Fluorofenidone ameliorates pressure overload-induced heart failure by stabilizing SERCA2a in male mice

Abstract

Reduced expression and activity of cardiac sarco/endoplasmic reticulum Ca2+-ATPase 2a (SERCA2a), causing intracellular calcium dyshomeostasis, are regarded as hallmarks of heart failure (HF). However, effective SERCA2a-targeted therapies for HF treatment have not been identified. Here, we show that fluorofenidone, previously reported to enhance cell shortening, contraction and relaxation of cardiomyocytes by nearly 100%, prevents the progression of pressure overload-induced HF. Combining drug affinity responsive target stability (DARTS), cellular thermal shift assay (CETSA) and surface plasmon resonance (SPR) approaches, we identify SERCA2a as a direct binding partner of fluorofenidone. Mechanistically, fluorofenidone attenuates the binding of WW domain-containing E3 ubiquitin protein ligase 1 (WWP1) to SERCA2a and inhibits WWP1-mediated K27-linked polyubiquitination of SERCA2a. Moreover, Gln758, Asp812 and Glu917 are essential for the fluorofenidone-SERCA2a interaction. SERCA2a knockdown markedly attenuated the cardioprotective effects of fluorofenidone on pressure overload-induced HF in male mice. Together, these findings highlight the therapeutic potential of fluorofenidone for HF treatment. Nevertheless, further preclinical and clinical studies are required to fully evaluate its in vivo efficacy and safety before clinical translation. Reduced expression and activity of cardiac sarco/endoplasmic reticulum Ca2 + -ATPase 2a (SERCA2a) are regarded as hallmarks of heart failure. Here, the authors show how the SERCA2a-targeted small-molecule agent fluorofenidone protects against pressure overload-induced heart failure.