Dystrophin-deficient cardiomyopathy is becoming the dominant cause of death in patients with Duchenne muscular dystrophy (DMD), but its developmental process remains elusive.
Our results demonstrate that haploinsufficiency resulting from MYBPC3 complete deletion, potentially mediated by Alu recombination, is an important disease mechanism in cardiomyopathy and emphasizes the importance of copy number variation analysis in patients clinically suspected of HCM.
Heart failure invariably affects patients with various forms of Muscular Dystrophy (MD), but the onset and molecular sequelae of altered structure and function resulting from full-length dystrophin (Dp427) deficiency in MD heart tissue are poorly understood.To better understand the role of dystrophin in cardiomyocyte development and the earliest phase of DMD cardiomyopathy, we studied human cardiomyocytes differentiated from induced pluripotent stem cells (hiPSC-CMs) obtained from the urine of a Deuchenne Muscular Dystrophy (DMD) patient.
Improving skeletal muscle function without restoring dystrophin expression in cardiac tissue may exacerbate cardiomyopathy due to increased voluntary activity.
Phospholambanp.Arg14delcardiomyopathy is characterized by a distinct molecular signature compared to desmosomal ACM, specifically a different desmosomal protein distribution.
Together, our results reveal the significance of OFT expression of Tnnt2 for cardiac function and demonstrate zebrafish larva as a powerful and convenient <i>in vivo</i> platform for studying cardiomyopathy and the relevant therapeutic strategies.
Here, we present three cases carrying a loss-of-function (LoF) variant in a compound heterozygous state with a missense variant in either MYH7 or MYBPC3 leading to severe cardiomyopathy with left ventricular noncompaction.
With the generous support of the Leducq Foundation, our Transatlantic Network of Excellence consortium to cure Phospholamban (PLN)-induced cardiomyopathy (CURE-PLaN) unites 6 leading centers to address the current challenges associated with arrhythmogenic right ventricular cardiomyopathy/dilated cardiomyopathy (DCM) with an initial focus on PLN and development of effective treatments.
In the current preclinical study, we demonstrate the therapeutic potential of sarcospan (SSPN) overexpression to alleviate cardiomyopathy associated with Duchenne muscular dystrophy (DMD) utilizing dystrophin-deficient mdx mice with utrophin haploinsufficiency that more accurately represent the severe disease course of human DMD.
Previously, treatment with β-blockers showed beneficial effects on the development of cardiomyopathy in dystrophin-deficient (mdx) mice, but not in δ-sarcoglycan-deficient (Sgcd-/-) mice.
Although this minigene fully normalized skeletal muscle force, it only partially corrected electrocardiogram and heart hemodynamics in dystrophin-null mdx mice that had moderate cardiomyopathy.
Sarco(endo)plasmic reticulum Ca<sup>2+</sup> ATPase and its regulatory protein phospholamban (PLN) are potential therapeutic targets for DMD cardiomyopathy owing to their key role in regulating intracellular Ca<sup>2+</sup> cycling.
We collected mortality data from mutation-positive subjects with either DPP6-associated idiopathic ventricular fibrillation, SCN5A overlap syndrome, and PLN-R14del-mediated arrhythmogenic cardiomyopathy >2 to 10 years of ongoing clinical/cascade genetic screening.
We identified a novel dystrophin mutation (p.1667 del Ala), resulting in BMD-associated cardiomyopathy that demonstrated the pathological features of significant fibrofatty replacement in the sub-epicardial layer of the ventricle; further, the high-throughput sequencing is helpful for making an early diagnosis of BMD.
Compared with patients with variation in other sarcomeric genes, those with MYH7 variants were younger on first clinical encounter at the Sarcomeric Human Cardiomyopathy Registry site and more likely to be probands than the MYBPC3 variants.
In this genetic cardiomyopathy cohort, PLN Immunohistochemical analysis in LVAD biopsies was found to be a highly sensitive (100%) and specific (95%) method for demonstration of PLN protein aggregates in PLNp.Arg14delcardiomyopathy.
In conclusion, this study demonstrated that allogeneic WT-MPC-Exo transplantation transiently restored dystrophin gene expression and improved cardiac function in MDX mice, suggesting that allogenic exosomal delivery may serve as an alternative treatment for cardiomyopathy of DMD.
Four major procedures are discussed in this chapter: (1) preparation of hECTs from human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) on single-tissue and multitissue bioreactors; (2) data acquisition of hECT contractile function on both of these platforms; (3) hECT modeling of hereditary phospholamban-R14 deletion-dilated cardiomyopathy; and (4) cryo-injury and doxorubicin-induced hECT models of acquired cardiomyopathy.
We discovered that the hyperplastic to hypertrophic transition phase of mammalian heart development was altered in mice lacking MYBPC3 and this was the critical period for subsequent development of cardiomyopathy.