scholarly journals Minimal in vivo requirements for developmentally regulated cardiac long intergenic non-coding RNAs

2019 ◽  
Author(s):  
Matthew R. George ◽  
Qiming Duan ◽  
Abigail Nagle ◽  
Irfan S. Kathiriya ◽  
Yu Huang ◽  
...  

AbstractLong intergenic non-coding RNAs (lincRNAs) have been implicated in aspects of gene regulation, but their requirement for development needs empirical interrogation. To begin to understand the roles lincRNAs might play in heart development, we computationally identified nine murine lincRNAs that have developmentally regulated transcriptional and epigenomic profiles specific to early heart differentiation. Six of the nine lincRNAs had in vivo expression patterns supporting a potential function in heart development, including a transcript downstream of the cardiac transcription factor Hand2 that we named Handlr (Hand2-associated lincRNA), Rubie, and Atcayos. We genetically ablated these six lincRNAs in mouse, which implicated genomic regulatory roles to four of the cohort, However, none of the lincRNA deletions led to severe cardiac phenotypes. Thus, we stressed the hearts of adult Handlr and Atcayos mutant mice by transverse aortic banding and found that absence of these lincRNAs did not affect cardiac hypertrophy or left ventricular function post-stress. Our results support roles for lincRNA transcripts and/or transcription to regulation of topologically associated genes. However, the individual importance of developmentally-specific lincRNAs is yet to be established. Their status as either gene-like entities or epigenetic components of the nucleus should be further considered.

1998 ◽  
Vol 4 (3) ◽  
pp. 6
Author(s):  
Helen Kiriazis ◽  
Vivek J. Kadambi ◽  
Damodhar P. Suresh ◽  
Robert G. Johnson ◽  
Evangelia G. Kranias ◽  
...  

2013 ◽  
Vol 113 (suppl_1) ◽  
Author(s):  
Ludovic O Bénard ◽  
Daniel S Matasic ◽  
Mathilde Keck ◽  
Anne-Marie Lompré ◽  
Roger J Hajjar ◽  
...  

STromal Interaction Molecule 1 (STIM1), a membrane protein of the sarcoplasmic reticulum, has recently been proposed as a positive regulator of cardiomyocyte growth by promoting Ca2+ entry through the plasma membrane and the activation of Ca2+-mediated signaling pathways. We demonstrated that STIM1 silencing prevented the development of left ventricular hypertrophy (LVH) in rats after abdominal aortic banding. Our aim was to study the role of STIM1 during the transition from LVH to heart failure (HF). For experimental timeline, see figure. Transverse Aortic Constriction (TAC) was performed in C57Bl/6 mice. In vivo gene silencing was performed using recombinant Associated AdenoVirus 9 (AAV9). Mice were injected with saline or with AAV9 expressing shRNA control or against STIM1 (shSTIM1) (dose: 1e+11 viral genome), which decreased STIM1 cardiac expression by 70% compared to control. While cardiac parameters were similar between the TAC groups at weeks 3 and 6, shSTIM1 animals displayed a progressive and total reversion of LVH with LV walls thickness returning to values observed in sham mice at week 8. This reversion was associated with the development of significant LV dilation and severe contractile dysfunction, as assessed by echography. Hemodynamic analysis confirmed the altered contractile function and dilation of shSTIM1 animals. Immunohistochemistry showed a trend to more fibrosis. Despite hypertrophic stimuli, there was a significant reduction in cardiac myocytes cross-section area in shSTIM1-treated animals as compared to other TAC mice. This study showed that STIM1 is essential to maintain compensatory LVH and that its silencing accelerates the transition to HF.


2002 ◽  
Vol 283 (2) ◽  
pp. H695-H706 ◽  
Author(s):  
Allison L. Bayer ◽  
Maria C. Heidkamp ◽  
Nehu Patel ◽  
Michael J. Porter ◽  
Steven J. Engman ◽  
...  

Proline-rich tyrosine kinase 2 (PYK2) is a member of the focal adhesion kinase (FAK) family of nonreceptor protein tyrosine kinases. PYK2 has been implicated in linking G protein-coupled receptors to activation of mitogen-activated protein kinase cascades and cellular growth in a variety of cell types. To determine whether PYK2 expression and phosphorylation is altered in left ventricular (LV) myocardium undergoing LV hypertrophy (LVH) and heart failure in vivo, suprarenal abdominal aortic coarctation was performed in 160-g male Sprague-Dawley rats. Immunohistochemistry and Western blotting were performed on LV tissue 1, 8, and 24 wk after aortic banding. Aortic banding produced sustained hypertension and gradually developing LVH. PYK2 levels were increased 1.8 ± 0.2-, 2.7 ± 0.6-, and 2.0 ± 0.2-fold in 1-, 8-, and 24-wk banded animals compared with their respective sham-operated controls. The increase in PYK2 expression was paralleled by an increase in PYK2 phosphorylation, both of which preceded the development of LVH. Immunohistochemistry revealed that enhanced PYK2 expression occurred predominantly in the cardiomyocyte population. Furthermore, there was a high degree of correlation ( R = 0.75; P< 0.001) between the level of PYK2 and the degree of LVH in 24-wk sham and banded animals. In contrast, FAK levels and FAK phosphorylation were not increased before the development of LVH. However, there was a high degree of correlation (R = 0.68; P < 0.001) between the level of FAK and the degree of LVH in 24-wk sham and banded rats. There was also a significant increase in the ratio of phosphospecific anti-FAK to FAK at this time point. These data are consistent with a role for PYK2 in the induction of pressure overload-induced cardiomyocyte hypertrophy, and suggest that PYK2 and FAK have distinctly different roles in LVH progression.


1997 ◽  
Vol 273 (3) ◽  
pp. H1368-H1376 ◽  
Author(s):  
N. Tanaka ◽  
L. Mao ◽  
F. A. DeLano ◽  
E. M. Sentianin ◽  
K. R. Chien ◽  
...  

This study describes miniaturized technology for the in vivo analysis of the volume and function of the embryonic mouse heart and the application of this technology to study the normal embryonic left ventricle (LV) at two stages of development. With the use of microsurgical techniques, embryos from embryonic day (ED) 10.5 (ED10.5) to ED16 were delivered individually from litters of normal dams, and cardiac visualization was achieved with the use of intravital microscopy by transillumination, with the umbilical circulation intact. At ED10.5-11, the heart could be imaged in color in the intact embryo, whereas at ED12.5 it was necessary to open the chest; at ED13.5-14.5, fluorescent imaging with the use of microinjection of fluorescein-conjugated albumin was necessary to visualize the LV chamber. At ED10.5-11, the LV end-diastolic volumes averaged 0.16 microliter (n = 14), and at ED13.5-14.5, they averaged 0.57 microliter (n = 16). At both ages there was a positive linear relationship between the LV end-diastolic volume and the stroke volume despite substantial variations in individual heart rates, reflecting the relative uniformity of the LV ejection fractions within each age group. The average of the individual ejection fractions was 27.4% at ED10.5-11 and 58.4% at ED13.5-14.5, the latter being within the normal range for the adult rodent heart. These methods will be useful for assessing in vivo cardiac function at ED10.5 and older murine embryos in litters of transgenic or gene-targeted mice when the mutation leads to later embryonic lethality.


2012 ◽  
Vol 111 (suppl_1) ◽  
Author(s):  
Namita M Varudkar ◽  
Jixiang Xia ◽  
Ibrahim Abukenda ◽  
Karl Pfeifer ◽  
Steven Ebert

Phenylethanolamine n-methyltransferase (Pnmt) catalyzes the conversion of norepinephrine to epinephrine, and thus serves as a marker for adrenergic cells. We employed a combination of immunofluorescent histochemical staining and genetic fate-mapping strategies to show that two separate Pnmt+ cell populations contribute to heart development. Intrinsic cardiac adrenergic (ICA) cells originate from the primary heart field, and contribute to pacemaking, conduction, and working (contractile) myocardium. A second population of cardiac Pnmt+ cells is derived from migrating neural crest. These neural crest adrenergic (NCA) cells appear to contribute to cardiac neurons. By adulthood, most of the Pnmt+ cells show a distinctively left-sided orientation in the heart, with nearly 90% of them being found in the left atrium and ventricle. Surprisingly large swaths of ventricular muscle are derived from Pnmt+ primer cells. Since this region of the heart is highly vulnerable to coronary artery disease and often sustains varying degrees of damage following myocardial infarction, we hypothesize that directed stem cell differentiation into Pnmt+ primer cells could serve as a valuable resource for repair and/or regeneration of left ventricular myocardium for heart disease patients. To test this hypothesis, we have generated stable recombinant mouse embryonic stem cell (mESC) lines that express various fluorescent marker proteins under the control of the endogenous Pnmt gene regulatory network. These cells can be rapidly expanded in culture, sorted, and used for transplantation studies in animal models to determine their therapeutic effectiveness. The cells can be induced along cardiogenic or neurogenic pathways in vitro, and the resulting Pnmt+ cells from each population can then be collected and tested in vivo. To achieve this goal, we have knocked-in a nuclear-localized enhanced green fluorescent protein into the Pnmt locus to create Pnmt-nEGFP recombinant mESCs and mice. We show that nEGFP expression is specifically expressed in Pnmt+ cells in vitro and in vivo. This strategy allows us to identify and isolate Pnmt+ cells to evaluate their effectiveness for cardiac regenerative medicine applications. .


2019 ◽  
Vol 20 (18) ◽  
pp. 4646 ◽  
Author(s):  
Keqin Li ◽  
Yuanliangzi Tian ◽  
Ya Yuan ◽  
Xiaolan Fan ◽  
Mingyao Yang ◽  
...  

Long non-coding RNAs (lncRNAs) are a class of non-coding RNAs longer than 200 nucleotides (nt). LncRNAs have high spatiotemporal specificity, and secondary structures have been preserved throughout evolution. They have been implicated in a range of biological processes and diseases and are emerging as key regulators of gene expression at the epigenetic, transcriptional, and post-transcriptional levels. Comparative analyses of lncRNA functions among multiple organisms have suggested that some of their mechanisms seem to be conserved. Transcriptome studies have found that some Drosophila lncRNAs have highly specific expression patterns in embryos, nerves, and gonads. In vivo studies of lncRNAs have revealed that dysregulated expression of lncRNAs in Drosophila may result in impaired embryo development, impaired neurological and gonadal functions, and poor stress resistance. In this review, we summarize the epigenetic, transcriptional, and post-transcriptional mechanisms of lncRNAs and mainly focus on recent insights into the transcriptome studies and biological functions of lncRNAs in Drosophila.


2002 ◽  
Vol 283 (6) ◽  
pp. H2371-H2378 ◽  
Author(s):  
Xue Zhao ◽  
Xiangru Lu ◽  
Qingping Feng

We recently demonstrated that mice deficient in endothelial nitric oxide (NO) synthase (eNOS) have congenital septal defects and postnatal heart failure. However, the mechanisms by which eNOS affects heart development are not clear. We hypothesized that deficiency in eNOS impairs myocardial angiogenesis. Myocardial capillary densities were measured morphometrically in neonatal mouse hearts. In vitro tube formation on Matrigel was investigated in cardiac endothelial cells. In vivo myocardial angiogenesis was performed by implanting Matrigel in the left ventricular myocardium. Myocardial capillary densities and VEGF mRNA expression were decreased in neonatal eNOS−/− compared with neonatal wild-type mice ( P < 0.01). Furthermore, in vitro tube formation from cardiac endothelial cells and in vivo myocardial angiogenesis were attenuated in eNOS−/− compared with wild-type mice ( P < 0.01). In vitro tube formation was inhibited by N G-nitro-l-arginine methyl ester in wild-type mice and restored by a NO donor, diethylenetriamine-NO, in eNOS−/− mice ( P < 0.05). In conclusion, deficiency in eNOS decreases VEGF expression and impairs myocardial angiogenesis and capillary development. Decreased myocardial angiogenesis may contribute to cardiac abnormalities during heart development in eNOS−/− mice.


Cells ◽  
2021 ◽  
Vol 10 (9) ◽  
pp. 2477
Author(s):  
Rui Machado ◽  
Agapios Sachinidis ◽  
Matthias E. Futschik

In vitro differentiation of embryonic stem cells (ESCs) provides a convenient basis for the study of microRNA-based gene regulation that is relevant for early cardiogenic processes. However, to which degree insights gained from in vitro differentiation models can be readily transferred to the in vivo system remains unclear. In this study, we profiled simultaneous genome-wide measurements of mRNAs and microRNAs (miRNAs) of differentiating murine ESCs (mESCs) and integrated putative miRNA-gene interactions to assess miRNA-driven gene regulation. To identify interactions conserved between in vivo and in vitro, we combined our analysis with a recent transcriptomic study of early murine heart development in vivo. We detected over 200 putative miRNA–mRNA interactions with conserved expression patterns that were indicative of gene regulation across the in vitro and in vivo studies. A substantial proportion of candidate interactions have been already linked to cardiogenesis, supporting the validity of our approach. Notably, we also detected miRNAs with expression patterns that closely resembled those of key developmental transcription factors. The approach taken in this study enabled the identification of miRNA interactions in in vitro models with potential relevance for early cardiogenic development. Such comparative approaches will be important for the faithful application of stem cells in cardiovascular research.


Circulation ◽  
2014 ◽  
Vol 130 (suppl_2) ◽  
Author(s):  
Melissa Swinnen ◽  
Hadewich Hermans ◽  
Mattia Quattrocelli ◽  
Peter Pokreisz ◽  
Hilde Gillijns ◽  
...  

Purpose: Left ventricular hypertrophy (LVH) is not just a compensatory response to increased biomechanical stress but is often associated with unfavorable outcome in patients. Mechanisms that govern transition from subclinical LVH to LV dysfunction are incompletely understood. Lately, single microRNAs (miRs), a class of small non-coding RNAs, have been implicated in LVH, but the expression dynamics and their role in transition to LV dysfunction remain unknown. Methods: We subjected mice to transverse aortic constriction (TAC) for 2, 4 and 10 weeks(wks) or to Ang-2 infusion for 4wks. Cardiac function was examined using serial echocardiography (TTE) and compared to sham mice (SH). MiR profiles in LV tissue were studied using the Nanostring platform, with significant differences between TAC or Ang2 vs SH set at a >2 up-or down-regulation with p<0.01. Western blotting and luciferase assay were performed for target confirmation. The impact of up-regulated miRs was validated in vivo by administration of specific AntagomiR vs Scrambled miRs (SCR) after TAC. Results-TTE showed a modest increase in LV end-systolic dimensions and a decline in fractional shortening (FS) after 4wks TAC and Ang2 . However, after 10wks TAC, LV dilation was present together with a reduction in FS (table1). Cardiac miR signatures indicated that 3 miRs were selectively up-regulated when transition to LV dysfunction was present at 10wks TAC. A common target gene for 2 of these up-regulated miRs (miR764-3p and miR-130b-3p) was confirmed. Moreover, in vivo antagomiR treatment for both miRs protected against cardiac dysfunction and fibrosis(table 1). Conclusion: miR analyses show important time- and stressor-dependent dynamic expression patterns during pressure overload. The miR signatures associated with transition from LVH to LV dysfunction and subsequent targeted antagomiR administration may hold promise for future therapy.


Circulation ◽  
2007 ◽  
Vol 116 (suppl_16) ◽  
Author(s):  
Ryotaro Yamada ◽  
Nozomi Watanabe ◽  
Teruyoshi Kume ◽  
Miwako Tsukiji ◽  
Kikuko Obase ◽  
...  

Background: Functional mitral regurgitation (MR) occurs as a consequence of regional or global left ventricular (LV) dysfunction despite a structurally normal mitral valve (MV). Degree of MV coaptation should be an important parameter in the assessment of functional MR. Purpose: We sought to investigate the change of MV coaptation and to clarify relationship between MV coaptation and development of MR in LV pressure overload. Methods: Using a canine model, LV pressure overload was induced by staged aortic banding (60 to 120mmHg). Echocardiographic examinations were performed before and during the banding. Degree of MR was evaluated by tracing the color jet MR area (MR area). By using a novel software system (RealView TM ) for 3D quantification, mitral annulus (MA) area, tenting volume, tenting length and 3D tenting surface area were analyzed. MA and surface of MV was manually traced both at the onset of MV closure [O] and at the maximum MV closure [M]. Coaptation index was calculated by the difference in 3D tenting surface area at O and at M devided by that at O. Results: MA area was gradually increased during banding ( p < 0.01). Tenting length and tenting volume tended to increase during banding but they did not reach statistical significance (tenting length; p = 0.17, tenting volume; p = 0.12). MR area increased with decrease in coaptation index (Figure ). The best cutoff value of the coaptation index to predict presence of MR was calculated as 0.24, giving a sensitivity of 82 % and specificity of 86 %. Conclusions: During aortic banding, MA dilated and coaptation of the MV decreased with apparent leaflet tenting. Coptation index might be able to predict the appearance of functional MR.


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