scholarly journals Identification of ACTA2 as a Key Contributor to Venous Malformation

Author(s):  
Song Wang ◽  
Zifu Zhou ◽  
Jing Li ◽  
Yu Wang ◽  
Hongwen Li ◽  
...  

Objectives: Proteomics and high connotation functional gene screening (HCS) were used to screen key functional genes that play important roles in the pathogenesis of venous malformation. Furthermore, this study was conducted to analyze and explore their possible functions, establish a gene mutation zebrafish model, and perform a preliminary study to explore their possible pathogenic mechanisms in venous malformation.Methods: Pathological and normal tissues from patients with disseminated venous malformation were selected for Tandem Mass Tag (TMT) proteomics analysis to identify proteins that were differentially expressed. Based on bioinformatics analysis, 20 proteins with significant differential expression were selected for HCS to find key driver genes and characterize the expression of these genes in patients with venous malformations. In vitro experiments were then performed using human microvascular endothelial cells (HMEC-1). A gene mutant zebrafish model was also constructed for in vivo experiments to explore gene functions and pathogenic mechanisms.Results: The TMT results showed a total of 71 proteins that were differentially expressed as required, with five of them upregulated and 66 downregulated. Based on bioinformatics and proteomics results, five highly expressed genes and 15 poorly expressed genes were selected for functional screening by RNAi technology. HCS screening identified ACTA2 as the driver gene. Quantitative polymerase chain reaction (qPCR) and western blot were used to detect the expression of ACTA2 in the pathological tissues of patients with venous malformations and in control tissues, and the experimental results showed a significantly lower expression of ACTA2 in venous malformation tissues (P < 0.05). Cell assays on the human microvascular endothelial cells (HMEC-1) model showed that cell proliferation, migration, invasion, and angiogenic ability were all significantly increased in the ACTA2 over-expression group (P < 0.05), and that overexpression of ACTA2 could improve the inhibitory effect on vascular endothelial cell proliferation. We constructed an ACTA2-knockdown zebrafish model and found that the knockdown of ACTA2 resulted in defective vascular development, disruption of vascular integrity, and malformation of micro vein development in zebrafish. Further qPCR assays revealed that the knockdown of ACTA2 inhibited the Dll4/notch1 signaling pathway, Ephrin-B2 signaling pathway, and vascular integrity-related molecules and activated the Hedgehog signaling pathway.Conclusion: This study revealed that ACTA2 deficiency is an important factor in the pathogenesis of venous malformation, resulting in the disruption of vascular integrity and malformed vascular development. ACTA2 can be used as a potential biomarker for the treatment and prognosis of venous malformations.

2012 ◽  
Vol 302 (6) ◽  
pp. C839-C852 ◽  
Author(s):  
Wei P. Feinstein ◽  
Bing Zhu ◽  
Silas J. Leavesley ◽  
Sarah L. Sayner ◽  
Thomas C. Rich

Cyclic AMP signals encode information required to differentially regulate a wide variety of cellular responses; yet it is not well understood how information is encrypted within these signals. An emerging concept is that compartmentalization underlies specificity within the cAMP signaling pathway. This concept is based on a series of observations indicating that cAMP levels are distinct in different regions of the cell. One such observation is that cAMP production at the plasma membrane increases pulmonary microvascular endothelial barrier integrity, whereas cAMP production in the cytosol disrupts barrier integrity. To better understand how cAMP signals might be compartmentalized, we have developed mathematical models in which cellular geometry as well as total adenylyl cyclase and phosphodiesterase activities were constrained to approximate values measured in pulmonary microvascular endothelial cells. These simulations suggest that the subcellular localizations of adenylyl cyclase and phosphodiesterase activities are by themselves insufficient to generate physiologically relevant cAMP gradients. Thus, the assembly of adenylyl cyclase, phosphodiesterase, and protein kinase A onto protein scaffolds is by itself unlikely to ensure signal specificity. Rather, our simulations suggest that reductions in the effective cAMP diffusion coefficient may facilitate the formation of substantial cAMP gradients. We conclude that reductions in the effective rate of cAMP diffusion due to buffers, structural impediments, and local changes in viscosity greatly facilitate the ability of signaling complexes to impart specificity within the cAMP signaling pathway.


2021 ◽  
Vol 18 ◽  
Author(s):  
Juxuan Ruan ◽  
Lei Wang ◽  
Jiheng Dai ◽  
Jing Li ◽  
Ning Wang ◽  
...  

Objective: Angiogenesis led by brain microvascular endothelial cells (BMECs) contributes to the remission of brain injury after brain ischemia reperfusion. In this study, we investigated the effects of hydroxysafflor yellow A(HSYA) on angiogenesis of BMECs injured by OGD/R via SIRT1-HIF-1α-VEGFA signaling pathway. Methods: The OGD/R model of BMECs was established in vitro by OGD for 2h and reoxygenation for 24h. At first, the concentrations of vascular endothelial growth factor (VEGF), Angiopoietin (ang) and platelet-derived growth factor (PDGF) in supernatant were detected by ELISA, and the proteins expression of VEGFA, Ang-2 and PDGFB in BMECs were tested by western blot; the proliferation, adhesion, migration (scratch healing and transwell) and tube formation experiment of BMECs; the expression of CD31 and CD34 were tested by immunofluorescence staining. The levels of sirtuin1(SIRT1), hypoxia-inducible factor-1α (HIF-1α), VEGFA mRNA and protein were tested. Results: HSYA up-regulated the levels of VEGF, Ang and PDGF in the supernatant of BMECs under OGD/R, and the protein expression of VEGFA, Ang-2 and PDGFB were increased; HSYA could significantly alleviate the decrease of cell proliferation, adhesion, migration and tube formation ability of BMECs during OGD/R; HSYA enhanced the fluorescence intensity of CD31 and CD34 of BMECs during OGD/R; HSYA remarkably up-regulated the expression of SIRT1, HIF-1α, VEGFA mRNA and protein after OGD/R, and these increase decreased after SIRT1 was inhibited. Conclusion: SIRT1-HIF-1α-VEGFA signaling pathway is involved in HSYA improves angiogenesis of BMECs injured by OGD/R.


2020 ◽  
Author(s):  
Xue Fan ◽  
Meng Li ◽  
Min Xiao ◽  
Cong Liu ◽  
Mingguo Xu

Abstract Background: Kawasaki disease (KD) leads to coronary artery damage and the etiology of KD is unknown. The present study was designed to explore the differentially expressed genes (DEGs) in KD serum-induced human coronary artery endothelial cells (HCAECs) by RNA-sequence (RNA-seq). Methods: HCAECs were stimulated with serum (15% (v/v)), which were collected from 20 healthy children and 20 KD patients, for 24 hours. DEGs were then detected and analyzed by RNA-seq and bioinformatics analysis. Results: The expression of SMAD1, SMAD6, CD34, CXCL1, PITX2, and APLN was validated by qPCR. 102 genes, 59 up-regulated and 43 down-regulated genes, were significantly differentially expressed in KD groups. GO enrichment analysis showed that DEGs were enriched in cellular response to cytokines, cytokine-mediated signaling pathway, and regulation of immune cells migration and chemotaxis. KEGG signaling pathway analysis showed that DEGs were mainly involved in cytokine−cytokine receptor interaction, chemokine signaling pathway, and TGF−β signaling pathway. Besides, the mRNA expression levels of SMAD1, SMAD6, CD34, CXCL1, and APLN in the KD group were significantly up-regulated compared with the normal group, whilePITX2 was significantly down-regulated. Conclusion: 102 DEGs in KD serum-induced HCAECs were identified, and six new targets were proposed as potential indicators of KD.


2020 ◽  
Vol 40 (5) ◽  
pp. 1195-1206 ◽  
Author(s):  
Danting Cao ◽  
Andrew M. Mikosz ◽  
Alexandra J. Ringsby ◽  
Kelsey C. Anderson ◽  
Erica L. Beatman ◽  
...  

Objective: MicroRNA-126-3p (miR-126) is required for angiogenesis during organismal development or the repair of injured arterial vasculature. The role of miR-126 in lung microvascular endothelial cells, which are essential for gas exchange and for lung injury repair and regeneration, remains poorly understood. Considering the significant heterogeneity of endothelial cells from different vascular beds, we aimed to determine the role of miR-126 in regulating lung microvascular endothelial cell function and to elucidate its downstream signaling pathways. Approach and Results: Overexpression and knockdown of miR-126 in primary human lung microvascular endothelial cells (HLMVEC) were achieved via transfections of miR-126 mimics and antisense inhibitors. Increasing miR-126 levels in HLMVEC reduced cell proliferation, weakened tube formation, and increased cell apoptosis, whereas decreased miR-126 levels stimulated cell proliferation and tube formation. Whole-genome RNA sequencing revealed that miR-126 was associated with an antiangiogenic and proapoptotic transcriptomic profile. Using validation assays and knockdown approaches, we identified that the effect of miR-126 on HLMVEC angiogenesis was mediated by the LAT1 (L-type amino acid transporter 1), via regulation of mTOR (mammalian target of rapamycin) signaling. Furthermore, downregulation of miR-126 in HLMVEC inhibited cell apoptosis and improved endothelial tube formation during exposure to environmental insults such as cigarette smoke. Conclusions: miR-126 inhibits HLMVEC angiogenic function by targeting the LAT1-mTOR signaling axis, suggesting that miR-126 inhibition may be useful for conditions associated with microvascular loss, whereas miR-126 augmentation may help control unwanted microvascular angiogenesis.


Blood ◽  
2007 ◽  
Vol 110 (11) ◽  
pp. 516-516
Author(s):  
Mobeen Malik ◽  
Ying-Yu Chen ◽  
Martha F. Kienzle ◽  
Ronald G. Collman ◽  
Andrzej Ptasznik

Abstract Infiltration of activated monocytes into the brain of HIV-infected patients is a prerequisite for the development of HIV-associated dementia (HAD). The chemokine stromal derived factor-1α (SDF-1α) is expressed at increased levels in the central nervous system (CNS) of HAD patients and elicits chemotaxis and other cellular effects through its receptor CXCR4. In this project, we investigated the intracellular signaling pathway by which SDF-1α mediates the movement and attachment of monocytes to brain microvascular endothelia, and which may contribute to their infiltration into the CNS in HAD. We demonstrated that SDF-1α stimulates migration of primary human monocytes through its receptor CXCR4, and decreases monocyte adherence to surfaces coated with ICAM-1. SDF-1α also decreases monocyte adherence to brain microvascular endothelial cells (BMVEC) activated with the pro-inflammatory cytokines TNF-α or IL-1β, or with recombinant HIV-1 envelope glycoprotein (gp120), which increase endothelial cells expression of ICAM-1. The decreased monocyte adherence was linked to down regulation of the activation-dependent epitope of the β2 integrin LFA-1 which is a ligand for ICAM-1. We then demonstrated that the Src family kinase Lyn is a central modulator of migration and LFA-1-mediated adhesion of SDF-1α-stimulated primary monocytes. Using siRNA knockdown we achieved 80% down regulation of Lyn kinase in human monocytes. Lyn down regulation decreased SDF-1α-mediated migration and prevented its inhibition of monocyte attachment to ICAM-1 coated surfaces and activated BMVEC. These data indicate that in SDF-1α-stimulated primary human monocytes Lyn is a positive regulator of cell migration, and a negative regulator of cell adhesion to BMVEC by inhibiting the ICAM-1 binding activity of the LFA-1 integrin. Thus, CXCR4-triggered inside-out integrin signaling, through Lyn, inhibits adherence and stimulates movement of monocytes towards SDF-1α gradient on BMVEC monolayers. These results provide new insight into the intracellular signaling cascade that controls primary human monocytes movement and attachment at the blood brain barrier.


2012 ◽  
Vol 6 ◽  
pp. BCBCR.S9592 ◽  
Author(s):  
Hui Yu ◽  
Sumathy Mohan ◽  
Mohan Natarajan

Tumors require blood supply to survive, grow, and metastasize. This involves the process of angiogenesis signaling for new blood vessel growth into a growing tumor mass. Understanding the mechanism of the angiogenic signaling pathway and neovascularization for breast cancer cell proliferation and growth would help to develop molecular interventions and achieve disease free survival. Our hypothesis is that the surviving cancer cell(s) after radiotherapy can initiate angiogenic signaling pathway in the neighboring endothelial cells resulting in neovascularization for breast cancer cell growth. The angiogenic signaling pathway is initiated by angiogenic factors, VEGF and FGF-2, through activation of a transcriptional regulator NF-κB, which in turn is triggered by therapeutic doses of radiation exposure Human breast adenocarcinoma cells (MCF-7 cells) were exposed to Cesium-137 (137Cs) γ rays to a total dose of 2 Gy at a dose rate of 1.03 Gy/min. The results of mobility shift assay showed that radiation at clinical doses (2 Gy) could induce NF-κB DNA-binding activity. Then, we examined the communication of angiogenic signals from irradiated MCF-7 cells to vascular endothelial cells. At the protein level, the western blot showed induction of angiogenic factors VEGF and FGF-2 in MCF-7 cells irradiated with 2 Gy. Inhibition of NF-κB activation attenuated VEGF and FGF-2 levels. These factors are secreted into the medium. The levels of VEGF and FGF-2 in the extra cellular medium were both increased, after 2 Gy exposures. We also observed corresponding expression of VEGFR2 and FGFR1 in non-irradiated endothelial cells that were co-cultured with irradiated MCF-7 cells. In support of this, in vitro tube formation assays provided evidence that irradiated MCF-7 cells transmit signals to potentiate cultured non-irradiated endothelial cells to form tube networks, which is the hallmark of neovascularization. Inhibition of NF-κB activation attenuated irradiated MCF-7-induced tube network formation. The data provide evidence that the radiation exposure is responsible for tumor growth and maintenance by inducing an angiogenic signaling pathway through activation of NF-κB.


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