scholarly journals The Functional Role of Zinc Finger E Box-Binding Homeobox 2 (Zeb2) in Promoting Cardiac Fibroblast Activation

2018 ◽  
Vol 19 (10) ◽  
pp. 3207 ◽  
Author(s):  
Fahmida Jahan ◽  
Natalie Landry ◽  
Sunil Rattan ◽  
Ian Dixon ◽  
Jeffrey Wigle
Keyword(s):  
Smooth Muscle ◽  
Zinc Finger ◽  
Cardiac Fibrosis ◽  
Smooth Muscle Actin ◽  
Critical Role ◽  
Cardiac Fibroblast ◽  
In Vivo Studies ◽  
Fibroblast Activation ◽  
E Box

Following cardiac injury, fibroblasts are activated and are termed as myofibroblasts, and these cells are key players in extracellular matrix (ECM) remodeling and fibrosis, itself a primary contributor to heart failure. Nutraceuticals have been shown to blunt cardiac fibrosis in both in-vitro and in-vivo studies. However, nutraceuticals have had conflicting results in clinical trials, and there are no effective therapies currently available to specifically target cardiac fibrosis. We have previously shown that expression of the zinc finger E box-binding homeobox 2 (Zeb2) transcription factor increases as fibroblasts are activated. We now show that Zeb2 plays a critical role in fibroblast activation. Zeb2 overexpression in primary rat cardiac fibroblasts is associated with significantly increased expression of embryonic smooth muscle myosin heavy chain (SMemb), ED-A fibronectin and α-smooth muscle actin (α-SMA). We found that Zeb2 was highly expressed in activated myofibroblast nuclei but not in the nuclei of inactive fibroblasts. Moreover, ectopic Zeb2 expression in myofibroblasts resulted in a significantly less migratory phenotype with elevated contractility, which are characteristics of mature myofibroblasts. Knockdown of Zeb2 with siRNA in primary myofibroblasts did not alter the expression of myofibroblast markers, which may indicate that Zeb2 is functionally redundant with other profibrotic transcription factors. These findings add to our understanding of the contribution of Zeb2 to the mechanisms controlling cardiac fibroblast activation.

Abstract 353: Bone Marrow Fibroblast Progenitor Cell-derived Exosomes Activate Resident Fibroblast and Augment Pressure Overload Induced Cardiac Fibrosis in IL10KO Mice

2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Suresh K Verma ◽  
Venkata N Girikipathi ◽  
Maria Cimini ◽  
Zhongjian Cheng ◽  
Moshin Khan ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Cardiac Fibrosis ◽  
Culture Media ◽  
Critical Role ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Cardiac Fibroblast ◽  
Paracrine Factors ◽  
Fibroblast Activation ◽  
Resident Fibroblast

Background: Activated fibroblasts (myoFBs) play critical role in cardiac fibrosis, however, their origin in diseased heart remains uncertain. Previous studies suggest the contribution of bone marrow fibroblasts progenitor cells (FPC) in pressure overload (PO)-induced cardiac fibrosis and inflammation acts as catalyst in this process. Recently others and we have shown that paracrine mediators packaged in exosomes play important role in cardiac pathophysiology. Thus, we hypothesized that exosome-derived from IL10KO-FPC augments PO-induced resident cardiac fibroblast activation and therefore, aggravate cardiac fibrosis. Methods and Results: Cardiac fibrosis was induced in Wild-type (WT) and IL10-knockout (IL10KO) mice by transverse aortic constriction (TAC). TAC-induced left ventricular (LV) dysfunction and fibrosis were further exaggerated in IL10KO mice. PO-enhanced FPC (Prominin1 + cells) mobilization and homing in IL10KO mice compared to WT mice. To establish the IL10KO-FPC paracrine signaling, exosomes were isolated from WT and IL10KO BM-FPC culture media and characterized for proteins/miRNA. IL10 KO FPC-exosomes showed altered packaging of signature fibrotic miR and proteins. To explore whether FPC-exosomes modulate resident fibroblast activation, adult cardiac fibroblasts were treated with WT and IL10KO FPC-derived exosomes. IL10KO-FPC-derived exosomes exaggerate TGFβ 2 -induced activation of adult fibroblasts. These data suggest that fibrotic remodeling factors (miRs and/or proteins) packaged in IL10KO-FPC exosomes are sufficient to enhance the resident cardiac fibroblast activation and mediate cardiac fibrotic remodeling IL10 treatment significantly inhibits TGFβ 2 -induced FPC to myoFBs transition. Conclusion: Taken together, our findings suggest that paracrine factors secreted by BM-FPC augment resident cardiac fibroblast activation and fibrosis in pressure overloaded myocardium and IL10 negatively regulates this process. Ongoing investigations using molecular approaches will provide a better understanding on the mechanistic and therapeutic aspects of IL10 on PO-induced cardiac fibrosis and heart failure.

scholarly journals Intermittent hypoxia mediated by TSP1 dependent on STAT3 induces cardiac fibroblast activation and cardiac fibrosis

eLife ◽  
2020 ◽  
Vol 9 ◽  
Author(s):  
Qiankun Bao ◽  
Bangying Zhang ◽  
Ya Suo ◽  
Chen Liu ◽  
Qian Yang ◽  
...  
Keyword(s):  
Intermittent Hypoxia ◽  
Cardiac Fibrosis ◽  
Synergistic Effects ◽  
Cardiac Fibroblasts ◽  
Cardiac Fibroblast ◽  
Ang Ii ◽  
Fibroblast Activation ◽  
Obstructive Sleep

Intermittent hypoxia (IH) is the predominant pathophysiological disturbance in obstructive sleep apnea (OSA), known to be independently associated with cardiovascular diseases. However, the effect of IH on cardiac fibrosis and molecular events involved in this process are unclear. Here, we tested IH in angiotensin II (Ang II)-induced cardiac fibrosis and signaling linked to fibroblast activation. IH triggered cardiac fibrosis and aggravated Ang II-induced cardiac dysfunction in mice. Plasma thrombospondin-1 (TSP1) content was upregulated in both IH-exposed mice and OSA patients. Moreover, both in vivo and in vitro results showed IH-induced cardiac fibroblast activation and increased TSP1 expression in cardiac fibroblasts. Mechanistically, phosphorylation of STAT3 at Tyr705 mediated the IH-induced TSP1 expression and fibroblast activation. Finally, STAT3 inhibitor S3I-201 or AAV9 carrying a periostin promoter driving the expression of shRNA targeting Stat3 significantly attenuated the synergistic effects of IH and Ang II on cardiac fibrosis in mice. This work suggests a potential therapeutic strategy for OSA-related fibrotic heart disease.

scholarly journals Mechanical regulation of cardiac fibroblast profibrotic phenotypes

2017 ◽  
Vol 28 (14) ◽  
pp. 1871-1882 ◽  
Author(s):  
Kate M. Herum ◽  
Jonas Choppe ◽  
Aditya Kumar ◽  
Adam J. Engler ◽  
Andrew D. McCulloch
Keyword(s):  
Smooth Muscle ◽  
Cardiac Fibrosis ◽  
Cardiac Fibroblast ◽  
Fiber Formation ◽  
Border Region ◽  
Phenotypic Trait ◽  
Mechanical Stimuli ◽  
Collagen Iii ◽  
Actin Fiber

Cardiac fibrosis is a serious condition currently lacking effective treatments. It occurs as a result of cardiac fibroblast (CFB) activation and differentiation into myofibroblasts, characterized by proliferation, extracellular matrix (ECM) production and stiffening, and contraction due to the expression of smooth muscle α-actin. The mechanical properties of myocardium change regionally and over time after myocardial infarction (MI). Although mechanical cues are known to activate CFBs, it is unclear which specific mechanical stimuli regulate which specific phenotypic trait; thus we investigated these relationships using three in vitro models of CFB mechanical activation and found that 1) paracrine signaling from stretched cardiomyocytes induces CFB proliferation under mechanical conditions similar to those of the infarct border region; 2) direct stretch of CFBs mimicking the mechanical environment of the infarct region induces a synthetic phenotype with elevated ECM production; and 3) progressive matrix stiffening, modeling the mechanical effects of infarct scar maturation, causes smooth muscle α-actin fiber formation, up-regulation of collagen I, and down-regulation of collagen III. These findings suggest that myocyte stretch, fibroblast stretch, and matrix stiffening following MI may separately regulate different profibrotic traits of activated CFBs.

scholarly journals Glycolysis Inhibition Alleviates Cardiac Fibrosis After Myocardial Infarction by Suppressing Cardiac Fibroblast Activation

2021 ◽  
Vol 8 ◽  
Author(s):  
Zhi-Teng Chen ◽  
Qing-Yuan Gao ◽  
Mao-Xiong Wu ◽  
Meng Wang ◽  
Run-Lu Sun ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Western Blot ◽  
Cardiac Fibrosis ◽  
Cardiac Fibroblast ◽  
Rank Test ◽  
Fluorescence Signal ◽  
Fibroblast Activation ◽  
Log Rank Test ◽  
Masson Staining

Objective: To explore the role of glycolysis in cardiac fibroblast (CF) activation and cardiac fibrosis after myocardial infarction (MI).Method:In vivo: 2-Deoxy-D-glucose (2-DG), a glycolysis inhibitor, was injected into the abdominal cavity of the MI or sham mice every day. On the 28th day, cardiac function was measured by ultrasonic cardiography, and the hearts were harvested. Masson staining and immunofluorescence (IF) were used to evaluate the fibrosis area, and western blot was used to identify the glycolytic level. In vitro, we isolated the CF from the sham, MI and MI with 2-DG treatment mice, and we also activated normal CF with transforming growth factor-β1 (TGF-β1) and block glycolysis with 2-DG. We then detected the glycolytic proteins, fibrotic proteins, and the concentrations of lactate and glucose in the culture medium. At last, we further detected the fibrotic and glycolytic markers in human fibrotic and non-fibrotic heart tissues with masson staining, IF and western blot.Result: More collagen and glycolytic protein expressions were observed in the MI mice hearts. The mortality increased when mice were treated with 2-DG (100 mg/kg/d) after the MI surgery (Log-rank test, P < 0.05). When the dosage of 2-DG declined to 50 mg/kg/d, and the treatment was started on the 4th day after MI, no statistical difference of mortality between the two groups was observed (Log-rank test, P = 0.98). The collagen volume fraction was smaller and the fluorescence signal of α-smooth muscle actin (α-SMA) was weaker in mice treated with 2-DG than PBS. In vitro, 2-DG could significantly inhibit the increased expression of both the glycolytic and fibrotic proteins in the activated CF.Conclusion: Cardiac fibrosis is along with the enhancement of CF activation and glycolysis. Glycolysis inhibition can alleviate cardiac fibroblast activation and cardiac fibrosis after myocardial infarction.

Abstract 271: Deletion of Delta-like 1 Homolog Accelerates Fibroblast-myofibroblast Differentiation and Induces Myocardial Fibrosis

2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Luca Troncone ◽  
Patricia Rodriguez ◽  
Yassine Sassi ◽  
Ludovic Benard ◽  
Kiyotake Ishikawa ◽  
...  
Keyword(s):  
Myocardial Fibrosis ◽  
Cardiac Fibrosis ◽  
Cardiac Fibroblasts ◽  
Transmembrane Protein ◽  
Smooth Muscle Actin ◽  
Cardiac Fibroblast ◽  
Myofibroblast Differentiation ◽  
Potential Candidate ◽  
Smad 3

Myocardial fibrosis is associated with profound changes in ventricular architecture and geometry, resulting in diminished cardiac function. Here we uncover that Delta-like homologue 1 (Dlk1), a paternally imprinted gene encoding a transmembrane protein belonging to the Epidermal Growth Factor (EGF)-like family, orchestrates the process of cardiac fibroblast to myofibroblast differentiation and controls myocardial fibrosis. We first show that cardiomyocytes and cardiac fibroblasts express different Dlk1 mRNA spliced variants and its absence accelerates fibroblast differentiation into myofibroblasts in vitro. Overexpression of Dlk1 in cardiac fibroblasts resulted in inhibition of fibroblast proliferation and differentiation into myofibroblasts. This process appears to be regulated by TGFβ-1 signaling, since fibroblasts lacking Dlk1 exhibited a higher activation of the TGFβ-1/Smad-3 pathway at baseline, leading to an earlier acquisition of the myofibroblast phenotype. Dlk1-null mice myocardium displayed increased TGFβ-1/Smad3 profibrotic activity, resulting in infiltration/accumulation of myofibroblasts, and induction and deposition of the extracellular matrix fibronectin extra domain A isoform and collagen, supporting a role for Dlk1 in cardiac fibrosis. Furthermore, these profibrotic events were associated with reduced myofibril integrity, myocyte hypertrophy and cardiac dysfunction. Interestingly, Dlk1 expression was downregulated in ischemic heart tissue from human patients and in the border and scar-zones of infarcted pigs’ hearts. This phenotype was paralleled by increased expression of the profibrotic markers, collagen I, lysyl oxidase and α-smooth muscle actin. Mechanistically, the inhibitory action of Dlk1 on cardiac fibroblast-myofibroblast differentiation is mediated by miR-370 direct targeting of TGFβ-R2/Smad-3 signaling in the myocardium. Given the deleterious effects of continuous activation of this pathway, we propose Dlk1 as a new potential candidate for therapy in cases where aberrant TGFβ signaling leads to chronic fibrosis.

Abstract MP02: Angiotensin II Mediates Microvascular Rarefaction In Vivo and Exacerbates Endothelial-To-Mesenchymal Transition In Vitro

Hypertension ◽  
2015 ◽  
Vol 66 (suppl_1) ◽  
Author(s):  
Katrin Nather ◽  
Mónica Flores-Muñoz ◽  
Rhian M Touyz ◽  
Christopher M Loughrey ◽  
Stuart A Nicklin
Keyword(s):  
Endothelial Cells ◽  
Smooth Muscle ◽  
Cardiac Fibrosis ◽  
Smooth Muscle Actin ◽  
Muscle Actin ◽  
Mesenchymal Transition ◽  
Endothelial To Mesenchymal Transition

Cardiac fibrosis accompanies numerous cardiovascular diseases (CVD) such as hypertension and myocardial infarction and increases myocardial stiffness leading to contractile dysfunction. Recently, endothelial-to-mesenchymal transition (EndMT) has been shown to contribute to myocardial fibrosis. EndMT describes a process by which endothelial cells transform into mesenchymal cells such as fibroblasts and has been implicated in many fibrotic diseases. Angiotensin II (AngII) plays a key role in myocardial fibrosis and has been associated with the activation of fibroblasts to myofibroblasts and an increase in myocardial collagen deposition. Here, we assessed the role of AngII in capillary loss and EndMT in vivo and in vitro . C57BL/6J mice were infused with H 2 O (control) or 24μg/kg/hr AngII for 4 weeks. Mice infused with AngII developed significant cardiac fibrosis characterised by the deposition of collagen I (2.5-fold vs. control; p<0.05) and III (1.9-fold vs. control; p<0.05). Capillary density was assessed by CD31 immunohistochemistry and revealed significant vascular rarefaction (control 2161±111 vs . AngII 838±132 capillaries/mm 2 ; p<0.05). To investigate whether AngII can induce EndMT in vitro , human coronary artery endothelial cells were stimulated with 10ng/mL TGFβ 1 alone or in combination with 1μM AngII for 10 days. AngII significantly enhanced TGFβ 1 -induced gene expression of α-smooth muscle actin (TGFβ 1 1.8-fold; TGFβ 1 ±AngII 4.3-fold vs . control; p<0.05) and collagen I (TGFβ 1 9.2-fold; TGFβ 1 +AngII 30.2-fold vs . control; p<0.05). Concomitantly, AngII significantly increased α-smooth muscle actin protein expression (TGFβ 1 3.9-fold; TGFβ 1 +AngII 23.6-fold vs . control; p<0.05) and significantly decreased CD31 expression (TGFβ 1 0.9-fold; TGFβ 1 +AngII 0.7-fold vs . control; p<0.05), suggesting AngII acts in concert with TGFβ 1 to enhance conversion of endothelial cells to myofibroblasts. Further studies investigating the underlying mechanism, including the role of the Smad pathway, are ongoing. These results demonstrate that AngII induces vascular rarefaction in vivo and potentiates TGFβ 1 -induced EndMT in vitro. Understanding the molecular basis for these observations may help to identify new therapeutic options in CVD.

Abstract 100: Discovery of Cardiac Fibroblast Enriched microRNAs and Their Pivotal Roles in the Regulation of Cardiac Remodeling and Fibrosis

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Yue Zhou ◽  
Arthur M Richards ◽  
Peipei Wang
Keyword(s):  
Cardiac Fibrosis ◽  
Smooth Muscle Actin ◽  
Cardiac Fibroblast ◽  
Tissue Growth ◽  
Functional Study ◽  
Coronary Artery Ligation ◽  
Alpha Smooth Muscle Actin ◽  
Artery Ligation ◽  
Rat Cardiomyocytes

Cardiac fibroblast (cFB) responses to cardiac injury or overload directly contribute to deterioration of cardiac function in heart failure. MicroRNAs (miR) target multiple genes in cell signaling networks and are likely to have pivotal regulatory roles with respect to cFB function. To date cFB enriched miRs have not been reported. We have identified cFB enriched miRs which we hypothesize direct cFB proliferation and differentiation. Neonatal and adult rat cardiomyocytes (CM) and cFBs were isolated and cultured. In vivo and in vitro cardiac ischemic models comprised coronary artery ligation induced myocardial infarction (MI) in rats and cultured cFB exposed to hypoxia. RNA and protein were extracted for miR microarray, qPCR and Western Blot. Adult cFB transfected with miR mimics were tested for CCK-8 proliferation assay. Fifteen dysregulated miRs were selected from array profiles and qPCR validation. Among them miR-31, -199a, -214 and -222 were highly expressed in adult cFBs 10-90 folds vs. CM. CM specific miR-208a and 133a were undetectable in cFB. Neonatal cells showed directionally concordant but less pronounced differences. In early MI, cardiac miR-31 was up-regulated >30 fold vs. Sham (infarct), others increased 6-12 folds. All changes were ranked infarct>border>remote area. As a control, non-cFB enriched miR-125a remained unchanged. Hypoxia treatment of cFB in vitro up-regulated miR-31 but not the other miRs. Functional study by mimic transfection revealed differential roles of the miRs. MiR-31 increased cFB proliferation in CCK8 assay. MiR-199a and -222 had opposite effects. MiR-199a, but not miR-222, reversed the pro-fibrotic effects of TGF-β. MiR-199a reduced mRNA and protein expression of alpha smooth muscle actin (α-SMA), a myoFB differentiation marker and connective tissue growth factor (CTGF), a predicted target (miRDB). Conversely miR-31 increased α-SMA and CTGF. We provide the first report of 4 cFB enriched miRs and demonstrated their pro- vs. anti-fibrotic roles in vitro (miR-31 vs. miR-199 and -222 respectively). In early MI, the increase of pro-fibrotic miR-31 was predominant, whilst other miR dysregulation was secondary to cFB proliferation. cFB enriched miRs determine cFB fate and progression of cardiac fibrosis/remodeling.

scholarly journals Procyanidin B2 Reduces Vascular Calcification through Inactivation of ERK1/2-RUNX2 Pathway

Antioxidants ◽  
2021 ◽  
Vol 10 (6) ◽  
pp. 916
Author(s):  
Yingquan Liang ◽  
Guilan Chen ◽  
Feng Zhang ◽  
Xiaoxiao Yang ◽  
Yuanli Chen ◽  
...  
Keyword(s):  
Smooth Muscle ◽  
Vascular Calcification ◽  
Aortic Root ◽  
Smooth Muscle Actin ◽  
Bone Morphogenetic Protein 2 ◽  
Plaque Burden ◽  
Runx2 Expression ◽  
Plaque Instability ◽  
Related Transcription Factor

Vascular calcification is strongly associated with atherosclerotic plaque burden and plaque instability. The activation of extracellular signal-regulated kinase 1/2 (ERK1/2) increases runt related transcription factor 2 (RUNX2) expression to promote vascular calcification. Procyanidin B2 (PB2), a potent antioxidant, can inhibit ERK1/2 activation in human aortic smooth muscle cells (HASMCs). However, the effects and involved mechanisms of PB2 on atherosclerotic calcification remain unknown. In current study, we fed apoE-deficient (apoE−/−) mice a high-fat diet (HFD) while treating the animals with PB2 for 18 weeks. At the end of the study, we collected blood and aorta samples to determine atherosclerosis and vascular calcification. We found PB2 treatment decreased lesions in en face aorta, thoracic, and abdominal aortas by 21.4, 24.6, and 33.5%, respectively, and reduced sinus lesions in the aortic root by 17.1%. PB2 also increased α-smooth muscle actin expression and collagen content in lesion areas. In the aortic root, PB2 reduced atherosclerotic calcification areas by 75.8%. In vitro, PB2 inhibited inorganic phosphate-induced osteogenesis in HASMCs and aortic rings. Mechanistically, the expression of bone morphogenetic protein 2 and RUNX2 were markedly downregulated by PB2 treatment. Additionally, PB2 inhibited ERK1/2 phosphorylation in the aortic root plaques of apoE−/− mice and calcified HASMCs. Reciprocally, the activation of ERK1/2 phosphorylation by C2-MEK1-mut or epidermal growth factor can partially restore the PB2-inhibited RUNX2 expression or HASMC calcification. In conclusion, our study demonstrates that PB2 inhibits vascular calcification through the inactivation of the ERK1/2-RUNX2 pathway. Our study also suggests that PB2 can be a potential option for vascular calcification treatment.

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