Metabolomics analysis and mRNA/miRNA profiling reveal potential cardiac regulatory mechanisms in Yili racehorses under different training regimens.
Authors: Wang Tongliang, Meng Jun, Peng Xuan, Huang Jinlong, Huang Yunjiang, Yuan Xinxin, Li Xueyan, Yang Xixi, Chang Xiaokang, Zeng Yaqi, Yao Xinkui
Journal: PloS one
Summary
Yili horses, a Chinese racing breed with considerable athletic potential, demonstrate clear cardiac adaptations to training, yet the underlying molecular mechanisms driving these changes remain poorly characterised. Researchers employed a comprehensive multi-omics approach—combining echocardiography, RNA sequencing, and metabolomic profiling—to investigate how training intensity shapes cardiac structure, gene expression, and metabolic status across high-level trained, moderately trained, and untrained horses. Trained animals showed significant cardiac remodelling including increased left ventricular mass, altered septal thickness, and changed ventricular dimensions; at the molecular level, 534 differentially expressed genes and 366 differentially expressed miRNAs were identified, with particular enrichment in pathways governing glycine/serine/threonine metabolism, oxygen transport capacity (notably ALAS2 for haem synthesis), and ATP production, whilst metabolomic shifts revealed training-related changes in acylcarnitine and triglyceride profiles indicating altered energy substrate utilisation. These findings suggest that miRNA-mediated regulation of cardiac remodelling and metabolic reallocation represents a critical adaptive mechanism to training load. For practitioners, this research underpins a molecular rationale for individualising training programmes and monitoring protocols based on each horse's metabolic and transcriptomic profile, potentially allowing earlier identification of excessive training stress or suboptimal cardiac adaptation before overt performance decline occurs.
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Practical Takeaways
- •Cardiac structural changes (increased left ventricular mass) are expected adaptive responses in trained racehorses; use echocardiography to monitor training progression and identify abnormal remodeling patterns
- •Metabolic profiling (acylcarnitine and triglyceride levels) may provide objective biomarkers to optimize individual training intensity and recovery protocols
- •Understanding molecular pathways controlling cardiac adaptation could help tailor conditioning programs to maximize performance while reducing risk of overtraining or cardiac dysfunction
Key Findings
- •Trained Yili horses showed increased left ventricular mass with significant differences in intraventricular septal thickness and left ventricular end-diastolic diameter compared to untrained horses
- •RNA sequencing identified 534 differentially expressed genes and 366 differentially expressed miRNAs, with enrichment in glycine/serine/threonine metabolism and oxygen transport pathways
- •Metabolomic analysis revealed training-related variations in acylcarnitine and triglyceride profiles, suggesting metabolic remodeling linked to cardiac adaptation
- •miRNA regulation appears to coordinate training-induced cardiac remodeling and metabolic changes related to ATP generation and oxygen transport