In rat AF models and clinical studies, honey-fried licorice decoction, a traditional preparation used in Chinese herbal medicine, downregulated NOX2 expression and RONS in atrial tissue, restored antioxidant enzyme balance (SOD, CAT, GSH/GSSG), reduced TGF β1/SMAD3 signaling, and decreased AF susceptibility [42]. Here, SMAD3 is linked to atrial fibrillation.