Farfarae Flos Mitigates Cigarette Smoking-Induced Lung Inflammation by Regulating the Lysophosphatidylcholine Biosynthesis and Tryptophan Metabolism

An increased risk of developing respiratory diseases has been linked to exposure to cigarette smoking (CS). The flower buds of Tussilago farfara L., also known as Farfarae Flos (FF), can be used for the treatment of cough, bronchitis, and asthmatic disorders in China. In the present study, we used lung and fecal metabolomics, as well as the intestinal flora analysis, aimed to investigate the protective effect of FF against the CS exposure induced lung inflammation on mice. The results showed that FF administration could relieve the lung inflammation as demonstrated by lung index, interleukin-6 (IL-6), and interleukin-1β (IL-1β) levels, as well as the pulmonary pathological change. The lung metabolomics coupled with molecular docking showed that FF could alleviate lung inflammation by regulating lysophosphatidylcholine biosynthesis through the caffeoyl quinic acids distributed in the lung tissue. In addition, fecal metabolome coupled with 16S rRNA gene sequencing showed that FF could regulate the tryptophan metabolism by regulating the intestinal flora disorders. This study provided new insights of FF to relieve CS-induced pulmonary inflammation with the multimechanism.