Prodigiosin Alleviates Pulmonary Fibrosis Through Inhibiting miRNA-410 and TGF-β1/ADAMTS-1 Signaling Pathway

Abstract

Background/Aims: Pulmonary fibrosis is a common outcome of various interstitial lung diseases. Prodigiosin (PG) is a series of red pigment with methoxypyrrole ring. This studyinvestigates therole of prodigiosin in pulmonary fibrosis and its underlying mechanisms. Methods: A pulmonary fibrosis rat model was established by intra-trachealinjection ofbleomycin A5. Rats were divided into 4 groups: Normal group, pulmonary fibrosis Model group, Prodigiosin treatment group and hydrocortisone treatmentgroup. HE and Masson staining were carried outto evaluate histopathological changes. The content of hydroxyproline in lung tissue was determined by alkaline hydrolysis. The expression of PICP and PIIINP was examined by ELISA. The mRNA expression of miR-410, TGF-β1 and ADAMTS1 in lung homogenate were detected by RT-PCR. The bronchoalveolar lavage fluid (BALF) and lung tissues of rats were collected and analyzed. Human embryonic pulmonary fibroblast (HEPF) was used for study in vitro. A dual-luciferase reporter assay was conducted to examine the effect of miR-410 on ADAMTS1 expression. Cell transfection was conducted to inhibit miR-410. MTT assay was performed to investigate cell proliferation. The expressions of miR-410, TGF-β1, ADAMTS1and other fibrosis related biomarkers (Col I, Col III, and α-SMA) wereexamined by RT-PCR and Western Blot. Results: HE and Masson staining showed thickened alveolar septum, hyperplasticcapillaries, and large areas of collagen fiber deposition in pulmonary fibrosis model rats. Rats in prodigiosin and hydrocortisone treatment groups had alleviated symptoms. There was high hydroxyproline expression in model rats, whereas the expression of hydroxyproline reduced after prodigiosin or hydrocortisone treatments. RT-PCR results showed high miR-410,high TGF-β1 and low ADAMTS1 in lung tissue of model rats. The expression of PICP and PIIINP werehigher in BALF of model group than in treatment groups. Prodigiosin and hydrocortisone treatment significantly reduced PICP and PIIINP content. RT-PCR and Western Blot analysis showed that prodigiosin inhibited expression of miR-410 and TGF-β1, but up-regulated ADAMTS1 expression. MTT assay indicated that prodigiosin inhibited HEPF proliferation induced by miR-410 overexpression. Conclusion: Prodigiosin down-regulates the expression of miR-410 and TGF-β1, up-regulates ADAMTS1, leading to decrease accumulation of fibrotic proteins. It could be used in alleviating pulmonary fibrosis.