Transport viable heart tissue at physiological temperature yielded higher human cardiomyocytes compared to the conventional temperature

Author(s):  
Muhammad Arza Putra ◽  
Normalina Sandora ◽  
Suwarti ◽  
Retno Wahyu Nurhayati ◽  
Raisa Nauli ◽  
...  
2020 ◽  
Vol 41 (Supplement_2) ◽  
Author(s):  
D Bink ◽  
T.P Pham ◽  
P Hofmann ◽  
S Dimmeler ◽  
R.A Boon

Abstract   Ageing is the major risk factor for cardiovascular disease. Current therapies are mainly based on proteins, while targeting long non-coding RNAs (lncRNAs) is largely unexplored. Long non-coding RNAs are emerging as novel regulators of cellular functions and contributors to cardiovascular ageing. Although telomeres are heterochromatic regions, non-coding transcripts called Telomeric repeat-containing RNA (TERRA) are transcribed from the telomeres of most chromosomes. The transcription of TERRA starts at the subtelomere and ends in the telomere, leading to molecules of 0.2–10kb. This study aims to characterize the role of TERRA in the cardiovascular system. TERRA molecules from different chromosomes were upregulated in the hearts of old mice compared to young mice (p=0.002). An increased TERRA expression was also shown in heart tissue of patients with ischemic heart disease compared to donor heart tissue (p=0.001). In vitro an upregulation of the TERRA molecule transcribed from chromosome 20 (h20q-TERRA) was found in old passage human umbilical vein endothelial cells (HUVECs) (P15–17) compared to young HUVECs (P3) (p=0.014). IPSC-derived cardiomyocytes also increased the expression of h20q-TERRA with increasing passage (p=0.011). After knockdown of h20q-TERRA with LNA GapmeRs HUVECs show less sprout formation in a spheroid assay compared to negative control transfected HUVECs (p=0.002), without showing a change in migration (p=0.205) or proliferation (p=0.114). H20q-TERRA knockdown revealed that there was more apoptosis (p=0.015), more DNA damage as measured with the comet assay (p<0.001), increased γH2AX levels (p=0.029) and an increase in γH2AX colocalization with the telomere (p=0.011). The amount of phosphorylated P53 was also increased after knockdown (p=0.038), while it was decreased after TERRA overexpression (p=0.001). Inhibition of the ATM-yH2AX-P53 pathway did however not reduce the increased apoptosis after knockdown (KU60019 p=0.399; siP53 p=0.303). Silencing the m18-TERRA molecule in mouse endothelial H5V cells led to an increase in caspase activity (p=0.004) similar to what was shown in HUVECs. In addition, increased caspase activity (p=0.012), increased γH2AX levels (p<0.001) and increased γH2AX colocalization with the telomere (p=0.007) was also shown after silencing of h20q-TERRA in human cardiomyocytes. In summary, our data demonstrates that TERRA is upregulated with ageing and plays a role in endothelial and cardiomyocyte function and survival. These data show that TERRA transcripts are induced in cardiovascular ageing and are essential for endothelial cell function. Funding Acknowledgement Type of funding source: Public grant(s) – EU funding. Main funding source(s): Horizon 2020


2019 ◽  
Author(s):  
Hsiao-yun Y. Milliron ◽  
Matthew J. Weiland ◽  
Eric J. Kort ◽  
Stefan Jovinge

AbstractRationale-Adult human cardiomyocytes (CMs) do not complete cytokinesis despite passing through the S-phase of the cell cycle. As a result polyploidization and multinucleation occur. In order to get a deeper understanding of the mechanisms surrounding division of CMs there is a crucial need for a technique to isolate CMs that complete cell division/cytokinesis.Objective-Markers of cell cycle progression based on DNA content cannot distinguish between mitotic CMs that fail to complete cytokinesis from those cells that undergo true cell division. With the use of molecular beacons (MB) targeting specific mRNAs we aimed to identify truly proliferative CMs derived from hiPSCs.Methods and Results-Fluorescence activated cell-sorting combined with molecular beacons was performed to sort CM populations enriched for mitotic cells. Expressions of cell-cycle specific genes were confirmed by means of RT-qPCR, single-cell RNA sequencing (scRNA-seq). We further characterized the sorted groups by proliferation assays and time-lapse microscopy which confirmed the proliferative advantage of MB-positive cell populations relative to MB-negative and G2/M populations. Gene expression analysis revealed that the MB-positive CM subpopulation exhibited patterns consistent with the biological processes of nuclear division, chromosome segregation, and transition from M to G1 phase. The use of dual-MBs targeting CDC20 and SPG20 mRNAs (CDC20+SPG20+) enabled the enrichment of cytokinetic events. Interestingly, cells that did not complete cytokinesis and remained binucleated were found to be CDC20−SPG20+ while polyploid CMs that replicated DNA but failed to complete karyokinesis were found to be CDC20−SPG20−.Conclusions-This study demonstrates a novel alternative to existing DNA content-based approaches for sorting CMs with true mitotic potential that can be used to study in detail the unique dynamics of CM nuclei during mitosis. Together with high-throughput scRNA-seq, our technique for sorting live CMs undergoing cytokinesis would provide a basis for future studies to uncover mechanisms underlying the development and regeneration of heart tissue.


2020 ◽  
Vol 10 (4) ◽  
pp. 179 ◽  
Author(s):  
Vincenzo Quagliariello ◽  
Margherita Passariello ◽  
Domenica Rea ◽  
Antonio Barbieri ◽  
Martina Iovine ◽  
...  

Background: Several strategies based on immune checkpoint inhibitors (ICIs) have been developed for cancer therapy, opening to advantages in cancer outcomes. However, several ICI-induced side effects have emerged in these patients, especially a rare but clinically significant cardiotoxicity with high rate of mortality. We studied the cytotoxic and pro-inflammatory properties of Ipilimumab and Nivolumab, the underlying pathways and cytokine storm involved. Methods: Co-cultures of human cardiomyocytes and lymphocytes were exposed to Ipilimumab or Nivolumab; cell viability and expression of leukotrienes, NLRP3, MyD88, and p65/NF-kB were performed. C57 mice were treated with Ipilimumab (15 mg/kg); analysis of fractional shortening, ejection fraction, radial and longitudinal strain were made before and after treatments through 2D-echocardiography. Expression of NLRP3, MyD88, p65/NF-kB, and 12 cytokines were analyzed in murine myocardium. Results: Nivolumab and Ipilimumab exert effective anticancer, but also significant cardiotoxic effects in co-cultures of lymphocytes and tumor or cardiac cells. Both ICIs increased NLRP3, MyD88, and p65/NF-kB expression compared to untreated cells, however, the most pro-inflammatory and cardiotoxic effects were seen after exposure to Ipilimumab. Mice treated with Ipilimumab showed a significant decrease in fractional shortening and radial strain with respect to untreated mice, coupled with a significant increase in myocardial expression of NLRP3, MyD88, and several interleukins. Conclusions: Nivolumab and Ipilimumab exert cytotoxic effects mediated by the NLRP3/IL-1β and MyD88 pathways, leading to pro-inflammatory cytokine storm in heart tissue.


2017 ◽  
Vol 121 (suppl_1) ◽  
Author(s):  
Amaresh Ranjan ◽  
Sangeetha Vadakke Madathil ◽  
Hina Chaudhry

The adult mammalian heart is known to have a very low abundance of progenitor cells which can take part in active cycling and regeneration after damage. Cardiomyocytes exit the cell cycle soon after birth coincident with the silencing of cyclin A2 (CCNA2). In our previous studies, we demonstrated that viral delivery of Ccna2 induces cardiac regeneration in infarcted hearts of small and large animal models. However, the molecular mechanism whereby Ccna2 induces cardiac regeneration and increase in cardiac function deserves further study. To explore further, we isolated adult mouse cardiomyocytes and induced Ccna2 expression by using adenovirus transfection and cultured them for 3 weeks. Co-expression of the mature cardiac marker troponin Tc with the immature cardiac marker non-muscle myosin IIB was observed. Additionally, expression of epithelial to mesenchymal transition markers (vimentin and FSP1) was observed. Also, decreased expression of mature cardiac markers α-MHC , ckmt2 and cTnT was noted. To study the factors responsible for human cardiomyocyte plasticity and cell division, we have optimized a novel method for culturing adult human cardiomyocytes in our laboratory. We cultured cardiomyocytes isolated from heart tissue obtained from a 55 yr old male patient. After transfection with CCNA2 adenovirus made for human use (cTnT promoter driving human CCNA2 cDNA), they were co-transfected with two more adenoviruses (1) cTnT-GFP to label cardiomyocytes (green) and (2) CMV-α-actinin-m-Cherry to label the sarcomere (red). Time lapse live epifluorescence microscopy was carried out for 70 hrs and time lapse movies were prepared (please refer the youtube link to see a representative time lapse movie https://youtu.be/OBrJGCq7YCA ). Movies were analyzed to calculate the cytokinesis index in samples transfected with (Test) and without (Null) CCNA2 adenoviruses. We observed a significantly higher cytokinesis index in CCNA2 samples versus Null. We are further investigating the role of cyclin A2 in dedifferentiation of adult human cardiomyocytes to generate immature or progenitor cardiac cells and their contractile status, which could be utilized for regeneration and functional restoration of damaged adult heart tissue.


2019 ◽  
Author(s):  
Christopher Ashwood ◽  
Matthew Waas ◽  
Ranjuna Weerasekera ◽  
Rebekah L. Gundry

AbstractCell surface glycoproteins play critical roles in maintaining cardiac structure and function in health and disease and the glycan-moiety attached to the protein is critical for proper protein folding, stability and signaling. However, despite mounting evidence that glycan structures are key modulators of heart function and must be considered when developing cardiac biomarkers, we currently do not have a comprehensive view of the glycans present in the normal human heart. In the current study, we used porous graphitized carbon liquid chromatography interfaced with mass spectrometry (PGC-LC-MS) to generate glycan structure libraries for primary human heart tissue homogenate, cardiomyocytes (CM) enriched from human heart tissue, and human induced pluripotent stem cell derived CM (hiPSC-CM). Altogether, we established the first reference structure libraries of the cardiac glycome containing 265 N- and O-glycans. Comparing the N-glycome of CM enriched from primary heart tissue to that of heart tissue homogenate, 21 structures significantly differed, and the high mannose class is increased in enriched CM. Moreover, by comparing primary CM to hiPSC-CM collected during 20-100 days of differentiation, dynamic changes in the glycan profile throughout in vitro differentiation were observed and differences between primary and hiPSC-CM were revealed. Namely, >30% of the N-glycome significantly changed across these time-points of differentiation and only 23% of the N-glycan structures were shared between hiPSC-CM and primary CM. These observations are an important complement to current genomic, transcriptomic, and proteomic profiling and reveal new considerations for the use and interpretation of hiPSC-CM models for studies of human development, disease, and drug testing. Finally, these data are expected to support future regenerative medicine efforts by informing targets for evaluating the immunogenic potential of hiPSC-CM and harnessing differences between immature, proliferative hiPSC-CM and adult primary CM.


2013 ◽  
Vol 61 (S 01) ◽  
Author(s):  
L Conradi ◽  
S Schmidt ◽  
L Peters ◽  
A Eder ◽  
A Hansen ◽  
...  

The strategy of heart tissue engineering is simple enough: first remove all the cells from a organ then take the protein scaffold left behind and repopulate it with stem cells immunologically matched to the patient in need. While various suc- cessful methods for decellularization have been developed, and the feasibility of using decellularized whole hearts and extracellular matrix to support cells has been demonstrated, the reality of creating whole hearts for transplantation and of clinical application of decellularized extracellular matrix-based scaffolds will require much more research. For example, further investigations into how lineage-restricted progenitors repopulate the decellularized heart and differentiate in a site-specific manner into different populations of the native heart would be essential. The scaffold heart does not have to be human. Pig hearts carries all the essential components of the extracellular matrix. Through trial and error, scaling up the concentration, timing and pressure of the detergents, researchers have refined the decellularization process on hundreds of hearts and other organs, but this is only the first step. Further, the framework must be populated with human cells. Most researchers in the field use a mixture of two or more cell types, such as endothelial precursor cells to line blood vessels and muscle progenitors to seed the walls of the chambers. The final challenge is one of the hardest: vasculariza- tion, placing a engineered heart into a living animal, integration with the recipient tissue, and keeping it beating for a long time. Much remains to be done before a bioartificial heart is available for transplantation in humans.


2020 ◽  
Vol 10 (1) ◽  
Author(s):  
Pelin A. Golforoush ◽  
Priyanka Narasimhan ◽  
Patricia P. Chaves-Guerrero ◽  
Elsa Lawrence ◽  
Gary Newton ◽  
...  

2021 ◽  
Vol 14 (8) ◽  
pp. 748
Author(s):  
Péter P. Nánási ◽  
Balázs Horváth ◽  
Fábián Tar ◽  
János Almássy ◽  
Norbert Szentandrássy ◽  
...  

Due to the limited availability of healthy human ventricular tissues, the most suitable animal model has to be applied for electrophysiological and pharmacological studies. This can be best identified by studying the properties of ion currents shaping the action potential in the frequently used laboratory animals, such as dogs, rabbits, guinea pigs, or rats, and comparing them to those of human cardiomyocytes. The authors of this article with the experience of three decades of electrophysiological studies, performed in mammalian and human ventricular tissues and isolated cardiomyocytes, summarize their results obtained regarding the major canine and human cardiac ion currents. Accordingly, L-type Ca2+ current (ICa), late Na+ current (INa-late), rapid and slow components of the delayed rectifier K+ current (IKr and IKs, respectively), inward rectifier K+ current (IK1), transient outward K+ current (Ito1), and Na+/Ca2+ exchange current (INCX) were characterized and compared. Importantly, many of these measurements were performed using the action potential voltage clamp technique allowing for visualization of the actual current profiles flowing during the ventricular action potential. Densities and shapes of these ion currents, as well as the action potential configuration, were similar in human and canine ventricular cells, except for the density of IK1 and the recovery kinetics of Ito. IK1 displayed a largely four-fold larger density in canine than human myocytes, and Ito recovery from inactivation displayed a somewhat different time course in the two species. On the basis of these results, it is concluded that canine ventricular cells represent a reasonably good model for human myocytes for electrophysiological studies, however, it must be borne in mind that due to their stronger IK1, the repolarization reserve is more pronounced in canine cells, and moderate differences in the frequency-dependent repolarization patterns can also be anticipated.


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