scholarly journals LPS Induces Occludin Dysregulation in Cerebral Microvascular Endothelial Cells via MAPK Signaling and Augmenting MMP-2 Levels

2015 ◽  
Vol 2015 ◽  
pp. 1-9 ◽  
Author(s):  
Lan-hui Qin ◽  
Wen Huang ◽  
Xue-an Mo ◽  
Yan-lan Chen ◽  
Xiang-hong Wu
Keyword(s):  
Endothelial Cells ◽  
Central Nervous System Infection ◽  
Mapk Signaling ◽  
Microvascular Endothelial Cells ◽  
Enzyme Linked Immunosorbent Assay ◽  
Mrna Levels ◽  
Doxycycline Hyclate ◽  
Protein Levels ◽  
Cell Vitality ◽  
Microvascular Endothelial

Disrupted blood-brain barrier (BBB) integrity contributes to cerebral edema during central nervous system infection. The current study explored the mechanism of lipopolysaccharide- (LPS-) induced dysregulation of tight junction (TJ) proteins. Human cerebral microvascular endothelial cells (hCMEC/D3) were exposed to LPS, SB203580 (p38MAPK inhibitor), or SP600125 (JNK inhibitor), and cell vitality was determined by MTT assay. The proteins expressions of p38MAPK, JNK, and TJs (occludin and zonula occludens- (ZO-) 1) were determined by western blot. The mRNA levels of TJ components and MMP-2 were measured with quantitative real-time polymerase chain reaction (qRT-PCR), and MMP-2 protein levels were determined by enzyme-linked immunosorbent assay (ELISA). LPS, SB203580, and SP600125 under respective concentrations of 10, 7.69, or 0.22 µg/mL had no effects on cell vitality. Treatment with LPS decreased mRNA and protein levels of occludin and ZO-1 and enhanced p38MAPK and JNK phosphorylation and MMP-2 expression. These effects were attenuated by pretreatment with SB203580 or SP600125, but not in ZO-1 expression. Both doxycycline hyclate (a total MMP inhibitor) and SB-3CT (a specific MMP-2 inhibitor) partially attenuated the LPS-induced downregulation of occludin. These data suggest that MMP-2 overexpression and p38MAPK/JNK pathways are involved in the LPS-mediated alterations of occludin in hCMEC/D3; however, ZO-1 levels are not influenced by p38MAPK/JNK.

scholarly journals Bevacizumab Increases Endothelin-1 Production via Forkhead Box Protein O1 in Human Glomerular Microvascular Endothelial Cells In Vitro

2021 ◽  
Vol 2021 ◽  
pp. 1-8
Author(s):  
Satoru Nihei ◽  
Junichi Asaka ◽  
Hiroaki Takahashi ◽  
Kenzo Kudo
Keyword(s):  
Endothelial Cells ◽  
Molecular Mechanisms ◽  
Microvascular Endothelial Cells ◽  
Enzyme Linked Immunosorbent Assay ◽  
Endothelin 1 ◽  
Protein Levels ◽  
Forkhead Box ◽  
Phosphorylated Akt ◽  
Microvascular Endothelial

Molecular mechanisms underlying the nephrotoxicity associated with bevacizumab are unclear. Endothelin-1 (ET-1) is involved in podocyte injury and proteinuria, and its level increases in most cases of kidney disorders. Forkhead box protein O1 (FoxO1), a transcription factor, is a major determinant of ET-1 promoter activation and is regulated by protein kinase B (Akt) phosphorylation-dependent nuclear exclusion. We evaluated the effect of bevacizumab on ET-1 production in human glomerular microvascular endothelial cells (hGECs). We analyzed the changes in the mRNA and protein levels of ET-1 in hGECs treated with bevacizumab using real-time reverse transcription-polymerase chain reaction and enzyme-linked immunosorbent assay. Changes in the protein levels and phosphorylation status of Akt and FoxO1 in hGECs treated with bevacizumab were analyzed by western blotting. After cell lysis, FoxO1 protein was isolated from the cytoplasmic and nuclear fractions. We also investigated the effects of AS1842856 (a FoxO1 inhibitor) on bevacizumab-induced ET-1 production. Bevacizumab significantly and dose-dependently increased the mRNA and protein levels of ET-1 in hGECs ( p  < 0.05). Bevacizumab treatment also led to a decrease in phosphorylated Akt protein levels. Inhibition of Akt activity by LY294002 promoted ET-1 production. Bevacizumab also induced an increase in FoxO1 protein levels in the nucleus. Inhibition of FoxO1 activity by AS1842856 resulted in decreased ET-1 levels in bevacizumab-treated hGECs. ET-1 axis activation, Akt inactivation, and FoxO1 nuclear localization are the molecular mechanisms underlying bevacizumab-induced nephrotoxicity. Therefore, inhibition of renal ET-1 production could be a promising approach to protect against or treat bevacizumab-induced nephrotoxicity.

scholarly journals Endothelial CCR6 expression due to FLI1 deficiency contributes to vasculopathy associated with systemic sclerosis

2021 ◽  
Vol 23 (1) ◽  
Author(s):  
Tetsuya Ikawa ◽  
Takuya Miyagawa ◽  
Yuki Fukui ◽  
Satoshi Toyama ◽  
Jun Omatsu ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Systemic Sclerosis ◽  
Vascular Permeability ◽  
Dermal Fibroblasts ◽  
Microvascular Endothelial Cells ◽  
Clinical Samples ◽  
Mrna Levels ◽  
Angiogenic Activity ◽  
Microvascular Endothelial

Abstract Background We have recently demonstrated that serum CCL20 levels positively correlate with mean pulmonary arterial pressure in patients with systemic sclerosis (SSc). Considering a proangiogenic effect of CCL20 on endothelial cells via CCR6, the CCL20/CCR6 axis may contribute to the development of SSc vasculopathy. Therefore, we explored this hypothesis using clinical samples, cultured cells, and murine SSc models. Methods The expression levels of CCL20 and CCR6 in the skin, mRNA levels of target genes, and the binding of transcription factor FLI1 to the target gene promoter were evaluated by immunostaining, quantitative reverse transcription PCR, and chromatin immunoprecipitation, respectively. Vascular permeability was evaluated by Evans blue dye injection in bleomycin-treated mice. Angiogenic activity of endothelial cells was assessed by in vitro angiogenesis assay. Results CCL20 expression was significantly elevated in dermal fibroblasts of patients with early diffuse cutaneous SSc, while CCR6 was significantly up-regulated in dermal small vessels of SSc patients irrespective of disease subtypes and disease duration. In human dermal microvascular endothelial cells, FLI1 siRNA induced the expression of CCR6, but not CCL20, and FLI1 bound to the CCR6 promoter. Importantly, vascular permeability, a representative SSc-like vascular feature of bleomycin-treated mice, was attenuated by Ccr6 siRNA treatment, and CCR6 siRNA suppressed the angiogenic activity of human dermal microvascular endothelial cells assayed by in vitro tube formation. Conclusions The increased expression of endothelial CCR6 due to FLI1 deficiency may contribute to the development of SSc vasculopathy.

scholarly journals Age-related Beta-synuclein Alters the p53/Mdm2 Pathway and Induces the Apoptosis of Brain Microvascular Endothelial Cells In Vitro

2018 ◽  
Vol 27 (5) ◽  
pp. 796-813 ◽  
Author(s):  
Katrin Brockhaus ◽  
Michael R. R. Böhm ◽  
Harutyun Melkonyan ◽  
Solon Thanos
Keyword(s):  
Endothelial Cells ◽  
Neurodegenerative Diseases ◽  
Microvascular Endothelial Cells ◽  
Mrna Levels ◽  
Brain Microvascular Endothelial Cells ◽  
Age Related ◽  
Microvascular Endothelial ◽  
Dose Dependent

Increased β-synuclein (Sncb) expression has been described in the aging visual system. Sncb functions as the physiological antagonist of α-synuclein (Snca), which is involved in the development of neurodegenerative diseases, such as Parkinson’s and Alzheimer’s diseases. However, the exact function of Sncb remains unknown. The aim of this study was to elucidate the age-dependent role of Sncb in brain microvascular endothelial cells (BMECs). BMECs were isolated from the cortices of 5- to 9-d-old Sprague-Dawley rats and were cultured with different concentrations of recombinant Sncb (rSncb) up to 72 h resembling to some degree age-related as well as pathophysiological conditions. Viability, apoptosis, expression levels of Snca, and the members of phospholipase D2 (Pld2)/ p53/ Mouse double minute 2 homolog (Mdm2)/p19(Arf) pathway, response in RAC-alpha serine/threonine-protein kinase (Akt), and stress-mediating factors such as heme oxygenase (decycling) 1 (Hmox) and Nicotinamide adenine dinucleotide phosphate oxygenase 4 (Nox4) were examined. rSncb-induced effects were confirmed through Sncb small interfering RNA (siRNA) knockdown in BMECs. We demonstrated that the viability decreases, while the rate of apoptosis underly dose-dependent alterations. For example, apoptosis increases in BMECs following the treatment with higher dosed rSncb. Furthermore, we observed a decrease in Snca immunostaining and messenger RNA (mRNA) levels following the exposure to higher rScnb concentrations. Akt was shown to be downregulated and pAkt upregulated by this treatment, which was accompanied by a dose-independent increase in p19(Arf) levels and enhanced intracellular Mdm2 translocation in contrast to a dose-dependent p53 activation. Moreover, Pld2 activity was shown to be induced in rSncb-treated BMECs. The expression of Hmox and Nox4 after Sncb treatment was altered on BEMCs. The obtained results demonstrate dose-dependent effects of Sncb on BMECs in vitro. For example, the p53-mediated and Akt-independent apoptosis together with the stress-mediated response of BMECs related to exposure of higher SNCB concentrations may reflect the increase in Sncb with duration of culture as well as its impact on cell decay. Further studies, expanding on the role of Sncb, may help understand its role in the neurodegenerative diseases.

scholarly journals Cytokine profiles of cultured microvascular endothelial cells from the human intestine

Gut ◽  
1998 ◽  
Vol 42 (5) ◽  
pp. 635-642 ◽  
Author(s):  
E M Nilsen ◽  
F-E Johansen ◽  
F L Jahnsen ◽  
K E A Lundin ◽  
T Scholz ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Transforming Growth Factor ◽  
Umbilical Vein ◽  
Microvascular Endothelial Cells ◽  
Enzyme Linked Immunosorbent Assay ◽  
Microvascular Endothelium ◽  
Gm Csf ◽  
Cytokine Profiles ◽  
Tnf Α ◽  
Microvascular Endothelial

Background and aims—Cytokine production by endothelial cells has, for practical reasons, been chiefly studied in human umbilical vein endothelial cells (HUVEC) but, because tissue-specific differences apparently exist, the role of human intestinal microvascular endothelial cells (HIMEC) as a source of mucosal cytokines was also assessed.Methods—The expression of cytokine transcripts in HIMEC was screened by means of reverse transcription polymerase chain reaction (RT-PCR) and compared with cytokine profiles of HUVEC. Production of cytokines was investigated by bioassay and enzyme linked immunosorbent assay (ELISA).Results—In the basal unstimulated state, HIMEC and HUVEC cultures contained detectable mRNA for interleukin (IL)-3, IL-7, IL-8, IL-11, IL-14, IL-15, tumour necrosis factor (TNF)-α, transforming growth factor (TGF)-β, and granulocyte-macrophage colony stimulating factor (GM-CSF). However, message was undetectable for IL-2, IL-4, IL-5, IL-9, IL-10, IL-12p40, IL-13, and interferon (IFN)-γ in the resting as well as the stimulated state. Stimulation of HIMEC and HUVEC with recombinant human (rh) IL-1β or rhTNF-α induced cell associated bioactive IL-1α but not IL-1β, as well as enhanced secretion of both IL-6 and IL-8. Furthermore, transcript levels for GM-CSF and TNF-α were enhanced by rhIL-1β or rhTNF-α in both cell types. Supernatants from Th1-like or Th0-like gluten reactive intestinal T cell clones derived from patients with coeliac disease elicited cytokine profiles in both HIMEC and HUVEC similar to those revealed after rhIL-1β or rhTNF-α stimulation.Conclusions—These data demonstrate that the intestinal microvascular endothelium may contribute to the cytokine network of the intestinal mucosa with the ability to respond to locally generated cytokines and to produce potent inflammatory mediators.

scholarly journals Hypoxic proliferation requires EGFR-mediated ERK activation in human pulmonary microvascular endothelial cells

2017 ◽  
Vol 312 (5) ◽  
pp. L649-L656 ◽  
Author(s):  
Hilary A. White ◽  
Yi Jin ◽  
Louis G. Chicoine ◽  
Bernadette Chen ◽  
Yusen Liu ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Cellular Proliferation ◽  
Growth Factor Receptor ◽  
Viable Cell ◽  
Microvascular Endothelial Cells ◽  
Cell Numbers ◽  
Pulmonary Microvascular Endothelial Cells ◽  
Protein Levels ◽  
Microvascular Endothelial ◽  
Arginase Ii

We have previously shown that hypoxic proliferation of human pulmonary microvascular endothelial cells (hPMVECs) depends on epidermal growth factor receptor (EGFR) activation. To determine downstream signaling leading to proliferation, we tested the hypothesis that hypoxia-induced proliferation in hPMVECs would require EGFR-mediated activation of extracellular signal-regulated kinase (ERK) leading to arginase II induction. To test this hypothesis, hPMVECs were incubated in either normoxia (21% O2, 5% CO2) or hypoxia (1% O2, 5% CO2) and Western blotting was performed for EGFR, arginase II, phosphorylated-ERK (pERK), and total ERK (ERK). Hypoxia led to greater EGFR, pERK, and arginase II protein levels than did normoxia in hPMVECs. To examine the role of EGFR in these hypoxia-induced changes, hPMVECs were transfected with siRNA against EGFR or a scrambled siRNA and placed in hypoxia. Inhibition of EGFR using siRNA attenuated hypoxia-induced pERK and arginase II expression as well as the hypoxia-induced increase in viable cell numbers. hPMVECs were then treated with vehicle, an EGFR inhibitor (AG1478), or an ERK pathway inhibitor (U0126) and placed in hypoxia. Pharmacologic inhibition of EGFR significantly attenuated the hypoxia-induced increase in pERK level. Both AG1478 and U0126 also significantly attenuated the hypoxia-induced increase in viable hPMVECs numbers. hPMVECs were transfected with an adenoviral vector containing arginase II (AdArg2) and overexpression of arginase II rescued the U0126-mediated decrease in viable cell numbers in hypoxic hPMVECs. Our findings suggest that hypoxic activation of EGFR results in phosphorylation of ERK, which is required for hypoxic induction of arginase II and cellular proliferation.

scholarly journals Pro-BDNF Contributes to Hypoxia/Reoxygenation Injury in Myocardial Microvascular Endothelial Cells: Roles of Receptors p75NTR and Sortilin and Activation of JNK and Caspase 3

2018 ◽  
Vol 2018 ◽  
pp. 1-11 ◽  
Author(s):  
Fei Yu ◽  
Yuezhu Liu ◽  
Junmei Xu
Keyword(s):  
Endothelial Cells ◽  
Structure Formation ◽  
Caspase 3 ◽  
Terminal Deoxynucleotidyl Transferase ◽  
Microvascular Endothelial Cells ◽  
Tunel Staining ◽  
Protein Levels ◽  
Reoxygenation Injury ◽  
Microvascular Endothelial ◽  
Hypoxia Reoxygenation

The aim of this study was to identify the role of the precursor of the brain-derived neurotrophic factor (pro-BDNF) in myocardial hypoxia/reoxygenation injury (H/R) and to address the underlying mechanisms. For this purpose, myocardial microvascular endothelial cells (MMECs) exposed to a high concentration of glucose (30 mM) for 48 h were subjected to 4 h of hypoxia followed by 2 h of reoxygenation. Terminal deoxynucleotidyl transferase (TdT) dUTP nick-end labeling (TUNEL) staining and flow-cytometric analysis were performed to detect apoptosis. Cell scratch and capillary-like-structure formation assays were employed to evaluate cell function. The levels of apoptosis-related proteins were evaluated by Western blotting and immunofluorescence assays. Our results showed that H/R resulted in MMEC injury, as indicated by significant increases in TUNEL-positive cell numbers and a reduction in MMEC migration and in capillary-like-structure formation coupled with increased pro-BDNF protein expression. In addition, overexpression of pro-BDNF in MMECs via a viral vector led to increased pro-BDNF expression, and this upregulation induced apoptosis. Mechanistic experiments revealed that H/R did not influence BDNF, JNK, and caspase 3 expression, but upregulated pro-BDNF, p75NTR, sortilin, phospho-JNK, and cleaved caspase 3 protein levels. In contrast, neutralization of endogenous pro-BDNF with an antibody significantly attenuated H/R-induced upregulation of pro-BDNF, p75NTR, sortilin, p-JNK, and cleaved caspase 3 protein levels, indicating that p75NTR-sortilin signaling and activation of JNK and caspase 3 may be involved in these effects. In conclusion, H/R-induced injury may be mediated by pro-BDNF, at least in part through the regulation of p75NTR-sortilin signaling and activation of JNK and caspase 3.

scholarly journals Astragalus Polysaccharide Suppresses the Expression of Adhesion Molecules through the Regulation of the p38 MAPK Signaling Pathway in Human Cardiac Microvascular Endothelial Cells after Ischemia-Reperfusion Injury

2013 ◽  
Vol 2013 ◽  
pp. 1-8 ◽  
Author(s):  
Zhu Hai-Yan ◽  
Gao Yong-Hong ◽  
Wang Zhi-Yao ◽  
Xu Bing ◽  
Wu Ai-Ming ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Reperfusion Injury ◽  
P38 Mapk ◽  
Ischemia Reperfusion Injury ◽  
Ischemia Reperfusion ◽  
Mapk Signaling ◽  
Microvascular Endothelial Cells ◽  
Astragalus Polysaccharide ◽  
Microvascular Endothelial ◽  
Cardiac Microvascular Endothelial Cells

Astragalus polysaccharide is a major component of radix astragali, a vital qi-reinforcing herb medicine with favorable immune-regulating effects. In a previous animal experiment, we demonstrated that astragalus polysaccharide effectively alleviates ischemia-reperfusion injury (IRI) of cardiac muscle through the regulation of the inflammatory reactions. However, the relationship between this herb and the cohesion molecules on the cell surface remains controversial. In this study, human cardiac microvascular endothelial cells (HCMECs) were used to validate the protective effects of astragalus under an IRI scheme simulated through hypoxia/reoxygenation in vitro. The results indicated that astragalus polysaccharide inhibited the cohesion between HCMECs and polymorphonuclear leukocyte (PMN) during IRI through the downregulation of p38 MAPK signaling and the reduction of cohesive molecule expression in HCMECs.

scholarly journals Effects of ompA Deletion on Expression of Type 1 Fimbriae in Escherichia coli K1 Strain RS218 and on the Association of E. coli with Human Brain Microvascular Endothelial Cells

2006 ◽  
Vol 74 (10) ◽  
pp. 5609-5616 ◽  
Author(s):  
Ching-Hao Teng ◽  
Yi Xie ◽  
Sooan Shin ◽  
Francescopaolo Di Cello ◽  
Maneesh Paul-Satyaseela ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Endothelial Cells ◽  
Human Brain ◽  
Microvascular Endothelial Cells ◽  
Mrna Levels ◽  
Brain Microvascular Endothelial Cells ◽  
E Coli ◽  
Type 1 Fimbriae ◽  
Microvascular Endothelial

ABSTRACT We have previously shown that outer membrane protein A (OmpA) and type 1 fimbriae are the bacterial determinants involved in Escherichia coli K1 binding to human brain microvascular endothelial cells (HBMEC), which constitute the blood-brain barrier. In investigating the role of OmpA in E. coli K1 binding to HBMEC, we showed for the first time that ompA deletion decreased the expression of type 1 fimbriae in E. coli K1. Decreased expression of type 1 fimbriae in the ompA deletion mutant was largely the result of driving the fim promoter toward the type 1 fimbrial phase-OFF orientation. mRNA levels of fimB and fimE were found to be decreased with the OmpA mutant compared to the parent strain. Of interest, the ompA deletion further decreased the abilities of E. coli K1 to bind to and invade HBMEC under the conditions of fixing type 1 fimbria expression in the phase-ON or phase-OFF status. These findings suggest that the decreased ability of the OmpA mutant to interact with HBMEC is not entirely due to its decreased type 1 fimbrial expression and that OmpA and type 1 fimbriae facilitate the interaction of E. coli K1 with HBMEC at least in an additive manner.

scholarly journals Adrenomedullin increases the expression of calcitonin-like receptor and receptor activity modifying protein 2 mRNA in human microvascular endothelial cells

2006 ◽  
Vol 190 (2) ◽  
pp. 505-514 ◽  
Author(s):  
Nele Schwarz ◽  
Derek Renshaw ◽  
Supriya Kapas ◽  
Joy P Hinson
Keyword(s):  
Endothelial Cells ◽  
Kinase Inhibitor ◽  
Receptor Activity ◽  
Microvascular Endothelial Cells ◽  
Mrna Levels ◽  
Dependent Manner ◽  
Extracellular Signal Regulated Kinase ◽  
Extracellular Signal ◽  
Microvascular Endothelial

Adrenomedullin (AM) is a multifunctional peptide hormone, which plays a significant role in vasodilation and angiogenesis, implicating it in hypertension as well as in carcinogenesis. AM exerts its effects via the calcitonin receptor-like receptor (CRLR, now known as CL) complexed with either receptor activity modifying protein (RAMP) 2 or 3. We have investigated the effect of AM on immortalized human microvascular endothelial cells 1, since endothelial cells are a major source as well as a target of AM actions in vivo. Cells treated with AM showed elevated cAMP in a time (5–45 min)-dependent and dose (10−6–10−14 M)-dependent manner. Pre-treatment with the AM receptor antagonist AM22–52 partially suppressed the AM-induced increase in cAMP levels. An increase in extracellular signal-regulated kinase 1/2 phosphorylation was observed after 5 min of treatment with 10−8 M AM. This phosphorylation was specific, since we were able to block the AM-induced effect with 1 μM U0126, a specific mitogen-activated protein/extracellular signal-regulated kinase kinase inhibitor. Using real-time PCR, we were able to show for the first time that AM upregulates peptide and mRNA expression of vascular endothelial growth factor (VEGF). However, AM treatment of cells did not result in increased cell proliferation. Instead, we observed that AM and VEGF induced cell migration, which could be inhibited by the AM22–52 and anti-VEGF antibody respectively. AM also significantly elevated mRNA levels of CL (after 2 and 24 h treatment) and RAMP2 (after 1 and 24 h treatment). The upregulation of the AM receptor at two time points reflects possibly different cellular responses to short- and long-term exposure to AM.

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