Integrated analysis of transcriptome and metabolome reveal the complex molecular regulatory network of chicken house PM2.5 induced lung injury.

Fine particulate matter (PM2.5) in poultry houses is the main component of air pollution. Long-term exposure to high concentrations of PM2.5 could easily damage the respiratory system of animals. In this study, we first investigated the changes in lung tissue morphology and serum cytokines in SPF chickens after exposure to poultry house PM2.5 and further conduct a combined analysis of its lung transcriptome and metabolome. The results showed that chicken exposed to PM2.5 led to decrease in body weight and cause inflammatory damage such as pulmonary fibrosis in chickens. It also significantly upregulated the expression levels of serum cytokines IL-1β, IL-6, TLR-2, TLR-4, IFN-α, TGF-β and CCL2. Additionally, it affected Arachidonic acid metabolism, Ferroptosis, and mTOR signaling pathways, disrupting metabolic processes and the expression of genes related to pulmonary inflammation. In addition, we validated the results of the multi-omics combined analysis and found that the interaction between the differential metabolite Arachidonic acid and the three differentially expressed genes LTA4H, FTL and PLA2G4A led to pulmonary inflammatory damage and metabolic disorders. The above results indicate that the interaction between pulmonary inflammation-related genes and lung metabolites may play a crucial role in the process of PM2.5-induced lung injury in chickens.