scholarly journals Activation of PAR-1/NADPH Oxidase/ROS Signaling Pathways is Crucial for the Thrombin-Induced sFlt-1 Production in Extravillous Trophoblasts: Possible Involvement in the Pathogenesis of Preeclampsia

2015 ◽  
Vol 35 (4) ◽  
pp. 1654-1662 ◽  
Author(s):  
Qi-tao Huang ◽  
Jian-hong Chen ◽  
Li-lin Hang ◽  
Shi-san Liu ◽  
Mei Zhong

Backgrounds/Aims: Preeclampsia was characterized by excessive thrombin generation in placentas and previous researches showed that thrombin could enhance soluble Fms-like tyrosine kinase 1 (sFlt-1) expression in first trimester trophoblasts. However, the detailed mechanism for the sFlt-1 over-production induced by thrombin was largely unknown. The purpose of this study was to explore the possible signaling pathway of thrombin-induced sFlt-1 production in extravillous trophoblasts (EVT). Methods: An EVT cell line (HRT-8/SVneo) was treated with various concentrations of thrombin. The mRNA expression and protein secretion of sFlt-1 in EVT were detected with real-time polymerase chain reaction and ELISA, respectively. The levels of intracellular reactive oxygen species (ROS) production were determined by DCFH-DA. Results: Exposure of EVT to thrombin induced increased intracellular ROS generation and overexpression of sFlt-1 at both mRNA and protein levels in a dose dependent manner. Short interfering RNA (siRNA) directed against PAR-1 or apocynin (an inhibitor of NADPH oxidase) could decrease the intracellular ROS generation and subsequently suppressed the production of sFlt-1 at mRNA and protein levels. Conclusions: Our results suggested that thrombin increased sFlt-1 production in EVT via the PAR-1 /NADPH oxidase /ROS signaling pathway. This also highlights the PAR-1 / NADPH oxidase / ROS pathway might be a potential therapeutic target for the prevention of preeclampsia in the future.

Endocrinology ◽  
2014 ◽  
Vol 155 (5) ◽  
pp. 1908-1920 ◽  
Author(s):  
Gudrun Meinhardt ◽  
Sandra Haider ◽  
Peter Haslinger ◽  
Katharina Proestling ◽  
Christian Fiala ◽  
...  

Formation of migratory extravillous trophoblasts (EVTs) is critical for human placentation and hence embryonic development. However, key regulatory growth factors, hormones, and nuclear proteins controlling the particular differentiation process remain poorly understood. Here, the role of the Wingless (Wnt)-dependent transcription factor T-cell factor-4 (TCF-4) in proliferation and motility was investigated using different trophoblast cell models. Immunofluorescence of first-trimester placental tissues revealed induction of TCF-4 and nuclear recruitment of its coactivator β-catenin in nonproliferating EVTs, whereas membrane-associated β-catenin decreased upon differentiation. In addition, EVTs expressed the TCF-4/β-catenin coactivator Pygopus 2 as well as repressors of the Groucho/transducin-like enhancer of split family. Western blotting revealed Pygopus 2 expression and up-regulation of integrin α1 and nuclear TCF-4 in purified first-trimester cytotrophoblasts (CTBs) differentiating on fibronectin. Concomitantly, elevated TCF-4 mRNA, quantitated by real-time PCR, and increased TCF-dependent luciferase reporter activity were noticed in EVTs of villous explant cultures and differentiated primary CTBs. Gene silencing using specific small interfering RNA decreased TCF-4 transcript and protein levels, TCF-dependent reporter activity as well as basal and Wnt3a-stimulated migration of trophoblastic SGHPL-5 cells and primary CTBs through fibronectin-coated transwells. In contrast, proliferation of SGHPL-5 cells and primary cells, measured by cumulative cell numbers and 5-bromo-2′-deoxy-uridine labeling, respectively, was not affected. Moreover, siRNA-mediated down-regulation of TCF-4 in primary CTBs diminished markers of the differentiated EVT, such as integrin α1 and α5, Snail1, and Notch2. In summary, the data suggest that Wnt/TCF-4-dependent signaling could play a role in EVT differentiation promoting motility and expression of promigratory genes.


2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Yu Chen ◽  
Jingang Cui ◽  
Qinbo Yang ◽  
Chenglin Jia ◽  
Minqi Xiong ◽  
...  

Myocardial fibrosis results from cardiac injuries caused by various pathophysiological mechanisms including myocardial infarction, leading to destruction of myocardial architecture and progressive cardiac dysfunction. Oxidative stress is likely involved in myocardial ischemic injury and the subsequent tissue remodeling mediated by myocardial fibrogenesis. Our current study aimed to evaluate the implication of NADPH oxidase in overproduction of reactive oxygen species and its contribution to the pathogenesis of myocardial fibrogenesis after ischemic injuries. The effects of Apocynin, a selective NADPH oxidase inhibitor, were evaluated in the mouse model of isoproterenol-induced myocardial injury by histopathological approaches and whole-genome gene expression profiling. The results demonstrated that Apocynin was able to inhibit the development of ISO-induced myocardial necrotic lesions and fibrogenesis in a dose-dependent manner. Moreover, the preventive effects of Apocynin on myocardial injuries were associated with suppressed expression of genes implicated in inflammation responses and extracellular matrix, which were remarkably upregulated by isoproterenol administration. In summary, o ur study provides proof-of-concept for the involvement of NADPH oxidase-mediated ROS generation in myocardial ischemic injuries and fibrogenesis, which will benefit the mechanism-based therapeutic development targeting NADPH oxidase and oxidative stress in treating myocardial fibrosis and related disorders.


2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Urszula K. Komarnicka ◽  
Barbara Pucelik ◽  
Daria Wojtala ◽  
Monika K. Lesiów ◽  
Grażyna Stochel ◽  
...  

Abstract[CuI(2,9-dimethyl-1,10-phenanthroline)P(p-OCH3-Ph)2CH2SarcosineGlycine] (1-MPSG), highly stable in physiological media phosphino copper(I) complex—is proposed herein as a viable alternative to anticancer platinum-based drugs. It is noteworthy that, 1-MPSG significantly and selectively reduced cell viability in a 3D spheroidal model of human lung adenocarcinoma (A549), in comparison with non-cancerous HaCaT cells. Confocal microscopy and an ICP-MS analysis showed that 1-MPSG effectively accumulates inside A549 cells with colocalization in mitochondria and nuclei. A precise cytometric analysis revealed a predominance of apoptosis over the other types of cell death. In the case of HaCaT cells, the overall cytotoxicity was significantly lower, indicating the selective activity of 1-MPSG towards cancer cells. Apoptosis also manifested itself in a decrease in mitochondrial membrane potential along with the activation of caspases-3/9. Moreover, the caspase inhibitor (Z-VAD-FMK) pretreatment led to decreased level of apoptosis (more pronouncedly in A549 cells than in non-cancerous HaCaT cells) and further validated the caspases dependence in 1-MPSG-induced apoptosis. Furthermore, the 1-MPSG complex presumably induces the changes in the cell cycle leading to G2/M phase arrest in a dose-dependent manner. It was also observed that the 1-MPSG mediated intracellular ROS alterations in A549 and HaCaT cells. These results, proved by fluorescence spectroscopy, and flow cytometry, suggest that investigated Cu(I) compound may trigger apoptosis also through ROS generation.


2020 ◽  
Vol 318 (3) ◽  
pp. E330-E342 ◽  
Author(s):  
Yingying Yue ◽  
Chang Zhang ◽  
Xuejiao Zhang ◽  
Shitian Zhang ◽  
Qian Liu ◽  
...  

Contraction stimulates skeletal muscle glucose uptake predominantly through activation of AMP-activated protein kinase (AMPK) and Rac1. However, the molecular details of how contraction activates these signaling proteins are not clear. Recently, Axin1 has been shown to form a complex with AMPK and liver kinase B1 during glucose starvation-dependent activation of AMPK. Here, we demonstrate that electrical pulse-stimulated (EPS) contraction of C2C12 myotubes or treadmill exercise of C57BL/6 mice enhanced reciprocal coimmunoprecipitation of Axin1 and AMPK from myotube lysates or gastrocnemius muscle tissue. Interestingly, EPS or exercise upregulated total cellular Axin1 levels in an AMPK-dependent manner in C2C12 myotubes and gastrocnemius mouse muscle, respectively. Also, direct activation of AMPK with 5-aminoimidazole-4-carboxamide ribonucleotide treatment of C2C12 myotubes or gastrocnemius muscle elevated Axin1 protein levels. On the other hand, siRNA-mediated Axin1 knockdown lessened activation of AMPK in contracted myotubes. Further, AMPK inhibition with compound C or siRNA-mediated knockdown of AMPK or Axin1 blocked contraction-induced GTP loading of Rac1, p21-activated kinase phosphorylation, and contraction-stimulated glucose uptake. In summary, our results suggest that an AMPK/Axin1-Rac1 signaling pathway mediates contraction-stimulated skeletal muscle glucose uptake.


2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Ping Jiang ◽  
Jun Cao ◽  
Wen-Hui Bai

Background and Objectives. Estrogen receptor-α(ER-α) plays important roles in hepatocarcinogenesis. Recent studies have shown that ER-αcould lead to cell cycle progression or inhibition of apoptosis. To better understand the role of ER-α, RNA interference (RNAi) was used to inhibit ER-αexpression in the human hepatocellular carcinoma (HCC) cells.Methods. Lentivirus-mediated ER-αsmall interfering RNA (siRNA) was transfected into HCC cells Hep3B. ER-αexpression was monitored by real-time polymerase chain reaction (PCR) and western blot. Cell proliferation, apoptosis, and invasion were examined by methyl thiazol tetrazolium (MTT), flow cytometry (FCM), and invasion assay, respectively.Results. ER-αsiRNA efficiently downregulated the expression of ER-αin Hep3B cells at both mRNA and protein levels in a time-dependent manner. ER-αsiRNA also inhibited cell proliferation and reduced cell invasion (compared with other groups,P<0.05, resp.). Furthermore, knockdown of ER-αslowed down the cell population at S phase and increased the rate of apoptosis (P<0.05, resp.).Conclusion. ER-αknockdown suppressed the growth of HCC cells. Thus, ER-αmay play a very important role in carcinogenesis of HCC and its knockdown may offer a new potential gene therapy approach for human liver cancer in the future.


2021 ◽  
Vol 5 (Supplement_1) ◽  
pp. A766-A767
Author(s):  
Jennifer Jones ◽  
Saswati Banerjee ◽  
Winston E Thompson ◽  
Indrajit Chowdhury

Abstract The formation of a functional corpus luteum (CL) is an absolute requirement for reproductive success and is induced by the mid-cycle surge of luteinizing hormone (LH). The CL is a transient ovarian endocrine structure that maintains pregnancy in primate during the first trimester and in rodents during the entire pregnancy by producing steroid hormone progesterone (P4). CL growth and differentiation are tightly regulated by both survival and cell death signals, including endocrine (LH), intra-ovarian regulators, and cell-cell interactions. Neuregulin-1 (NRG1) is a member of the epidermal growth factor-like factor family that mediates it’s effect through the erythroblastoma (ErbB) family. However, the detailed mechanisms associated with the interplay of NRG1 and its receptors in CL function is not known. Therefore, we examined the role and action of NRG1 and its receptors in the gonadotropin signaling pathway that impacts CL functions. Immunocolocalization of NRG1 and ErbB2/3 in pregnant rat CL on day 14 and 21 suggest that both NRG1 and ErbB2/3 are differentially expressed in CL. Moreover, both NRG1 and ErbB2/3 are highly expressed in rat CL on day 14 compared to day 21. Furthermore, in vitro studies revealed that rat luteal cells (LCs) treated with exogenous tumor necrosis factor-α (TNFα, an inflammatory cytokine) promoted apoptosis in LCs in a dose and time-dependent manner. However, the effects of TNFα was attenuated in presence of exogenous NRG1. Under these experimental conditions, immunoblot analysis indicated that exogenous TNFα treatment in the presence of NRG1 inhibits apoptosis through increased levels of the anti-apoptotic proteins Bcl2 and Bclxl, and activation of ErbB2-ErbB3-PI3K-Akt signaling pathway. Collectively, these studies provide new insights on the NRG1-mediated anti-apoptotic mechanism in LCs through ErbB3-ErbB2-PI3K-Akt→Bcl/Bcl-xL pathway and may have important clinical implications. Acknowledgements: This study was supported in part by National Institutes of Health Grants 1 SC1 GM130544-01A1, 1SC3GM113751 and G12RR03034. This research was conducted in a facility constructed with support from the Research Facilities Improvement Grant C06RR018386 from the National Institutes of Health National Center for Research Resources.


2003 ◽  
Vol 23 (15) ◽  
pp. 5165-5173 ◽  
Author(s):  
Judit Garriga ◽  
Sabyasachi Bhattacharya ◽  
Joaquim Calbó ◽  
Renée M. Marshall ◽  
May Truongcao ◽  
...  

ABSTRACT CDK9 is a CDC2-related kinase and the catalytic subunit of the positive-transcription elongation factor b and the Tat-activating kinase. It has recently been reported that CDK9 is a short-lived protein whose levels are regulated during the cell cycle by the SCFSKP2 ubiquitin ligase complex (R. E. Kiernan et al., Mol. Cell. Biol. 21:7956-7970, 2001). The results presented here are in contrast to those observations. CDK9 protein levels remained unchanged in human cells entering and progressing through the cell cycle from G0, despite dramatic changes in SKP2 expression. CDK9 levels also remained unchanged in cells exiting from mitosis and progressing through the next cell cycle. Similarly, the levels of CDK9 protein did not change as cells exited the cell cycle and differentiated along various lineages. In keeping with these observations, the kinase activity associated with CDK9 was found to not be regulated during the cell cycle. We have also found that endogenous CDK9 is a very stable protein with a half-life (t 1/2) of 4 to 7 h, depending on the cell type. In contrast, when CDK9 is overexpressed, it is not stabilized and is rapidly degraded, with a t 1/2 of less than 1 h, depending on the level of expression. Treatment of cells with proteasome inhibitors blocked the degradation of short-lived proteins, such as p27, but did not affect the expression of endogenous CDK9. Ectopic overexpression of SKP2 led to reduction of p27 protein levels but had no effect on the expression of endogenous CDK9. Finally, downregulation of endogenous SKP2 gene expression by interfering RNA had no effect on CDK9 protein levels, whereas p27 protein levels increased dramatically. Therefore, the SCFSKP2 ubiquitin ligase does not regulate CDK9 expression in a cell cycle-dependent manner.


Endocrinology ◽  
2015 ◽  
Vol 156 (6) ◽  
pp. 2269-2277 ◽  
Author(s):  
Bo Peng ◽  
Hua Zhu ◽  
Liyang Ma ◽  
Yan-ling Wang ◽  
Christian Klausen ◽  
...  

Abstract GnRH is expressed in first-trimester human placenta and increases cell invasion in extravillous cytotrophoblasts (EVTs). Invasive phenotypes have been reported to be regulated by transcription factor activator protein 1 (AP-1) and mesenchymal cadherin-11. The aim of our study was to investigate the roles of AP-1 components (c-FOS/c-JUN) and cadherin-11 in GnRH-induced cell invasion in human EVT cells. Phosphorylated c-FOS and phosphorylated c-JUN were detected in the cell column regions of human first-trimester placental villi by immunohistochemistry. GnRH treatment increased c-FOS, c-JUN, and cadherin-11 mRNA and protein levels in immortalized EVT (HTR-8/SVneo) cells. Moreover, GnRH treatment induced c-FOS and c-JUN protein phosphorylation and nuclear accumulation. Pretreatment with antide, a GnRH antagonist, attenuated GnRH-induced cadherin-11 expression. Importantly, basal and GnRH-induced cadherin-11 expression and cell invasion were reduced by small interfering RNA-mediated knockdown of c-FOS, c-JUN, and cadherin-11 in HTR-8/SVneo cells. Our results suggest that GnRH induces the expression and phosphorylation of the AP-1 transcription factors c-FOS and c-JUN in trophoblast cells, which contributes to GnRH-induced elevation of cadherin-11 expression and cell invasion.


Endocrinology ◽  
2012 ◽  
Vol 153 (2) ◽  
pp. 925-936 ◽  
Author(s):  
York Hunt Ng ◽  
Hua Zhu ◽  
Peter C. K. Leung

The invasion of extravillous cytotrophoblasts (EVT) into the underlying maternal tissues and vasculature is a key step in human placentation. The molecular mechanisms involved in the development of the invasive phenotype of EVT include many that were first discovered for their role in cancer cell metastasis. Previous studies have demonstrated that N-cadherin and its regulatory transcription factor Twist play important roles in the onset and progression of cancers, but their roles in human trophoblastic cell invasion is not clear. The goal of the study was to examine the role of Twist and N-cadherin in human trophoblastic cell invasion. Twist and N-cadherin mRNA and protein levels were determined by RT-PCR and Western blotting in human placental tissues, highly invasive EVT, and poorly invasive JEG-3 and BeWo cells. Whether IL-1β and TGF-β1 regulate Twist mRNA and protein levels in the EVT was also examined. A small interfering RNA strategy was employed to determine the role of Twist and N-cadherin in HTR-8/SVneo cell invasion. Matrigel assays were used to assess cell invasion. Twist and N-cadherin were highly expressed in EVT but were poorly expressed in JEG-3 and BeWo cells. IL-1β and TGF-β1 differentially regulated Twist expression in EVT in a time- and concentration-dependent manner. Small interfering RNA specific for Twist decreased N-cadherin and reduced invasion of HTR-8/SVneo cells. Similarly, a reduction in N-cadherin decreased the invasive capacity of HTR-8/SVneo cells. Twist is an upstream regulator of N-cadherin-mediated invasion of human trophoblastic cells.


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