Identification and Transcriptomic Analysis of Mitochondria-Related Gene Signatures in Obesity

Objectives: This study aimed to identify core genes associated with mitochondria-related transcriptomic signatures and evaluate their potential as computational biomarkers, immune characteristics, regulatory mechanisms, and potential therapeutic relevance. Methods: Obesity-related transcriptome datasets were obtained from the GEO database. Differentially expressed genes (DEGs) were intersected with mitochondria-related genes (MRGs) to identify obesity-related MRGs. Functional enrichment, protein-protein interaction (PPI) analysis, CytoHubba, LASSO and random forest algorithms were used to screen core genes. External validation, ROC analysis, immune infiltration analysis, regulatory network construction, candidate drug prediction, and molecular docking were further performed. Results: A total of 527 DEGs and 15 differentially expressed MRGs were identified. Enrichment analysis suggested that these mitochondria-related genes were mainly associated with disrupted mitochondrial energy metabolism, lipid metabolic remodeling, and altered substrate utilization. ECHDC2, FASN, NAT8L, and AASS were identified as core MRGs; these genes are respectively associated with mitochondrial metabolic regulation, de novo fatty acid synthesis, N-acetylaspartate-related mitochondrial metabolism, and lysine degradation. These genes were significantly downregulated in obesity and showed good diagnostic performance. Immune infiltration analysis revealed alterations in the immune microenvironment, and the core genes were negatively correlated with multiple immune cell types. Molecular docking showed that Genistein had the lowest predicted binding free energy with NAT8L (-8.89 kcal/mol), suggesting relatively favorable binding among the tested ligand-target pairs. Conclusions: ECHDC2, FASN, NAT8L, and AASS may serve as candidate computational biomarkers, among which FASN represents a known lipid metabolism-related gene, supporting the biological plausibility of the workflow.