Multimodal Metabolomics Analysis Reveals That Classic Decoction Mitigates Myocardial Ischemia-Induced Damage by Modulating Energy and Branched-Chain Amino Acid Metabolism

Gualou-Xiebai-Banxia (GXB) decoction shows potential for treating myocardial ischemia (MI), although its underlying mechanism is not fully understood. In this study, a multimodal metabolomics approach, combining gas chromatography–mass spectrometry (GC–MS) and ¹H-NMR, was employed to investigate the cardioprotective effects of GXB in a rat model of myocardial ischemia induced by ligation. ELISA assays and HE staining demonstrated that GXB effectively reduced myocardial injury, oxidative stress markers, and myocardial fibrosis. Orthogonal partial least-squares discriminant analysis identified 62 biomarkers, 20 of which were confirmed using standard compounds. The GC–MS method showed excellent linearity across a wide concentration range (0.004–29.7 μg/mL, R² > 0.9995), with intra- and inter-day precision RSD values below 4.72% and 4.96%, respectively. Method recoveries ranged from 95.40% to 104.83%, with RSD values under 4.84%. Pathway enrichment analysis revealed that GXB decoction alleviates myocardial ischemia-induced damage primarily by modulating energy metabolism and branched-chain amino acid metabolism. These findings provide valuable support for the clinical application of GXB decoction in treating myocardial ischemia.