Multi-omics analysis unravels dysregulated lysosomal function and lipid metabolism involved in sub-chronic particulate matter-induced pulmonary injury.

Particulate matter (PM) is a huge environmental threat and is of major public concern. Oxidative stress and systemic inflammation are known factors that contribute to PM- related damage; however, a systematic understanding of the deleterious pulmonary effects of PM using multi-omics analysis is lacking. In this study, we performed transcriptomic, proteomic, and metabolomic analyses in a mouse model exposed to PM for three months to identify molecular changes in lung tissues. We identified 1690 genes, 326 proteins, and 67 metabolites exhibiting significant differences between PM-challenged and control mice (p < 0.05). Differentially expressed genes and proteins regulated in PM-challenged mice were involved in lipid metabolism and in the immune and inflammatory response processes. Moreover, a comprehensive analysis of transcript, protein, and metabolite datasets revealed that the genes, proteins, and metabolites in the PM-treated group were involved in lysosomal function and lipid metabolism. Specifically, Cathepsin D (Ctsd), Ferritin light chain (Ftl), Lactotransferrin (Ltf), Lipocalin 2 (Lcn2), and Prosaposin (Psap) were major proteins/genes associated with PM-induced pulmonary damage, while two lipid molecules PC (18:1(11Z)/16:0) and PA (16:0/18:1(11Z)) were major metabolites related to PM-induced pulmonary injury. In summary, lipid metabolism might be used as successful precautions and therapeutic targets in PM-induced pulmonary injury to maintain the stability of cellular lysosomal function.