eupatilin and Idiopathic-Pulmonary-Fibrosis

Idiopathic pulmonary fibrosis (IPF) is a progressive chronic inflammatory disease with poor clinical outcomes and ineffective drug treatment options. Eupatilin is a major component extracted from the traditional herbal medicine Artemisia asiatica Nakai. Notably, it was demonstrated to have an anti-fibrosis effect in endometrial fibrosis, vocal fold, and hepatic fibrosis. Its role and mechanism in IPF remain unclear.. This study used the TGF-β1-induced human embryonic lung fibroblasts (MRC-5) activation, IPF lung fibroblasts, and bleomycin-induced lung fibrosis mice model. Western blot, immunofluorescence staining, quantitative real time-PCR, hematoxylin and eosin staining, Masson's trichrome staining, and immunohistochemistry were used to evaluate the effects of eupatilin on fibroblast activation, pulmonary fibrosis, and autophagy. The autophagosomes were observed with a transmission electron microscope (TEM). RNA sequencing was used to determine the signaling pathway and key regulator related to autophagy.. Eupatilin significantly decreased the expression of Col1A1, fibronectin, α-SMA, and SQSTM1/p62. In contrast, it increased the expression of LC3B II/I and the number of autophagosomes in TGF-β1 treated MRC-5, IPF lung fibroblasts, and bleomycin-induced lung fibrosis mice model; it also alleviated bleomycin-induced lung fibrosis. The KEGG pathway mapping displayed that PI3K/Akt and Sestrin2 were associated with the enhanced fibrogenic process. Eupatilin suppressed the phosphorylation of PI3K/Akt/mTOR. Autophagy inhibitor 3-methyladenine (3-MA) and Akt activator SC-79 abrogated the anti-fibrotic effect of eupatilin. Sestrin2 expression was also downregulated in TGF-β1 treated lung fibroblasts and lung tissues of the bleomycin-induced pulmonary fibrosis mice model. Furthermore, eupatilin promoted Sestrin2 expression, and the knockdown of Sestrin2 significantly aggravated the degree of fibrosis, increased the phosphorylation of PI3K/Akt/mTOR, and decreased autophagy.. These findings indicate that eupatilin ameliorates pulmonary fibrosis through Sestrin2/PI3K/Akt/mTOR-dependent autophagy pathway.

Topics: Animals; Autophagy; Bleomycin; Fibroblasts; Humans; Idiopathic Pulmonary Fibrosis; Lung; Mice; Phosphatidylinositol 3-Kinases; Proto-Oncogene Proteins c-akt; TOR Serine-Threonine Kinases; Transforming Growth Factor beta1

Myofibroblasts are known to play a key role in the development of idiopathic pulmonary fibrosis (IPF). Two drugs, pirfenidone and nintedanib, are the only approved therapeutic options for IPF, but their applications are limited due to their side effects. Thus, curative IPF drugs represent a huge unmet medical need.. A mouse hepatic stellate cell (HSC) line was established that could robustly differentiate into myofibroblasts upon treatment with TGF-β. Eupatilin was assessed in diseased human lung fibroblasts from IPF patients (DHLFs) as well as in human lung epithelial cells (HLECs). The drug's performance was extensively tested in a bleomycin-induced lung fibrosis model (BLM). Global gene expression studies and proteome analysis were performed.. Eupatilin attenuated disease severity of BLM in both preventative and therapeutic studies. The drug inhibited the in vitro transdifferantiation of DHLFs to myofibroblasts upon stimulation with TGF-β. No such induction of the in vitro transdifferantiation was observed in TGF-β treated HLECs. Specific carbons of eupatilin were essential for its anti-fibrotic activity. Eupatilin was capable of dismantling latent TGF-β complex, specifically by eliminating expression of the latent TGF-β binding protein 1 (LTBP1), in ECM upon actin depolymerization. Unlike eupatilin, pirfenidone was unable to block fibrosis of DHLFs or HSCs stimulated with TGF-β. Eupatilin attenuated phosphorylation of Smad3 by TGF-β. Eupatilin induced myofibroblasts to dedifferentiate into intermediate HCS-like cells.. Eupatilin may act directly on pathogenic myofibroblasts, disarming them, whereas the anti-fibrotic effect of pirfenidone may be indirect. Eupatilin could increase the efficacy of IPF treatment to curative levels.

Topics: Animals; Bleomycin; Cell Differentiation; Cell Line; Cell Transdifferentiation; Disease Models, Animal; Extracellular Matrix; Fibroblasts; Flavonoids; Gene Expression Regulation; Hepatic Stellate Cells; Humans; Idiopathic Pulmonary Fibrosis; Latent TGF-beta Binding Proteins; Mice; Myofibroblasts; Phosphorylation; Smad3 Protein; Transforming Growth Factor beta