title: Hypertrophic phenotype in cardiac cell assemblies solely by structural cues and ensuing self-organization.
abstract: In vitro models of cardiac hypertrophy focus exclusively on applying "external" dynamic signals (electrical, mechanical, and chemical) to achieve a hypertrophic state. In contrast, here we set out to demonstrate the role of "self-organized" cellular architecture and activity in reprogramming cardiac cell/tissue function toward a hypertrophic phenotype. We report that in neonatal rat cardiomyocyte culture, subtle out-of-plane microtopographic cues alter cell attachment, increase biomechanical stresses, and induce not only structural remodeling, but also yield essential molecular and electrophysiological signatures of hypertrophy. Increased cell size and cell binucleation, molecular up-regulation of released atrial natriuretic peptide, altered expression of classic hypertrophy markers, ion channel remodeling, and corresponding changes in electrophysiological function indicate a state of hypertrophy on par with other in vitro and in vivo models. Clinically used antihypertrophic pharmacological treatments partially reversed hypertrophic behavior in this in vitro model. Partial least-squares regression analysis, combining gene expression and functional data, yielded clear separation of phenotypes (control: cells grown on flat surfaces; hypertrophic: cells grown on quasi-3-dimensional surfaces and treated). In summary, structural surface features can guide cardiac cell attachment, and the subsequent syncytial behavior can facilitate trophic signals, unexpectedly on par with externally applied mechanical, electrical, and chemical stimulation.
authors.affiliation: Department of Biomedical Engineering, Stony Brook University, Stony Brook, NY 11794-8181, USA.
authors.forename: Chiung-yin
authors.initials: CY
authors.lastname: Chung
authors.forename: Harold
authors.initials: H
authors.lastname: Bien
authors.forename: Eric A
authors.initials: EA
authors.lastname: Sobie
authors.forename: Vikram
authors.initials: V
authors.lastname: Dasari
authors.forename: David
authors.initials: D
authors.lastname: McKinnon
authors.forename: Barbara
authors.initials: B
authors.lastname: Rosati
authors.forename: Emilia
authors.initials: E
authors.lastname: Entcheva
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D009320:Atrial Natriuretic Factor / Q000235:genetics / Q000378:metabolism; D006332:Cardiomegaly / Q000378:metabolism / Q000473:pathology / Q000503:physiopathology; D002448:Cell Adhesion / Q000502:physiology; D048430:Cell Shape / Q000502:physiology; D002478:Cells, Cultured; D004558:Electric Stimulation; D005819:Genetic Markers; D040542:Mechanotransduction, Cellular / Q000502:physiology; D009200:Myocardial Contraction / Q000502:physiology*; D032383:Myocytes, Cardiac / Q000166:cytology* / Q000187:drug effects / Q000502:physiology*; D020097:Natriuretic Peptide, Brain / Q000494:pharmacology; D010641:Phenotype; D010812:Physical Stimulation; D051381:Rats; D015398:Signal Transduction / Q000502:physiology*; D013268:Stimulation, Chemical; D054457:Tissue Scaffolds
chemical_list: D005819:Genetic Markers; D020097:Natriuretic Peptide, Brain; D009320:Atrial Natriuretic Factor