scholarly journals Simulated Microgravity Promotes Angiogenesis through RhoA-Dependent Rearrangement of the Actin Cytoskeleton

2017 ◽  
Vol 41 (1) ◽  
pp. 227-238 ◽  
Author(s):  
Fei Shi ◽  
Yong-Chun Wang ◽  
Ze-Bing Hu ◽  
Hong-Yu Xu ◽  
Jing Sun ◽  
...  
Keyword(s):  
Cell Migration ◽  
Actin Filaments ◽  
Wound Closure ◽  
Simulated Microgravity ◽  
Rho Gtpase ◽  
Umbilical Vein ◽  
Critical Role ◽  
Tube Formation ◽  
Small Gtpase ◽  
Rhoa Activity

Background/aims: Microgravity leads to hydrodynamic alterations in the cardiovascular system and is associated with increased angiogenesis, an important aspect of endothelial cell behavior to initiate new vessel growth. Given the critical role of Rho GTPase-dependent cytoskeleton rearrangement in cell migration, small GTPase RhoA might play a potential role in microgravity-induced angiogenesis. Methods: We examined the organization of actin filaments by FITC-conjugated phalloidin staining, as well as the expression and activity of RhoA by quantitative PCR and Western blot, in human umbilical vein endothelial cells (HUVECs) under normal gravity and simulated microgravity. Effect of simulated microgravity on the wound closure and tube formation in HUVECs, and their dependence on RhoA, were also analyzed by cell migration and tube formation assays. Results: We show that in HUVECs actin filaments are disorganized and RhoA activity is reduced by simulated microgravity. Blocking RhoA activity either by C3 transferase Rho inhibitor or siRNA knockdown mimicked the effect of simulated microgravity on inducing actin filament disassembly, followed by enhanced wound closure and tube formation in HUVECs, which closely resembled effects seen on microgravity-treated cells. In contrast, overexpressing RhoA in microgravity-treated HUVECs restored the actin filaments, and decreased wound closure and tube formation abilities. Conclusion: These results suggest that RhoA inactivation is involved in the actin rearrangement-associated angiogenic responses in HUVECs during simulated microgravity.

scholarly journals Gold Nanoparticles Inhibit VEGF165-Induced Migration and Tube Formation of Endothelial Cells via the Akt Pathway

2014 ◽  
Vol 2014 ◽  
pp. 1-11 ◽  
Author(s):  
Yunlong Pan ◽  
Qing Wu ◽  
Li Qin ◽  
Jiye Cai ◽  
Bin Du
Keyword(s):  
Gold Nanoparticles ◽  
Cell Migration ◽  
Endothelial Cell ◽  
Cell Surface ◽  
Umbilical Vein ◽  
Critical Role ◽  
Chorioallantoic Membrane ◽  
Tube Formation ◽  
Endothelial Cell Proliferation ◽  
Akt Pathway

The early stages of angiogenesis can be divided into three steps: endothelial cell proliferation, migration, and tube formation. Vascular endothelial growth factor (VEGF) is considered the most important proangiogenic factor; in particular, VEGF165plays a critical role in angiogenesis. Here, we evaluated whether gold nanoparticles (AuNPs) could inhibit the VEGF165-induced human umbilical vein endothelial cell (HUVEC) migration and tube formation. AuNPs and VEGF165were coincubated overnight at 4°C, after which the effects on cell migration and tube formation were assessed. Cell migration was assessed using a modified wound-healing assay and a transwell chamber assay; tube formation was assessed using a capillary-like tube formation assay and a chick chorioallantoic membrane (CAM) assay. We additionally detected the cell surface morphology and ultrastructure using atomic force microscopy (AFM). Furthermore, Akt phosphorylation downstream of VEGFR-2/PI3K in HUVECs was determined in a Western blot analysis. Our study demonstrated that AuNPs significantly inhibited VEGF165-induced HUVEC migration and tube formation by affecting the cell surface ultrastructure, cytoskeleton and might have inhibited angiogenesis via the Akt pathway.

scholarly journals Long non-coding RNA ARHGAP5-AS1 inhibits migration of breast cancer cell via stabilizing SMAD7 protein

2021 ◽  
Author(s):  
Chen-Long Wang ◽  
Jing-Chi Li ◽  
Ci-Xiang Zhou ◽  
Cheng-Ning Ma ◽  
Di-Fei Wang ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Cell Migration ◽  
Cell Lines ◽  
Cancer Cell ◽  
Breast Cancer Cell ◽  
Rho Gtpase ◽  
Critical Role ◽  
Luciferase Reporter ◽  
Breast Cancer Cell Lines ◽  
Smad7 Protein

Abstract Purpose Tumor metastasis is the main cause of death from breast cancer patients and cell migration plays a critical role in cancer metastasis. Recent studies have shown long non-coding RNAs (lncRNAs) play an essential role in the initiation and progression of cancer. In the present study, the role of an LncRNA, Rho GTPase Activating Protein 5- Antisense 1 (ARHGAP5-AS1) in breast cancer was investigated. Methods RNA sequencing was performed to find out dysregulated LncRNAs in MDA-MB-231-LM2 cells. Transwell migration assays and F-actin staining were utilized to estimate cell migration ability. RNA pulldown assays and RNA immunoprecipitation were used to prove the interaction between ARHGAP5-AS1 and SMAD7. Western blot and immunofluorescence imaging were used to examine the protein levels. Dual luciferase reporter assays were performed to evaluate the activation of TGF-β signaling. Results We analyzed the RNA-seq data of MDA-MB-231 and its highly metastatic derivative MDA-MB-231-LM2 cell lines (referred to as LM2) and identified a novel lncRNA (NR_027263) named as ARHGAP5-AS1, which expression was significantly downregulated in LM2 cells. Further functional investigation showed ARHGAP5-AS1 could inhibit cell migration via suppression of stress fibers in breast cancer cell lines. Afterwards, SMAD7 was further identified to interact with ARHGAP5-AS1 by its PY motif and thus its ubiquitination and degradation was blocked due to reduced interaction with E3 ligase SMURF1 and SMURF2. Moreover, ARHGAP5-AS1 could inhibit TGF-β signaling pathway due to its inhibitory role on SMAD7. Conclusion ARHGAP5-AS1 inhibits breast cancer cell migration via stabilization of SMAD7 protein and could serve as a novel biomarker and a potential target for breast cancer in the future.

Degradation of soluble VEGF receptor-1 by MMP-7 allows VEGF access to endothelial cells

Blood ◽  
2009 ◽  
Vol 113 (10) ◽  
pp. 2363-2369 ◽  
Author(s):  
Ta-Kashi Ito ◽  
Genichiro Ishii ◽  
Seiji Saito ◽  
Keiichi Yano ◽  
Ayuko Hoshino ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Umbilical Vein ◽  
Critical Role ◽  
Inhibitory Effect ◽  
Tube Formation ◽  
Membrane Receptors ◽  
Vegf Receptor ◽  
Migration Assay ◽  
Vegf Inhibitor ◽  
Umbilical Vein Endothelial Cells

AbstractVascular endothelial growth factor (VEGF) signaling in endothelial cells serves a critical role in physiologic and pathologic angiogenesis. Endothelial cells secrete soluble VEGF receptor-1 (sVEGFR-1/sFlt-1), an endogenous VEGF inhibitor that sequesters VEGF and blocks its access to VEGF receptors. This raises the question of how VEGF passes through this endogenous VEGF trap to reach its membrane receptors on endothelial cells, a step required for VEGF-driven angiogenesis. Here, we show that matrix metalloproteinase-7 (MMP-7) degrades human sVEGFR-1, which increases VEGF bioavailability around the endothelial cells. Using a tube formation assay, migration assay, and coimmunoprecipitation assay with human umbilical vein endothelial cells (HUVECs), we show that the degradation of sVEGFR-1 by MMP-7 liberates the VEGF165 isoform from sVEGFR-1. The presence of MMP-7 abrogates the inhibitory effect of sVEGFR-1 on VEGF-induced phosphorylation of VEGF receptor-2 on HUVECs. These data suggest that VEGF escapes the sequestration by endothelial sVEGFR-1 and promotes angiogenesis in the presence of MMP-7.

scholarly journals Cdc42 Promotes Host Defenses against Fatal Infection

2013 ◽  
Vol 81 (8) ◽  
pp. 2714-2723 ◽  
Author(s):  
Keunwook Lee ◽  
Kelli L. Boyd ◽  
Diptiben V. Parekh ◽  
Thomas E. Kehl-Fie ◽  
H. Scott Baldwin ◽  
...  
Keyword(s):  
Rho Gtpase ◽  
Critical Role ◽  
Upper Airway ◽  
Specific Protein ◽  
Small Gtpase ◽  
Host Protection ◽  
Cell Functions ◽  
Airway Infections ◽  
Multiple Cell

ABSTRACTThe small Rho GTPase Cdc42 regulates key signaling pathways required for multiple cell functions, including maintenance of shape, polarity, proliferation, invasion, migration, differentiation, and morphogenesis. As the role of Cdc42-dependent signaling in fibroblastsin vivois unknown, we attempted to specifically delete it in these cells by crossing the Cdc42fl/flmouse with an fibroblast-specific protein 1 (FSP1)-Cre mouse, which is thought to mediate recombination exclusively in fibroblasts. Surprisingly, the FSP1-Cre;Cdc42fl/flmice died at 3 weeks of age due to overwhelming suppurative upper airway infections that were associated with neutrophilia and lymphopenia. Even though major aberrations in lymphoid tissue development were present in the mice, the principal cause of death was severe migration and killing abnormalities of the neutrophil population resulting in an inability to control infection. We also show that in addition to fibroblasts, FSP1-Cre deleted Cdc42 very efficiently in all leukocytes. Thus, by using this nonspecific Cre mouse, we inadvertently demonstrated the importance of Cdc42 in host protection from lethal infections and suggest a critical role for this small GTPase in innate immunity.

scholarly journals The Amot/Patj/Syx signaling complex spatially controls RhoA GTPase activity in migrating endothelial cells

Blood ◽  
2009 ◽  
Vol 113 (1) ◽  
pp. 244-253 ◽  
Author(s):  
Mira Ernkvist ◽  
Nathalie Luna Persson ◽  
Stéphane Audebert ◽  
Patrick Lecine ◽  
Indranil Sinha ◽  
...  
Keyword(s):  
Rho Gtpase ◽  
Critical Role ◽  
Gtpase Activity ◽  
Directional Migration ◽  
Rhoa Activity ◽  
Signaling Complex ◽  
Morpholino Knockdown ◽  
Rhoa Gtpase ◽  
Related Proteins

Abstract Controlled regulation of Rho GTPase activity is an essential component mediating growth factor–stimulated migration. We have previously shown that angiomotin (Amot), a membrane-associated scaffold protein, plays a critical role during vascular patterning and endothelial migration during embryogenesis. However, the signaling pathways by which Amot controls directional migration are not known. Here we have used peptide pull-down and yeast 2-hybrid (Y2H) screening to identify proteins that interact with the C-terminal PDZ-binding motifs of Amot and its related proteins AmotL1 and 2. We report that Amot and its related proteins bind to the RhoA GTPase exchange factor (RhoGEF) protein Syx. We show that Amot forms a ternary complex together with Patj (or its paralogue Mupp1) and Syx. Using FRET analysis, we provide evidence that Amot controls targeting of RhoA activity to lamellipodia in vitro. We also report that, similar to Amot, morpholino knockdown of Syx in zebrafish results in inhibition of migration of intersegmental arteries. Taken together, our results indicate that the directional migration of capillaries in the embryo is governed by the Amot:Patj/Mupp1:Syx signaling that controls local GTPase activity.

scholarly journals Cannabinoid Receptor Type 1 (CB1) Activation Inhibits Small GTPase RhoA Activity and Regulates Motility of Prostate Carcinoma Cells

Endocrinology ◽  
2012 ◽  
Vol 153 (1) ◽  
pp. 29-41 ◽  
Author(s):  
Kasem Nithipatikom ◽  
Ana Doris Gomez-Granados ◽  
Alan T. Tang ◽  
Adam W. Pfeiffer ◽  
Carol L. Williams ◽  
...  
Keyword(s):  
Cell Migration ◽  
Prostate Carcinoma ◽  
Cannabinoid Receptor ◽  
Cell Spreading ◽  
Small Gtpase ◽  
Carcinoma Cells ◽  
Receptor Type ◽  
Rhoa Activity ◽  
Cannabinoid Receptor Type 1

The cannabinoid receptor type 1 (CB1) is a G protein-coupled receptor that is activated in an autocrine fashion by the endocannabinoids (EC), N-arachidonoylethanolamine (AEA) and 2-arachidonoylglycerol (2-AG). The CB1 and its endogenous and synthetic agonists are emerging as therapeutic targets in several cancers due to their ability to suppress carcinoma cell invasion and migration. However, the mechanisms that the CB1 regulates cell motility are not well understood. In this study, we examined the molecular mechanisms that diminish cell migration upon the CB1 activation in prostate carcinoma cells. The CB1 activation with the agonist WIN55212 significantly diminishes the small GTPase RhoA activity but modestly increases the Rac1 and Cdc42 activity. The diminished RhoA activity is accompanied by the loss of actin/myosin microfilaments, cell spreading, and cell migration. Interestingly, the CB1 inactivation with the selective CB1 antagonist AM251 significantly increases RhoA activity, enhances microfilament formation and cell spreading, and promotes cell migration. This finding suggests that endogenously produced EC activate the CB1, resulting in chronic repression of RhoA activity and cell migration. Consistent with this possibility, RhoA activity is significantly diminished by the exogenous application of AEA but not by 2-AG in PC-3 cells (cells with very low AEA hydrolysis). Pretreatment of cells with a monoacylglycerol lipase inhibitor, JZL184, which blocks 2-AG hydrolysis, decreases the RhoA activity. These results indicate the unique CB1 signaling and support the model that EC, through their autocrine activation of CB1 and subsequent repression of RhoA activity, suppress migration in prostate carcinoma cells.

scholarly journals Mechanochemical coupling and junctional forces during collective cell migration

2019 ◽  
Author(s):  
J. Bui ◽  
D. E. Conway ◽  
R. L. Heise ◽  
S.H. Weinberg
Keyword(s):  
Cell Migration ◽  
Rho Gtpases ◽  
Cancer Metastasis ◽  
Rho Gtpase ◽  
Critical Role ◽  
Leading Edge ◽  
Collective Cell Migration ◽  
Gtpase Activity ◽  
Modeling Framework ◽  
Cell Cell

ABSTRACTCell migration, a fundamental physiological process in which cells sense and move through their surrounding physical environment, plays a critical role in development and tissue formation, as well as pathological processes, such as cancer metastasis and wound healing. During cell migration, dynamics are governed by the bidirectional interplay between cell-generated mechanical forces and the activity of Rho GTPases, a family of small GTP-binding proteins that regulate actin cytoskeleton assembly and cellular contractility. These interactions are inherently more complex during the collective migration of mechanically coupled cells, due to the additional regulation of cell-cell junctional forces. In this study, we present a minimal modeling framework to simulate the interactions between mechanochemical signaling in individual cells and interactions with cell-cell junctional forces during collective cell migration. We find that migration of individual cells depends on the feedback between mechanical tension and Rho GTPase activity in a biphasic manner. During collective cell migration, waves of Rho GTPase activity mediate mechanical contraction/extension and thus synchronization throughout the tissue. Further, cell-cell junctional forces exhibit distinct spatial patterns during collective cell migration, with larger forces near the leading edge. Larger junctional force magnitudes are associated with faster collective cell migration and larger tissue size. Simulations of heterogeneous tissue migration exhibit a complex dependence on the properties of both leading and trailing cells. Computational predictions demonstrate that collective cell migration depends on both the emergent dynamics and interactions between cellular-level Rho GTPase activity and contractility, and multicellular-level junctional forces.

scholarly journals Crocetin and Its Glycoside Crocin, Two Bioactive Constituents From Crocus sativus L. (Saffron), Differentially Inhibit Angiogenesis by Inhibiting Endothelial Cytoskeleton Organization and Cell Migration Through VEGFR2/SRC/FAK and VEGFR2/MEK/ERK Signaling Pathways

2021 ◽  
Vol 12 ◽  
Author(s):  
Chen Zhao ◽  
Hio-Tong Kam ◽  
Yan Chen ◽  
Guiyi Gong ◽  
Maggie Pui-Man Hoi ◽  
...  
Keyword(s):  
Cell Migration ◽  
Umbilical Vein ◽  
Tube Formation ◽  
Age Related Macular Degeneration ◽  
Crocus Sativus ◽  
Potential Candidate ◽  
Bioactive Constituents ◽  
Age Related

Crocetin and crocin are two important carotenoids isolated from saffron (Crocus sativus L.), which have been used as natural biomedicines with beneficial effects for improving the suboptimal health status associated with abnormal angiogenesis. However, the anti-angiogenic effects and underlying mechanisms of the effects of crocetin and crocin have not been investigated and compared. The anti-angiogenic effects of crocetin and crocin were tested on human umbilical vein endothelial cells (HUVECs) in vitro, and in zebrafish in vivo. In vivo, crocetin (20 μM) and crocin (50 and 100 μM) significantly inhibited subintestinal vein vessels formation, and a conversion process between them existed in zebrafish, resulting in a difference in their effective concentrations. In the HUVEC model, crocetin (10, 20 and 40 μM) and crocin (100, 200 and 400 μM) inhibited cell migration and tube formation, and inhibited the phosphorylation of VEGFR2 and its downstream pathway molecules. In silico analysis further showed that crocetin had a higher ability to bind with VEGFR2 than crocin. These results suggested that crocetin was more effective than crocin in inhibiting angiogenesis through regulation of the VEGF/VEGFR2 signaling pathway. These compounds, especially crocetin, are potential candidate natural biomedicines for the management of diseases associated with abnormal blood vessel growth, such as age-related macular degeneration.

Abstract 3662: Involvement Of The Small Gtpase Rap1 In Integrin Signaling In Endothelial Cells And Postnatal Neovascularization

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Guillaume Carmona ◽  
Alessia Orlandi ◽  
Henschler Reinhard ◽  
Andreas. M Zeiher ◽  
Stefanie Dimmeler ◽  
...  
Keyword(s):  
Endothelial Cells ◽  
Microvessel Density ◽  
Umbilical Vein ◽  
Critical Role ◽  
Significant Inhibition ◽  
Small Gtpase ◽  
Integrin Signaling ◽  
Wild Type

Ras associated protein 1 (Rap1), a small GTPase of the Ras family, has attracted much attention because of its involvement in several aspects of cell adhesion, including integrin- and cadherin-mediated adhesion. Yet, the role of Rap1 genes for integrin signaling in endothelial cells (EC) and angiogenesis has not been investigated. Human umbilical vein endothelial cells (HUVEC) express Rap1a and Rap1b mRNA as assessed by RT-PCR. In order to determine the contribution of Rap1 activity for angiogenesis, we overexpressed Rap1GAP1, a GTPase activating protein, which specifically inhibits the activity of both Rap1a and Rap1b. Overexpression of Rap1GAP1 led to a significant inhibition of angiogenic sprouting of HUVEC under basal conditions and bFGF stimulation by 44 ± 5 % in a 3-dimensional spheroidal system and blocked tube formation in a matrigel assay, migration and adhesion. In order to separately investigate the role of Rap1a and Rap1b genes in angiogenesis, we performed gene silencing with siRNA. Silencing of either Rap1a or Rap1b significantly and additively blocked the sprouting of HUVEC under basal and bFGF-stimulated conditions (Rap1a-siRNA: 55 ± 5 %, Rap1b-siRNA: 61 ± 9 % and Rap1a+Rap1b siRNA: 73 ± 5% inhibition) and significantly reduced HUVEC migration and adhesion on fibronectin and collagen. Moreover, silencing of Rap1a and Rap1b reduced beta1-integrin affinity in HUVEC, suggesting the importance of Rap1a and Rap1b for inside-out integrin activation in EC. In addition, silencing of Rap1a and Rap1b prevented VEGF-induced PKB/Akt1 activation. These data prompted us to investigate the in vivo role of Rap1a using Rap1a-deficient mice. Interestingly, Rap1a −/− mice are born with a substantially reduced mendelian ratio. Rap1a +/− heterozygote mice displayed decreased microvessel density in comparison to wild-type mice (Rap1a +/+ ) in a matrigel plug assay. Moreover Rap1a +/− and Rap1a −/− displayed significantly reduced microvessel density in ischemic muscles in the model of hind limb ischemia in comparison to wild-type mice (Rap1a +/− : 32 ± 3 % ; Rap1a −/− : 43 ± 3 % inhibition). Thus, our data demonstrated a critical role of Rap1 in the regulation of β1-integrin signaling in endothelial cells and for postnatal neovascularization.

scholarly journals Pointed-end capping by tropomodulin3 negatively regulates endothelial cell motility

2003 ◽  
Vol 161 (2) ◽  
pp. 371-380 ◽  
Author(s):  
Robert S. Fischer ◽  
Kimberly L. Fritz-Six ◽  
Velia M. Fowler
Keyword(s):  
Cell Migration ◽  
Cell Motility ◽  
Actin Filament ◽  
Actin Filaments ◽  
Critical Role ◽  
Leading Edge ◽  
Average Cell ◽  
Transient Overexpression ◽  
End Capping ◽  
Pointed End

Actin filament pointed-end dynamics are thought to play a critical role in cell motility, yet regulation of this process remains poorly understood. We describe here a previously uncharacterized tropomodulin (Tmod) isoform, Tmod3, which is widely expressed in human tissues and is present in human microvascular endothelial cells (HMEC-1). Tmod3 is present in sufficient quantity to cap pointed ends of actin filaments, localizes to actin filament structures in HMEC-1 cells, and appears enriched in leading edge ruffles and lamellipodia. Transient overexpression of GFP–Tmod3 leads to a depolarized cell morphology and decreased cell motility. A fivefold increase in Tmod3 results in an equivalent decrease in free pointed ends in the cells. Unexpectedly, a decrease in the relative amounts of F-actin, free barbed ends, and actin-related protein 2/3 (Arp2/3) complex in lamellipodia are also observed. Conversely, decreased expression of Tmod3 by RNA interference leads to faster average cell migration, along with increases in free pointed and barbed ends in lamellipodial actin filaments. These data collectively demonstrate that capping of actin filament pointed ends by Tmod3 inhibits cell migration and reveal a novel control mechanism for regulation of actin filaments in lamellipodia.

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