Your browser doesn't support javascript.
loading
Show: 20 | 50 | 100
Results 1 - 20 de 2.941
Filter
1.
J Gen Physiol ; 156(6)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38727632

ABSTRACT

JGP study (Duno-Miranda et al. https://doi.org/10.1085/jgp.202313522) shows that a mutation linked to dilated cardiomyopathy stabilizes ß-cardiac myosin in its autoinhibited, super-relaxed state.


Subject(s)
Mutation , Humans , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/metabolism , Animals
2.
Cells ; 13(9)2024 Apr 26.
Article in English | MEDLINE | ID: mdl-38727290

ABSTRACT

Dilated cardiomyopathy (DCM) is the most common cause of heart failure, with a complex aetiology involving multiple cell types. We aimed to detect cell-specific transcriptomic alterations in DCM through analysis that leveraged recent advancements in single-cell analytical tools. Single-cell RNA sequencing (scRNA-seq) data from human DCM cardiac tissue were subjected to an updated bioinformatic workflow in which unsupervised clustering was paired with reference label transfer to more comprehensively annotate the dataset. Differential gene expression was detected primarily in the cardiac fibroblast population. Bulk RNA sequencing was performed on an independent cohort of human cardiac tissue and compared with scRNA-seq gene alterations to generate a stratified list of higher-confidence, fibroblast-specific expression candidates for further validation. Concordant gene dysregulation was confirmed in TGFß-induced fibroblasts. Functional assessment of gene candidates showed that AEBP1 may play a significant role in fibroblast activation. This unbiased approach enabled improved resolution of cardiac cell-type-specific transcriptomic alterations in DCM.


Subject(s)
Cardiomyopathy, Dilated , Fibroblasts , Sequence Analysis, RNA , Single-Cell Analysis , Transcriptome , Humans , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/pathology , Cardiomyopathy, Dilated/metabolism , Fibroblasts/metabolism , Single-Cell Analysis/methods , Transcriptome/genetics , Sequence Analysis, RNA/methods , Myocardium/metabolism , Myocardium/pathology , Gene Expression Profiling
3.
Genome Biol ; 25(1): 135, 2024 May 23.
Article in English | MEDLINE | ID: mdl-38783323

ABSTRACT

BACKGROUND: Dilated cardiomyopathy (DCM) is one of the most common causes of heart failure. Multiple identified mutations in nexilin (NEXN) have been suggested to be linked with severe DCM. However, the exact association between multiple mutations of Nexn and DCM remains unclear. Moreover, it is critical for the development of precise and effective therapeutics in treatments of DCM. RESULTS: In our study, Nexn global knockout mice and mice carrying human equivalent G645del mutation are studied using functional gene rescue assays. AAV-mediated gene delivery is conducted through systemic intravenous injections at the neonatal stage. Heart tissues are analyzed by immunoblots, and functions are assessed by echocardiography. Here, we identify functional components of Nexilin and demonstrate that exogenous introduction could rescue the cardiac function and extend the lifespan of Nexn knockout mouse models. Similar therapeutic effects are also obtained in G645del mice, providing a promising intervention for future clinical therapeutics. CONCLUSIONS: In summary, we demonstrated that a single injection of AAV-Nexn was capable to restore the functions of cardiomyocytes and extended the lifespan of Nexn knockout and G645del mice. Our study represented a long-term gene replacement therapy for DCM that potentially covers all forms of loss-of-function mutations in NEXN.


Subject(s)
Cardiomyopathy, Dilated , Genetic Therapy , Mice, Knockout , Animals , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/therapy , Mice , Humans , Dependovirus/genetics , Myocytes, Cardiac/metabolism , Disease Models, Animal , Mutation , Genetic Vectors/administration & dosage , Gene Transfer Techniques
4.
Biomolecules ; 14(5)2024 Apr 27.
Article in English | MEDLINE | ID: mdl-38785931

ABSTRACT

Dilated cardiomyopathy (DCM) encompasses various acquired or genetic diseases sharing a common phenotype. The understanding of pathogenetic mechanisms and the determination of the functional effects of each etiology may allow for tailoring different therapeutic strategies. MicroRNAs (miRNAs) have emerged as key regulators in cardiovascular diseases, including DCM. However, their specific roles in different DCM etiologies remain elusive. Here, we applied mRNA-seq and miRNA-seq to identify the gene and miRNA signature from myocardial biopsies from four patients with DCM caused by volume overload (VCM) and four with ischemic DCM (ICM). Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analysis were used for differentially expressed genes (DEGs). The miRNA-mRNA interactions were identified by Pearson correlation analysis and miRNA target-prediction programs. mRNA-seq and miRNA-seq were validated by qRT-PCR and miRNA-mRNA interactions were validated by luciferase assays. We found 112 mRNAs and five miRNAs dysregulated in VCM vs. ICM. DEGs were positively enriched for pathways related to the extracellular matrix (ECM), mitochondrial respiration, cardiac muscle contraction, and fatty acid metabolism in VCM vs. ICM and negatively enriched for immune-response-related pathways, JAK-STAT, and NF-kappa B signaling. We identified four pairs of negatively correlated miRNA-mRNA: miR-218-5p-DDX6, miR-218-5p-TTC39C, miR-218-5p-SEMA4A, and miR-494-3p-SGMS2. Our study revealed novel miRNA-mRNA interaction networks and signaling pathways for VCM and ICM, providing novel insights into the development of these DCM etiologies.


Subject(s)
Cardiomyopathy, Dilated , MicroRNAs , RNA, Messenger , Humans , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/metabolism , Cardiomyopathy, Dilated/pathology , MicroRNAs/genetics , MicroRNAs/metabolism , RNA, Messenger/genetics , RNA, Messenger/metabolism , Gene Regulatory Networks , Male , Gene Expression Profiling , Gene Expression Regulation , Middle Aged , Female
5.
Channels (Austin) ; 18(1): 2355121, 2024 Dec.
Article in English | MEDLINE | ID: mdl-38762910

ABSTRACT

L-type calcium channels (LTCCs), the major portal for Ca2+ entry into cardiomyocytes, are essential for excitation-contraction coupling and thus play a central role in regulating overall cardiac function. LTCC function is finely tuned by multiple signaling pathways and accessory proteins. Leucine-rich repeat-containing protein 10 (LRRC10) is a little studied cardiomyocyte-specific protein recently identified as a modulator of LTCCs. LRRC10 exerts a remarkable effect on LTCC function, more than doubling L-type Ca2+ current (ICa,L) amplitude in a heterologous expression system by altering the gating of the channels without changing their surface membrane expression. Genetic ablation of LRRC10 expression in mouse and zebrafish hearts leads to a significant reduction in ICa,L density and a slowly progressive dilated cardiomyopathy in mice. Rare sequence variants of LRRC10 have been identified in dilated cardiomyopathy and sudden unexplained nocturnal cardiac death syndrome, but these variants have not been clearly linked to disease. Nevertheless, the DCM-associated variant, I195T, converted LRRC10 from a ICa,L potentiator to a ICa,L suppressor, thus illustrating the wide dynamic range of LRRC10-mediated ICa,L regulation. This review focuses on the contemporary knowledge of LTCC modulation by LRRC10 and discusses potential directions for future investigations.


Subject(s)
Calcium Channels, L-Type , Animals , Calcium Channels, L-Type/metabolism , Calcium Channels, L-Type/genetics , Humans , Myocytes, Cardiac/metabolism , Cardiomyopathy, Dilated/metabolism , Cardiomyopathy, Dilated/genetics , Membrane Proteins/metabolism , Membrane Proteins/genetics
6.
BMC Cardiovasc Disord ; 24(1): 282, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38811883

ABSTRACT

Sudden cardiac death (SCD) is a major public health issue worldwide. In the young (< 40 years of age), genetic cardiomyopathies and viral myocarditis, sometimes in combination, are the most frequent, but underestimated, causes of SCD. Molecular autopsy is essential for prevention. Several studies have shown an association between genetic cardiomyopathies and viral myocarditis, which is probably underestimated due to insufficient post-mortem investigations. We report on four autopsy cases illustrating the pathogenesis of these combined pathologies. In two cases, a genetic hypertrophic cardiomyopathy was diagnosed in combination with Herpes Virus Type 6 (HHV6) and/or Parvovirus-B19 (PVB19) in the heart. In the third case, autopsy revealed a dilated cardiomyopathy and virological analyses revealed acute myocarditis caused by three viruses: PVB19, HHV6 and Epstein-Barr virus. Genetic analyses revealed a mutation in the gene coding for desmin. The fourth case illustrated a channelopathy and a PVB19/HHV6 coinfection. Our four cases illustrate the highly probable deleterious role of cardiotropic viruses in the occurrence of SCD in subjects with genetic cardiomyopathies. We discuss the pathogenetic link between viral myocarditis and genetic cardiomyopathy. Molecular autopsy is essential in prevention of these SCD, and a close collaboration between cardiologists, pathologists, microbiologists and geneticians is mandatory.


Subject(s)
Autopsy , Death, Sudden, Cardiac , Herpesvirus 6, Human , Myocarditis , Parvovirus B19, Human , Humans , Myocarditis/virology , Myocarditis/pathology , Myocarditis/genetics , Death, Sudden, Cardiac/etiology , Death, Sudden, Cardiac/pathology , Death, Sudden, Cardiac/prevention & control , Male , Adult , Female , Herpesvirus 6, Human/genetics , Herpesvirus 6, Human/isolation & purification , Parvovirus B19, Human/genetics , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/virology , Cardiomyopathy, Dilated/pathology , Roseolovirus Infections/complications , Roseolovirus Infections/virology , Roseolovirus Infections/diagnosis , Roseolovirus Infections/pathology , Cardiomyopathy, Hypertrophic/genetics , Cardiomyopathy, Hypertrophic/pathology , Parvoviridae Infections/complications , Young Adult , Genetic Predisposition to Disease , Fatal Outcome , Epstein-Barr Virus Infections/complications , Herpesvirus 4, Human/genetics , Coinfection , Cause of Death , Mutation , Middle Aged
7.
J Gen Physiol ; 156(6)2024 Jun 03.
Article in English | MEDLINE | ID: mdl-38709176

ABSTRACT

Dilated cardiomyopathy (DCM) is a condition characterized by impaired cardiac function, due to myocardial hypo-contractility, and is associated with point mutations in ß-cardiac myosin, the molecular motor that powers cardiac contraction. Myocardial function can be modulated through sequestration of myosin motors into an auto-inhibited "super-relaxed" state (SRX), which may be further stabilized by a structural state known as the "interacting heads motif" (IHM). Here, we sought to determine whether hypo-contractility of DCM myocardium results from reduced function of individual myosin molecules or from decreased myosin availability to interact with actin due to increased IHM/SRX stabilization. We used an established DCM myosin mutation, E525K, and characterized the biochemical and mechanical activity of wild-type and mutant human ß-cardiac myosin constructs that differed in the length of their coiled-coil tail, which dictates their ability to form the IHM/SRX state. We found that short-tailed myosin constructs exhibited low IHM/SRX content, elevated actin-activated ATPase activity, and fast velocities in unloaded motility assays. Conversely, longer-tailed constructs exhibited higher IHM/SRX content and reduced actomyosin ATPase and velocity. Our modeling suggests that reduced velocities may be attributed to IHM/SRX-dependent sequestration of myosin heads. Interestingly, longer-tailed E525K mutants showed no apparent impact on velocity or actomyosin ATPase at low ionic strength but stabilized IHM/SRX state at higher ionic strength. Therefore, the hypo-contractility observed in DCM may be attributable to reduced myosin head availability caused by enhanced IHM/SRX stability in E525K mutants.


Subject(s)
Cardiac Myosins , Cardiomyopathy, Dilated , Ventricular Myosins , Animals , Humans , Actins/metabolism , Actins/genetics , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/metabolism , Cardiomyopathy, Dilated/physiopathology , Mutation , Myocardial Contraction/physiology , Ventricular Myosins/genetics , Ventricular Myosins/metabolism , Cardiac Myosins/genetics , Cardiac Myosins/metabolism
8.
Front Immunol ; 15: 1327372, 2024.
Article in English | MEDLINE | ID: mdl-38736889

ABSTRACT

Introduction: Growing evidence from animal models indicates that the myocardium hosts a population of B cells that play a role in the development of cardiomyopathy. However, there is minimal data on human myocardial B cells in the context of cardiomyopathy. Methods: We integrated single-cell and single-nuclei datasets from 45 healthy human hearts, 70 hearts with dilated cardiomyopathy (DCM), and 8 hearts with arrhythmogenic right ventricular cardiomyopathy (ARVC). Interactions between B cells and other cell types were investigated using the CellChat Package. Differential gene expression analysis comparing B cells across conditions was performed using DESeq2. Pathway analysis was performed using Ingenuity, KEGG, and GO pathways analysis. Results: We identified 1,100 B cells, including naive B cells and plasma cells. Cells showed an extensive network of interactions within the healthy myocardium that included outgoing signaling to macrophages, T cells, endothelial cells, and pericytes, and incoming signaling from endothelial cells, pericytes, and fibroblasts. This niche relied on ECM-receptor, contact, and paracrine interactions; and changed significantly in the context of cardiomyopathy, displaying disease-specific features. Differential gene expression analysis showed that in the context of DCM both naive and plasma B cells upregulated several pathways related to immune activation, including upregulation of oxidative phosphorylation, upregulation of leukocyte extravasation, and, in naive B cells, antigen presentation. Discussion: The human myocardium contains naive B cells and plasma cells, integrated into a diverse and dynamic niche that has distinctive features in healthy, DCM, and ARVC. Naive myocardial-associated B cells likely contribute to the pathogenesis of human DCM.


Subject(s)
Arrhythmogenic Right Ventricular Dysplasia , B-Lymphocytes , Cardiomyopathy, Dilated , Myocardium , Humans , Cardiomyopathy, Dilated/immunology , Cardiomyopathy, Dilated/genetics , Arrhythmogenic Right Ventricular Dysplasia/genetics , Arrhythmogenic Right Ventricular Dysplasia/metabolism , B-Lymphocytes/immunology , B-Lymphocytes/metabolism , Myocardium/metabolism , Myocardium/immunology , Myocardium/pathology , Male , Female , Cell Communication/immunology , Gene Expression Profiling , Middle Aged , Adult , Transcriptome , Gene Expression Regulation
9.
PLoS Genet ; 20(5): e1011279, 2024 May.
Article in English | MEDLINE | ID: mdl-38748723

ABSTRACT

The leiomodin (Lmod) family of actin-binding proteins play a critical role in muscle function, highlighted by the fact that mutations in all three family members (LMOD1-3) result in human myopathies. Mutations in the cardiac predominant isoform, LMOD2 lead to severe neonatal dilated cardiomyopathy. Most of the disease-causing mutations in the LMOD gene family are nonsense, or frameshift, mutations predicted to result in expression of truncated proteins. However, in nearly all cases of disease, little to no LMOD protein is expressed. We show here that nonsense-mediated mRNA decay, a cellular mechanism which eliminates mRNAs with premature termination codons, underlies loss of mutant protein from two independent LMOD2 disease-causing mutations. Furthermore, we generated steric-blocking oligonucleotides that obstruct deposition of the exon junction complex, preventing nonsense-mediated mRNA decay of mutant LMOD2 transcripts, thereby restoring mutant protein expression. Our investigation lays the initial groundwork for potential therapeutic intervention in LMOD-linked myopathies.


Subject(s)
Codon, Nonsense , Nonsense Mediated mRNA Decay , Humans , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/metabolism , Codon, Nonsense/genetics , Microfilament Proteins/genetics , Microfilament Proteins/metabolism , Muscle Proteins/genetics , Muscle Proteins/metabolism , Mutation , Nonsense Mediated mRNA Decay/genetics , RNA, Messenger/genetics , RNA, Messenger/metabolism
10.
Sci Rep ; 14(1): 11980, 2024 05 25.
Article in English | MEDLINE | ID: mdl-38796549

ABSTRACT

Pathogenic BAG5 variants recently linked to dilated cardiomyopathy (DCM) prompt further investigation into phenotypic, mutational, and pathomechanistic aspects. We explored the clinical and molecular characteristics of DCM associated with BAG5 variants, uncovering the consistently severe manifestations of the disease and its impact on the endoplasmic reticulum (ER) stress response. The analysis involved three siblings affected by DCM and arrhythmia, along with their four unaffected siblings, their unaffected father, and their mother who exhibited arrhythmia. The parents were consanguineous. Exome and Sanger sequencing identified a novel BAG5 variant, c.444_445delGA (p.Lys149AsnfsTer6), homozygous in affected siblings and heterozygous in parents and unaffected siblings. We generated heterozygous and homozygous Bag5 point mutant knock-in (KI) mice and evaluated cardiac pathophysiology under stress conditions, including tunicamycin (TN) administration. Bag5-/- mice displayed no abnormalities up to 12 months old and showed no anomalies during an exercise stress test. However, following TN injection, Bag5-/- mice exhibited significantly reduced left ventricular fractional shortening (LVFS) and ejection fraction (LVEF). Their cardiac tissues exhibited a notable increase in apoptotic cells, despite non-distinctive changes in CHOP and GRP78 levels. Interestingly, only Bag5 KI male mice demonstrated arrhythmia, which was more pronounced in Bag5-/- than in Bag5+/-males. Here, our study reveals a novel BAG5 mutation causing DCM by impairing the ER stress response, with observed sex-specific arrhythmia differences.


Subject(s)
Arrhythmias, Cardiac , Cardiomyopathy, Dilated , Endoplasmic Reticulum Chaperone BiP , Endoplasmic Reticulum Stress , Animals , Cardiomyopathy, Dilated/genetics , Endoplasmic Reticulum Stress/genetics , Humans , Arrhythmias, Cardiac/genetics , Male , Female , Mice , Pedigree , Mice, Knockout , Adult , Apoptosis/genetics , Mutation
11.
Int J Mol Sci ; 25(7)2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38612618

ABSTRACT

Dilated cardiomyopathy is a heterogeneous entity that leads to heart failure and malignant arrhythmias. Nearly 50% of cases are inherited; therefore, genetic analysis is crucial to unravel the cause and for the early identification of carriers at risk. A large number of variants remain classified as ambiguous, impeding an actionable clinical translation. Our goal was to perform a comprehensive update of variants previously classified with an ambiguous role, applying a new algorithm of already available tools. In a cohort of 65 cases diagnosed with dilated cardiomyopathy, a total of 125 genetic variants were classified as ambiguous. Our reanalysis resulted in the reclassification of 12% of variants from an unknown to likely benign or likely pathogenic role, due to improved population frequencies. For all the remaining ambiguous variants, we used our algorithm; 60.9% showed a potential but not confirmed deleterious role, and 24.5% showed a potential benign role. Periodically updating the population frequencies is a cheap and fast action, making it possible to clarify the role of ambiguous variants. Here, we perform a comprehensive reanalysis to help to clarify the role of most of ambiguous variants. Our specific algorithms facilitate genetic interpretation in dilated cardiomyopathy.


Subject(s)
Cardiomyopathy, Dilated , Heart Failure , Humans , Cardiomyopathy, Dilated/genetics , Algorithms , Gene Frequency
13.
BMC Pediatr ; 24(1): 226, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38561731

ABSTRACT

BACKGROUND: Dilated cardiomyopathy (DCM) commonly leads to heart failure (HF) and represents the most common indication for cardiac transplantation in the pediatric population. Clinical manifestations of DCM are mainly the symptoms of heart failure; it is diagnosed by EKG, chest x-ray and echocardiography. For the idiopathic and familial diseases cases of DCM, there are no definite guidelines for treatment in children as they are treated for prognostic improvement. CASE PRESENTATION: We report the case of a 2-year-old girl diagnosed with dilated cardiomyopathy associated with homozygous mutation in the Myosin Light Chain 3 gene admitted for edema in lower extremities, muscle weakness, lethargy and vomiting, and she was found to be in cardiogenic shock. Chest x-ray showed cardiomegaly and EKG showed first degree atrioventricular block. Echocardiogram showed severe biventricular systolic and diastolic dysfunction. After 70 days of hospitalization, the patient went into cardiac arrest with cessation of electrical and mechanical activity of the heart, despite cardiopulmonary resuscitative efforts. CONCLUSION: Although rare, pediatric DCM carries a high risk of morbidity and mortality and a lack of curative therapy.


Subject(s)
Cardiomyopathy, Dilated , Heart Failure , Heart Transplantation , Child, Preschool , Female , Humans , Cardiomyopathy, Dilated/genetics , Echocardiography , Heart Failure/genetics
14.
BMC Cardiovasc Disord ; 24(1): 224, 2024 Apr 25.
Article in English | MEDLINE | ID: mdl-38664609

ABSTRACT

BACKGROUND: Careful interpretation of the relation between phenotype changes of the heart and gene variants detected in dilated cardiomyopathy (DCM) is important for patient care and monitoring. OBJECTIVE: We sought to assess the association between cardiac-related genes and whole-heart myocardial mechanics or morphometrics in nonischemic dilated cardiomyopathy (NIDCM). METHODS: It was a prospective study consisting of patients with NIDCM. All patients were referred for genetic testing and a genetic analysis was performed using Illumina NextSeq 550 and a commercial gene capture panel of 233 genes (Systems Genomics, Cardiac-GeneSGKit®). It was analyzed whether there are significant differences in clinical, two-dimensional (2D) echocardiographic, and magnetic resonance imaging (MRI) parameters between patients with the genes variants and those without. 2D echocardiography and MRI were used to analyze myocardial mechanics and morphometrics. RESULTS: The study group consisted of 95 patients with NIDCM and the average age was 49.7 ± 10.5. All echocardiographic and MRI parameters of myocardial mechanics (left ventricular ejection fraction 28.4 ± 8.7 and 30.7 ± 11.2, respectively) were reduced and all values of cardiac chambers were increased (left ventricular end-diastolic diameter 64.5 ± 5.9 mm and 69.5 ± 10.7 mm, respectively) in this group. It was noticed that most cases of whole-heart myocardial mechanics and morphometrics differences between patients with and without gene variants were in the genes GATAD1, LOX, RASA1, KRAS, and KRIT1. These genes have not been previously linked to DCM. It has emerged that KRAS and KRIT1 genes were associated with worse whole-heart mechanics and enlargement of all heart chambers. GATAD1, LOX, and RASA1 genes variants showed an association with better cardiac function and morphometrics parameters. It might be that these variants alone do not influence disease development enough to be selective in human evolution. CONCLUSIONS: Combined variants in previously unreported genes related to DCM might play a significant role in affecting clinical, morphometrics, or myocardial mechanics parameters.


Subject(s)
Cardiomyopathy, Dilated , Genetic Predisposition to Disease , Phenotype , Ventricular Function, Left , Humans , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/physiopathology , Cardiomyopathy, Dilated/diagnostic imaging , Middle Aged , Male , Female , Adult , Prospective Studies , Ventricular Function, Left/genetics , Stroke Volume , Ventricular Remodeling/genetics , Magnetic Resonance Imaging , Biomechanical Phenomena , Genetic Variation , Echocardiography , Myocardial Contraction/genetics , Genetic Association Studies , Predictive Value of Tests
15.
J Am Coll Cardiol ; 83(17): 1640-1651, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38658103

ABSTRACT

BACKGROUND: Disease penetrance in genotype-positive (G+) relatives of families with dilated cardiomyopathy (DCM) and the characteristics associated with DCM onset in these individuals are unknown. OBJECTIVES: This study sought to determine the penetrance of new DCM diagnosis in G+ relatives and to identify factors associated with DCM development. METHODS: The authors evaluated 779 G+ patients (age 35.8 ± 17.3 years; 459 [59%] females; 367 [47%] with variants in TTN) without DCM followed at 25 Spanish centers. RESULTS: After a median follow-up of 37.1 months (Q1-Q3: 16.3-63.8 months), 85 individuals (10.9%) developed DCM (incidence rate of 2.9 per 100 person-years; 95% CI: 2.3-3.5 per 100 person-years). DCM penetrance and age at DCM onset was different according to underlying gene group (log-rank P = 0.015 and P <0.01, respectively). In a multivariable model excluding CMR parameters, independent predictors of DCM development were: older age (HR per 1-year increase: 1.02; 95% CI: 1.0-1.04), an abnormal electrocardiogram (HR: 2.13; 95% CI: 1.38-3.29); presence of variants in motor sarcomeric genes (HR: 1.92; 95% CI: 1.05-3.50); lower left ventricular ejection fraction (HR per 1% increase: 0.86; 95% CI: 0.82-0.90) and larger left ventricular end-diastolic diameter (HR per 1-mm increase: 1.10; 95% CI: 1.06-1.13). Multivariable analysis in individuals with cardiac magnetic resonance and late gadolinium enhancement assessment (n = 360, 45%) identified late gadolinium enhancement as an additional independent predictor of DCM development (HR: 2.52; 95% CI: 1.43-4.45). CONCLUSIONS: Following a first negative screening, approximately 11% of G+ relatives developed DCM during a median follow-up of 3 years. Older age, an abnormal electrocardiogram, lower left ventricular ejection fraction, increased left ventricular end-diastolic diameter, motor sarcomeric genetic variants, and late gadolinium enhancement are associated with a higher risk of developing DCM.


Subject(s)
Cardiomyopathy, Dilated , Genotype , Penetrance , Adult , Female , Humans , Male , Middle Aged , Young Adult , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/physiopathology , Connectin/genetics , Electrocardiography , Follow-Up Studies , Spain/epidemiology , Retrospective Studies
16.
Stem Cell Res ; 77: 103409, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38583294

ABSTRACT

Filamin C (FLNC) is a highly important actin crosslinker and multi-adaptor protein in striated skeletal and cardiac muscle. Mutations have been linked to a range of cardiomyopathy types. Here, we generated induced pluripotent stem cells (iPSC) from a patient with dilated cardiomyopathy (DCM) harboring a new, unique heterozygous FLNC mutation p.R2187P. From this patient-specific iPSC line, a corresponding isogenic control line was created by CRISPR/Cas9 genome editing. Both, the patient-specific and isogenic-control iPSC maintained full pluripotency, genomic integrity, and in vitro differentiation capacity. All iPSC lines differentiate into iPSC-cardiomyocytes, hence providing the possibility to study the pathogenesis of FLNC-mediated DCM further.


Subject(s)
CRISPR-Cas Systems , Cardiomyopathy, Dilated , Filamins , Induced Pluripotent Stem Cells , Humans , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/pathology , CRISPR-Cas Systems/genetics , Induced Pluripotent Stem Cells/metabolism , Filamins/genetics , Filamins/metabolism , Mutation , Cell Differentiation , Cell Line , Male
18.
J Biol Chem ; 300(5): 107255, 2024 May.
Article in English | MEDLINE | ID: mdl-38579991

ABSTRACT

Myocardial failure is associated with adverse remodeling, including loss of cardiomyocytes, hypertrophy, and alterations in cell-cell contacts. Striatin-interacting phosphatase and kinase (STRIPAK) complexes and their mammalian STE20-like kinase 4 (Mst4) have been linked to development of different diseases. The role and targets of Mst4 in cardiomyocytes have not been investigated yet. Multitissue immunoblot experiments show highly enriched Mst4 expression in rodent hearts. Analyses of human biopsy samples from patients suffering from dilated cardiomyopathy revealed that Mst4 is upregulated (5- to 8-fold p < 0.001) compared with nonfailing controls. Increased abundance of Mst4 could also be detected in mouse models of cardiomyopathy. We confirmed that Mst4 interacts with STRIPAK components in neonatal rat ventricular cardiomyocytes, indicating that STRIPAK is present in the heart. Immunofluorescence stainings and molecular interaction studies revealed that Mst4 is localized to the intercalated disc and interacts with several intercalated disc proteins. Overexpression of Mst4 in cardiomyocytes results in hypertrophy compared with controls. In adult rat cardiomyocytes, Mst4 overexpression increases cellular and sarcomeric fractional shortening (p < 0.05), indicating enhanced contractility. Overexpression of Mst4 also inhibits apoptosis shown by reduction of cleaved caspase3 (-69%, p < 0.0001), caspase7 (-80%, p < 0.0001), and cleaved Parp1 (-27%, p < 0.001). To elucidate potential Mst4 targets, we performed phosphoproteomics analyses in neonatal rat cardiomyocytes after Mst4 overexpression and inhibition. The results revealed target candidates of Mst4 at the intercalated disc. We identified Mst4 as a novel cardiac kinase that is upregulated in cardiomyopathy-regulating cardiomyocyte growth and survival.


Subject(s)
Myocytes, Cardiac , Protein Serine-Threonine Kinases , Up-Regulation , Humans , Myocytes, Cardiac/metabolism , Myocytes, Cardiac/pathology , Animals , Protein Serine-Threonine Kinases/metabolism , Protein Serine-Threonine Kinases/genetics , Rats , Mice , Cell Survival , Male , Cardiomyopathy, Dilated/metabolism , Cardiomyopathy, Dilated/pathology , Cardiomyopathy, Dilated/genetics , Cardiomyopathies/metabolism , Cardiomyopathies/pathology , Cardiomyopathies/genetics , Muscle Proteins/metabolism , Muscle Proteins/genetics , Cell Proliferation , Apoptosis , Intracellular Signaling Peptides and Proteins
19.
Neuromuscul Disord ; 37: 1-5, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38430701

ABSTRACT

This report describes a novel TTN -related phenotype in two brothers, both affected by a childhood onset, very slowly progressive myopathy with cores, associated with dilated cardiomyopathy only in their late disease stages. Clinical exome sequencing documented in both siblings the heterozygous c.2089A>T and c.19426+2T>A variants in TTN. The c.2089A>T, classified in ClinVar as possibly pathogenic, introduces a premature stop codon in exon 14, whereas the c.19426+2T>A affects TTN alternative splicing. The unfeasibility of segregation studies prevented us from establishing the inheritance mode of the muscle disease in this family, although the lack of any reported muscle or heart symptoms in both parents might support an autosomal recessive transmission. In this view, the occurrence of cardiomyopathy in both probands might be related to the c.2089A>T truncating variant in exon 14, and the childhood onset, slowly progressive myopathy to the c.19426+2T>A splicing variant, possibly allowing translation of an almost full length TTN protein.


Subject(s)
Cardiomyopathy, Dilated , Muscular Diseases , Male , Humans , Child , Connectin/genetics , Muscular Diseases/genetics , Phenotype , Cardiomyopathy, Dilated/genetics , Cardiomyopathy, Dilated/pathology , Codon, Nonsense , Mutation
20.
Int Heart J ; 65(2): 254-262, 2024.
Article in English | MEDLINE | ID: mdl-38556335

ABSTRACT

To date, whether there is any causal relationship between dilated cardiomyopathy (DCM) and the changes in the levels/expression of immune cells/cytokines is still unclear. This study aimed to investigate the causal relationship between the levels of various types of immune cells/cytokines and DCM. Herein, two-sample Mendelian randomization (MR) (TSMR) using R software was conducted. Single nucleotide polymorphisms (SNPs) related to the levels of various types of immune cells/cytokines and DCM were screened based on the genome-wide association studies (GWAS) obtained from open-source databases. The TSMR was conducted using inverse variance weighted (IVW), method, MR-Egger regression, weighted median method, and simple estimator based on mode to explore the causal association between the levels of each immune cell/cytokine and DCM. Sensitivity analysis was conducted using MR-Egger regression and a leave-one-out sensitivity test. A total of 1816 SNPs related to host immune status and DCM were identified. The IVW results showed a relationship between DCM and the circulating levels of basophils/eosinophils, total eosinophils-basophils, lymphocytes, and C-reactive protein (CRP). Increased lymphocytes levels (odds ratio (OR) = 0.91, 95% confidence interval (CI): 0.84-0.97, P = 0.005) were seen as protective against DCM, whereas increased basophil (OR = 1.18, 95% CI: 1.04-1.33, P = 0.022), eosinophil (OR = 1.1, 95% CI: 1.03-1.17, P = 0.007), eosinophil-basophil (OR = 1.09, 95% CI: 1.02-1.17, P = 0.014), and CRP (OR = 1.1, 95% CI: 1.03-1.18, P = 0.013) levels were associated with an increased risk of DCM. These analyses revealed that there may be a relationship between immune cells/select cytokine status and the onset of DCM. Future studies are required to further validate these outcomes in animal models and clinical trials.


Subject(s)
Cardiomyopathy, Dilated , Animals , Cardiomyopathy, Dilated/genetics , Genome-Wide Association Study , C-Reactive Protein , Causality , Cytokines
SELECTION OF CITATIONS
SEARCH DETAIL
...