Activation of PDGFRA signaling contributes to filamin C-related arrhythmogenic cardiomyopathy.

Abstract

FLNC truncating mutations (FLNCtv) are prevalent causes of inherited dilated cardiomyopathy (DCM), with a high risk of developing arrhythmogenic cardiomyopathy. We investigated the molecular mechanisms of mutant FLNC in the pathogenesis of arrhythmogenic DCM (a-DCM) using patient-specific induced pluripotent stem cell-derived cardiomyocytes (iPSC-CMs). We demonstrated that iPSC-CMs from two patients with different FLNCtv mutations displayed arrhythmias and impaired contraction. FLNC ablation induced a similar phenotype, suggesting that FLNCtv are loss-of-function mutations. Coimmunoprecipitation and proteomic analysis identified β-catenin (CTNNB1) as a downstream target. FLNC deficiency induced nuclear translocation of CTNNB1 and subsequently activated the platelet-derived growth factor receptor alpha (PDGFRA) pathway, which were also observed in human hearts with a-DCM and FLNCtv. Treatment with the PDGFRA inhibitor, crenolanib, improved contractile function of patient iPSC-CMs. Collectively, our findings suggest that PDGFRA signaling is implicated in the pathogenesis, and inhibition of this pathway is a potential therapeutic strategy in FLNC-related cardiomyopathies.

• Authors: Suet Nee Chen, Chi Keung Lam, Ying-Wooi Wan, Shanshan Gao, Olfat A Malak, Shane Rui Zhao, Raffaella Lombardi, Amrut V Ambardekar, Michael R Bristow, Joseph Cleveland, Marta Gigli, Gianfranco Sinagra, Sharon Graw, Matthew R G Taylor, Joseph C Wu, Luisa Mestroni
• Journal: Science advances (Sci Adv) Vol. 8 Issue 8 Pg. eabk0052 (Feb 25 2022) ISSN: 2375-2548 [Electronic] United States
• PMID: 35196083 (Publication Type: Journal Article)