Qilongtian Ameliorate Bleomycin-induced Pulmonary Fibrosis in Mice via Inhibiting IL-17 signal pathway

Abstract

Abstract Pulmonary fibrosis (PF) is a special type of pulmonary parenchymal disease, with chronic, progressive, fibrosis, high mortality. There is a lack of safe, effective, and affordable treatment methods. Qilongtian (QLT) is a traditional Chinese prescription that is composed of Panax notoginseng, Earthworm, and Rhodiola, and shows the remarkable clinical curative effect of PF. However, the mechanism of QLT remains to be clarified. Therefore, we studied the effectivity of QLT in treating Bleomycin (BLM) induced PF mice. Our studies have shown that QLT significantly reduced the inflammatory injury, hydroxyproline content and collagen deposition of lung tissue in BLM induced PF mice and downregulated the cytokine related to inflammation and fibrosis and PF expression on the mRNA and protein level in PF mice. To identify the mechanism of QLT, the Transcriptome was measured, and the IL-17 signal pathway was screened out for further research. Further studies indicated that QLT reduced the mRNA level of CCL12, CXCL5, FOSL1, MMP9, and AREG, which are inflammation and fibrosis-related genes in the IL-17 signal pathway. In summary, the results indicated that the potential mechanism of QLT in preventing PF progress was by inhibiting the inflammation resulting in IL-17 signal pathway. Our study provides the novel scientific basis of QLT and represents new therapeutics for PF in clinical.