scholarly journals Hypoxia Suppresses TGF-B1-Induced Cardiac Myocyte Myofibroblast Transformation by Inhibiting Smad2/3 and Rhoa Signaling Pathways

2018 ◽  
Vol 45 (1) ◽  
pp. 250-257 ◽  
Author(s):  
Zhankui Yan ◽  
Daifei Shen ◽  
Jilin Liao ◽  
Yanmei Zhang ◽  
Yicun Chen ◽  
...  

Background/Aims: Hypoxia modulation of transforming growth factor (TGF)- β-induced signaling during myofibroblast transformation is dependent on the specific cell type. The purpose of this study was to explore the effects of hypoxia on myofibroblast transformation of TGF-β1-induced cardiomyocyte H9c2 cells. Methods: H9c2 cells were cultured for intermittent hypoxia treatment and TGF-β1 treatment. α-Smooth muscle actin (α-SMA) expression was examined by western blotting and immunofluorescence after treatment. To further explore the possible mechanism for this effect, the effects of hypoxia on three early TGF-β-dependent signaling pathways, i.e. the Smad2/3, RhoA and mitogen-activated protein kinase (MAPK) pathways, were screened by western blotting. Results: Intermittent hypoxia induced TGF-β1 expression, but had no effect on α-SMA expression. Exogenous TGF-β1 alone upregulated α-SMA expression in H9c2 cells in a concentration- and time-dependent manner. α-SMA expression declined with the duration of hypoxia after intermittent hypoxia and exogenous TGF-β1 co-treatment. Phospho-JNK and phospho-p38 levels were not significantly altered after TGF-β1 and hypoxia treatment. However, levels of phospho-ERK increased after TGF-β1 treatment and continued to increase after hypoxia co-treatment. The activation of phospho-Smad2/3 and phospho-RhoA induced by TGFβ1 was significantly reduced after hypoxia co-treatment. Conclusion: Hypoxia can inhibit TGF-β1-induced H9c2 myofibroblast transformation, based on inhibition of α-SMA expression by suppressing signaling downstream of TGF-β1, Smad2/3 and RhoA. It suggested that TGF-β-mediated cardiomyocyte transformation is not involved in hypoxia-mediated fibrosis.

2020 ◽  
Vol 318 (5) ◽  
pp. E710-E722 ◽  
Author(s):  
Fuxin Wang ◽  
Hsun-Ming Chang ◽  
Yuyin Yi ◽  
Yung-Ming Lin ◽  
Hong Li ◽  
...  

There is increasing evidence showing the importance of vitamin D (Vit D) and its nuclear receptor, the Vit D receptor (VDR), in female reproductive health. Transforming growth factor-β1 (TGF-β1) and its functional receptors are expressed in human oocytes and granulosa cells that participate in follicular development and ovulation. Recently, Sma- and Mad-related protein 3 (SMAD3; a downstream effector of TGF-β1) has been proposed to mediate crosstalk between the Vit D and TGF-β1 signaling pathways, but this relationship has not been fully explored and has yet to be tested in human granulosa-lutein (hGL) cells. In this study, we showed that TGF-β1 significantly promoted the expression of VDR, and this stimulatory effect occurred through the activin receptor-like kinase 5 type I receptor-mediated SMAD3 and ERK1/2 signaling pathways in hGL cells. Additionally, we showed that Vit D increased the expression of cyclooxygenase 2 (COX-2) and the synthesis of prostaglandin E2 (PGE2) in a time- and dose-dependent manner. Furthermore, we demonstrated a synergistic effect of TGF-β1 and Vit D on the expression of COX-2 and synthesis of PGE2, and this effect could be attenuated by silencing the expression of VDR. Our findings indicate that TGF-β1 upregulates the expression of VDR, which promotes Vit D-induced COX-2 expression and subsequent PGE2 production by activating the SMAD3 and ERK1/2 signaling pathways in hGL cells.


2010 ◽  
Vol 299 (3) ◽  
pp. F648-F655 ◽  
Author(s):  
Hisayo Fujita ◽  
Mariko Hida ◽  
Katsuyoshi Kanemoto ◽  
Keiichi Fukuda ◽  
Michio Nagata ◽  
...  

We previously reported that p38 mitogen-activated protein kinase (p38) and phosphorylated ERK are upregulated in cyst epithelium of human renal dysplasia and obstructive uropathy in fetal lambs (Omori S, Fukuzawa R, Hida M, Awazu M. Kidney Int 61: 899–906, 2002; Omori S, Kitagawa H, Koike J, Fujita H, Hida M, Pringle KC, Awazu M. Kidney Int 73: 1031–1037, 2008). Dysplastic epithelium is characterized by proliferation, apoptosis, and upregulation of Pax2 and transforming growth factor (TGF)-β1. In the present study, we investigated whether cyclic mechanical stretching of ureteric bud cells, a mimic of the hydrodynamic derangement after fetal urinary tract obstruction, reproduces events seen in vivo. Cyclic stretch activated p38 and ERK and upregulated Pax2 expression in a time-dependent manner in ureteric bud cells. Stretch-stimulated Pax2 expression was suppressed by a p38 inhibitor, SB203580, or a MEK inhibitor, PD98059. 5-Deoxyuridine incorporation was increased by stretch at 24 h, which was also abolished by SB203580 or PD98059. On the other hand, apoptosis was not induced at 24 h by stretch but was significantly increased at 48 h. TGF-β1 secretion was increased by stretch at 24 h, which was inhibited by SB203580 or PD98059. Inhibition of p38 or ERK as well as anti-TGF-β antibody abolished the stretch-induced apoptosis. Finally, exogenous TGF-β1 induced apoptosis of ureteric bud cells, which was inhibited by SB203580 and PD98059. In conclusion, cyclic stretch induces Pax2 upregulation, proliferation, and TGF-β1-mediated apoptosis, features characteristic of dysplastic epithelium, via p38 and ERK in ureteric bud cells.


2019 ◽  
Vol 2019 ◽  
pp. 1-14 ◽  
Author(s):  
Ning Liu ◽  
Jiao Feng ◽  
Xiya Lu ◽  
Zhilu Yao ◽  
Qing Liu ◽  
...  

Objective. Liver fibrosis is a consequence of wound-healing responses to chronic liver insult and may progress to liver cirrhosis if not controlled. This study investigated the protection against liver fibrosis by isorhamnetin. Methods. Mouse models of hepatic fibrosis were established by intraperitoneal injection of carbon tetrachloride (CCl4) or bile duct ligation (BDL). Isorhamnetin 10 or 30 mg/kg was administered by gavage 5 days per week for 8 weeks in the CCl4 model and for 2 weeks in the BDL model. Protein and mRNA expressions were assayed by western blotting, immunohistochemistry, and quantitative real-time polymerase chain reaction. Results. Isorhamnetin significantly inhibited liver fibrosis in both models, inhibiting hepatic stellate cell (HSC) activation, extracellular matrix (ECM) deposition, and autophagy. The effects were associated with downregulation of transforming growth factor β1 (TGF-β1) mediation of Smad3 and p38 mitogen-activated protein kinase (MAPK) signaling pathways. Conclusion. Isorhamnetin protected against liver fibrosis by reducing ECM formation and autophagy via inhibition of TGF-β1-mediated Smad3 and p38 MAPK signaling pathways.


2020 ◽  
Author(s):  
Yuxin Zhang ◽  
Shenji Lu ◽  
Kexin Wang ◽  
Shuai Fan ◽  
Lili Xu ◽  
...  

Abstract Background: Joint capsule fibrosis caused by excessive inflammation results in post-traumatic joint contracture (PTJC). Transforming growth factor (TGF)-β1 plays a key role in PTJC by regulating fibroblast functions, however, cytokine-induced TGF-β1 expression in specific cell types remains poorly characterized. Macrophage migration inhibitory factor (MIF) is a proinflammatory cytokine involved in inflammation- and fibrosis-associated pathophysiology. Results: In this study, we investigated whether MIF can facilitate TGF-β1 production from fibroblasts and regulate joint capsule fibrosis following PTJC. Our data demonstrated that MIF and TGF-β1 significantly increased in fibroblasts of injured rat posterior joint capsules. Treatment the lesion sites with MIF inhibitor 4-Iodo-6-phenylpyrimidine (4-IPP) reduced TGF-β1 production and relieved joint capsule inflammation and fibrosis. In vitro, MIF facilitated TGF-β1 expression in primary joint capsule fibroblasts by activating mitogen-activated protein kinase (MAPK) (P38, ERK) signaling through coupling with membrane surface receptor CD74, which in turn affected fibroblast functions and promoted MIF production. Conclusion: Our results reveal a novel function of trauma-induced MIF in the occurrence and development of joint capsule fibrosis. Further investigation of the underlying mechanism may provide potential therapeutic targets for PTJC.


2003 ◽  
Vol 14 (2) ◽  
pp. 529-544 ◽  
Author(s):  
Sofia Edlund ◽  
Shizhong Bu ◽  
Norbert Schuster ◽  
Pontus Aspenström ◽  
Rainer Heuchel ◽  
...  

The inhibitory Smad7, a direct target gene for transforming growth factor-β (TGF-β), mediates TGF-β1–induced apoptosis in several cell types. Herein, we report that apoptosis of human prostate cancer PC-3U cells induced by TGF-β1 or Smad7 overexpression is caused by a specific activation of the p38 mitogen-activated protein kinase pathway in a TGF-β–activated kinase 1 (TAK1)- and mitogen-activated protein kinase kinase 3 (MKK3)-dependent manner. Expression of dominant negative p38, dominant negative MKK3, or incubation with the p38 selective inhibitor [4-(4-fluorophenyl)-2-(4-methylsulfinylphenyl)-5-(4-pyridyl)1H-imidazole], prevented TGF-β1–induced apoptosis. The expression of Smad7 was required for TGF-β–induced activation of MKK3 and p38 kinases, and endogenous Smad7 was found to interact with phosphorylated p38 in a ligand-dependent manner. Ectopic expression of wild-type TAK1 promoted TGF-β1–induced phosphorylation of p38 and apoptosis, whereas dominant negative TAK1 reduced TGF-β1–induced phosphorylation of p38 and apoptosis. Endogenous Smad7 was found to interact with TAK1, and TAK1, MKK3, and p38 were coimmunoprecipitated with Smad7 in transiently transfected COS1 cells. Moreover, ectopically expressed Smad7 enhanced the coimmunoprecipitation of HA-MKK3 and Flag-p38, supporting the notion that Smad7 may act as a scaffolding protein and facilitate TAK1- and MKK3-mediated activation of p38.


2021 ◽  
Vol 22 (6) ◽  
pp. 2952
Author(s):  
Tzu-Yu Hou ◽  
Shi-Bei Wu ◽  
Hui-Chuan Kau ◽  
Chieh-Chih Tsai

Transforming growth factor-β1 (TGF-β1)-induced myofibroblast transdifferentiation from orbital fibroblasts is known to dominate tissue remodeling and fibrosis in Graves’ ophthalmopathy (GO). However, the signaling pathways through which TGF-β1 activates Graves’ orbital fibroblasts remain unclear. This study investigated the role of the mitogen-activated protein kinase (MAPK) pathway in TGF-β1-induced myofibroblast transdifferentiation in human Graves’ orbital fibroblasts. The MAPK pathway was assessed by measuring the phosphorylation of p38, c-Jun N-terminal kinase (JNK), and extracellular-signal-regulated kinase (ERK) by Western blots. The expression of connective tissue growth factor (CTGF), α-smooth muscle actin (α-SMA), and fibronectin representing fibrogenesis was estimated. The activities of matrix metalloproteinases (MMPs) and tissue inhibitors of metalloproteinases (TIMPs) responsible for extracellular matrix (ECM) metabolism were analyzed. Specific pharmacologic kinase inhibitors were used to confirm the involvement of the MAPK pathway. After treatment with TGF-β1, the phosphorylation levels of p38 and JNK, but not ERK, were increased. CTGF, α-SMA, and fibronectin, as well as TIMP-1 and TIMP-3, were upregulated, whereas the activities of MMP-2/-9 were inhibited. The effects of TGF-β1 on the expression of these factors were eliminated by p38 and JNK inhibitors. The results suggested that TGF-β1 could induce myofibroblast transdifferentiation in human Graves’ orbital fibroblasts through the p38 and JNK pathways.


2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Huakan Zhao ◽  
Lei Wu ◽  
Guifang Yan ◽  
Yu Chen ◽  
Mingyue Zhou ◽  
...  

AbstractCancer development and its response to therapy are regulated by inflammation, which either promotes or suppresses tumor progression, potentially displaying opposing effects on therapeutic outcomes. Chronic inflammation facilitates tumor progression and treatment resistance, whereas induction of acute inflammatory reactions often stimulates the maturation of dendritic cells (DCs) and antigen presentation, leading to anti-tumor immune responses. In addition, multiple signaling pathways, such as nuclear factor kappa B (NF-kB), Janus kinase/signal transducers and activators of transcription (JAK-STAT), toll-like receptor (TLR) pathways, cGAS/STING, and mitogen-activated protein kinase (MAPK); inflammatory factors, including cytokines (e.g., interleukin (IL), interferon (IFN), and tumor necrosis factor (TNF)-α), chemokines (e.g., C-C motif chemokine ligands (CCLs) and C-X-C motif chemokine ligands (CXCLs)), growth factors (e.g., vascular endothelial growth factor (VEGF), transforming growth factor (TGF)-β), and inflammasome; as well as inflammatory metabolites including prostaglandins, leukotrienes, thromboxane, and specialized proresolving mediators (SPM), have been identified as pivotal regulators of the initiation and resolution of inflammation. Nowadays, local irradiation, recombinant cytokines, neutralizing antibodies, small-molecule inhibitors, DC vaccines, oncolytic viruses, TLR agonists, and SPM have been developed to specifically modulate inflammation in cancer therapy, with some of these factors already undergoing clinical trials. Herein, we discuss the initiation and resolution of inflammation, the crosstalk between tumor development and inflammatory processes. We also highlight potential targets for harnessing inflammation in the treatment of cancer.


2021 ◽  
Vol 49 (3) ◽  
pp. 030006052199651
Author(s):  
Jie Yang ◽  
Enzi Feng ◽  
Yanxin Ren ◽  
Shun Qiu ◽  
Liufang Zhao ◽  
...  

Objectives To identify key long non-coding (lnc)RNAs responsible for the epithelial–mesenchymal transition (EMT) of CNE1 nasopharyngeal carcinoma cells and to investigate possible regulatory mechanisms in EMT. Methods CNE1 cells were divided into transforming growth factor (TGF)-β1-induced EMT and control groups. The mRNA and protein expression of EMT markers was determined by real-time quantitative PCR and western blotting. Differentially expressed genes (DEGs) between the two groups were identified by RNA sequencing analysis, and DEG functions were analyzed by gene ontology and Kyoto Encyclopedia of Genes and Genomes analyses. EMT marker expression was re-evaluated by western blotting after knockdown of a selected lncRNA. Results TGF-β1-induced EMT was characterized by decreased E-cadherin and increased vimentin, N-cadherin, and Twist expression at both mRNA and protein levels. Sixty lncRNA genes were clustered in a heatmap, and mRNA expression of 14 dysregulated lncRNAs was consistent with RNA sequencing. Knockdown of lnc-PNRC2-1 increased expression of its antisense gene MYOM3 and reduced expression of EMT markers, resembling treatment with the TGF-β1 receptor inhibitor LY2109761. Conclusion Various lncRNAs participated indirectly in the TGF-β1-induced EMT of CNE1 cells. Lnc-PNRC2-1 may be a key regulator of this and is a potential target to alleviate CNE1 cell EMT.


2011 ◽  
Vol 286 (22) ◽  
pp. 19215-19228 ◽  
Author(s):  
Frederic Cailotto ◽  
Pascal Reboul ◽  
Sylvie Sebillaud ◽  
Patrick Netter ◽  
Jean-Yves Jouzeau ◽  
...  

Transforming growth factor (TGF)-β1 stimulates extracellular PPi (ePPi) generation and promotes chondrocalcinosis, which also occurs secondary to hyperparathyroidism-induced hypercalcemia. We previously demonstrated that ANK was up-regulated by TGF-β1 activation of ERK1/2 and Ca2+-dependent protein kinase C (PKCα). Thus, we investigated mechanisms by which calcium could affect ePPi metabolism, especially its main regulating proteins ANK and PC-1 (plasma cell membrane glycoprotein-1). We stimulated articular chondrocytes with TGF-β1 under extracellular (eCa2+) or cytosolic Ca2+ (cCa2+) modulations. We studied ANK, PC-1 expression (quantitative RT-PCR, Western blotting), ePPi levels (radiometric assay), and cCa2+ input (fluorescent probe). Voltage-operated Ca2+-channels (VOC) and signaling pathways involved were investigated with selective inhibitors. Finally, Ank promoter activity was evaluated (gene reporter). TGF-β1 elevated cCa2+ and ePPi levels (by up-regulating Ank and PC-1 mRNA/proteins) in an eCa2+ dose-dependent manner. TGF-β1 effects were suppressed by cCa2+ chelation or L- and T-VOC blockade while being mostly reproduced by ionomycin. In the same experimental conditions, the activation of Ras, the phosphorylation of ERK1/2 and PKCα, and the stimulation of Ank promoter activity were affected similarly. Activation of SP1 (specific protein 1) and ELK-1 (Ets-like protein-1) transcription factors supported the regulatory role of Ca2+. SP1 or ELK-1 overexpression or blockade experiments demonstrated a major contribution of ELK-1, which acted synergistically with SP1 to activate Ank promoter in response to TGF-β1. TGF-β1 promotes input of eCa2+ through opening of L- and T-VOCs, to potentiate ERK1/2 and PKCα signaling cascades, resulting in an enhanced activation of Ank promoter and ePPi production in chondrocyte.


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