Exploring the Underlying Mechanisms of Aerobic Exercise-Improving Cardiovascular Function by Integrating Microbiome, Metabolome, and Proteome Analysis in a High-Fat Diet-Induced Obesity Rat Model

Objective: This study aimed to investigate the potential mechanisms by which moderate-intensity aerobic exercise improves cardiovascular dysfunction in high-fat diet-induced obese rats through integrated multi-omics analysis. Methods: Rats were divided into a normal diet group, a high-fat diet group, and a high-fat diet with exercise group. Cardiovascular function was assessed by echocardiography and vascular tension measurement. Gut microbiota, serum metabolites, and protein expression were analyzed using 16S rRNA sequencing, untargeted metabolomics, and proteomics, respectively. Integrated multi-omics analysis was performed using Mantel tests and mediation effect analysis. Results: Eight weeks of aerobic exercise significantly improved cardiovascular function in obese rats, including enhanced acetylcholine-induced vasodilation and increased left ventricular ejection fraction. Furthermore, exercise remodeled the gut microbiota structure, such as altering the abundance of Lactobacillus and Ruminiclostridium_9. Metabolomics revealed that exercise shifted the metabolic phenotype from high-fat diet-induced basal metabolic disorder toward beneficial pathways, including fatty acid biosynthesis and ubiquinone biosynthesis. Proteomics identified key differentially expressed proteins such as APOE, FN1, and Lap3. Integrated multi-omics analysis for the first time revealed a core regulatory axis: exercise may influence Lap3 expression, modulate the abundance of intestinal Lactobacillus, and thereby systematically regulate the level of palmitoyllysophosphatidylcholine, ultimately improving cardiovascular function. Conclusion: Aerobic exercise improves high-fat diet-induced cardiovascular dysfunction by systematically remodeling the gut microbiota–host metabolism–protein expression network. The discovery of the Lap3–Lactobacillus–palmitoyllysophosphatidylcholine axis provides new molecular insights into the exercise-mediated protective mechanisms of the gut–cardiovascular system axis.