RT Journal Article T1 Single-Cell RNA Sequencing Analysis Reveals a Crucial Role for CTHRC1 (Collagen Triple Helix Repeat Containing 1) Cardiac Fibroblasts After Myocardial Infarction A1 Ruiz-Villalba, Adrián A1 Romero, Juan P A1 Hernandez, Silvia C A1 Vilas-Zornoza, Amaia A1 Fortelny, Nikolaus A1 Castro-Labrador, Laura A1 San Martin-Uriz, Patxi A1 Lorenzo-Vivas, Erika A1 Garcia-Olloqui, Paula A1 Palacio, Marcel A1 Gavira, Juan José A1 Bastarrika, Gorka A1 Janssens, Stefan A1 Wu, Ming A1 Iglesias, Elena A1 Abizanda, Gloria A1 Martinez de Morentin, Xabier A1 Lasaga, Miren A1 Planell, Nuria A1 Bock, Christoph A1 Alignani, Diego A1 Medal, Gema A1 Prudovsky, Igor A1 Jin, Yong-Ri A1 Ryzhov, Sergey A1 Ying, Haifeng A1 Pelacho, Beatriz A1 Gómez-Cabrero, David A1 Lindner, Volkdhard A1 Lara-Astiaso, David A1 Prósper, Felipe K1 Biología animal K1 Fibrosis AB Background: Cardiac fibroblasts (CFs) have a central role in the ventricular remodeling process associated with different types of fibrosis. Recent studies have shown that fibroblasts do not respond homogeneously to heart injury. Because of the limited set of bona fide fibroblast markers, a proper characterization of fibroblast population heterogeneity in response to cardiac damage is lacking. The purpose of this study was to define CF heterogeneity during ventricular remodeling and the underlying mechanisms that regulate CF function.Methods: Collagen1α1-GFP (green fluorescent protein)-positive CFs were characterized after myocardial infarction (MI) by single-cell and bulk RNA sequencing, assay for transposase-accessible chromatin sequencing, and functional assays. Swine and patient samples were studied using bulk RNA sequencing.Results: We identified and characterized a unique CF subpopulation that emerges after MI in mice. These activated fibroblasts exhibit a clear profibrotic signature, express high levels of Cthrc1 (collagen triple helix repeat containing 1), and localize into the scar. Noncanonical transforming growth factor-β signaling and different transcription factors including SOX9 are important regulators mediating their response to cardiac injury. Absence of CTHRC1 results in pronounced lethality attributable to ventricular rupture. A population of CFs with a similar transcriptome was identified in a swine model of MI and in heart tissue from patients with MI and dilated cardiomyopathy.Conclusions: We report CF heterogeneity and their dynamics during the course of MI and redefine the CFs that respond to cardiac injury and participate in myocardial remodeling. Our study identifies CTHRC1 as a novel regulator of the healing scar process and a target for future translational studies. YR 2020 FD 2020 LK https://hdl.handle.net/10630/33732 UL https://hdl.handle.net/10630/33732 LA eng DS RIUMA. Repositorio Institucional de la Universidad de Málaga RD 21 ene 2026