümin ◽  
Matthias Schäfer ◽  
Nikolas Epp ◽  
Philippe Bugnon ◽  
Christiane Born-Berclaz ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Wound Healing ◽  
Endothelial Cells ◽  
Ultrastructural Level ◽  
Peroxiredoxin 6 ◽  
Severe Hemorrhage ◽  
Vessel Integrity ◽  
Knockout Animals

Peroxiredoxin 6 (Prdx6) is a cytoprotective enzyme with largely unknown in vivo functions. Here, we use Prdx6 knockout mice to determine its role in UV protection and wound healing. UV-mediated keratinocyte apoptosis is enhanced in Prdx6-deficient mice. Upon skin injury, we observe a severe hemorrhage in the granulation tissue of knockout animals, which correlates with the extent of oxidative stress. At the ultrastructural level endothelial cells appear highly damaged, and their rate of apoptosis is enhanced. Knock-down of Prdx6 in cultured endothelial cells also increases their susceptibility to oxidative stress, thus confirming the sensitivity of this cell type to loss of Prdx6. Wound healing studies in bone marrow chimeric mice demonstrate that Prdx6-deficient inflammatory and endothelial cells contribute to the hemorrhage phenotype. These results provide insight into the cross-talk between hematopoietic and resident cells at the wound site and the role of reactive oxygen species in this interplay.

scholarly journals Heterotypic inter-GPCR ß-arrestin coupling regulates lymphatic endothelial junctional architecture in murine lymph nodes

2018 ◽  
Author(s):  
Yu Hisano ◽  
Mari Kono ◽  
Eric Engelbrecht ◽  
Koki Kawakami ◽  
Keisuke Yanagida ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Lymph Nodes ◽  
Cross Talk ◽  
Transcriptional Activation ◽  
Endothelial Permeability ◽  
Lipid Mediator ◽  
Protein Signaling ◽  
A Genome ◽  
Sphingosine 1 Phosphate ◽  
A Site

AbstractLysophosphatidic acid (LPA) and sphingosine 1-phosphate (S1P) activate G protein-coupled receptors (GPCRs) to regulate key pathobiological processes. Here we report a novel lipid mediator GPCR cross-talk mechanism that modulates lymphatic endothelial junctional architecture in lymph nodes. LPAR1 was identified as an inducer of S1PR1/ ß-arrestin coupling from a genome-wide CRISPR/ Cas9 transcriptional activation screen. LPAR1 activation induced S1PR1 ß-arrestin recruitment while suppressing Gαi protein signaling. Lymphatic endothelial cells from cortical and medullary sinuses of lymph nodes which express LPAR1 and S1PR1, exhibit porous junctional architecture and constitutive S1PR1 coupling to ß-arrestin which was suppressed by the LPAR1 antagonist AM095. In endothelial cells, LPAR1-activation increased trans-endothelial permeability and junctional remodeling from zipper-like structures to puncta of adhesion plaques that terminate at actin-rich stress fibers with abundant intercellular gaps. Cross-talk between LPA and S1P receptors regulates complex junctional architecture of lymphatic sinus endothelial cells, a site of high lymphocyte traffic and lymph flow.

scholarly journals Interleukin-34 Restores Blood–Brain Barrier Integrity by Upregulating Tight Junction Proteins in Endothelial Cells

PLoS ONE ◽  
2014 ◽  
Vol 9 (12) ◽  
pp. e115981 ◽  
Author(s):  
Shijie Jin ◽  
Yoshifumi Sonobe ◽  
Jun Kawanokuchi ◽  
Hiroshi Horiuchi ◽  
Yi Cheng ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tight Junction ◽  
Blood Brain Barrier ◽  
Brain Barrier ◽  
Tight Junction Proteins ◽  
Barrier Integrity ◽  
Blood Brain ◽  
Blood Brain Barrier Integrity ◽  
Junction Proteins

scholarly journals Decursin Inhibits VEGF-Mediated Inner Blood—Retinal Barrier Breakdown by Suppression of VEGFR-2 Activation

2009 ◽  
Vol 29 (9) ◽  
pp. 1559-1567 ◽  
Author(s):  
Jin Hyoung Kim ◽  
Jeong Hun Kim ◽  
You Mie Lee ◽  
Eun-Mi Ahn ◽  
Kyu-Won Kim ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Tight Junction ◽  
Vision Loss ◽  
Retinal Vessels ◽  
Tight Junction Proteins ◽  
Blood Retinal Barrier ◽  
Retinal Endothelial Cells ◽  
Extracellular Signal ◽  
Brb Breakdown ◽  
Junction Proteins

The blood—retinal barrier (BRB) is essential for the normal structural and functional integrity of the retina, whose breakdown could cause the serious vision loss. Vascular endothelial growth factor (VEGF), as a permeable factor, induces alteration of tight junction proteins to result in BRB breakdown. Herein, we demonstrated that decursin inhibits VEGF-mediated inner BRB breakdown through suppression of VEGFR-2 signaling pathway. In retinal endothelial cells, decursin inhibited VEGF-mediated hyperpermeability. Decursin prevented VEGF-mediated loss of tight junction proteins including zonula occludens-1 (ZO-1), ZO-2, and occludin in retinal endothelial cells, which was also supported by restoration of tight junction proteins in intercellular junction. In addition, decursin significantly inhibited VEGF-mediated vascular leakage from retinal vessels, which was accompanied by prevention of loss of tight junction proteins in retinal vessels. Decursin significantly suppressed VEGF-induced VEGFR-2 phosphrylation that consequently led to inhibition of extracellular signal-regulated kinase (ERK) 1/2 activation. Moreover, decursin induced no cytotoxicity to retinal endothelial cells and no retinal toxicity under therapeutic concentrations. Therefore, our results suggest that decursin prevents VEGF-mediated BRB breakdown through blocking of loss of tight junction proteins, which might be regulated by suppression of VEGFR-2 activation. As a novel inhibitor to BRB breakdown, decursin could be applied to variable retinopathies with BRB breakdown.

scholarly journals Methylglyoxal-Induced Dysfunction in Brain Endothelial Cells via the Suppression of Akt/HIF-1α Pathway and Activation of Mitophagy Associated with Increased Reactive Oxygen Species

Antioxidants ◽  
2020 ◽  
Vol 9 (9) ◽  
pp. 820 ◽  
Author(s):  
Donghyun Kim ◽  
Kyeong-A Kim ◽  
Jeong-Hyeon Kim ◽  
Eun-Hye Kim ◽  
Ok-Nam Bae
Keyword(s):  
Oxidative Stress ◽  
Reactive Oxygen Species ◽  
Endothelial Cells ◽  
Tight Junction ◽  
Reactive Oxygen ◽  
Mitochondrial Damage ◽  
Oxygen Species ◽  
Brain Endothelial Cells ◽  
Tight Junction Proteins ◽  
Junction Proteins

Methylglyoxal (MG) is a dicarbonyl compound, the level of which is increased in the blood of diabetes patients. MG is reported to be involved in the development of cerebrovascular complications in diabetes, but the exact mechanisms need to be elucidated. Here, we investigated the possible roles of oxidative stress and mitophagy in MG-induced functional damage in brain endothelial cells (ECs). Treatment of MG significantly altered metabolic stress as observed by the oxygen-consumption rate and barrier-integrity as found in impaired trans-endothelial electrical resistance in brain ECs. The accumulation of MG adducts and the disturbance of the glyoxalase system, which are major detoxification enzymes of MG, occurred concurrently. Reactive oxygen species (ROS)-triggered oxidative damage was observed with increased mitochondrial ROS production and the suppressed Akt/hypoxia-inducible factor 1 alpha (HIF-1α) pathway. Along with the disturbance of mitochondrial bioenergetic function, parkin-1-mediated mitophagy was increased by MG. Treatment of N-acetyl cysteine significantly reversed mitochondrial damage and mitophagy. Notably, MG induced dysregulation of tight junction proteins including occludin, claudin-5, and zonula occluden-1 in brain ECs. Here, we propose that diabetic metabolite MG-associated oxidative stress may contribute to mitochondrial damage and autophagy in brain ECs, resulting in the dysregulation of tight junction proteins and the impairment of permeability.

Abstract 3754: Homocysteine Induces Alternations Of Tight Junction Proteins In Brain Endothelial Cells.

Stroke ◽  
2012 ◽  
Vol 43 (suppl_1) ◽  
Author(s):  
Neetu Tyagi ◽  
Natia Qipshidze ◽  
Srikanth Givvimani ◽  
Paras K Mishra ◽  
David Lominadze ◽  
...  
Keyword(s):  
Oxidative Stress ◽  
Endothelial Cells ◽  
Tight Junction ◽  
Kinase Inhibitors ◽  
Mitogen Activated Protein Kinase ◽  
High Dose ◽  
Tight Junction Proteins ◽  
Filamentous Actin ◽  
Mek Kinase ◽  
Junction Proteins

Hyperhomocysteinmia (HHcy) is associated with neurological disorders (Stroke, Alzheimer, Parkinson etc) and causes blood brain barrier (BBB) dysfunction. We previously showed that an elevated level of homocysteine (Hcy) increased formation of filamentous actin and enhanced endothelial layer permeability. In the present work we tested the hypothesis that Hcy induces oxidative stress and binding to endothelial cells (ECs) alters expression of endothelial tight junction proteins (TJP). In this study mouse brain microvascular endothelial cells (bEND3) were grown in gold plated chambers of an electrical cell-substrate impedance system, 8-well chambered. Confluent bEND3 were treated with different doses of Hcy with mitogen-activated protein kinase (MEK) kinase inhibitors (PD98059 or U0126) or H 2 O 2 (oxidant), or medium alone for 24 h. Reactive oxygen species (ROS) was detected using DCFH-DA assay. Hcy induced a dose-dependent decrease in EC junction integrity as determined by transendothelial electrical resistance (TEER). Our results show that high dose of Hcy induces oxidative stress, which cause down regulation of the TJPs contents occludin, zona occluden-1 (ZO-1), and zona occluden-2 (ZO-2) in bEND3s. Hcy-induced decreases in contents of the TJPs were blocked by PD98059, U0126. While BQ788 inhibited endothelin-1-induced decrease in TEER, it did not affect Hcy-induced decrease in TEER. These data suggest that Hcy increases EC layer permeability via the MEK kinase signaling pathway by affecting TJPs, which are bound to actin filaments. Therefore, increased binding of Hcy with ECs during cerebo-vascular diseases may increase microvascular permeability by altering the content and possibly subcellular localization of endothelial TJPs.

MMP-2 and MMP-9 Secreted by Leukemic Cells Increase the Permeability of Blood-Brain Barrier by Disrupting Tight Junction Proteins In Central Nervous System Leukemia

Blood ◽  
2010 ◽  
Vol 116 (21) ◽  
pp. 2694-2694
Author(s):  
Sa-ran Feng ◽  
Zi-Xing Chen ◽  
Jian-nong Cen ◽  
Hong-jie Shen ◽  
Li Yao ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Endothelial Cells ◽  
Nervous System ◽  
Acute Leukemia ◽  
Tight Junction ◽  
Blood Brain Barrier ◽  
Leukemia Cell ◽  
Leukemic Cells ◽  
Tight Junction Proteins ◽  
Junction Proteins

Abstract Abstract 2694 Recurrence of acute leukemia (AL) in the central nervous system (CNS) confers a poor prognosis. However, little is known about the the underlying mechanisms of leukemic cell infiltration into the CNS. The blood brain barrier (BBB) makes CNS become a refugee to leukemic cells and serves as a resource of cells that seed extraneural sites. Tight junction in brain microvessel endothelial cells (HMECs) constituted by tight junction proteins is an important structure of BBB. Except the well known role of degrading extracellular matrix in metastasis of cancer cells, here we identify matrix metalloproteinase 2 (MMP-2) and MMP-9 secreted by leukemic cells are also associated with BBB opening by degrading tight junction proteins. We have successfully established an animal model of CNS leukemia by using a highly invasive human acute monocytic leukemia cell line SHI-1 in nude mice. Multiple organs including skull and brain were sectioned and determined histopathologically for leukemia cell infiltration. The fact that the down- regulation of ZO-1, Claun-5 and Occludin accompanied with up-regulation of MMP-2 and MMP-9 was correlated with BBB breakdown in mice with CNS leukemia was found when examined by laser scanning fluorescence confocal microscopy and gelatin in situ zymography. The treatment with MMP-inhibitor GM6001 could significantly reverse these changes in tight junction proteins. In an in vitro monolayer BBB model made by human encephalo-microvessel endothelial cells and matreil gel, MMP-2 and MMP-9 specifically down-regulated ZO-1, Claun-5 and Occludin. Knock-down or inhibition of MMP-2 and MMP-9 expression protected ZO-1, Claun-5 and occludin from degradation and alleviated the permeability of BBB. Our findings suggest that the degradation of tight junction proteins ZO-1, Claun-5 and Occludin by MMP-2 and MMP-9 secreted by leukemic cells constitutes an important mechanism in BBB breakdown in CNS leukemia. These studies provide a potent evidence for future pharmacological treatment to inhibit the CNS involvement in acute leukemia. Disclosures: No relevant conflicts of interest to declare.

Sign in / Sign up

Export Citation Format

Share Document