Andrographolide ameliorates bleomycin-induced pulmonary fibrosis by suppressing cell proliferation and myofibroblast differentiation of fibroblasts via the TGF-β1-mediated Smad-dependent and -independent pathways.

Idiopathic pulmonary fibrosis (IPF) is a progressive lung disease with no effective medication. Andrographolide (Andro), extracted from Chinese herbal Andrographis paniculata, could attenuate bleomycin (BLM)-induced pulmonary fibrosis via inhibition of inflammation and oxidative stress, however, the anti-fibrotic mechanisms have not been clarified. Myofibroblasts are the primary cell types responsible for the accumulation of extracellular matrix (ECM) in fibrotic diseases, and targeting fibroblast proliferation and differentiation is an important therapeutic strategy for the treatment of IPF. Hence, this study aimed to investigate the effects of Andro on the fibroblast proliferation and differentiation in the in vivo and in vitro models. The results showed that Andro improved pulmonary function and inhibited BLM-induced fibroblast proliferation and differentiation and ECM deposition in the lungs. In vitro, Andro inhibited proliferation and induced apoptosis of TGF-β1-stimulated NIH 3T3 fibroblasts and primary lung fibroblasts (PLFs). Andro also inhibited TGF-β1-induced myofibroblast differentiation and ECM deposition in both cells. We also found that Andro suppressed TGF-β1-induced Smad2/3 and Erk1/2 activation, suggesting that Smad2/3 and Erk1/2 inactivation mediates Andro-induced effects on TGF-β1-induced fibroblast proliferation and differentiation. These results indicated that Andro has novel and potent anti-fibrotic effects in lung fibroblasts via inhibition of the proliferation and myofibroblast differentiation of fibroblasts and subsequent ECM deposition, which are modulated by TGF-β1-mediated Smad-dependent and -independent pathways.

Li J ，Feng M ，Sun R ，Li Z ，Hu L ，Peng G ，Xu X ，Wang W ，Cui F ，Yue W ，He J ，Liu J ... -  《-》

Sequential analysis of myofibroblast differentiation and transforming growth factor-β1/Smad pathway activation in murine pulmonary fibrosis.

Usuki J ，Matsuda K ，Azuma A ，Kudoh S ，Gemma A ... -  《-》

Emodin ameliorates bleomycin-induced pulmonary fibrosis in rats by suppressing epithelial-mesenchymal transition and fibroblast activation.

Guan R ，Wang X ，Zhao X ，Song N ，Zhu J ，Wang J ，Wang J ，Xia C ，Chen Y ，Zhu D ，Shen L ... -  《Scientific Reports》

Biochanin-A ameliorates pulmonary fibrosis by suppressing the TGF-β mediated EMT, myofibroblasts differentiation and collagen deposition in in vitro and in vivo systems.

Idiopathic Pulmonary Fibrosis (IPF) is a progressive inflammatory disorder driven by a fibrotic cascade of events such as epithelial to mesenchymal transition, extracellular matrix production and collagen formation in the lungs in a sequential manner. IPF incidences were raising rapidly across the world. FDA approved pirfenidone and nintedanib (tyrosine kinase inhibitors) are being used as a first-line treatment drugs for IPF, however, neither the quality of life nor survival rates have been improved because of patient noncompliance due to multiple side effects. Thus, the development of novel therapeutic approaches targeting TGF-β mediated cascade of fibrotic events is urgently needed to improve the survival of the patients suffering from devastating disease. The aim of this study was to investigate and validate the anti-fibrotic properties of Biochanin-A (isoflavone) against TGF-β mediated fibrosis in in vitro, ex vivo, in vivo models and to determine the molecular mechanisms that mediate these anti-fibrotic effects. The therapeutic activity of BCA was determined in in vitro/ex vivo models. Cells were pre-treated with BCA and incubated in presence or absence of recombinant-TGF-β to stimulate the fibrotic cascade of events. Pulmonary fibrosis was developed by intratracheal administration of bleomycin in rats. BCA treatment was given for 14 days from post bleomycin instillation and then various investigations (collagen content, fibrosis gene/protein expression and histopathological changes) were performed to assess the anti-fibrotic activity of BCA. In vitro/ex vivo (Primary normal, IPF cell line and primary IPF cells/ Precision cut mouse lung slices) experiments revealed that, BCA treatment significantly (p < 0.001) reduced the expression of TGF-β modulated fibrotic genes/protein expressions (including their functions) which are involved in the cascade of fibrotic events. BCA treatment significantly (p < 0.01) reduced the bleomycin-induced inflammatory cell-infiltration, inflammatory markers expression, collagen deposition and expression of fibrotic markers in lung tissues equivalent or better than pirfenidone treatment. In addition, BCA treatment significantly (p < 0.001) attenuated the TGF-β1/BLM-mediated increase of TGF-β/Smad2/3 phosphorylation and resulted in the reduction of pathological abnormalities in lung tissues determined by histopathology observations. Collectively, BCA treatment demonstrated the remarkable therapeutic effects on TGF-β/BLM mediated pulmonary fibrosis using IPF cells and rodent models. This current study may offer a novel treatment approach to halt and may be even rescue the devastating lung scarring of IPF.

Andugulapati SB ，Gourishetti K ，Tirunavalli SK ，Shaikh TB ，Sistla R ... -  《-》

Metformin attenuates lung fibrosis development via NOX4 suppression.

Sato N ，Takasaka N ，Yoshida M ，Tsubouchi K ，Minagawa S ，Araya J ，Saito N ，Fujita Y ，Kurita Y ，Kobayashi K ，Ito S ，Hara H ，Kadota T ，Yanagisawa H ，Hashimoto M ，Utsumi H ，Wakui H ，Kojima J ，Numata T ，Kaneko Y ，Odaka M ，Morikawa T ，Nakayama K ，Kohrogi H ，Kuwano K ... -  《RESPIRATORY RESEARCH》