Multi-Omics Analysis Reveals Biaxial Regulatory Mechanisms of Cardiac Adaptation by Specialized Racing Training in Yili Horses

Yili horses undergo coordinated physiological adaptations across systems in response to customized training. This study aimed to clarify the molecular mechanisms of these adaptations by integrating analyses of cardiac function and multi-omics (lipidomics, transcriptomics, miRNomics). We collected whole blood samples from ten Yili horses before and after 12 weeks of specialized racing training to perform these analyses. Results showed training induced adaptive cardiac remodeling, with substantial increases in LVIDd and LVIDs. At the molecular level, this was accompanied by extensive blood lipid reprogramming (383 differential lipids), enriched in energy pathways like fatty acid metabolism. Transcriptomic analysis identified 851 differential genes, also enriched in energy-related pathways (e.g., oxidative phosphorylation). We constructed a miRNA–mRNA network (189 pairs), finding miRNAs such as miR-150 and miR-199b regulate key energy-supply mRNAs. Integrated analyses revealed precise modulation of pathways: (1) eca-miR-150 is associated with AZIN1 and creatine, with potential links to arginine/proline metabolism; (2) miR-8903 is associated with LRAT and nicotinamide, with potential associations with vitamin absorption. These pathways are critical for energy metabolism, redox balance, and signal transduction. Overall, this study reveals how training optimizes energy supply and metabolic homeostasis in Yili horses, offering new insights into training adaptation physiology.