RESUMEN
BACKGROUND: NOTCH1 pathogenic variants are implicated in multiple types of congenital heart defects including hypoplastic left heart syndrome, where the left ventricle is underdeveloped. It is unknown how NOTCH1 regulates human cardiac cell lineage determination and cardiomyocyte proliferation. In addition, mechanisms by which NOTCH1 pathogenic variants lead to ventricular hypoplasia in hypoplastic left heart syndrome remain elusive. METHODS: CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)/Cas9 genome editing was utilized to delete NOTCH1 in human induced pluripotent stem cells. Cardiac differentiation was carried out by sequential modulation of WNT signaling, and NOTCH1 knockout and wild-type differentiating cells were collected at day 0, 2, 5, 10, 14, and 30 for single-cell RNA-seq. RESULTS: Human NOTCH1 knockout induced pluripotent stem cells are able to generate functional cardiomyocytes and endothelial cells, suggesting that NOTCH1 is not required for mesoderm differentiation and cardiovascular development in vitro. However, disruption of NOTCH1 blocks human ventricular-like cardiomyocyte differentiation but promotes atrial-like cardiomyocyte generation through shortening the action potential duration. NOTCH1 deficiency leads to defective proliferation of early human cardiomyocytes, and transcriptomic analysis indicates that pathways involved in cell cycle progression and mitosis are downregulated in NOTCH1 knockout cardiomyocytes. Single-cell transcriptomic analysis reveals abnormal cell lineage determination of cardiac mesoderm, which is manifested by the biased differentiation toward epicardial and second heart field progenitors at the expense of first heart field progenitors in NOTCH1 knockout cell populations. CONCLUSIONS: NOTCH1 is essential for human ventricular-like cardiomyocyte differentiation and proliferation through balancing cell fate determination of cardiac mesoderm and modulating cell cycle progression. Because first heart field progenitors primarily contribute to the left ventricle, we speculate that pathogenic NOTCH1 variants lead to biased differentiation of first heart field progenitors, blocked ventricular-like cardiomyocyte differentiation, and defective cardiomyocyte proliferation, which collaboratively contribute to left ventricular hypoplasia in hypoplastic left heart syndrome.
Asunto(s)
Síndrome del Corazón Izquierdo Hipoplásico , Células Madre Pluripotentes Inducidas , Humanos , Células Endoteliales/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Diferenciación Celular/fisiología , Miocitos Cardíacos/metabolismo , Receptor Notch1/genética , Receptor Notch1/metabolismoRESUMEN
Long QT syndrome (LQTS) is a detrimental arrhythmia syndrome mainly caused by dysregulated expression or aberrant function of ion channels. The major clinical symptoms of ventricular arrhythmia, palpitations and syncope vary among LQTS subtypes. Susceptibility to malignant arrhythmia is a result of delayed repolarisation of the cardiomyocyte action potential (AP). There are 17 distinct subtypes of LQTS linked to 15 autosomal dominant genes with monogenic mutations. However, due to the presence of modifier genes, the identical mutation may result in completely different clinical manifestations in different carriers. In this review, we describe the roles of various ion channels in orchestrating APs and discuss molecular aetiologies of various types of LQTS. We highlight the usage of patient-specific induced pluripotent stem cell (iPSC) models in characterising fundamental mechanisms associated with LQTS. To mitigate the outcomes of LQTS, treatment strategies are initially focused on small molecules targeting ion channel activities. Next-generation treatments will reap the benefits from development of LQTS patient-specific iPSC platform, which is bolstered by the state-of-the-art technologies including whole-genome sequencing, CRISPR genome editing and machine learning. Deep phenotyping and high-throughput drug testing using LQTS patient-specific cardiomyocytes herald the upcoming precision medicine in LQTS.
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Células Madre Pluripotentes Inducidas , Síndrome de QT Prolongado , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Células Madre Pluripotentes Inducidas/patología , Medicina de Precisión , Síndrome de QT Prolongado/genética , Síndrome de QT Prolongado/terapia , Síndrome de QT Prolongado/diagnóstico , Mutación , Canales Iónicos/genética , Canales Iónicos/metabolismoRESUMEN
Patient-derived pluripotent stem cells (PSCs) have greatly transformed the current understanding of human heart development and cardiovascular disease. Cardiomyocytes derived from personalized PSCs are powerful tools for modeling heart disease and performing patient-based cardiac toxicity testing. However, these PSC-derived cardiomyocytes (PSC-CMs) are a mixed population of atrial-, ventricular-, and pacemaker-like cells in the dish, hindering the future of precision cardiovascular medicine. Recent insights gleaned from the developing heart have paved new avenues to refine subtype-specific cardiomyocytes from patients with known pathogenic genetic variants and clinical phenotypes. Here, we discuss the recent progress on generating subtype-specific (atrial, ventricular, and nodal) cardiomyocytes from the perspective of embryonic heart development and how human pluripotent stem cells will expand our current knowledge on molecular mechanisms of cardiovascular disease and the future of precision medicine.
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Cardiopatías , Células Madre Pluripotentes Inducidas , Células Madre Pluripotentes , Diferenciación Celular/genética , Humanos , Miocitos Cardíacos , Medicina de PrecisiónRESUMEN
Patient-specific pluripotent stem cells (PSCs) can be generated via nuclear reprogramming by transcription factors (i.e., induced pluripotent stem cells, iPSCs) or by somatic cell nuclear transfer (SCNT). However, abnormalities and preclinical application of differentiated cells generated by different reprogramming mechanisms have yet to be evaluated. Here we investigated the molecular and functional features, and drug response of cardiomyocytes (PSC-CMs) and endothelial cells (PSC-ECs) derived from genetically relevant sets of human iPSCs, SCNT-derived embryonic stem cells (nt-ESCs), as well as in vitro fertilization embryo-derived ESCs (IVF-ESCs). We found that differentiated cells derived from isogenic iPSCs and nt-ESCs showed comparable lineage gene expression, cellular heterogeneity, physiological properties, and metabolic functions. Genome-wide transcriptome and DNA methylome analysis indicated that iPSC derivatives (iPSC-CMs and iPSC-ECs) were more similar to isogenic nt-ESC counterparts than those derived from IVF-ESCs. Although iPSCs and nt-ESCs shared the same nuclear DNA and yet carried different sources of mitochondrial DNA, CMs derived from iPSC and nt-ESCs could both recapitulate doxorubicin-induced cardiotoxicity and exhibited insignificant differences on reactive oxygen species generation in response to stress condition. We conclude that molecular and functional characteristics of differentiated cells from human PSCs are primarily attributed to the genetic compositions rather than the reprogramming mechanisms (SCNT vs. iPSCs). Therefore, human iPSCs can replace nt-ESCs as alternatives for generating patient-specific differentiated cells for disease modeling and preclinical drug testing.
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Diferenciación Celular , Metilación de ADN , Células Endoteliales/metabolismo , Regulación de la Expresión Génica , Células Madre Embrionarias Humanas/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Miocitos Cardíacos/metabolismo , Técnicas de Transferencia Nuclear , Células Endoteliales/citología , Estudio de Asociación del Genoma Completo , Células Madre Embrionarias Humanas/citología , Humanos , Células Madre Pluripotentes Inducidas/citología , Miocitos Cardíacos/citologíaRESUMEN
The ability to differentiate human pluripotent stem cells (hPSCs) into cardiomyocytes (CMs) makes them an attractive source for repairing injured myocardium, disease modeling, and drug testing. Although current differentiation protocols yield hPSC-CMs to >90% efficiency, hPSC-CMs exhibit immature characteristics. With the goal of overcoming this limitation, we tested the effects of varying passive stretch on engineered heart muscle (EHM) structural and functional maturation, guided by computational modeling. Human embryonic stem cells (hESCs, H7 line) or human induced pluripotent stem cells (IMR-90 line) were differentiated to hPSC-derived cardiomyocytes (hPSC-CMs) in vitro using a small molecule based protocol. hPSC-CMs were characterized by troponin+ flow cytometry as well as electrophysiological measurements. Afterwards, 1.2 × 106 hPSC-CMs were mixed with 0.4 × 106 human fibroblasts (IMR-90 line) (3:1 ratio) and type-I collagen. The blend was cast into custom-made 12-mm long polydimethylsiloxane reservoirs to vary nominal passive stretch of EHMs to 5, 7, or 9 mm. EHM characteristics were monitored for up to 50 days, with EHMs having a passive stretch of 7 mm giving the most consistent formation. Based on our initial macroscopic observations of EHM formation, we created a computational model that predicts the stress distribution throughout EHMs, which is a function of cellular composition, cellular ratio, and geometry. Based on this predictive modeling, we show cell alignment by immunohistochemistry and coordinated calcium waves by calcium imaging. Furthermore, coordinated calcium waves and mechanical contractions were apparent throughout entire EHMs. The stiffness and active forces of hPSC-derived EHMs are comparable with rat neonatal cardiomyocyte-derived EHMs. Three-dimensional EHMs display increased expression of mature cardiomyocyte genes including sarcomeric protein troponin-T, calcium and potassium ion channels, ß-adrenergic receptors, and t-tubule protein caveolin-3. Passive stretch affects the structural and functional maturation of EHMs. Based on our predictive computational modeling, we show how to optimize cell alignment and calcium dynamics within EHMs. These findings provide a basis for the rational design of EHMs, which enables future scale-up productions for clinical use in cardiovascular tissue engineering. Stem Cells 2018;36:265-277.
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Biología Computacional/métodos , Miocardio/citología , Línea Celular , Citometría de Flujo , Humanos , Miocardio/metabolismo , Miocitos Cardíacos/citología , Miocitos Cardíacos/metabolismo , Células Madre Pluripotentes/citología , Células Madre Pluripotentes/metabolismo , Ingeniería de Tejidos/métodosRESUMEN
RATIONALE: Recent advances have improved our ability to generate cardiomyocytes from human induced pluripotent stem cells (hiPSCs) and human embryonic stem cells (hESCs). However, our understanding of the transcriptional regulatory networks underlying early stages (ie, from mesoderm to cardiac mesoderm) of cardiomyocyte differentiation remains limited. OBJECTIVE: To characterize transcriptome and chromatin accessibility during early cardiomyocyte differentiation from hiPSCs and hESCs. METHODS AND RESULTS: We profiled the temporal changes in transcriptome and chromatin accessibility at genome-wide levels during cardiomyocyte differentiation derived from 2 hiPSC lines and 2 hESC lines at 4 stages: pluripotent stem cells, mesoderm, cardiac mesoderm, and differentiated cardiomyocytes. Overall, RNA sequencing analysis revealed that transcriptomes during early cardiomyocyte differentiation were highly concordant between hiPSCs and hESCs, and clustering of 4 cell lines within each time point demonstrated that changes in genome-wide chromatin accessibility were similar across hiPSC and hESC cell lines. Weighted gene co-expression network analysis (WGCNA) identified several modules that were strongly correlated with different stages of cardiomyocyte differentiation. Several novel genes were identified with high weighted connectivity within modules and exhibited coexpression patterns with other genes, including noncoding RNA LINC01124 and uncharacterized RNA AK127400 in the module related to the mesoderm stage; E-box-binding homeobox 1 (ZEB1) in the module correlated with postcardiac mesoderm. We further demonstrated that ZEB1 is required for early cardiomyocyte differentiation. In addition, based on integrative analysis of both WGCNA and transcription factor motif enrichment analysis, we determined numerous transcription factors likely to play important roles at different stages during cardiomyocyte differentiation, such as T and eomesodermin (EOMES; mesoderm), lymphoid enhancer-binding factor 1 (LEF1) and mesoderm posterior BHLH transcription factor 1 (MESP1; from mesoderm to cardiac mesoderm), meis homeobox 1 (MEIS1) and GATA-binding protein 4 (GATA4) (postcardiac mesoderm), JUN and FOS families, and MEIS2 (cardiomyocyte). CONCLUSIONS: Both hiPSCs and hESCs share similar transcriptional regulatory mechanisms underlying early cardiac differentiation, and our results have revealed transcriptional regulatory networks and new factors (eg, ZEB1) controlling early stages of cardiomyocyte differentiation.
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Diferenciación Celular/fisiología , Cromatina/fisiología , Células Madre Embrionarias Humanas/fisiología , Células Madre Pluripotentes Inducidas/fisiología , Miocitos Cardíacos/fisiología , Transcriptoma/fisiología , Perfilación de la Expresión Génica/métodos , Redes Reguladoras de Genes/fisiología , HumanosRESUMEN
RATIONALE: Regulatory DNA elements in the human genome play important roles in determining the transcriptional abundance and spatiotemporal gene expression during embryonic heart development and somatic cell reprogramming. It is not well known how chromatin marks in regulatory DNA elements are modulated to establish cell type-specific gene expression in the human heart. OBJECTIVE: We aimed to decipher the cell type-specific epigenetic signatures in regulatory DNA elements and how they modulate heart-specific gene expression. METHODS AND RESULTS: We profiled genome-wide transcriptional activity and a variety of epigenetic marks in the regulatory DNA elements using massive RNA-seq (n=12) and ChIP-seq (chromatin immunoprecipitation combined with high-throughput sequencing; n=84) in human endothelial cells (CD31+CD144+), cardiac progenitor cells (Sca-1+), fibroblasts (DDR2+), and their respective induced pluripotent stem cells. We uncovered 2 classes of regulatory DNA elements: class I was identified with ubiquitous enhancer (H3K4me1) and promoter (H3K4me3) marks in all cell types, whereas class II was enriched with H3K4me1 and H3K4me3 in a cell type-specific manner. Both class I and class II regulatory elements exhibited stimulatory roles in nearby gene expression in a given cell type. However, class I promoters displayed more dominant regulatory effects on transcriptional abundance regardless of distal enhancers. Transcription factor network analysis indicated that human induced pluripotent stem cells and somatic cells from the heart selected their preferential regulatory elements to maintain cell type-specific gene expression. In addition, we validated the function of these enhancer elements in transgenic mouse embryos and human cells and identified a few enhancers that could possibly regulate the cardiac-specific gene expression. CONCLUSIONS: Given that a large number of genetic variants associated with human diseases are located in regulatory DNA elements, our study provides valuable resources for deciphering the epigenetic modulation of regulatory DNA elements that fine-tune spatiotemporal gene expression in human cardiac development and diseases.
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Ensamble y Desensamble de Cromatina , Cromatina/genética , ADN/genética , Células Endoteliales/metabolismo , Epigénesis Genética , Fibroblastos/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Miocitos Cardíacos/metabolismo , Elementos Reguladores de la Transcripción , Animales , Células Cultivadas , Reprogramación Celular , Técnicas de Reprogramación Celular , Cromatina/metabolismo , ADN/metabolismo , Metilación de ADN , Regulación del Desarrollo de la Expresión Génica , Genotipo , Histonas/genética , Histonas/metabolismo , Humanos , Ratones Transgénicos , Fenotipo , Regiones Promotoras Genéticas , TransfecciónRESUMEN
Truncus arteriosus (TA) is a congenital heart defect where one main blood vessel emerges from the heart, instead of individual aorta and pulmonary artreries. Peripheral mononuclear cells (PBMCs) of a male infant with TA were reporogrammed using Sendai virus. The resultant iPSC line (NCHi015-A) displayed normal colony formation, expressed pluripotency markers, and differentiated into cells from three germ layers. NCHi015-A was matched to the patient's genetic profile, had normal karyotype, retained genetic variants in KMT2D and NOTCH1, and tested negative for reprogramming transgene. This iPSC line can be used for studying congenital heart defects associated with genetic variants in KMT2D and NOTCH1.
Asunto(s)
Células Madre Pluripotentes Inducidas , Receptor Notch1 , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Masculino , Receptor Notch1/genética , Receptor Notch1/metabolismo , Tronco Arterial , Proteínas de Unión al ADN/genética , Línea Celular , Heterocigoto , Diferenciación Celular , Proteínas de NeoplasiasRESUMEN
Pulmonary atresia with intact ventricular septum (PA/IVS) is a rare congenital heart defect that causes a significant decrease of blood outflow from the heart and is fatal if left untreated. iPSC line NCHi013-A was produced from peripheral blood mononuclear cells from a male child with PA/IVS using Sendai virus reprogramming. NCHi013-A displayed normal stem cell morphology, expressed markers for pluripotency, and presented ability to differentiate into cells of endoderm, ectoderm, and mesoderm lineages. The iPSC line also maintained normal karyotype, was validated for cell identity, and tested negative for transgenes and mycoplasma contamination.
Asunto(s)
Células Madre Pluripotentes Inducidas , Atresia Pulmonar , Masculino , Atresia Pulmonar/patología , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Preescolar , Diferenciación Celular , Cardiopatías Congénitas/patología , Línea CelularRESUMEN
Pulmonary atresia with intact ventricular septum (PA-IVS) is a rare congenital heart defect characterized by underdeveloped pulmonary valve and right ventricular hypoplasia. Neonates undergoing surgery to open pulmonary valve have a range of post-surgical ventricular recovery: single-ventricle (1v) palliation, one-and-half ventricle (1.5v) palliation, and bi-ventricular (2v) repair. PA-IVS-1.5v typically requires surgical intervention to install cavopulmonary shunt and entails partial right ventricle recovery. NCHi016-A is an iPSC line derived from a 5-year-old female with PA-IVS-1.5v using Sendai Virus reprogramming. This iPSC line shows typical iPSC morphology, has normal karyotype, expresses pluripotency markers, and has potential to differentiate into three germ layers.
Asunto(s)
Células Madre Pluripotentes Inducidas , Atresia Pulmonar , Femenino , Atresia Pulmonar/patología , Atresia Pulmonar/cirugía , Humanos , Células Madre Pluripotentes Inducidas/metabolismo , Preescolar , Línea Celular , Cardiopatías Congénitas/patología , Cardiopatías Congénitas/cirugía , Diferenciación Celular , Ventrículos Cardíacos/patologíaRESUMEN
During early mammalian embryogenesis, there is a wave of DNA demethylation postfertilization and de novo methylation around implantation. The paternal genome undergoes active DNA demethylation, whereas the maternal genome is passively demethylated after fertilization in most mammals except for sheep and rabbits. However, the emerging genome-wide DNA methylation landscape has revealed a regulatory and locus-specific DNA methylation reprogramming pattern in mammalian preimplantation embryos. Here we optimized a bisulfite sequencing protocol to draw base-resolution DNA methylation profiles of several selected genes in gametes, early embryos, and somatic tissue. We observed locus-specific DNA methylation reprogramming in early porcine embryos. First, some pluripotency genes (POU5F1 and NANOG) followed a typical wave of DNA demethylation and remethylation, whereas CpG-rich regions of SOX2 and CDX2 loci were hypomethylated throughout development. Second, a differentially methylated region of an imprint control region in the IGF2/H19 locus exhibited differential DNA methylation which was maintained in porcine early embryos. Third, a centromeric repeat element retained a moderate DNA methylation level in gametes, early embryos, and somatic tissue. The diverse DNA methylation reprogramming during early embryogenesis is thought to be possibly associated with the multiple functions of DNA methylation in transcriptional regulation, genome stability and genomic imprinting. The latest technology such as oxidative bisulfite sequencing to identify 5-hydroxymethylcytosine will further clarify the DNA methylation reprogramming during porcine embryonic development.
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Metilación de ADN/fisiología , ADN/metabolismo , Desarrollo Embrionario/fisiología , Sitios Genéticos/fisiología , Porcinos/embriología , Porcinos/genética , Animales , ADN/genética , Metilación de ADN/genética , Desarrollo Embrionario/genética , Femenino , Fertilización In Vitro , Sitios Genéticos/genética , Impresión Genómica , Proteínas de Homeodominio/genética , Proteínas de Homeodominio/metabolismo , Técnicas In Vitro , Factor II del Crecimiento Similar a la Insulina/genética , Factor II del Crecimiento Similar a la Insulina/metabolismo , Masculino , Factor 3 de Transcripción de Unión a Octámeros/genética , Factor 3 de Transcripción de Unión a Octámeros/metabolismo , Factores de Transcripción SOXB1/genética , Factores de Transcripción SOXB1/metabolismo , SulfitosRESUMEN
Hypoplastic left heart syndrome (HLHS) is a congenital heart malformation clinically characterized by an underdeveloped left ventricle, mitral or aortic valve stenosis or atresia, and narrowed ascending aorta. Although genetic etiology of HLHS is heterogenous, recurrent NOTCH1 variants have been associated with this defect. We report generation of an iPSC line derived from a female with HLHS with a heterozygous missense NOTCH1 (c.2058G > A; p.Gly661Ser) mutation within the conserved EGF-like repeat 17. This iPSC line exhibited typical cellular morphology, normal karyotype, high expression of pluripotent markers, and trilineage differentiation potential; and can be leveraged to dissect the complex NOTCH1-mediated HLHS disease mechanism.
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Cardiopatías Congénitas , Síndrome del Corazón Izquierdo Hipoplásico , Células Madre Pluripotentes Inducidas , Humanos , Femenino , Síndrome del Corazón Izquierdo Hipoplásico/genética , Síndrome del Corazón Izquierdo Hipoplásico/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Cardiopatías Congénitas/metabolismo , Mutación/genética , Heterocigoto , Receptor Notch1/genética , Receptor Notch1/metabolismoRESUMEN
Down syndrome is a genetic anomaly that manifests when there is a mistake during cell division, resulting in an additional chromosome 21. Down syndrome can impact cognitive capabilities and physical development, giving rise to diverse developmental disparities and an elevated likelihood of certain health issues. The iPSC line NCHi010-A was generated from peripheral blood mononuclear cells of a 6-year-old female with Down syndrome and without congenital heart disease using Sendai virus reprogramming. NCHi010-A displayed a morphology of pluripotent stem cells, expressed pluripotency markers, retained trisomy 21 karyotype, and demonstrated potential to differentiate into cells representative of the three germ layers.
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Síndrome de Down , Cardiopatías Congénitas , Células Madre Pluripotentes Inducidas , Femenino , Humanos , Niño , Células Madre Pluripotentes Inducidas/metabolismo , Reprogramación Celular , Síndrome de Down/metabolismo , Diferenciación Celular , Leucocitos Mononucleares/metabolismo , Línea Celular , Vectores Genéticos , Factores de Transcripción/genética , Cardiopatías Congénitas/genéticaRESUMEN
Down syndrome is a congenital disorder resulting from an extra full or partial chromosome 21, which is characterized by a spectrum of systemic developmental abnormalities, including those affecting the cardiovascular system. Here, we generated an iPSC line from peripheral blood mononuclear cells of a male adolescent with Down syndrome-associated congenital heart defects through Sendai virus-mediated transfection of 4 Yamanaka factors. This line exhibited normal morphology, expressed pluripotency markers, trisomy 21 karyotype, and could be differentiated into three germ layers. This iPSC line can be used for studying cellular and developmental etiologies of congenital heart defects induced by aneuploidy of chromosome 21.
Asunto(s)
Síndrome de Down , Cardiopatías Congénitas , Células Madre Pluripotentes Inducidas , Humanos , Masculino , Adolescente , Reprogramación Celular , Síndrome de Down/complicaciones , Leucocitos Mononucleares , Línea Celular , Vectores Genéticos , Factores de Transcripción/genética , Diferenciación Celular , Cardiopatías Congénitas/genéticaRESUMEN
Alagille syndrome (ALGS) is a multisystem disease with high variability in clinical features. ALGS is predominantly caused by pathogenic variants in the Notch ligand JAG1. An iPSC line, NCHi011-A, was generated from a ALGS patient with complex cardiac phenotypes consisting of pulmonic valve and branch pulmonary artery stenosis. NCHi011-A is heterozygous for a single base duplication causing a frameshift in the JAG1 gene. This iPSC line demonstrates normal cellular morphology, expression of pluripotency markers, trilineage differentiation potential, and identity to the source patient. NCHi011-A provides a resource for modeling ALGS and investigating the role of Notch signaling in the disease.
Asunto(s)
Síndrome de Alagille , Células Madre Pluripotentes Inducidas , Femenino , Humanos , Adulto Joven , Adulto , Síndrome de Alagille/genética , Síndrome de Alagille/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismo , Corazón , Diferenciación CelularRESUMEN
Alagille syndrome (ALGS) is an autosomal dominant disease affecting the liver, heart and other organs with high variability. About 95% of ALGS cases are associated with pathogenic variants in JAG1, encoding the Jagged1 ligand that binds to Notch receptors. The iPSC line NCHi012-A was derived from an ALGS patient with cholestatic liver disease and mild pulmonary stenosis, who is heterozygous for a 2â¯bp deletion in the JAG1 coding sequence. We report here an initial characterization of NCHi012-A to evaluate its morphology, pluripotency, differentiation potential, genotype, karyotype and identity to the source patient.
Asunto(s)
Síndrome de Alagille , Células Madre Pluripotentes Inducidas , Humanos , Síndrome de Alagille/genética , Síndrome de Alagille/metabolismo , Células Madre Pluripotentes Inducidas/metabolismo , Receptores Notch/metabolismo , Corazón , Proteína Jagged-1/genética , Proteína Jagged-1/metabolismoRESUMEN
The pleiotropic benefits of statins in cardiovascular diseases that are independent of their lipid-lowering effects have been well documented, but the underlying mechanisms remain elusive. Here we show that simvastatin significantly improves human induced pluripotent stem cell-derived endothelial cell functions in both baseline and diabetic conditions by reducing chromatin accessibility at transcriptional enhanced associate domain elements and ultimately at endothelial-to-mesenchymal transition (EndMT)-regulating genes in a yes-associated protein (YAP)-dependent manner. Inhibition of geranylgeranyltransferase (GGTase) I, a mevalonate pathway intermediate, repressed YAP nuclear translocation and YAP activity via RhoA signaling antagonism. We further identified a previously undescribed SOX9 enhancer downstream of statin-YAP signaling that promotes the EndMT process. Thus, inhibition of any component of the GGTase-RhoA-YAP-SRY box transcription factor 9 (SOX9) signaling axis was shown to rescue EndMT-associated endothelial dysfunction both in vitro and in vivo, especially under diabetic conditions. Overall, our study reveals an epigenetic modulatory role for simvastatin in repressing EndMT to confer protection against endothelial dysfunction.
RESUMEN
Congenital heart disease (CHD) represents a major class of birth defects worldwide and is associated with cardiac malformations that often require surgical intervention immediately after birth. Despite the intense efforts from multicentric genome/exome sequencing studies that have identified several genetic variants, the etiology of CHD remains diverse and often unknown. Genetically modified animal models with candidate gene deficiencies continue to provide novel molecular insights that are responsible for fetal cardiac development. However, the past decade has seen remarkable advances in the field of human induced pluripotent stem cell (hiPSC)-based disease modeling approaches to better understand the development of CHD and discover novel preventative therapies. The iPSCs are derived from reprogramming of differentiated somatic cells to an embryonic-like pluripotent state via overexpression of key transcription factors. In this review, we describe how differentiation of hiPSCs to specialized cardiac cellular identities facilitates our understanding of the development and pathogenesis of CHD subtypes. We summarize the molecular and functional characterization of hiPSC-derived differentiated cells in support of normal cardiogenesis, those that go awry in CHD and other heart diseases. We illustrate how stem cell-based disease modeling enables scientists to dissect the molecular mechanisms of cell-cell interactions underlying CHD. We highlight the current state of hiPSC-based studies that are in the verge of translating into clinical trials. We also address limitations including hiPSC-model reproducibility and scalability and differentiation methods leading to cellular heterogeneity. Last, we provide future perspective on exploiting the potential of hiPSC technology as a predictive model for patient-specific CHD, screening pharmaceuticals, and provide a source for cell-based personalized medicine. In combination with existing clinical and animal model studies, data obtained from hiPSCs will yield further understanding of oligogenic, gene-environment interaction, pathophysiology, and management for CHD and other genetic cardiac disorders.
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Cardiopatías Congénitas , Células Madre Pluripotentes Inducidas , Animales , Cardiopatías Congénitas/genética , Humanos , Células Madre Pluripotentes Inducidas/fisiología , Organogénesis , Preparaciones Farmacéuticas , Reproducibilidad de los Resultados , Factores de TranscripciónRESUMEN
The generation of cardiomyocytes (CMs) and endothelial cells (ECs) from human induced pluripotent stem cells (iPSCs) allows for precise modeling of cardiovascular disease using clinically relevant and patient-specific cells. Differentiation of human iPSCs into cardiomyocytes (iPSC-CMs) and endothelial cells (iPSC-ECs) is governed by small molecules that regulate the WNT signaling pathway. Here we outline the detailed steps to generate iPSC-CMs and iPSC-ECs through small molecule-mediated monolayer differentiation.