CYBB and obesity due to melanocortin 4 receptor deficiency: Treatment of DIO and DIO Nox2-KO mice with a generic NOX blocker, apocynin, and of PA-treated hiPSC-aCMs with a NOX2-specific inhibitor, GSK2795039, abrogated obesity-mediated ion channel remodeling and atrial fibrosis by reducing oxidative stress and ROS production.