Effects of Sex and 17 β-Estradiol on Cardiac Fibroblast Morphology and Signaling Activities In Vitro

Several studies have demonstrated estrogen’s cardioprotective abilities in decreasing the fibrotic response of cardiac fibroblasts (CFs). However, the majority of these studies are not sex-specific, and those at the cellular level utilize tissue culture plastic, a substrate with a much higher stiffness than physiological conditions. Understanding the intrinsic differences between male and female CFs under more physiologically “healthy” conditions will help to elucidate the divergences in their complex signaling networks. We aimed to do this by conducting a sex-disaggregated analysis of changes in cellular morphology and relative levels of profibrotic signaling proteins in CFs cultured on 8 kPa stiffness plates with and without 17 β-estradiol (E2). Cyclic immunofluorescent analysis indicated that there was a negligible change in cellular morphology due to sex and E2 treatment and that the differences between male and female CFs occur at a biochemical rather than structural level. Several proteins corresponding to profibrotic activity had various sex-specific responses with and without E2 treatment. Single-cell correlation analysis exhibited varied protein–protein interaction across experimental conditions. These findings demonstrate the need for further research into the dimorphisms of male and female CFs to develop better tailored sex-informed prevention and treatment interventions of cardiac fibrosis.

Download Full-text

Effects of Sex and 17β-Estradiol on Cardiac Fibroblast Morphology and Signaling Activities in vitro

10.20944/preprints202109.0110.v1 ◽

2021 ◽

Author(s):

Kelsey Watts ◽

Will Richardson

Keyword(s):

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Cellular Level ◽

Cellular Morphology ◽

Structural Level ◽

Experimental Conditions ◽

Male And Female ◽

Protein Protein Interaction ◽

Complex Signaling

Several studies have demonstrated estrogen’s cardioprotective abilities in decreasing the fibrotic response of cardiac fibroblasts (CFs). However, the majority of these studies are not sex-specific, and those at the cellular level utilize tissue culture plastic, a substrate that has a stiffness much higher than physiological conditions. Understanding the intrinsic differences between male and female CFs under more physiologically “healthy” conditions will help to elucidate the divergences in their complex signaling networks. We aimed to do this by conducting sex-disaggregated analysis of changes in cellular morphology and relative concentrations of profibrotic signaling proteins in CFs cultured on 8kPa stiffness plates with and without 17-β estradiol (E2). Cyclic immunofluorescent analysis indicated that there is a negligible change in cellular morphology due to sex and E2 treatment and that the differences between male and female CFs are occurring at a biochemical rather than structural level. Several proteins corresponding to profibrotic activity had various sex-specific responses with and without E2 treatment. Single-cell correlation analysis exhibited varied protein-protein interaction across experimental conditions. These findings demonstrate the need for further research into the dimorphisms of male and female CFs to develop better tailored, sex-informed prevention and treatment interventions of cardiac fibrosis.

Download Full-text

Up-Regulating Relaxin Expression by G-Quadruplex Interactive Ligand to Achieve Antifibrotic Action

Endocrinology ◽

10.1210/en.2012-1114 ◽

2012 ◽

Vol 153 (8) ◽

pp. 3692-3700 ◽

Cited By ~ 28

Author(s):

Hui-Ping Gu ◽

Sen Lin ◽

Ming Xu ◽

Hai-Yi Yu ◽

Xiao-Jun Du ◽

...

Keyword(s):

Rna Polymerase Ii ◽

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Heart Diseases ◽

Gene Promoter ◽

Binding Motif ◽

Endogenous Expression ◽

G Quadruplex

Myocardial fibrosis is a key pathological change in a variety of heart diseases contributing to the development of heart failure, arrhythmias, and sudden death. Recent studies have shown that relaxin prevents and reverses cardiac fibrosis. Endogenous expression of relaxin was elevated in the setting of heart disease; the extent of such up-regulation, however, is insufficient to exert compensatory actions, and the mechanism regulating relaxin expression is poorly defined. In the rat relaxin-1 (RLN1, Chr1) gene promoter region we found presence of repeated guanine (G)-rich sequences, which allowed formation and stabilization of G-quadruplexes with the addition of a G-quadruplex interactive ligand berberine. The G-rich sequences and the G-quadruplexes were localized adjacent to the binding motif of signal transducer and activator of transcription (STAT)3, which negatively regulates relaxin expression. Thus, we hypothesized that the formation and stabilization of G-quadruplexes by berberine could influence relaxin expression. We found that berberine-induced formation of G-quadruplexes did increase relaxin gene expression measured at mRNA and protein levels. Formation of G-quadruplexes significantly reduced STAT3 binding to the promoter of relaxin gene. This was associated with consequent increase in the binding of RNA polymerase II and STAT5a to relaxin gene promoter. In cardiac fibroblasts and rats treated with angiotensin II, berberine was found to suppress fibroblast activation, collagen synthesis, and extent of cardiac fibrosis through up-regulating relaxin. The antifibrotic action of berberine in vitro and in vivo was similar to that by exogenous relaxin. Our findings document a novel therapeutic strategy for fibrosis through up-regulating expression of endogenous relaxin.

Download Full-text

Abstract 277: Microrna-33 Promotes Cardiac Fibrosis by Maintaining Cellular Lipid Homeostasis

Circulation Research ◽

10.1161/res.119.suppl_1.277 ◽

2016 ◽

Vol 119 (suppl_1) ◽

Author(s):

Masataka Nishiga ◽

Takahiro Horie ◽

Yasuhide Kuwabara ◽

Osamu Baba ◽

Tetsushi Nakao ◽

...

Keyword(s):

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Pressure Overload ◽

Cholesterol Content ◽

Atp Binding Cassette Transporter ◽

Primary Fibroblasts ◽

Proliferation In Vitro ◽

Altered Lipid

Background: A highly conserved microRNA, miR-33 is considered as a potential therapeutic target for atherosclerosis, because recent reports, including ours, indicated miR-33 has atherogenic effects by reducing HDL-C. However, the functions of miR-33 in heart failure remain to be elucidated. Methods and results: To clarify the functions of miR-33 involved in cardiac hypertrophy and fibrosis in vivo, we investigated the responses to pressure overload by transverse aortic constriction (TAC) in miR-33 deficient (KO) mice. When subjected to TAC, miR-33 expression level was significantly up-regulated in wild-type (WT) left ventricles, whereas miR-33 KO hearts displayed no less hypertrophic responses than WT hearts. However, interestingly, histological and gene expression analyses showed ameliorated cardiac fibrosis in miR-33 KO hearts compared to WT hearts. Furthermore, we generated cardiac fibroblast specific miR-33 deficient mice, which also showed ameliorated cardiac fibrosis when they were subjected to TAC. We also found that cardiac fibroblasts were mainly responsible for miR-33 expression in the heart, because its expression was about 4-folds higher in isolated primary cardiac fibroblasts than cardiomyocytes. Deficiency of miR-33 impaired cell proliferation in primary fibroblasts, which was considered due to altered lipid raft cholesterol content by up-regulated ATP-binding cassette transporter A1/G1. Conclusion: Deficiency of miR-33 impaired fibroblast proliferation in vitro, and ameliorated cardiac fibrosis induced by pressure overload in vivo.

Download Full-text

Abstract 292: TRPA1 Promoting Myofibroblast Differentiation Mediate Pressure Overload-Induced Cardiac Fibrosis

Circulation ◽

10.1161/circ.138.suppl_2.292 ◽

2018 ◽

Vol 138 (Suppl_2) ◽

Author(s):

Shuang Li ◽

Dong Han ◽

Dachun Yang

Keyword(s):

Knockout Mice ◽

Molecular Mechanisms ◽

Cardiac Fibrosis ◽

Transient Receptor Potential ◽

Transforming Growth Factor ◽

Ventricular Remodeling ◽

Cardiac Fibroblasts ◽

Gene Transfection ◽

Pressure Overload

Background: Hypertensive ventricular remodeling is a common cause of heart failure. Activation and accumulation of cardiac fibroblasts is the key contributors to this progression. Our previous studies indicate that transient receptor potential ankyrin 1 (TRPA1), a Ca 2+ channel necessary and sufficient, play a prominent role in ventricular remodeling. However, the molecular mechanisms regulating remain poorly understood. Methods: We used TRPA1 agonists cinnamaldehyde (CA) pretreatment and TRPA1 knockout mice to understand the role of TRPA1 in ventricular remodeling of hypertensive heart. We also examine the mechanisms through gene transfection and in vitro experiments. Results: TRPA1 overexpression fully activated myofibroblast transformation, while fibroblasts lacking TRPA1 were refractory to transforming growth factor β (TGF-β) -induced transdifferentiation. TRPA1 knockout mice showed hypertensive ventricular remodeling reversal following pressure overload. We found that the TGF-β induced TRPA1 expression through calcineurin-NFAT-Dyrk1A signaling pathway via the TRPA1 promoter. Once induced, TRPA1 activates the Ca 2+ -responsive protein phosphatase calcineurin, which itself induced myofibroblast transdifferentiation. Moreover, inhibition of calcineurin prevented TRPA1-dependent transdifferentiation. Conclusion: Our study provides the first evidence that TRPA1 regulation in cardiac fibroblasts transformation in response to hypertensive stimulation. The results suggesting a comprehensive pathway for myofibroblast formation in conjunction with TGF-β, Calcineurin, NFAT and Dyrk1A. Furthermore, these data indicate that negative modulation of cardiac fibroblast TRPA1 may represent a therapeutic strategy against hypertensive cardiac remodeling.

Download Full-text

Abstract 782: Fra2 Mediates Oxygen-induced TGFbeta-1 mRNA Expression In Adult Cardiac Fibroblasts: Significance In Myocardial Fibrosis Following Ischemia-reperfusion Injury

Circulation ◽

10.1161/circ.116.suppl_16.ii_150-c ◽

2007 ◽

Vol 116 (suppl_16) ◽

Author(s):

Sashwati Roy ◽

Savita Khanna ◽

Chandan K Sen

Keyword(s):

Mrna Expression ◽

Transforming Growth Factor Beta ◽

Cardiac Fibrosis ◽

Transforming Growth Factor ◽

Ischemia Reperfusion Injury ◽

Cardiac Fibroblasts ◽

Ischemia Reperfusion ◽

Luciferase Reporter ◽

Mrna Levels

Background . Transforming growth factor beta-1 (TGFbeta-1) is a key cytokine implicated in the development of cardiac fibrosis following ischemia-reperfusion (IR) injury. The profibrotic effects of TGFbeta-1 are primarily attributable to the differentiation of cardiac fibroblasts (CF) to myofibroblasts. Previously, we have reported perceived hyperoxia (Circ Res 92:264 –71), sub-lethal reoxygenation shock during IR, induces differentiation of CF to myofibroblasts at the infarct site. The mechanisms underlying oxygen-sensitive induction of TGFbeta-1 mRNA remain to be characterized. Hypothesis . Fra2 mediates oxygen-induced TGFbeta-1 mRNA expression in adult cardiac fibroblasts. Methods. TGFbeta-1 mRNA expression in infarct tissue was investigated in an IR injury model. The left anterior descending coronary artery of mice was transiently occluded for 60 minutes followed by reperfusion to induce IR injury. Spatially resolved infarct and non-infarct tissues were collected at 0, 1, 3, 5, and 7 days post-IR using laser capture microdissection. TGFbeta-1 mRNA levels were measured using real-time PCR. To investigate the role of oxygen in the regulation of TGFbeta-1, we used our previously reported model of perceived hyperoxia where CF (from 5wks old mice) after isolation were cultured at 5%O 2 (physiological pO 2 ) followed by transferring them to 20%O 2 to induce hyperoxic insult. Results & Conclusions. In vivo, a significant increase (p<0.01; n=5) in TGFbeta-1 mRNA was observed at the infarct site already at day 1 post-IR. The levels continued to increase until day 7 post-IR. In vitro, exposure of CF to 20%O 2 hyperoxic insult induced TGFbeta-1 mRNA (p<0.001; n=4) and protein (p<0.01; n=4) expression. Using a TGFbeta-1 promoter-luciferase reporter and DNA binding assays, we collected first evidence that AP-1 and its component Fra2 as major mediators of oxygen-induced TGFbeta-1 expression. Exposure to 20%O 2 resulted in increased localization of Fra2 in nucleus. siRNA-dependent Fra-2 knock-down completely abrogated oxygen-induced TGFbeta1 expression. In conclusion, this study presents first evidence that Fra-2 is involved in inducible TGFbeta1 expression in CF. Fra2 was noted as being central in regulating oxygen-induced TGFbeta-1 expression.s

Download Full-text

Abstract 445: A Pro-Fibrotic Role of Interleukin-4 in Cardiac Remodeling and Dysfunction

Hypertension ◽

10.1161/hyp.64.suppl_1.445 ◽

2014 ◽

Vol 64 (suppl_1) ◽

Author(s):

Hongmei Peng ◽

Oscar Carretero ◽

Xiao-Ping Yang ◽

Pablo Nakagawa ◽

Jiang Xu ◽

...

Keyword(s):

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Interleukin 4 ◽

Ang Ii ◽

Collagen Production ◽

And Function ◽

First Time ◽

Mini Pump

Elevated interleukin-4 (IL-4) levels are positively related to cardiac fibrosis in heart failure and hypertension. Using Balb/c exhibiting high circulating IL-4, Balb/c- Il4 tm2Nnt (IL-4 knockout with Balb/c background, IL-4 -/- ) and C57BL/6 mice, as well as cultured cardiac fibroblasts (CFs), we hypothesized that 1) high levels of IL-4 result in cardiac fibrosis, making the heart susceptible to angiotensin II (Ang II)-induced damage, and 2) IL-4 potently stimulates collagen production by CFs. Each strain (9- to 12-week old male) received vehicle or Ang II (1.4 mg/kg/day, s.c. via osmotic mini-pump) for 8 weeks. Cardiac fibrosis and function were determined by histology and echocardiography, respectively. Compared to C57BL/6, Balb/c mice had doubled interstitial collagen in the heart, enlarged left ventricle and decreased cardiac function along with elevated cardiac IL-4 protein (1.00±0.08 in C57BL/6 vs 2.61±0.46 in Balb/c, p <0.05); all those changes were significantly attenuated in IL-4 -/- (Table 1). Ang II further deteriorated cardiac fibrosis and dysfunction in Balb/c; these detrimental effects were attenuated in IL-4 -/- , although the three strains had a similar level of hypertension. In vitro study revealed that IL-4Rα was constitutively expressed in CFs (Western blot), and IL-4 potently stimulated collagen production by CFs (hydroxproline assay, from 18.89±0.85 to 38.81±3.61 μg/mg at 10 ng/ml, p <0.01). Our study demonstrates for the first time that IL-4, as a potent pro-fibrotic cytokine in the heart, contributes to cardiac fibrotic remodeling and dysfunction. Thus IL-4 may be a potential therapeutic target for cardiac fibrosis and dysfunction.

Download Full-text

Novel role for cardiac myocyte-derived β-2 microglobulin in mediating cardiac fibrosis

Clinical Science ◽

10.1042/cs20180681 ◽

2018 ◽

Vol 132 (19) ◽

pp. 2117-2120

Author(s):

Michael J. Boyer ◽

Satoru Eguchi

Keyword(s):

Cardiac Fibrosis ◽

Cardiac Myocyte ◽

Cardiac Fibroblasts ◽

Significant Risk ◽

Growth Factor Receptor ◽

Pressure Overload ◽

Significant Risk Factor ◽

Cardiac Complications

Hypertension is a significant risk factor for the development of cardiovascular ailments, including ischemic heart disease and diastolic dysfunction. In a recent issue of Clinical Science, Li et al. [Clin. Sci. (2018) 132, 1855–1874] report that β-2 microglobulin (β2M) is a novel secreted soluble factor released by cardiac myocytes during pressure overload that promotes profibrotic gene expression in cardiac fibroblasts both in vitro and in vivo. Their study further identifies elevated β2M levels as a possible biomarker for hypertensive patients with cardiac complications. The authors propose a mechanism that mechanically stretched cardiomyocytes release soluble β2M which, through paracrine communication with cardiac fibroblasts, transactivates epidermal growth factor receptor (EGFR) to initiate acute signal transduction and up-regulate profibrotic genes, thereby promoting fibrosis. Here, we will discuss the background, significance of the study, alternative mechanisms, and future directions.

Download Full-text

Downregulation of S100A4 Alleviates Cardiac Fibrosis via Wnt/β -Catenin Pathway in Mice

Cellular Physiology and Biochemistry ◽

10.1159/000489683 ◽

2018 ◽

Vol 46 (6) ◽

pp. 2551-2560 ◽

Cited By ~ 12

Author(s):

LiJun Qian ◽

Jian Hong ◽

YanMei Zhang ◽

MengLin Zhu ◽

XinChun Wang ◽

...

Keyword(s):

Calcium Binding ◽

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Group A ◽

Ischemic Diseases ◽

Fibrotic Diseases ◽

Signaling Activation

Background/Aims: Cardiac fibrosis is a pathological change leading to cardiac remodeling during the progression of myocardial ischemic diseases, and its therapeutic strategy remains to be explored. S100A4, a calcium-binding protein, participates in fibrotic diseases with an unclear mechanism. This study aimed to investigate the role of S100A4 in cardiac fibrosis. Methods: Cardiac fibroblasts from neonatal C57BL/6 mouse hearts were isolated and cultured. Myocardial infarction was induced by ligating the left anterior descending coronary artery (LAD). The ligation was not performed in the sham group. A volume of 5×105pfu/g adenovirus or 5 µM/g ICG-001 was intramyocardially injected into five parts bordering the infarction zone or normal region. We used Western blotting, quantitative RT-PCR, immunofluorescence, immunohistochemistry and Masson’s trichrome staining to explore the function of S100A4. Results: We found significant increases of S100A4 level and cardiac fibrosis markers, and β-catenin signaling activation in vitro and in vivo. In addition, knockdown of S100A4 significantly reduced cardiac fibrosis and β-catenin levels. Moreover, the expression of S100A4 decreased after ICG-001 inhibited β-catenin signal pathway. Conclusion: Downregulation of S100A4 alleviates cardiac fibrosis via Wnt/β -catenin pathway in mice. S100A4 may be a therapeutic target of cardiac fibrosis.

Download Full-text

Evolutionary diversification of protein–protein interactions by interface add-ons

Proceedings of the National Academy of Sciences ◽

10.1073/pnas.1707335114 ◽

2017 ◽

Vol 114 (40) ◽

pp. E8333-E8342 ◽

Cited By ~ 13

Author(s):

Maximilian G. Plach ◽

Florian Semmelmann ◽

Florian Busch ◽

Markus Busch ◽

Leonhard Heizinger ◽

...

Keyword(s):

Protein Interaction ◽

Protein Interactions ◽

Protein Complexes ◽

Evolutionary Strategy ◽

Structural Level ◽

Protein Protein Interactions ◽

Protein Protein Interaction ◽

Evolutionary Diversification

Cells contain a multitude of protein complexes whose subunits interact with high specificity. However, the number of different protein folds and interface geometries found in nature is limited. This raises the question of how protein–protein interaction specificity is achieved on the structural level and how the formation of nonphysiological complexes is avoided. Here, we describe structural elements called interface add-ons that fulfill this function and elucidate their role for the diversification of protein–protein interactions during evolution. We identified interface add-ons in 10% of a representative set of bacterial, heteromeric protein complexes. The importance of interface add-ons for protein–protein interaction specificity is demonstrated by an exemplary experimental characterization of over 30 cognate and hybrid glutamine amidotransferase complexes in combination with comprehensive genetic profiling and protein design. Moreover, growth experiments showed that the lack of interface add-ons can lead to physiologically harmful cross-talk between essential biosynthetic pathways. In sum, our complementary in silico, in vitro, and in vivo analysis argues that interface add-ons are a practical and widespread evolutionary strategy to prevent the formation of nonphysiological complexes by specializing protein–protein interactions.

Download Full-text

Synthesis and Biological Evaluation of Novel Thiazolyl-Coumarin Derivatives as Potent Histone Deacetylase Inhibitors with Antifibrotic Activity

Molecules ◽

10.3390/molecules24040739 ◽

2019 ◽

Vol 24 (4) ◽

pp. 739 ◽

Cited By ~ 2

Author(s):

Viviana Pardo-Jiménez ◽

Patricio Navarrete-Encina ◽

Guillermo Díaz-Araya

Keyword(s):

Histone Deacetylases ◽

Histone Deacetylase Inhibitors ◽

Cardiac Fibrosis ◽

Cardiac Fibroblasts ◽

Hdac Inhibitors ◽

Biological Evaluation ◽

Neonatal Rat ◽

Zinc Binding ◽

Coumarin Derivatives

New histone deacetylases (HDAC) inhibitors with low toxicity to non-cancerous cells, are a prevalent issue at present because these enzymes are actively involved in fibrotic diseases. We designed and synthesized a novel series of thiazolyl-coumarins, substituted at position 6 (R = H, Br, OCH3), linked to classic zinc binding groups, such as hydroxamic and carboxylic acid moieties and alternative zinc binding groups such as disulfide and catechol. Their in vitro inhibitory activities against HDACs were evaluated. Disulfide and hydroxamic acid derivatives were the most potent ones. Assays with neonatal rat cardiac fibroblasts demonstrated low cytotoxic effects for all compounds. Regarding the parameters associated to cardiac fibrosis development, the compounds showed antiproliferative effects, and triggered a strong decrease on the expression levels of both α-SMA and procollagen I. In conclusion, the new thiazolyl-coumarin derivatives inhibit HDAC activity and decrease profibrotic effects on cardiac fibroblasts.

Download Full-text