Abstract 15308: NLRP3 Activation and Calcium-Dependent Contractile Function in Rat Right Ventricle Cardiomyocytes (RVCMs) Are Sexually Dimorphic and Controlled by 17β-Estradiol-via Estrogen Receptor-α

• Published in: Circulation (New York, N.Y.) N.Y.), 2023-11, Vol.148 (Suppl_1)
• Main Authors: Sobrano Fais, Rafael, Hoffer, Christopher, Moreno Vinasco, Liliana, Walts, Avram, Cook, Todd, Fisher, Amanda, Frump, Andrea L, Woulfe, KC, Lahm, Tim
• Format: Article
• Language: English
• ISSN: 0009-7322; 1524-4539
• DOI: 10.1161/circ.148.suppl_1.15308

Abstract only Introduction: NLRP3 inflammasome activation promotes right ventricle (RV) contractile dysfunction in pulmonary hypertension (PH). However, the role of NLRP3 signaling in RVCMs has not been studied. 17β-estradiol (E2) improves RVCM function in PH. Hypothesis: E2, via estrogen receptor-α (ERα), prevents RVCM NLRP3 inflammasome activation and contractile dysfunction in experimental PH. Methods: RV failure in male and female Sprague Dawley rats were induced with monocrotaline (MCT). Co-localization of NLRP3 and its partner ASC was assessed. RVCMs isolated from healthy male or female wildtype (WT) or ERα loss of function mutant (ERα mut ) rats were treated with NLRP3 activators lipopolysaccharide (LPS 1 μg/mL, 4 h) and ATP (2 mM, 10 min) ± E2 (1 nM, 24 h) or NLRP3 inhibitor MCC950 (1 μM, 30 min). RVCM contractility and Ca 2+ levels were evaluated via IONOPTIX system. Protein levels of NLRP3 and its targets were assessed. ERα binding to the NLRP3 promoter was assessed by immunoprecipitation. RNA-seq was performed in RV tissues from male and intact or ovariectomized female rats with RV failure. Results: RNA-seq demonstrated that transcripts involved in NLRP3 activation are E2-regulated. RVCMs from male, but not female, MCT rats showed increased NLRP3 and ASC co-localization/activation (p