Spatial Resolved Metabolomics via AFADESI-MSI Reveals Lipid Metabolic Alterations in Aging Lungs

Background : The global burden of age-related respiratory diseases—most notably COPD and IPF—has reached unprecedented levels. Understanding the unique metabolic profiles of lung tissue is essential for elucidating the molecular mechanisms of natural lung aging. However, the spatially resolved metabolic drivers of pulmonary aging remain uncharacterized. We employed airflow-assisted desorption electrospray ionization mass spectrometry imaging (AFADESI-MSI) to map lipid dysregulation in aging lungs. Methods : Lung tissues from young (3-month) and aged (24-month) C57BL/6J mice were analyzed using AFADESI-MSI for spatially resolved metabolomics. Key findings were validated by LC-MS/MS and immunohistochemical analysis of metabolic enzymes. Results : AFADESI-MSI revealed compartmentalized lipid remodeling in aged lungs, particularly in unsaturated fatty acid and arachidonic acid metabolism, showing significant perturbations. High-resolution spatial mapping demonstrated distinct distribution patterns of these metabolites. LC-MS/MS validation confirmed reduced levels of adrenic acid and palmitic acid, alongside elevated levels of 12-ketotetrahydroleukotriene B4, indicating pro-inflammatory and oxidative stress progression in lung aging. Additionally, five key metabolic enzymes (ELOVL, FABP6, LTA4H, PLA2, and PTGR1) associated with these metabolites exhibited altered expression patterns in aged mouse lungs. Conclusion : Our study highlights the potential of AFADESI-MSI as an innovative tool for metabolic biomarker research and suggests directions for future multi-omics and functional validation studies. Spatially resolved metabolomics approach uncovered multilevel molecular alterations during lung aging, offering insights into the metabolic reprogramming of unsaturated fatty acid and arachidonic acid pathways. These findings demonstrate that adrenic acid-LTB4 imbalance drives pro-inflammatory microenvironments in lung aging.