Abstract 244: Vascular Induction of Adam17 in vitro and in Vivo By Angiotensin Ii: Potential Involvement of a Hypoxia Responsible Element

Hypertension ◽  
2012 ◽  
Vol 60 (suppl_1) ◽  
Author(s):  
Takehiko Takayanagi ◽  
Allison M Bourne ◽  
Tomonori Kobayashi ◽  
Nariaki Yanagawa ◽  
Akira Takaguri ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Protein Expression ◽  
Cardiovascular System ◽  
Promoter Activation ◽  
Feed Forward ◽  
Feed Forward Loop ◽  
Fold Induction ◽  
Enzymatic Activation

ADAM17 has been shown to play critical roles in angiotensin II (AngII)-dependent as well as independent types of pathophysiological vascular remodeling in vitro and in vivo. Enzymatic activation of ADAM17 by AngII has been described, however, little is known regarding regulation of ADAM17 protein expression in the cardiovascular system. Here we test our hypothesis that AngII induces ADAM17 protein expression to originate a feed forward loop of ADAM17 activation/induction in the vasculature. 8 week old control mice were infused with 1000 ng/kg/min AngII for 2 weeks via osmotic minipump. Serum starved rat VSMCs were stimulated with 100 nM AngII. ADAM17 expression was evaluated by immunohistochemistry and immunoblotting, respectively. In AngII-infused mice, marked ADAM17 induction was seen in vasculatures in heart and kidney, and carotid arteries and aortae. In VSMCs, AngII as well as PDGF-BB (50 ng/mL) time-dependently induced ADAM17 expression up to 24 hours (AngII 24h: 2.34±0.25 fold induction). Both AngII and PDGF-BB also stimulated ADAM17 promoter activity in VSMCs (AngII 24h: 2.90±0.17 fold induction). The ADAM17 promoter contains 6 typical hypoxia responsible elements (HREs). By using deletion and mutation constructs, the PDGF-BB response seems to require HRE4 located between -991 to -410 of the promoter. AngII-induced promoter activation was also lost in the HRE4 mutant. Moreover, both AngII and PDGF-BB stimulated HIF-1alpha protein expression in VSMCs at 4-8 hours. From these data, we conclude that AngII and PDGF induce ADAM17 expression in VSMCs via HIF1alpha/HRE-dependent transcriptional upregulation. The induction of ADAM17 via the HIF1/HRE-dependent mechanism likely promotes a feed-forward loop of ADAM17 activation/induction under a variety of pathophysiological conditions including hypoxia/ischemia leading to end organ damages in the cardiovascular system.

scholarly journals COX-2 mediates angiotensin II-induced (pro)renin receptor expression in the rat renal medulla

2014 ◽  
Vol 307 (1) ◽  
pp. F25-F32 ◽  
Author(s):  
Fei Wang ◽  
Xiaohan Lu ◽  
Kexin Peng ◽  
Li Zhou ◽  
Chunling Li ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Protein Expression ◽  
Renal Medulla ◽  
Receptor Expression ◽  
Ang Ii ◽  
Cox 2 ◽  
Renin Content

(Pro)renin receptor (PRR) is predominantly expressed in the distal nephron where it is activated by angiotensin II (ANG II), resulting in increased renin activity in the renal medulla thereby amplifying the de novo generation and action of local ANG II. The goal of the present study was to test the role of cycloxygenase-2 (COX-2) in meditating ANG II-induced PRR expression in the renal medulla in vitro and in vivo. Exposure of primary rat inner medullary collecting duct cells to ANG II induced sequential increases in COX-2 and PRR protein expression. When the cells were pretreated with a COX-2 inhibitor NS-398, ANG II-induced upregulation of PRR protein expression was almost completely abolished, in parallel with the changes in medium active renin content. The inhibitory effect of NS-398 on the PRR expression was reversed by adding exogenous PGE2. A 14-day ANG II infusion elevated renal medullary PRR expression and active and total renin content in parallel with increased urinary renin, all of which were remarkably suppressed by the COX-2 inhibitor celecoxib. In contrast, plasma and renal cortical active and total renin content were suppressed by ANG II treatment, an effect that was unaffected by COX-2 inhibition. Systolic blood pressure was elevated with ANG II infusion, which was attenuated by the COX-2 inhibition. Overall, the results obtained from in vitro and in vivo studies established a crucial role of COX-2 in mediating upregulation of renal medullary PRR expression and renin content during ANG II hypertension.

scholarly journals A miR-9-5p/FOXO1/CPEB3 feed-forward loop drives the progression of hepatocellular carcinoma

2021 ◽  
Author(s):  
Hui Hu ◽  
Wei Huang ◽  
Jianye Li ◽  
Qiong Zhang ◽  
Ya-Ru Miao ◽  
...  
Keyword(s):  
Hepatocellular Carcinoma ◽  
Regulatory Role ◽  
Luciferase Reporter ◽  
Migration And Invasion ◽  
Loss Of Function ◽  
Feed Forward ◽  
Feed Forward Loop ◽  
Regulatory Module

Abstract Background Hepatocellular carcinoma (HCC) is the third leading cause of cancer-related death worldwide, but its regulatory mechanism remains unclear. Although many TFs and miRNAs are reported to be important in HCC, their co-regulation and FFL modules in HCC development are needed to be investigated. Methods The feed-forward loop (FFL) regulatory module was identified by analyzing the miRNA and transcription factor co-regulatory network for differentially expressed genes between tumors and matched adjacent tissue samples. Gene expression and regulatory role of HCC development by key FFL in vitro and in vivo were validated by qPCR, Western blotting, cell proliferation assay, migration and invasion assay and experiments in nude mice with hepatoma xenografts. Results Here, by bioinformatics analysis, we identified FFL regulatory module miR-9-5p/FOXO1/CPEB3 may play critical roles in HCC progression. Gain- and loss-of-function studies demonstrated that miR-9-5p promote hepatocarcinogenesis, while FOXO1 and CPEB3 inhibit hepatocarcinoma growth. Furthermore, CPEB3 was firstly identified as a direct downstream target of miR-9-5p and FOXO1 by luciferase reporter assay and ChIP-Seq data, which was negatively regulated by miR-9-5p and activated by FOXO1. Following, the miR-9-5p/FOXO1/CPEB3 FFL was associated with poor prognosis and promoted cell growth and tumorigenesis of HCC in both in vitro and in vivo experiments. Conclusion Our study newly identified the existence of miR-9-5p/FOXO1/CPEB3 FFL and revealed its regulatory role in HCC progression, which may represent a new potential therapeutic target for cancer treatment.

scholarly journals A feed-forward loop between SorLA and HER3 determines heregulin response and neratinib resistance

2020 ◽  
Author(s):  
Hussein Al-Akhrass ◽  
James R.W. Conway ◽  
Annemarie Svane Aavild Poulsen ◽  
Ilkka Paatero ◽  
Jasmin Kaivola ◽  
...  
Keyword(s):  
Breast Cancer ◽  
Xenograft Model ◽  
Therapy Resistance ◽  
Mitogen Activated Protein Kinase ◽  
Current Evidence ◽  
Dependent Manner ◽  
Feed Forward ◽  
Feed Forward Loop

Current evidence indicates that resistance to HER2-targeted therapies is frequently associated with HER3 and active signaling via HER2-HER3 dimers, particularly in the context of breast cancer. Thus, understanding the response to HER2-HER3 signaling and the regulation of the dimer per se remains essential to decipher therapy relapse mechanisms. Here, we demonstrate that signaling by HER3 growth factor ligands, heregulins, support the transcription of a type-1 transmembrane sorting receptor, sortilin-related receptor (SorLA; SORL1) downstream of the mitogen-activated protein kinase pathway. In addition, we demonstrate that SorLA interacts directly with HER3, forming a trimeric complex with HER2 and HER3 to attenuate lysosomal degradation of the dimer through a Rab4-dependent manner. In line with a role for SorLA in supporting the stability of the HER2 and HER3 receptors, loss of SorLA compromised heregulin-induced cell proliferation and sensitized metastatic anti-HER2 therapy-resistant breast cancer cells to neratinib in cancer spheroids in vitro and in vivo in a zebrafish brain xenograft model. Collectively, our results demonstrate a novel feed-forward loop consisting of heregulin, HER2-HER3 and SorLA, which controls breast cancer growth and anti-HER2 therapy resistance in vitro and in vivo.SignificanceHER3 signaling, through ERK/MAPK, upregulates SorLA and SorLA controls the trafficking and stability of HER3 to support cancer proliferation and neratinib resistance.

scholarly journals Genetically Modified Mouse Models Used for Studying the Role of the AT2Receptor in Cardiac Hypertrophy and Heart Failure

2011 ◽  
Vol 2011 ◽  
pp. 1-5 ◽  
Author(s):  
Maria D. Avila ◽  
James P. Morgan ◽  
Xinhua Yan
Keyword(s):  
Heart Failure ◽  
Angiotensin Ii ◽  
Cardiac Hypertrophy ◽  
Cardiovascular System ◽  
Mouse Models ◽  
Genetically Modified ◽  
Cardiovascular Effects

The actions of Angiotensin II have been implicated in many cardiovascular conditions. It is widely accepted that the cardiovascular effects of Angiotensin II are mediated by different subtypes of receptors: AT1and AT2. These membrane-bound receptors share a part of their nucleic acid but seem to have different distribution and pathophysiological actions. AT1mediates most of the Angiotensin II actions since it is ubiquitously expressed in the cardiovascular system of the normal adult. Moreover AT2is highly expressed in the developing fetus but its expression in the cardiovascular system is low and declines after birth. However the expression of AT2appears to be modulated by pathological states such as hypertension, myocardial infarction or any pathology associated to tissue remodeling or inflammation. The specific role of this receptor is still unclear and different studies involvingin vivo and in vitroexperiments have shown conflicting data. It is essential to clarify the role of the AT2receptor in the different pathological states as it is a potential site for an effective therapeutic regimen that targets the Angiotensin II system. We will review the different genetically modified mouse models used to study the AT2receptor and its association with cardiac hypertrophy and heart failure.

Abstract 640: Overexpression of Vasohibin-2 Exacerbates Development of Angiotensin II-Induced Thoracic Aortic Aneurysms Independent of VeEGF

2017 ◽  
Vol 37 (suppl_1) ◽  
Author(s):  
Michihiro Okuyama ◽  
Haruhito A Uchida ◽  
Ryoko Umebayashi ◽  
Yuki Kakio ◽  
Hidemi Takeuchi ◽  
...  
Keyword(s):  
Angiotensin Ii ◽  
Protein Expression ◽  
Aortic Arch ◽  
Gelatin Zymography ◽  
Annexin V ◽  
Aortic Aneurysms ◽  
Tunel Staining ◽  
Significant Difference

Objective: Chronic angiotensin II (AngII) infusion promotes both thoracic (TAAs) and abdominal aortic aneurysms (AAAs) in mice. Vasohibin-2 (VASH2) is known to cause angiogenesis at the sprouting front of neovascularization. The purpose of this study was to examine whether VASH2 influenced AngII-induced TAAs. Methods: Male C57BL/6J mice (10-week-old) were injected with VASH2 or LacZ expressing adenovirus (Ad; 7.5 x 10 9 vp/100 μL) via tail vein at 2 week intervals. One week after the first injection, subcutaneous infusion of either AngII (1,000 ng/kg/min) or saline by mini osmotic pumps was started for 3 weeks. Consequently, mice were divided into 4 groups: AngII + Ad VASH2 (n=22), AngII + Ad LacZ (n=21), saline + Ad VASH2 (n=10), saline + Ad LacZ (n=8). Next, in order to examine whether VASH2 affected TAAs via VEGF regulation, bevacizumab was intraperitoneally administrated into mice; AngII + Ad VASH2 + saline (n=15), AngII + Ad VASH2 + bevacizumab (n=15). TAAs were evaluated in all mice by en face method. Third, human aortic smooth muscle cells (hSMCs) were infected with Ad VASH2 or Ad LacZ, stimulated with or without AngII to evaluate further mechanism. Result: Intima area of aortic arch was significantly larger in AngII + Ad VASH2 group than in AngII + Ad LacZ group (19.78 ± 0.40 mm 3 vs 17.74 ± 0.44 mm 3 , P < 0.001). Gelatin zymography demonstrated that AngII upregulated latent MMP-2 expression, and activated MMP-2 most prominently in AngII + VASH2 group. Protein expression of p21 and p53 in thoracic aortas was enhanced in AngII + VASH2 group. Positive TUNEL staining was observed in thoracic aortic wall of AngII + VASH2 group. No significant difference in intima area of aortic arch between AngII + Ad VASH2 + saline group and AngII + Ad VASH2 + bevacizumab group. In vitro, the same results were observed regarding protein expression of p21 and p53, and TUNEL staining. In addition, Annexin-V staining was detected only in AngII + VASH2 group. Conclusion: Overexpression of VASH2 accelerated development of AngII-induced TAAs in vivo. VASH2-induced cell apoptosis may influence AngII-induced TAA formation independent of VEGF.

Cardiovascular Effects of Micromeria graeca (L.) Benth. ex Rchb in Normotensive and Hypertensive Rats

2020 ◽  
Vol 20 (8) ◽  
pp. 1253-1261
Author(s):  
Mourad Akdad ◽  
Mohamed Eddouks
Keyword(s):  
Blood Pressure ◽  
Cardiovascular System ◽  
Arterial Blood Pressure ◽  
Antihypertensive Activity ◽  
Computer Assisted ◽  
Hypertensive Rats ◽  
Vasorelaxant Effect ◽  
Arterial Blood

Aims: The present study was performed in order to analyze the antihypertensive activity of Micromeria graeca (L.) Benth. ex Rchb. Background: Micromeria graeca (L.) Benth. ex Rchb is an aromatic and medicinal plant belonging to the Lamiaceae family. This herb is used to treat various pathologies such as cardiovascular disorders. Meanwhile, its pharmacological effects on the cardiovascular system have not been studied. Objective: The present study aimed to evaluate the effect of aqueous extract of aerial parts of Micromeria graeca (AEMG) on the cardiovascular system in normotensive and hypertensive rats. Methods: In this study, the cardiovascular effect of AEMG was evaluated using in vivo and in vitro investigations. In order to assess the acute effect of AEMG on the cardiovascular system, anesthetized L-NAME-hypertensive and normotensive rats received AEMG (100 mg/kg) orally and arterial blood pressure parameters were monitored during six hours. In the sub-chronic study, rats were orally treated for one week, followed by blood pressure assessment during one week of treatment. Blood pressure was measured using a tail-cuff and a computer-assisted monitoring device. In the second experiment, isolated rat aortic ring pre-contracted with Epinephrine (EP) or KCl was used to assess the vasorelaxant effect of AEMG. Results: Oral administration of AEMG (100 mg/kg) provoked a decrease of arterial blood pressure parameters in hypertensive rats. In addition, AEMG induced a vasorelaxant effect in thoracic aortic rings pre-contracted with EP (10 μM) or KCl (80 mM). This effect was attenuated in the presence of propranolol and methylene blue. While in the presence of glibenclamide, L-NAME, nifedipine or Indomethacin, the vasorelaxant effect was not affected. Conclusion: This study showed that Micromeria graeca possesses a potent antihypertensive effect and relaxes the vascular smooth muscle through β-adrenergic and cGMP pathways.

scholarly journals Upregulation of ETV2 Expression Promotes Endothelial Differentiation of Human Dental Pulp Stem Cells

2021 ◽  
Vol 30 ◽  
pp. 096368972097873
Author(s):  
Jing Li ◽  
Youming Zhu ◽  
Na Li ◽  
Tao Wu ◽  
Xianyu Zheng ◽  
...  
Keyword(s):  
Protein Expression ◽  
Dental Pulp ◽  
Tube Formation ◽  
Endothelial Differentiation ◽  
Cell Source ◽  
Lentiviral Infection ◽  
Mrna And Protein Expression ◽  
Human Dental Pulp

The lack of vasculogenesis often hampers the survivability and integration of newly engineered tissue grafts within the host. Autologous endothelial cells (ECs) are an ideal cell source for neovascularization, but they are limited by their scarcity, lack of proliferative capacity, and donor site morbidity upon isolation. The objective of this study was to determine whether differentiation of human dental pulp stem cells (DPSCs) into the endothelial lineage can be enhanced by recombinant ETV2 overexpression. DPSCs were extracted from fresh dental pulp tissues. ETV2 overexpression in DPSCs was achieved by lentiviral infection and cellular morphological changes were evaluated. The mRNA and protein expression levels of endothelial-specific markers were assessed through quantitative real-time polymerase chain reaction, western blot, immunofluorescence staining, and flow cytometry. The tube formation assay and Matrigel plug assay were also performed to evaluate the angiogenic potential of the ETV2-transduced cells in vitro and in vivo, respectively. Additionally, proteomic analysis was performed to analyze global changes in protein expression following ETV2 overexpression. After lentiviral infection, ETV2-overexpressing DPSCs showed endothelial-like morphology. Compared with control DPSCs, significantly higher mRNA and protein expression levels of endothelial-specific genes, including CD31, VE-Cadherin, VEGFR1, and VEGFR2, were detected in ETV2-overexpressing DPSCs. Moreover, ETV2 overexpression enhanced capillary-like tube formation on Matrigel in vitro, as well as neovascularization in vivo. In addition, comparative proteomic profiling showed that ETV2 overexpression upregulated the expression of vascular endothelial growth factor (VEGF) receptors, which was indicative of increased VEGF signaling. Taken together, our results indicate that ETV2 overexpression significantly enhanced the endothelial differentiation of DPSCs. Thus, this study shows that DPSCs can be a promising candidate cell source for tissue engineering applications.

scholarly journals Honeysuckle Aqueous Extracts Induced let-7a Suppress EV71 Replication and Pathogenesis In Vitro and In Vivo and Is Predicted to Inhibit SARS-CoV-2

Viruses ◽  
2021 ◽  
Vol 13 (2) ◽  
pp. 308
Author(s):  
Ying-Ray Lee ◽  
Chia-Ming Chang ◽  
Yuan-Chieh Yeh ◽  
Chi-Ying F. Huang ◽  
Feng-Mao Lin ◽  
...  
Keyword(s):  
Protein Expression ◽  
Western Blotting ◽  
Expression Profiles ◽  
Plaque Assay ◽  
Virus Titer ◽  
Enterovirus 71 ◽  
Luciferase Reporter ◽  
Pathogen Invasion

Honeysuckle (Lonicera japonica Thunb) is a traditional Chinese medicine (TCM) with an antipathogenic activity. MicroRNAs (miRNAs) are small non-coding RNA molecules that are ubiquitously expressed in cells. Endogenous miRNA may function as an innate response to block pathogen invasion. The miRNA expression profiles of both mice and humans after the ingestion of honeysuckle were obtained. Fifteen overexpressed miRNAs overlapped and were predicted to be capable of targeting three viruses: dengue virus (DENV), enterovirus 71 (EV71) and SARS-CoV-2. Among them, let-7a was examined to be capable of targeting the EV71 RNA genome by reporter assay and Western blotting. Moreover, honeysuckle-induced let-7a suppression of EV71 RNA and protein expression as well as viral replication were investigated both in vitro and in vivo. We demonstrated that let-7a targeted EV71 at the predicted sequences using luciferase reporter plasmids as well as two infectious replicons (pMP4-y-5 and pTOPO-4643). The suppression of EV71 replication and viral load was demonstrated in two cell lines by luciferase activity, RT-PCR, real-time PCR, Western blotting and plaque assay. Furthermore, EV71-infected suckling mice fed honeysuckle extract or inoculated with let-7a showed decreased clinical scores and a prolonged survival time accompanied with decreased viral RNA, protein expression and virus titer. The ingestion of honeysuckle attenuates EV71 replication and related pathogenesis partially through the upregulation of let-7a expression both in vitro and in vivo. Our previous report and the current findings imply that both honeysuckle and upregulated let-7a can execute a suppressive function against the replication of DENV and EV71. Taken together, this evidence indicates that honeysuckle can induce the expression of let-7a and that this miRNA as well as 11 other miRNAs have great potential to prevent and suppress EV71 replication.

scholarly journals TMOD-15. EFFICACY OF THE MDM2 INHIBITOR KRT-232 IN GLIOBLASTOMA PATIENT-DERIVED XENOGRAFT MODELS

2020 ◽  
Vol 22 (Supplement_2) ◽  
pp. ii231-ii231
Author(s):  
Rachael Vaubel ◽  
Ann Mladek ◽  
Yu Zhao ◽  
Shiv K Gupta ◽  
Minjee Kim ◽  
...  
Keyword(s):  
Target Genes ◽  
Xenograft Model ◽  
Culture Conditions ◽  
Patient Derived Xenograft ◽  
Fold Induction ◽  
Extended Survival ◽  
Mdm2 Amplification ◽  
Mdm2 Inhibitor

Abstract Non-genotoxic reactivation of p53 by MDM2 inhibitors represents a promising therapeutic strategy for tumors with wild-type TP53, particularly tumors harboring MDM2 amplification. MDM2 controls p53 levels by targeting it for degradation, while disruption of the MDM2-p53 interaction causes rapid accumulation of p53 and activation of the p53 pathway. We examined the efficacy of the small molecule MDM2 inhibitor KRT-232, alone and in combination with radiation therapy (RT), in MDM2-amplified and/or p53 wildtype patient-derived xenograft (PDX) models of glioblastoma in vitro and in vivo. In vitro, glioblastoma PDX explant cultures showed sensitivity to KRT-232, both tumors with MDM2 amplification (GBM108 and G148) and non-amplified but TP53-wildtype lines (GBM10, GBM14, and GBM39), with IC50s ranging from 300-800 nM in FBS culture conditions. A TP53 p.F270C mutant PDX (GBM43) was inherently resistant, with IC50 &gt;3000 nM. In the MDM2-amplified GBM108 line, KRT-232 led to a robust (5-6 fold) induction of p53-target genes p21, PUMA, and NOXA, with initiation of both apoptosis and senescence. Expression of p21 and PUMA was greater with KRT-232 in combination with RT (25-35 fold induction), while stable knock-down of p53 in GBM108 led to complete resistance to KRT-232. In contrast, GBM10 showed lower induction of p21 and PUMA (2-3 fold) and was more resistant to KRT-232. In an orthotopic GBM108 xenograft model, treatment with KRT-232 +/- RT for one week extended survival from 22 days (placebo) to 46 days (KRT-232 alone); combination KRT-232 + RT further extended survival (77 days) over RT alone (31 days). KRT-232 is an effective treatment in a subset of glioblastoma pre-clinical models alone and in combination with RT. Further studies are underway to understand the mechanisms conferring innate sensitivity or resistance to KRT-232.

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