Aims: Mutations in the Lamin A/C gene may cause atrioventricular block, supraventricular arrhythmias, ventricular arrhythmias (VA), and dilated cardiomyopathy. We aimed to explore the predictors and the mechanisms of VA in Lamin A/C mutation-positive subjects.
Methods And Results: We included 41 Lamin A/C mutation-positive subjects. PR-interval and occurrence of VA were recorded. Left ventricular (LV) myocardial function was assessed as ejection fraction and speckle tracking longitudinal strain by echocardiography. Magnetic resonance imaging was performed to assess fibrosis in a selection of subjects. Ventricular arrhythmias were documented in 21 patients (51%). Prolonged PR-interval was the best predictor of VA (P < 0.001). Myocardial function by strain was reduced in the interventricular septum compared with the rest of the LV segments (-16.7% vs. -18.7%, P = 0.001) and correlated to PR-interval (R = 0.41, P = 0.03). Myocardial fibrosis was found exclusively in the interventricular septum and only in patients with VA (P = 0.007). PR-interval was longer in patients with septal fibrosis compared with those without (320 ± 66 vs. 177 ± 40 ms, P < 0.001).
Conclusion: Prolonged PR-interval was the best predictor of VA in Lamin A/C mutation-positive subjects. Electrical, mechanical, and structural cardiac properties were related in these subjects. Myocardial function was most reduced in the interventricular septum and correlated to prolonged PR-interval. Myocardial septal fibrosis was associated with prolonged PR-interval and VA. Localized fibrosis in the interventricular septum may be the mechanism behind reduced septal function, atrioventricular block and VA in Lamin A/C mutation-positive subjects.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1093/europace/eut291 | DOI Listing |
Soft Matter
January 2025
Laboratoire de Physique de l'École normale supérieure, ENS, Université PSL, CNRS, Sorbonne Université, Université Paris Cité, F-75005 Paris, France.
Physical models of cell motility rely mostly on cytoskeletal dynamical assembly. However, when cells move through the complex 3D environment of living tissues, they have to squeeze their nucleus that is stiffer than the rest of the cell. The lamin network, organised as a shell right underneath the nuclear membrane, contributes to the nuclear integrity and stiffness.
View Article and Find Full Text PDFNucleus
December 2025
Center for Translational Medicine, Department of Medicine, Thomas Jefferson University, Philadelphia, PA, USA.
Over the past 25 years, nuclear envelope (NE) perturbations have been reported in various experimental models with mutations in the gene. Although the hypothesis that NE perturbations from mutations are a fundamental feature of striated muscle damage has garnered wide acceptance, the molecular sequalae provoked by the NE damage and how they underlie disease pathogenesis such as cardiomyopathy ( cardiomyopathy) remain poorly understood. We recently shed light on one such consequence, by employing a cardiomyocyte-specific deletion in the adult heart.
View Article and Find Full Text PDFInt J Biol Sci
January 2025
School of Medicine, Nankai University, Tianjin, China.
Bladder cancer (BC) is a prevalent urinary malignancy and muscle-invasive bladder cancer (MIBC) is particularly aggressive and associated with poor prognosis. One of MIBC features is the nuclear atypia. However, the molecular mechanism underlying MIBC remains unclear.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
Hutchinson-Gilford progeria syndrome (HGPS) is a pediatric condition characterized by clinical features that resemble accelerated aging. The abnormal accumulation of a toxic form of the lamin A protein known as progerin disrupts cellular functions, leading to various complications, including growth retardation, loss of subcutaneous fat, abnormal skin, alopecia, osteoporosis, and progressive joint contractures. Death primarily occurs as the result of complications from progressive atherosclerosis, especially from cardiac disease, such as myocardial infarction or heart failure, or cerebrovascular disease like stroke.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Bone Pathophysiology Research Unit, Bambino Gesù Children's Hospital, IRCCS, 00146 Rome, Italy.
Laminopathies represent a wide range of genetic disorders caused by mutations in gene-encoding proteins of the nuclear lamina. Altered nuclear mechanics have been associated with laminopathies, given the key role of nuclear lamins as mechanosensitive proteins involved in the mechanotransduction process. To shed light on the nuclear partners cooperating with altered lamins, we focused on Src tyrosine kinase, known to phosphorylate proteins of the nuclear lamina.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!