The Cardiomyopathy Lamin A/C D192G Mutation Disrupts Whole-Cell Biomechanics in Cardiomyocytes as Measured by Atomic Force Microscopy Loading-Unloading Curve Analysis.
Atomic force microscopy (AFM) cell loading/unloading curves were used to provide comprehensive insights into biomechanical behavior of cardiomyocytes carrying the lamin A/C (LMNA) D192G mutation known to cause defective nuclear wall, myopathy and severe cardiomyopathy. Our results suggested that the LMNA D192G mutation increased maximum nuclear deformation load, nuclear stiffness and fragility as compared to controls. Furthermore, there seems to be a connection between this lamin nuclear mutation and cell adhesion behavior since LMNA D192G cardiomyocytes displayed loss of AFM probe-to-cell membrane adhesion. We believe that this loss of adhesion involves the cytoskeletal architecture since our microscopic analyses highlighted that mutant LMNA may also lead to a morphological alteration in the cytoskeleton. Furthermore, chemical disruption of the actin cytoskeleton by cytochalasin D in control cardiomyocytes mirrored the alterations in the mechanical properties seen in mutant cells, suggesting a defect in the connection between the nucleoskeleton, cytoskeleton and cell adhesion molecules in cells expressing the mutant protein. These data add to our understanding of potential mechanisms responsible for this fatal cardiomyopathy, and show that the biomechanical effects of mutant lamin extend beyond nuclear mechanics to include interference of whole-cell biomechanical properties.
Department of Engineering and Architecture, University of Trieste, Via Valerio 2, 34127, Trieste Italy.
Thomas
T
Lanzicher
International Center for Genetic Engineering and Biotechnology, Area di Ricerca, Padriciano 99, 34149 Trieste Italy.
Valentina
V
Martinelli
Department of Engineering and Architecture, University of Trieste, Via Valerio 2, 34127, Trieste Italy.
Luca
L
Puzzi
Department of Food Chemistry and Toxicology, University of Vienna, Waehringer Str. 38 A, 1090 Vienna.
Giorgia
G
Del Favero
Department of Engineering and Architecture, University of Trieste, Via Valerio 2, 34127, Trieste Italy.
Barbara
B
Codan
University of Colorado Cardiovascular Institute, University of Colorado Denver AMC, 12700 East 19th Ave. Aurora 80045, Colorado, USA.
Carlin S
CS
Long
University of Colorado Cardiovascular Institute, University of Colorado Denver AMC, 12700 East 19th Ave. Aurora 80045, Colorado, USA.
Luisa
L
Mestroni
University of Colorado Cardiovascular Institute, University of Colorado Denver AMC, 12700 East 19th Ave. Aurora 80045, Colorado, USA.
Matthew R G
MR
Taylor
Department of Engineering and Architecture, University of Trieste, Via Valerio 2, 34127, Trieste Italy.
Orfeo
O
Sbaizero
D000818:Animals; D009202:Cardiomyopathies / Q000378:metabolism / Q000473:pathology; D002448:Cell Adhesion / Q000187:drug effects; D002467:Cell Nucleus / Q000378:metabolism; D002478:Cells, Cultured; D015638:Cytochalasin D / Q000494:pharmacology; D055119:Elastic Modulus; D006801:Humans; D034904:Lamin Type A / Q000235:genetics / Q000378:metabolism*; D018625:Microscopy, Atomic Force; D016296:Mutagenesis; D032383:Myocytes, Cardiac / Q000166:cytology / Q000502:physiology*; D051381:Rats
D034904:Lamin Type A; D015638:Cytochalasin D