Multi-omics analysis of the protective effects of Platycodon grandiflorum -derived inulin-type fructan against low-concentration PM_2.5-induced lung microenvironment changes in rats

In northern China, haze events frequently occur during winter, and PM_2.5 is recognized as the most significant particulate matter in haze, posing a major threat to human health. Therefore, we employed a PM_2.5 inhalation exposure system to investigate the protective effects of Platycodon grandiflorum inulin-type fructan (PGPI-1-a) on low-concentration PM_2.5-induced lung microenvironment changes. Our findings revealed that long-term (4-month) PM_2.5 exposure did not cause apparent pathological alterations in rat lungs but induced lung inflammation, which was alleviated by PGPI-1-a intervention. Multi-omics analysis demonstrated that PGPI-1-a restored abnormally expressed lung proteins, improved lung microbiota disorders, and regulated serum metabolite imbalances related to lipid and amino acid metabolism, ameliorating low-concentration PM_2.5-induced lung microenvironment changes. These results suggest that Platycodon grandiflorum inulin-type fructan could serve as a potential dietary supplement for mitigating PM_2.5-induced lung injury.