scholarly journals Dye-Mediated Photo-Oxidation Biomaterial Fixation: Analysis of Bioinductivity and Mechanical Properties of Bovine Pericardium for Use in Cardiac Surgery

2021 ◽  
Vol 22 (19) ◽  
pp. 10768
Author(s):  
Simranjit S. Pattar ◽  
Vishnu Vasanthan ◽  
Guoqi Teng ◽  
Karl T. Wagner ◽  
Kristina Jeon ◽  
...  
Keyword(s):  
Cardiac Surgery ◽  
Cardiac Fibroblasts ◽  
Tensile Force ◽  
Biomechanical Testing ◽  
Biomechanical Properties ◽  
Cardiac Fibroblast ◽  
Bovine Pericardium ◽  
Cellular Mechanisms ◽  
Photo Oxidation ◽  
Human Cardiac Fibroblasts

Extracellular matrix bioscaffolds can influence the cardiac microenvironment and modulate endogenous cellular mechanisms. These materials can optimize cardiac surgery for repair and reconstruction. We investigated the biocompatibility and bioinductivity of bovine pericardium fixed via dye-mediated photo-oxidation on human cardiac fibroblast activity. We compared a dye-mediated photo-oxidation fixed bioscaffold to glutaraldehyde-fixed and non-fixed bioscaffolds reported in contemporary literature in cardiac surgery. Human cardiac fibroblasts from consenting patients were seeded on to bioscaffold materials to assess the biocompatibility and bioinductivity. Human cardiac fibroblast gene expression, secretome, morphology and viability were studied. Dye-mediated photo-oxidation fixed acellular bovine pericardium preserves human cardiac fibroblast phenotype and viability; and potentiates a pro-vasculogenic paracrine response. Material tensile properties were compared with biomechanical testing. Dye-mediated photo-oxidation fixed acellular bovine pericardium had higher compliance compared to glutaraldehyde-fixed bioscaffold in response to tensile force. The biocompatibility, bioinductivity, and biomechanical properties of dye-mediated photo-oxidation fixed bovine pericardium demonstrate its feasibility as a bioscaffold for use in cardiac surgery. As a fixed yet bioinductive solution, this bioscaffold demonstrates enhanced compliance and retains bioinductive properties that may leverage endogenous reparative pathways. Dye-mediated photo-oxidation fixed bioscaffold warrants further investigation as a viable tool for cardiac repair and reconstruction.

scholarly journals Soluble St2 Induces Cardiac Fibroblast Activation and Collagen Synthesis via Neuropilin-1

Cells ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 1667 ◽  
Author(s):  
Lara Matilla ◽  
Vanessa Arrieta ◽  
Eva Jover ◽  
Amaia Garcia-Peña ◽  
Ernesto Martinez-Martinez ◽  
...  
Keyword(s):  
Collagen Synthesis ◽  
Cardiac Fibrosis ◽  
Transforming Growth Factor ◽  
Cardiac Fibroblasts ◽  
Interleukin 1 ◽  
Cardiac Fibroblast ◽  
Pathogenic Role ◽  
Fibroblast Activation ◽  
Neuropilin 1 ◽  
Human Cardiac Fibroblasts

Circulating levels of soluble interleukin 1 receptor-like 1 (sST2) are increased in heart failure and associated with poor outcome, likely because of the activation of inflammation and fibrosis. We investigated the pathogenic role of sST2 as an inductor of cardiac fibroblasts activation and collagen synthesis. The effects of sST2 on human cardiac fibroblasts was assessed using proteomics and immunodetection approaches to evidence the upregulation of neuropilin-1 (NRP-1), a regulator of the profibrotic transforming growth factor (TGF)-β1. In parallel, sST2 increased fibroblast activation, collagen and fibrosis mediators. Pharmacological inhibition of nuclear factor-kappa B (NF-κB) restored NRP-1 levels and blocked profibrotic effects induced by sST2. In NRP-1 knockdown cells, sST2 failed to induce fibroblast activation and collagen synthesis. Exogenous NRP-1 enhanced cardiac fibroblast activation and collagen synthesis via NF-κB. In a pressure overload rat model, sST2 was elevated in association with cardiac fibrosis and was positively correlated with NRP-1 expression. Our study shows that sST2 induces human cardiac fibroblasts activation, as well as the synthesis of collagen and profibrotic molecules. These effects are mediated by NRP-1. The blockade of NF-κB restored NRP-1 expression, improving the profibrotic status induced by sST2. These results show a new pathogenic role for sST2 and its mediator, NRP-1, as cardiac fibroblast activators contributing to cardiac fibrosis.

scholarly journals Altered Expression of ORAI and STIM Isoforms in Activated Human Cardiac Fibroblasts

2021 ◽  
pp. S21-S30
Author(s):  
R. Čendula ◽  
N. Chomaničová ◽  
A. Adamičková ◽  
A. Gažová ◽  
J. Kyselovič ◽  
...  
Keyword(s):  
Cell Culture ◽  
Cardiac Fibroblasts ◽  
Collagen Content ◽  
Mrna Levels ◽  
Cellular Mechanisms ◽  
Altered Expression ◽  
Human Cardiac Fibroblasts ◽  
Collagen Genes ◽  
Molecular Components ◽  
Cell Medium

Cardiac fibrotization is a well-known process characteristic of many cardiac pathological conditions. The key element is excessive activation of cardiac fibroblasts, their transdifferentiation into myofibroblasts, increased production, and accumulation of extracellular matrix proteins, resulting in cardiac stiffness. The exact cellular mechanisms and molecular components involved in the process are not fully elucidated, but the SOCE mechanism could play an important role. Its key molecules are the molecular sensor of calcium in ER/SR – STIM and the highly selective calcium channels Orai located in the plasma membrane. This study aims to evaluate selected SOCE-associated genes in the activation of HCF cell culture by several known substances (phenylephrine, isoprenaline) that represent cardiovascular overload. After cell cultivation, cell medium was collected to measure the soluble collagen content. From the harvested cells, qRT-PCR was performed to determine the mRNA levels of the corresponding genes. The activation of cells was based on changes in the relative expression of collagen genes as well as the collagen content in the medium of the cell culture. We detected an increase in the expression of the Orai2 isoform, a change in the Orai1/Orai3 ratio and also an increase in the expression of the STIM2 isoform. These results suggest an increased activation of the SOCE mechanism under stress conditions of fibroblasts, which supports the hypothesis of fibroblast activation in pathological processes by altering calcium homeostasis through the SOCE mechanism.

scholarly journals SKI activates the Hippo pathway via LIMD1 to inhibit cardiac fibroblast activation

2021 ◽  
Vol 116 (1) ◽  
Author(s):  
Natalie M. Landry ◽  
Sunil G. Rattan ◽  
Krista L. Filomeno ◽  
Thomas W. Meier ◽  
Simon C. Meier ◽  
...  
Keyword(s):  
Cardiac Fibroblasts ◽  
Cardiac Fibroblast ◽  
Negative Regulator ◽  
Expression Vectors ◽  
Cell Phenotype ◽  
Hippo Signaling ◽  
Fibroblast Activation ◽  
Elastic Substrates ◽  
Human Cardiac Fibroblasts

AbstractWe have previously shown that overexpression of SKI, an endogenous TGF-β1 repressor, deactivates the pro-fibrotic myofibroblast phenotype in the heart. We now show that SKI also functions independently of SMAD/TGF-β signaling, by activating the Hippo tumor-suppressor pathway and inhibiting the Transcriptional co-Activator with PDZ-binding motif (TAZ or WWTR1). The mechanism(s) by which SKI targets TAZ to inhibit cardiac fibroblast activation and fibrogenesis remain undefined. A rat model of post-myocardial infarction was used to examine the expression of TAZ during acute fibrogenesis and chronic heart failure. Results were then corroborated with primary rat cardiac fibroblast cell culture performed both on plastic and on inert elastic substrates, along with the use of siRNA and adenoviral expression vectors for active forms of SKI, YAP, and TAZ. Gene expression was examined by qPCR and luciferase assays, while protein expression was examined by immunoblotting and fluorescence microscopy. Cell phenotype was further assessed by functional assays. Finally, to elucidate SKI’s effects on Hippo signaling, the SKI and TAZ interactomes were captured in human cardiac fibroblasts using BioID2 and mass spectrometry. Potential interactors were investigated in vitro to reveal novel mechanisms of action for SKI. In vitro assays on elastic substrates revealed the ability of TAZ to overcome environmental stimuli and induce the activation of hypersynthetic cardiac myofibroblasts. Further cell-based assays demonstrated that SKI causes specific proteasomal degradation of TAZ, but not YAP, and shifts actin cytoskeleton dynamics to inhibit myofibroblast activation. These findings were supported by identifying the bi-phasic expression of TAZ in vivo during post-MI remodeling and fibrosis. BioID2-based interactomics in human cardiac fibroblasts suggest that SKI interacts with actin-modifying proteins and with LIM Domain-containing protein 1 (LIMD1), a negative regulator of Hippo signaling. Furthermore, we found that LATS2 interacts with TAZ, whereas LATS1 does not, and that LATS2 knockdown prevented TAZ downregulation with SKI overexpression. Our findings indicate that SKI’s capacity to regulate cardiac fibroblast activation is mediated, in part, by Hippo signaling. We postulate that the interaction between SKI and TAZ in cardiac fibroblasts is arbitrated by LIMD1, an important intermediary in focal adhesion-associated signaling pathways. This study contributes to the understanding of the unique physiology of cardiac fibroblasts, and of the relationship between SKI expression and cell phenotype.

scholarly journals Diastolic dysfunction in a pre-clinical model of diabetes is associated with changes in the cardiac non-myocyte cellular composition

2021 ◽  
Vol 20 (1) ◽  
Author(s):  
Charles D. Cohen ◽  
Miles J. De Blasio ◽  
Man K. S. Lee ◽  
Gabriella E. Farrugia ◽  
Darnel Prakoso ◽  
...  
Keyword(s):  
Bone Marrow ◽  
Flow Cytometry ◽  
Diastolic Dysfunction ◽  
Systolic Function ◽  
Cardiac Fibroblasts ◽  
Detailed Examination ◽  
Diabetic Mice ◽  
Cellular Mechanisms ◽  
Clinical Model ◽  
Cardiac Ventricles

Abstract Background Diabetes is associated with a significantly elevated risk of cardiovascular disease and its specific pathophysiology remains unclear. Recent studies have changed our understanding of cardiac cellularity, with cellular changes accompanying diabetes yet to be examined in detail. This study aims to characterise the changes in the cardiac cellular landscape in murine diabetes to identify potential cellular protagonists in the diabetic heart. Methods Diabetes was induced in male FVB/N mice by low-dose streptozotocin and a high-fat diet for 26-weeks. Cardiac function was measured by echocardiography at endpoint. Flow cytometry was performed on cardiac ventricles as well as blood, spleen, and bone-marrow at endpoint from non-diabetic and diabetic mice. To validate flow cytometry results, immunofluorescence staining was conducted on left-ventricles of age-matched mice. Results Mice with diabetes exhibited hyperglycaemia and impaired glucose tolerance at endpoint. Echocardiography revealed reduced E:A and e’:a’ ratios in diabetic mice indicating diastolic dysfunction. Systolic function was not different between the experimental groups. Detailed examination of cardiac cellularity found resident mesenchymal cells (RMCs) were elevated as a result of diabetes, due to a marked increase in cardiac fibroblasts, while smooth muscle cells were reduced in proportion. Moreover, we found increased levels of Ly6Chi monocytes in both the heart and in the blood. Consistent with this, the proportion of bone-marrow haematopoietic stem cells were increased in diabetic mice. Conclusions Murine diabetes results in distinct changes in cardiac cellularity. These changes—in particular increased levels of fibroblasts—offer a framework for understanding how cardiac cellularity changes in diabetes. The results also point to new cellular mechanisms in this context, which may further aid in development of pharmacotherapies to allay the progression of cardiomyopathy associated with diabetes.

scholarly journals A protocol for transdifferentiation of human cardiac fibroblasts into endothelial cells via activation of innate immunity

2021 ◽  
Vol 2 (2) ◽  
pp. 100556
Author(s):  
Chun Liu ◽  
Pedro Medina ◽  
Dilip Thomas ◽  
Ian Y. Chen ◽  
Karim Sallam ◽  
...  
Keyword(s):  
Innate Immunity ◽  
Endothelial Cells ◽  
Cardiac Fibroblasts ◽  
Human Cardiac Fibroblasts

scholarly journals Recent Advances in Single-Cell Profiling and Multispecific Therapeutics: Paving the Way for a New Era of Precision Medicine Targeting Cardiac Fibroblasts

2021 ◽  
Vol 23 (7) ◽  
Author(s):  
Sally Yu Shi ◽  
Xin Luo ◽  
Tracy M. Yamawaki ◽  
Chi-Ming Li ◽  
Brandon Ason ◽  
...  
Keyword(s):  
Heart Failure ◽  
Precision Medicine ◽  
Single Cell ◽  
Cardiac Fibroblasts ◽  
Rapid Development ◽  
Cardiac Fibroblast ◽  
New Era ◽  
Fibroblast Activation ◽  
Cell Gene Expression ◽  
The Way

Abstract Purpose of Review Cardiac fibroblast activation contributes to fibrosis, maladaptive remodeling and heart failure progression. This review summarizes the latest findings on cardiac fibroblast activation dynamics derived from single-cell transcriptomic analyses and discusses how this information may aid the development of new multispecific medicines. Recent Findings Advances in single-cell gene expression technologies have led to the discovery of distinct fibroblast subsets, some of which are more prevalent in diseased tissue and exhibit temporal changes in response to injury. In parallel to the rapid development of single-cell platforms, the advent of multispecific therapeutics is beginning to transform the biopharmaceutical landscape, paving the way for the selective targeting of diseased fibroblast subpopulations. Summary Insights gained from single-cell technologies reveal critical cardiac fibroblast subsets that play a pathogenic role in the progression of heart failure. Combined with the development of multispecific therapeutic agents that have enabled access to previously “undruggable” targets, we are entering a new era of precision medicine.

Effects of methylglyoxal on human cardiac fibroblast: roles of transient receptor potential ankyrin 1 (TRPA1) channels

2014 ◽  
Vol 307 (9) ◽  
pp. H1339-H1352 ◽  
Author(s):  
Gaku Oguri ◽  
Toshiaki Nakajima ◽  
Yumiko Yamamoto ◽  
Nami Takano ◽  
Tomofumi Tanaka ◽  
...  
Keyword(s):  
Cell Cycle ◽  
Diabetic Cardiomyopathy ◽  
Cell Cycle Progression ◽  
Transient Receptor Potential ◽  
Cardiac Fibroblasts ◽  
Receptor Potential ◽  
Rt Pcr ◽  
Cycle Progression ◽  
Transient Receptor ◽  
Human Cardiac Fibroblasts

Cardiac fibroblasts contribute to the pathogenesis of cardiac remodeling. Methylglyoxal (MG) is an endogenous carbonyl compound produced under hyperglycemic conditions, which may play a role in the development of pathophysiological conditions including diabetic cardiomyopathy. However, the mechanism by which this occurs and the molecular targets of MG are unclear. We investigated the effects of MG on Ca2+ signals, its underlying mechanism, and cell cycle progression/cell differentiation in human cardiac fibroblasts. The conventional and quantitative real-time RT-PCR, Western blot, immunocytochemical analysis, and intracellular Ca2+ concentration [Ca2+]i measurement were applied. Cell cycle progression was assessed using the fluorescence activated cell sorting. MG induced Ca2+ entry concentration dependently. Ruthenium red (RR), a general cation channel blocker, and HC030031 , a selective transient receptor potential ankyrin 1 (TRPA1) antagonist, inhibited MG-induced Ca2+ entry. Treatment with aminoguanidine, a MG scavenger, also inhibited it. Allyl isothiocyanate, a selective TRPA1 agonist, increased Ca2+ entry. The use of small interfering RNA to knock down TRPA1 reduced the MG-induced Ca2+ entry as well as TRPA1 mRNA expression. The quantitative real-time RT-PCR analysis showed the prominent existence of TRPA1 mRNA. Expression of TRPA1 protein was confirmed by Western blotting and immunocytochemical analyses. MG promoted cell cycle progression from G0/G1 to S/G2/M, which was suppressed by HC030031 or RR. MG also enhanced α-smooth muscle actin expression. The present results suggest that methylglyoxal activates TRPA1 and promotes cell cycle progression and differentiation in human cardiac fibroblasts. MG might participate the development of pathophysiological conditions including diabetic cardiomyopathy via activation of TRPA1.

Abstract 372: The Smad3 Pathway Critically Regulates Myofibroblast Proliferation And Synthetic Activity In Healing Myocardial Infarcts

Circulation ◽  
2008 ◽  
Vol 118 (suppl_18) ◽  
Author(s):  
Marcin Dobaczewski ◽  
Marcin Bujak ◽  
Carlos Gonzalez ◽  
Na Li ◽  
Xiao-Fan Wang ◽  
...  
Keyword(s):  
Myocardial Infarction ◽  
Extracellular Matrix ◽  
Proliferative Activity ◽  
Essential Role ◽  
Cardiac Fibroblasts ◽  
Cardiac Fibroblast ◽  
Synthetic Activity ◽  
Dependent Manner ◽  
Tenascin C ◽  
Infarcted Heart

We have recently demonstrated that the Transforming Growth Factor (TGF)-β/Smad3 pathway is activated in healing infarcts and plays an essential role in the pathogenesis of cardiac remodeling. Smad3 −/− mice were protected from the development of ventricular dilation following infarction and exhibited markedly reduced fibrosis of the peri-infarct area and the remodeling non-infarcted heart. Accordingly, we hypothesized that Smad3 signaling plays an essential role in regulating cardiac fibroblast function and gene expression in myocardial infarction. Surprisingly, Smad3 −/− infarcts exhibited increased peak infiltration with myofibroblasts, associated with evidence of enhanced proliferative activity. Smad3 −/− mice had a higher density of Ki-67-positive proliferating myofibroblasts in the infarcted myocardium in comparison with wildtype (WT) animals (Smad3−/− 917±291 cells/mm 2 vs. WT 614±115 cells/mm 2 , p<0.05). In vitro experiments suggested that TGF-β inhibits murine cardiac fibroblast proliferation in a concentration-dependent manner and that the antiproliferative effects of TGF-β are abrogated in Smad3 −/− fibroblasts. On the other hand Smad3 signaling was essential for extracellular matrix protein synthesis by cardiac fibroblasts. TGF-β-mediated induction of procollagen type III and of the matricellular protein tenascin-C in cardiac fibroblasts was dependent on Smad3. In addition, TGF-β-induced Tissue Inhibitor of Metalloproteinases (TIMP)-1 and -2 upregulation was also abrogated in Smad3 −/− fibroblasts, suggesting that Smad3 signaling regulates matrix metabolism. In vivo, Smad3 −/− infarcts exhibited attenuated tenascin-C and collagen deposition in the infarct and in the remodeling non-infarcted heart. Our findings suggest that the Smad3 pathway critically regulates fibroblast function in healing myocardial infarction. In Smad3 −/− mice, the healing infarct contains abundant myofibroblasts that exhibit enhanced proliferative activity, but have markedly decreased ability to synthesize extracellular matrix proteins and to produce TIMPs. In the absence of Smad3, attenuated matrix deposition in the remodeling non-infarcted heart results in decreased dilation and ameliorated diastolic dysfunction. This research has received full or partial funding support from the American Heart Association, AHA South Central Affiliate (Arkansas, New Mexico, Oklahoma & Texas).

CORRELATION STUDY BETWEEN BONE MINERAL DENSITY DETERMINED BY RADIOGRAPHIC ABSORPTIOMETRY AND BONE RESISTANCE OF EQUINE THIRD METACARPAL BONE SUBMITTED TO BIOMECHANICAL TESTING

2012 ◽  
Vol 15 (01) ◽  
pp. 1250007
Author(s):  
Paulo J R Frazao ◽  
Rodrigo Crispim ◽  
Cesar A M Pereira ◽  
Mariana B Selim ◽  
Lara L Facó ◽  
...  
Keyword(s):  
Bone Mineral Density ◽  
Bone Mineral ◽  
Biomechanical Testing ◽  
Biomechanical Properties ◽  
Correlation Study ◽  
Metacarpal Bone ◽  
Mineral Density ◽  
Radiographic Absorptiometry ◽  
Study Bone Mineral Density ◽  
Significant Linear Correlation

Knowledge about non-invasive methods for early diagnostics in equine orthopedic disorders is economically important and has been widely studied. In this study, bone mineral density determined by radiographic absorptiometry was correlated to bone resistance of the equine third metacarpal bone submitted to biomechanical testing. Thirty pairs of third metacarpal bone of adult horses were collected, dissected, radiographed, analyzed by the radiographic absorptiometry technique, and submitted to tomographic study and biomechanical testing. No significant linear correlation between radiographic bone density values and measured biomechanical properties was observed. Therefore, bone mineral density of the third metacarpal bone determined by radiographic absorptiometry does not predict bone capacity to resist compression and flexion loads. Further studies should be developed to establish which techniques are reliably capable of giving such predictive information.

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