scholarly journals Tripartite Motif Protein 72 Regulates the Proliferation and Migration of Rat Cardiac Fibroblasts via the Transforming Growth Factor-β Signaling Pathway

Cardiology ◽  
2016 ◽  
Vol 134 (3) ◽  
pp. 340-346 ◽  
Author(s):  
Jianquan Zhao ◽  
Han Lei

Background: The proliferation and migration of cardiac fibroblasts are critical for the progress of cardiac fibrosis. Tripartite motif protein 72 (Trim72), also known as MG53, mediates the dynamic process of membrane fusion and exocytosis in striated muscle. However, the role of Trim72 in the proliferation and migration of cardiac fibroblasts is unknown. Methods: In the present study, we used small interference RNA (siRNA) to silence Trim72 and then investigated the effects of Trim72 on cardiac fibroblast proliferation and migration, which were activated during cardiac remodeling after myocardial infarction. Cardiac fibroblasts were isolated from 2- to 3-day-old neonatal Sprague-Dawley rats and transfected with siRNA. A cell-counting assay was used to determine the proliferation of cardiac fibroblasts. A Boyden chamber assay was performed to determine the migration of cardiac fibroblasts. Results: Our study has, for the first time, demonstrated that Trim72 regulates the cell proliferation and migration of rat cardiac fibroblasts. Furthermore, the data from the gene expression profile microarray analysis indicate that Trim72 depletion can cause downregulation of the transforming growth factor (TGF)-β signaling pathway, suggesting that Trim72 regulates the proliferation and migration of cardiac fibroblasts probably via the TGF-β signaling pathway. Conclusions: We have demonstrated that Trim72 might play a pivotal role in the proliferation of neonatal rat cardiac fibroblasts, which could be a potential target for the treatment of cardiac fibrosis. However, the involvement of other signaling pathways and factors in the formation of cardiac fibrosis cannot be excluded.

2015 ◽  
Vol 117 (suppl_1) ◽  
Author(s):  
Ping Chen ◽  
Dongchao Lv ◽  
Jiahong Xu ◽  
Qiulian Zhou ◽  
Qi Sun ◽  
...  

Fibrosis is one of the most important characteristics of cardiac remodeling during heart failure. The accumulation of extracellular matrix (ECM) within myocardium is the major feature of cardiac fibrosis. microRNA (miR)-19b, a key functional member of miR-19-72 cluster family, has been suggested to be involved in aging-induced heart failure through regulating ECM-related proteins, such as connective tissue growth factor (CTGF), thrombospondin-1 (TSP-1), collagen-1A1, and collagen-3A1. In the current study, we aimed to investigate the role of miR-19b in cardiac fibroblast function and ECM production using neonatal rat cardiac fibroblasts in primary culture. We found that overexpression of miR-19b increased, while inhibition of miR-19b decreased the proliferation and migration of cardiac fibroblasts, using Cell Counting Kit-8 (CCK-8) (0.660±0.019 vs 0.720±0.014 in nc-mimic and miR-19b mimic, 0.506±0.009 vs 0.454±0.008 in nc-inhibitor and miR-19b inhibitor, respectively), EdU incorporation assay (0.059±0.002 vs 0.096±0.006 in nc-mimic and miR-19b mimic, 0.059±0.006 vs 0.040±0.003 in nc-inhibitor and miR-19b inhibitor, respectively), and wound healing assay (0.528±0.024 vs 0.896±0.027 in nc-mimic and miR-19b mimic,0.520±0.028 vs 0.174±0.019 in nc-inhibitor and miR-19b inhibitor, respectively), respectively. Meanwhile, the inhibition of miR-19b downregulated the mRNA levels of α-SMA (0.556±0.048 vs 1.038±0.137 in nc-inhibitor and miR-19b inhibitor, respectively) and collagen-1 (1.023±0.116 vs 0.551±0.033 in nc-inhibitor and miR-19b inhibitor, respectively) in cardiac fibroblasts, indicating a reduction in fibroblast activation and ECM production via miR-19b inhibition. Furthermore, we found that PTEN was negatively regulated by miR-19b in cardiac fibroblasts using western blot analysis. PTEN, a well-known tumor-suppressor gene, has been known to inhibit cell proliferation and migration. However, it remains to be further clarified whether PTEN could mediate the effect of miR-19b in the proliferation, migration and activation of fibroblasts. These data might provide important evidence suggesting that miR-19b could be a potential therapeutic target for cardiac fibrosis.


2021 ◽  
Author(s):  
liu zhiyue ◽  
Zhiyue Liu ◽  
Wen Zhang ◽  
Junli Li ◽  
Lei Xiao ◽  
...  

Abstract Calreticulin (CRT) is an endoplasmic reticulum (ER) chaperone involved in cardiac fibroblasts (CFs) activation. It has been reported that the expression of CRT increased in the process of CFs activation. However, the role of CRT in CFs activation and the mechanism is not yet fully elucidated. Therefore, we aimed to verify whether CRT was involved in CFs activation and the possible mechanism underlying this process. We found that CRT protein level was elevated in AngⅡ-induced CFs activation. Knocking down CRT by its siRNA could decrease the protein expression of connective tissue growth factor (CTGF), α-smooth muscle actin (α-SMA), and transforming growth factor-β (TGF-β), and meanwhile attenuate proliferation and migration ratio of CFs. Moreover, the proliferation and migration rates of CFs were promoted and the expression of CTGF, α-SMA and TGF-β were increased when transfection with high-titer adenovirus of CRT. In AngⅡ-induced CFs, inositol-requiring enzyme 1(IRE-1), one of the main ER pathways, was inhibited through CRT silence and activated through CRT overexpression. Overall, this study demonstrates that CRT overexpression could promote AngⅡ induced-CFs activation by activating IRE1 pathway, which could be a potential target for CFs activation.


Planta Medica ◽  
2017 ◽  
Vol 84 (02) ◽  
pp. 91-99 ◽  
Author(s):  
Yang Xiao ◽  
Wei Chang ◽  
Qing-Qing Wu ◽  
Xiao-Han Jiang ◽  
Ming-Xia Duan ◽  
...  

AbstractFibrosis is a key feature of various cardiovascular diseases and compromises cardiac systolic and diastolic performance. The lack of effective anti-fibrosis drugs is a major contributor to the increasing prevalence of heart failure. The present study was performed to investigate whether the iridoid aucubin alleviates cardiac fibroblast activation and its underlying mechanisms. Neonatal rat cardiac fibroblasts were incubated with aucubin (1, 10, 20, 50 µM) followed by transforming growth factor β1 (TGFβ1, 10 ng/mL) stimulation for 24 h. Fibrosis proliferation was measured by cell counting kit-8 assay. The differentiation of fibroblasts into myofibroblasts was determined by measuring the expression of α-smooth muscle actin. Then, the expressions levels of cardiac fibrosis-related proteins in myofibroblasts were analyzed by western blot and real-time PCR to confirm the anti-fibrosis effect of aucubin. As a result, aucubin suppressed TGFβ1-induced proliferation in fibroblasts and inhibited the TGFβ1-induced activation of fibroblasts to myofibroblasts. In addition, aucubin further attenuated fibrosis-related protein expression in myofibroblasts. Furthermore, this protective effect was related to increased adenosine 5′-monophosphate-activated protein kinase (AMPK) phosphorylation and decreased mammalian target of rapamycin (mTOR) phosphorylation, which was confirmed by an mTOR inhibitor (rapamycin), an AMPK agonist (AICAR) and an AMPKα inhibitor compound C. Collectively, our findings suggest that aucubin protects against TGFβ1-induced fibroblast proliferation, activation and function by regulating the AMPKα/mTOR signal axis.


2015 ◽  
Vol 35 (1) ◽  
pp. 213-226 ◽  
Author(s):  
Xin Zhao ◽  
Kejing Wang ◽  
Yuhua Liao ◽  
Qiutang Zeng ◽  
Yushu Li ◽  
...  

Background/Aims: Hypoxia is a basic pathological challenge that is associated with numerous cardiovascular disorders including aberrant cardiac remodeling. Transforming growth factor beta (TGF-β) signaling pathway plays a pivotal role in mediating cardiac fibroblast (CF) function and cardiac fibrosis. Recent data suggested that microRNA-101a (miR-101a) exerted anti-fibrotic effects in post-infarct cardiac remodeling and improved cardiac function. This study aimed to investigate the potential relationship between hypoxia, miR-101a and TGF-β signaling pathway in CFs. Methods and Results: Two weeks following coronary artery occlusion in rats, the expression levels of both TGFβ1 and TGFβRI were increased, but the expression of miR-101a was decreased at the site of the infarct and along its border. Cultured rat neonatal CFs treated with hypoxia were characterized by the up-regulation of TGFβ1 and TGFβRI and the down-regulation of miR-101a. Delivery of miR-101a mimics significantly suppressed the expression of TGFβRI and p-Smad 3, CF differentiation and collagen content of CFs. These anti-fibrotic effects were abrogated by co-transfection with AMO-miR-101a, an antisense inhibitor of miR-101a. The repression of TGFβRI, a target of miR-101a, was validated by luciferase reporter assays targeting the 3'UTR of TGFβRI. Additionally, we found that overexpression of miR-101a reversed the improved migration ability of CFs and further reduced CF proliferation caused by hypoxia. Conclusion: Our study illustrates that miR-101a exerts anti-fibrotic effects by targeting TGFβRI, suggesting that miR-101a plays a multi-faceted role in modulating TGF-β signaling pathway and cardiac fibrosis.


2019 ◽  
Vol 40 (Supplement_1) ◽  
Author(s):  
A L Reese-Petersen ◽  
M Karsdal ◽  
F Genovese

Abstract Background/Aim Accumulation of extracellular matrix (ECM) proteins is the hallmark of cardiac fibrosis, causing stiffening of the ventricular wall, which can lead to heart failure and ultimately death. Many different cell types and growth factors are involved in this process but fibroblasts are the main source of ECM proteins. Here we present results from an in vitro model indicating that endotrophin (ETP), a collagen type VI fragment, activates cardiac fibroblasts and induces fibrogenesis. Methods The effect of ETP, transforming growth factor (TGF)-β and platelet-derived growth factor (PDGF)-DD on ECM protein synthesis was assessed in a scar-in-a-jar (SiaJ) cell model using human cardiac fibroblasts isolated from the atrium of an adult healthy donor. Cells were seeded in 48-well plates at a density of 30.000 cells/well and incubated for 24H in Dulbecco's Modified Eagle's medium (DMEM) + 10% fetal bovine serum (FBS). Serum starvation was done by seeding the cells for further 24H in DMEM + 0.4% FBS. Fresh medium was added at day 0 with 37.5/25mg/mL Ficoll 70/400 and 1% ascorbic acid, containing 11.75 nM human recombinant ETP, 0.04 nM TGF-β, 0.39 nM PDGF-DD or a vehicle control. Medium was changed and collected at day 3 and 6. Biomarkers of type I (PRO-C1), III (PRO-C3), VI (PRO-C6) collagens and fibronectin (FBN-C) formation were assessed in the medium by ELISAs developed at Nordic Bioscience. Results ETP induced a significant increase in PRO-C1, PRO-C3 and FBN-C (comparable to TGF-β and PDGF-DD) within the first three days of the experiment, compared to the vehicle control. The levels remained significantly increased for PRO-C3 and FBN-C throughout the experiment, and non-significantly elevated for PRO-C1, compared to the vehicle control. PDGF-DD significantly induced synthesis of type VI collagen compared to the vehicle control, while TGF-β induced a small increase in synthesis from day 0–3, after which it seemed to inhibit synthesis. Conclusion For the first time, a direct pro-fibrotic effect on fibroblasts induced by ETP has been shown. This novel pathway of activation could play an important role in regulating cardiac fibrosis, and thus prove to be a therapeutic target. This SiaJ model in combination with the investigated biomarkers of ECM formation could be used to further elucidate the mechanisms behind cardiac fibrosis.


2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Trevi A Ramirez ◽  
Greg Aune

Childhood cancer survivors are at an increased risk of heart disease as a result of their cancer treatments. Drugs like doxorubicin (DOX) are an effective part of treatment regimens, but have been proven to cause acute and chronic cardiotoxicity (DOX tox). An under-investigated aspect of DOX tox is the interstitial fibrosis that the majority of patients develop. This project aims to better understand the pathology of DOX-induced cardiac fibrosis and the role of the pro-fibrotic transforming growth factor-beta (TGFb) signaling pathway. Research in the area of fibrosis and the effect of DOX on cardiac fibroblasts will increase our understanding of DOX tox. This understanding will allow for improved treatment of pediatric cancer patients by reducing the cardiotoxic sequelae of many standard chemotherapy regimens. Cardiac fibroblasts, isolated from 3 week old mice and treated with 5 μM DOX, showed an increase in nuclear pSMAD compared to control cells via fluorescent immunocytology (2.06 ± 0.26 vs 1.13 ± 0.15, p<0.05). Mice treated with 3 mg/kg DOX injections from 2 weeks to 6 weeks of age showed increased TGFb staining in the left ventricle (1.83 ± 0.34 vs 0.87 ± 0.28, p<0.05) a week after treatment ceased. A subset of mice were followed into old age and sacrificed at 80 weeks. A clear increase in TGFb was seen with age. However, 80 week mice that were exposed to DOX early in life showed a greater increase in TGFb staining compared to untreated 80 week old mice (44.50 ± 2.48 vs 30.93 ± 2.30, p<0.001). Early DOX exposure causes chronic molecular changes as evidenced by acute and chronic changes in signaling molecules in cardiac tissue. Changes in collagen seen in earlier studies and increases in MMP-2 from the literature suggest a cardiac remodeling phenotype in DOX-exposed animals. This project demonstrates that DOX initiates changes to pro-fibrotic pathways, seemingly driven by the TGFb signaling pathway.


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