B100-07 Metabolome-wide Association Study Identifies Fatty Acid and Oxidative Stress Perturbations in Mesenchymal Cells From Subjects With Chronic Lung Allograft Dysfunction

Rationale Chronic lung allograft dysfunction (CLAD) is a life-threatening complication in lung-transplant recipients with few effective treatments. Prior studies have identified multiple signaling pathways that converge to disrupt translational regulation in mesenchymal cells (MCs), thus promoting their pro-fibrotic transformation in CLAD. Given that these pathways are activated via phosphorylation of key protein kinases, the inefficient ATP generation due to specific metabolic perturbations that sustain this reprogramming in CLAD MCs remains poorly defined. High-resolution metabolomics now offers a comprehensive approach to mapping these metabolic alterations. Hypothesis: Disruptions in lipid and fatty acid metabolism lead to increased oxidative stress, mitochondrial dysfunction, and pro-fibrotic signaling in CLAD MCs. Methods MCs were cultured from lung transplant recipients with and without CLAD. High-resolution metabolomics analyses were performed at Emory University’s Clinical Biomarkers Lab using tandem mass spectrometry coupled to liquid chromatography with dual-column electrospray ionization (HILIC with ESI+ and C18 with ESI-) to achieve detailed global metabolic profiling. Feature extraction was conducted using the R packages apLCMS and xMSanalyzer, yielding over 20,000 mass-to-charge (m/z) features. Pathway analysis was conducted with Mummichog, and metabolite annotation was utilized with xMSannotator. Comprehensive bioinformatics analysis was performed using xmsPANDA. Results High-Resolution Metabolomics identified 18,764 features for analysis. A metabolome-wide association study (MWAS) using LIMMA analysis (p < 0.05) and hierarchical clustering identified 1,121 features that differed significantly between CLAD and non-CLAD MCs (n = 10 CLAD; n = 7 non-CLAD). Volcano plot analysis showed 741 features elevated and 380 reduced in CLAD. Pathway analysis revealed perturbations in 15 metabolic pathways, including fatty acid metabolism (8 pathways), xenobiotic metabolism (2 pathways), and additional pathways related to cell signaling, immune response, and inflammation (5 pathways). Crucial pathways identified include fatty acids, carnitine shuttle, glycosphingolipids, xenobiotics, and amino acids (valine, leucine, isoleucine). Conclusions Our results indicate systemic metabolic disruptions in fatty acid utilization, energy metabolism, and cellular signaling in CLAD MCs. Changes in fatty acid metabolism are associated with increased oxidative stress, mitochondrial dysfunction, and pro-fibrotic signaling. Overall, these insights advance our understanding of pro-fibrotic metabolism in CLAD and reveal potential therapeutic interventions within cellular metabolism.