scholarly journals Sequential expression of IGF-IB followed by active TGF-β1 induces synergistic pulmonary fibroproliferation in vivo

2012 ◽  
Vol 303 (9) ◽  
pp. L788-L798 ◽  
Author(s):  
Graciela Andonegui ◽  
Ai Ni ◽  
Caroline Léger ◽  
Margaret M. Kelly ◽  
Josée F. Wong ◽  
...  

Pulmonary fibrosis, the end stage of a variety of fibroproliferative lung diseases, is usually induced after repetitive or chronic lung injury or inflammation. The mechanisms of fibroproliferation are poorly understood. Insulin-like growth factor-I (IGF-I) is significantly elevated in patients with pulmonary fibrosis and fibroproliferative acute respiratory distress syndrome. However, we showed that IGF-I overexpression alone in wild-type mouse lungs does not cause fibroproliferation. We therefore questioned whether IGF-I, acting together with active TGF-β1, a known profibrotic cytokine, enhances pulmonary fibroproliferation caused by active TGF-β1. A unique sequential adenoviral transgene mouse model was used expressing AdEmpty/AdTGF-β1 or AdhIGF-IB/AdTGF-β1 transgenes. IGF-IB plus active TGF-β1 transgene expression synergistically increased collagen deposition in the lung parenchyma compared with active TGF-β1 expression alone. The enhanced fibrosis was accompanied by an increased recruitment of macrophages and lymphocytes into the bronchoalveolar lavage fluid (BALF) and inflammatory cells in the lungs. α-Smooth muscle actin expression, a marker of myofibroblast proliferation and differentiation, was also increased. Finally, fibroblasts exposed ex vivo to BALF isolated from AdhIGF-IB/AdTGF-β1-transduced mice showed synergistic collagen induction compared with BALF from AdEmpty/AdTGF-β1-transduced mice. This study provides the first direct evidence that IGF-I is able to synergistically enhance pulmonary fibroproliferation in cooperation with TGF-β1.

2021 ◽  
Author(s):  
Andrea Grandi ◽  
Erica Ferrini ◽  
Roberta Ciccimarra ◽  
Martina Mambrini ◽  
Laura Mecozzi ◽  
...  

Abstract Background.Idiopathic Pulmonary Fibrosis is a progressive disease with short life expectancy and no disease-modifying pharmacological therapy. The continuous refinement of animal models and the integration of in-vivo imaging techniques is fundamental for the selection of new antifibrotic drugs.Indocyanine Green (ICG), a fluorescent dye, was administered by oropharyngeal aspiration (OA) to mice with Bleomycin (BLM) to map the lung exposure.Methods.Female mice C57bl/6 were treated via OA with BLM+ICG or ICG. Animals were imaged at 7, 14 and 21 days either with the fluorescent system or Micro-CT. At each time point subsets of mice were sampled for ex-vivo assessment. Histological assessment of fibrosis by Ashcroft score, airspace enlargements and mean linear intercept (MLI) were evaluated at 7, 14 and 21 days. Leukocytes and cytokines were measured in bronchoalveolar lavage fluid. Results.Fluorescence imaging revealed a persistent lung signal in both groups until 21 days. In BLM+ICG group, Micro-CT detected a marked increase in hypo- and non-aerated tissues throughout the study. At later time points hyper-inflated tissue was detected. Histology revealed high Ashcroft score throughout the time-course with a prominent increase in airspace size and MLI at day 21. ICG mice had healthy lungs.Conclusions.We showed that ICG can be used as a tracer to map the distribution of BLM in lungs. However, BLM+ICG produced unexpected severe lung changes different from pure BLM model, such as emphysema-like features which progressively worsened. The multimodalities approach warranted characterization of the distinctive features of this new pulmonary fibrosis model and provided fundamentals for in-vivo translation.


Author(s):  
Yuanyuan Liu ◽  
Wenshan Zhong ◽  
Jinming Zhang ◽  
Weimou Chen ◽  
Ye Lu ◽  
...  

Background and Purpose Idiopathic pulmonary fibrosis is a progressive fatal disease characterized by interstitial remodeling, with high lethality and a lack of effective medical therapies. Tetrandrine has been proposed to present anti-fibrotic effects, but the efficacy and mechanisms of tetrandrine against lung fibrosis has not been systematically evaluated. We sought to study the potential therapeutic effects and mechanisms of tetrandrine in lung fibrosis. Experimental Approach The anti-fibrotic effects of tetrandrine were evaluated in bleomycin-induced mouse models and TGF-β1-stimulated murine lung fibroblasts. We performed Chromatin Immunoprecipitation (ChIP), Immunoprecipitation (IP) and mRFP-GFP-MAP1LC3B adenovirus construct to investigate the novel mechanisms of tetrandrine-induced autophagy. Key Results Tetrandrine decreased TGF-β1-induced expression of α-smooth muscle actin, fibronectin, vimentin and type 1 collagen and proliferation in fibroblasts. Tetrandrine restored TGF-β1-induced impaired autophagy, accompanied by the up-regulation and enhanced interaction of SQSTM1 and MAP1LC3-Ⅱ. ChIP studies revealed that NRF2 bound to SQSTM1 promoter in tetrandrine-induced autophagy. Furthermore, TGF-β1-induced phosphorylated mTOR was inhibited by tetrandrine, with reduced activation levels of Rheb. In vivo tetrandrine suppressed the bleomycin-induced expression of fibrotic markers and improved pulmonary function. Conclusion and Implications Our data suggest that tetrandrine might be recognized as a novel autophagy inducer, thus attenuating lung fibrosis. Tetrandrine should be investigated as a novel therapeutic strategy for IPF.


Author(s):  
Hyo Jae Kang ◽  
Kyung Jin Lee ◽  
Jisu Woo ◽  
Jiyeon Kim ◽  
Yun Kyu Kim ◽  
...  

AbstractPulmonary fibrosis is a progressive and lethal lung disease characterized by the proliferation and differentiation of lung fibroblasts and the accumulation of extracellular matrices. Since pulmonary fibrosis was reported to be associated with adenosine monophosphate-activated protein kinase (AMPK) activation, which is negatively regulated by cereblon (CRBN), we aimed to determine whether CRBN is involved in the development of pulmonary fibrosis. Therefore, we evaluated the role of CRBN in bleomycin (BLM)-induced pulmonary fibrosis in mice and in transforming growth factor-beta 1 (TGF-β1)-induced differentiation of human lung fibroblasts. BLM-induced fibrosis and the mRNA expression of collagen and fibronectin were increased in the lung tissues of wild-type (WT) mice; however, they were significantly suppressed in Crbn knockout (KO) mice. While the concentrations of TGF-β1/2 in bronchoalveolar lavage fluid were increased via BLM treatment, they were similar between BLM-treated WT and Crbn KO mice. Knockdown of CRBN suppressed TGF-β1-induced activation of small mothers against decapentaplegic 3 (SMAD3), and overexpression of CRBN increased it. TGF-β1-induced activation of SMAD3 increased α-smooth muscle actin (α-SMA) and collagen levels. CRBN was found to be colocalized with AMPKα1 in lung fibroblasts. CRBN overexpression inactivated AMPKα1. When cells were treated with metformin (an AMPK activator), the CRBN-induced activation of SMAD3 and upregulation of α-SMA and collagen expression were significantly suppressed, suggesting that increased TGF-β1-induced activation of SMAD3 via CRBN overexpression is associated with AMPKα1 inactivation. Taken together, these data suggest that CRBN is a profibrotic regulator and maybe a potential target for treating lung fibrosis.


2014 ◽  
Vol 306 (4) ◽  
pp. L326-L340 ◽  
Author(s):  
Shilpa Vyas-Read ◽  
Wenyi Wang ◽  
Satomi Kato ◽  
Jennifer Colvocoresses-Dodds ◽  
Nimita H. Fifadara ◽  
...  

Myofibroblast accumulation is a pathological feature of lung diseases requiring oxygen therapy. One possible source for myofibroblasts is through the epithelial-to-mesenchymal transition (EMT) of alveolar epithelial cells (AEC). To study the effects of oxygen on alveolar EMT, we used RLE-6TN and ex vivo lung slices and found that hyperoxia (85% O2, H85) decreased epithelial proteins, presurfactant protein B (pre-SpB), pro-SpC, and lamellar protein by 50% and increased myofibroblast proteins, α-smooth muscle actin (α-SMA), and vimentin by over 200% ( P < 0.05). In AEC freshly isolated from H85-treated rats, mRNA for pre-SpB and pro-SpC was diminished by ∼50% and α-SMA was increased by 100% ( P < 0.05). Additionally, H85 increased H2O2 content, and H2O2 (25–50 μM) activated endogenous transforming growth factor-β1 (TGF-β1), as evident by H2DCFDA immunofluorescence and ELISA ( P < 0.05). Both hyperoxia and H2O2 increased SMAD3 phosphorylation (260% of control, P < 0.05). Treating cultured cells with TGF-β1 inhibitors did not prevent H85-induced H2O2 production but did prevent H85-mediated α-SMA increases and E-cadherin downregulation. Finally, to determine the role of TGF-β1 in hyperoxia-induced EMT in vivo, we evaluated AEC from H85-treated rats and found that vimentin increased ∼10-fold ( P < 0.05) and that this effect was prevented by intraperitoneal TGF-β1 inhibitor SB-431542. Additionally, SB-431542 treatment attenuated changes in alveolar histology caused by hyperoxia. Our studies indicate that hyperoxia promotes alveolar EMT through a mechanism that is dependent on activation of TGF-β1 signaling.


2021 ◽  
Vol 12 ◽  
Author(s):  
Yuanyuan Liu ◽  
Wenshan Zhong ◽  
Jinming Zhang ◽  
Weimou Chen ◽  
Ye lu ◽  
...  

Idiopathic pulmonary fibrosis is a progressive fatal disease characterized by interstitial remodeling, with high lethality and a lack of effective medical therapies. Tetrandrine has been proposed to present anti-fibrotic effects, but the efficacy and mechanisms have not been systematically evaluated. We sought to study the potential therapeutic effects and mechanisms of tetrandrine against lung fibrosis. The anti-fibrotic effects of tetrandrine were evaluated in bleomycin-induced mouse models and TGF-β1-stimulated murine lung fibroblasts. We performed Chromatin Immunoprecipitation (ChIP), Immunoprecipitation (IP), and mRFP-GFP-MAP1LC3B adenovirus construct to investigate the novel mechanisms of tetrandrine-induced autophagy. Tetrandrine decreased TGF-β1-induced expression of α-smooth muscle actin, fibronectin, vimentin, and type 1 collagen and proliferation in fibroblasts. Tetrandrine restored TGF-β1-induced impaired autophagy flux, accompanied by enhanced interaction of SQSTM1 and MAP1LC3-Ⅱ. ChIP studies revealed that tetrandrine induced autophagy via increasing binding of NRF2 and SQSTM1 promoter. Furthermore, tetrandrine inhibited TGF-β1-induced phosphorylation of mTOR by reducing activation of Rheb. In vivo tetrandrine suppressed the bleomycin-induced expression of fibrotic markers and improved pulmonary function. Our data suggest that protective effect of tetrandrine against lung fibrosis might be through promoting Rheb-mTOR and NRF2-SQSTM1 mediated autophagy. Tetrandrine may thus be potentially employed as a novel therapeutic medicine against IPF.


2020 ◽  
Vol 21 (20) ◽  
pp. 7761
Author(s):  
Roberta Fusco ◽  
Rosalba Siracusa ◽  
Ramona D’Amico ◽  
Marika Cordaro ◽  
Tiziana Genovese ◽  
...  

Pulmonary fibrosis is a progressive disease characterized by lung remodeling due to excessive deposition of extracellular matrix. In this study, the bleomycin experimental model of pulmonary fibrosis was employed to investigate the anti-fibrotic and immunomodulatory activity of the inhibition of MALT1 protease activity. Mice received a single intra-tracheal administration of bleomycin (1 mg/kg) in the presence or absence of MI-2, a selective MALT1 inhibitor, (a dose of 30 mg/kg administered intra-peritoneally 1 h after bleomycin and daily until the end of the experiment). Seven days after bleomycin instillation mice were sacrificed and bronchoalveolar lavage fluid analysis, measurement of collagen content in the lung, histology, molecular analysis and immunohistochemistry were performed. To evaluate mortality and body weight gain a subset of mice was administered daily with MI-2 for 21 days. Mice that received MI-2 showed decreased weight loss and mortality, inflammatory cells infiltration, cytokines overexpression and tissue injury. Moreover, biochemical and immunohistochemical analysis displayed that MI-2 was able to modulate the excessive production of reactive oxygen species and the inflammatory mediator upregulation induced by bleomycin instillation. Additionally, MI-2 demonstrated anti-fibrotic activity by reducing transforming growth factor-β (TGF-β), α-smooth muscle actin (α-SMA) and receptor associated factor 6 (TRAF6) expression. The underlying mechanisms for the protective effect of MI-2 bleomycin induced pulmonary fibrosis may be attributed to its inhibition on NF-κB pathway. This is the first report showing the therapeutic role of MALT1 inhibition in a bleomycin model of pulmonary fibrosis, thus supporting further preclinical and clinical studies.


2021 ◽  
Vol 22 (4) ◽  
pp. 1985
Author(s):  
Xiaohe Li ◽  
Ling Ma ◽  
Kai Huang ◽  
Yuli Wei ◽  
Shida Long ◽  
...  

Idiopathic pulmonary fibrosis (IPF) is a fatal and age-related pulmonary disease. Nintedanib is a receptor tyrosine kinase inhibitor, and one of the only two listed drugs against IPF. Regorafenib is a novel, orally active, multi-kinase inhibitor that has similar targets to nintedanib and is applied to treat colorectal cancer and gastrointestinal stromal tumors in patients. In this study, we first identified that regorafenib could alleviate bleomycin-induced pulmonary fibrosis in mice. The in vivo experiments indicated that regorafenib suppresses collagen accumulation and myofibroblast activation. Further in vitro mechanism studies showed that regorafenib inhibits the activation and migration of myofibroblasts and extracellular matrix production, mainly through suppressing the transforming growth factor (TGF)-β1/Smad and non-Smad signaling pathways. In vitro studies have also indicated that regorafenib could augment autophagy in myofibroblasts by suppressing TGF-β1/mTOR (mechanistic target of rapamycin) signaling, and could promote apoptosis in myofibroblasts. In conclusion, regorafenib attenuates bleomycin-induced pulmonary fibrosis by suppressing the TGF-β1 signaling pathway.


Open Medicine ◽  
2020 ◽  
Vol 15 (1) ◽  
pp. 1202-1212
Author(s):  
Aichun Zhang ◽  
Yangzi Jin

AbstractAllergic rhinitis (AR) is one of the most common chronic diseases. This study examined whether microRNA (miR)-182-5p plays a role in AR by regulating toll-like receptor 4 (TLR4). First, data demonstrated that TLR4 was a target of miR-182-5p. Subsequently, AR mouse model was established to explore the role of miR-182-5p and TLR4 in AR in vivo. Initially, quantitative reverse transcription-PCR (qRT-PCR) analysis indicated that miR-182-5p was downregulated, while TLR4 expression was upregulated in AR mice. Then we found that miR-182-5p mimic reduced the frequency of sneezing and nose rubbing of the AR mice. In addition, miR-182-5p mimic significantly increased ovalbumin (OVA)-specific IgE and leukotriene C4 expression levels in nasal lavage fluid (NLF) and serum of AR mice. miR-182-5p mimic decreased the number of inflammatory cells in NLF of AR mice. It also reduced the levels of inflammatory factors in the serum of AR mice, such as interleukin (IL)-4, IL-5, IL-13, IL-17 and tumor necrosis factor (TNF)-α, while increasing the release of IFN-γ and IL-2. Finally, miR-182-5p mimic inhibited NF-κB signaling pathway activation in AR mice. However, all effects of miR-182-5p mimic on AR mice were reversed by TLR4-plasmid. In conclusion, miR-182-5p/TLR4 axis may represent a novel therapeutic target for AR.


2017 ◽  
Vol 23 (7) ◽  
pp. 615-624 ◽  
Author(s):  
Huimin Yue ◽  
Yarong Zhao ◽  
Haining Wang ◽  
Feiya Ma ◽  
Fei Liu ◽  
...  

Hirsutella sinensis, cultured in vitro, is an attractive substitute for Cordyceps sinensis as health supplement. The aim of this study was to demonstrate whether H. sinensis mycelium (HSM) attenuates murine pulmonary fibrosis induced by bleomycin and to explore the underlying molecular mechanisms. Using lung fibrosis modle induced by intratracheal instillation of bleomycin (BLM; 4 mg/kg), we observed that the administration of HSM reduced HYP, TGF-β1 and the production of several pro-fibrosis cytokines (α-smooth muscle actin, fibronectin and vimentin) in fibrotic mice lung sections. Histopathological examination of lung tissues also demonstrated that HSM improved BLM-induced pathological damage. Concurrently, HSM supplementation markedly reduced the chemotaxis of alveolar macrophages and potently suppressed the expression of inflammatory cytokines. Also, HSM influenced Th1/Th2 and Th17/Treg imbalance and blocked the phosphorylation of mTOR pathway in vivo. Alveolar epithelial A549 cells acquired a mesenchymal phenotype and an increased expression of myofibroblast markers of differentiation (vimentin and fibronectin) after treatment with TGF-β1. HSM suppressed these markers and blocked the phosphorylation of mTOR pathway in vitro. The results provide evidence supporting the use of HSM in the intervention of pulmonary fibrosis and suggest that HSM is a potential therapeutic agent for lung fibrosis.


1994 ◽  
Vol 266 (6) ◽  
pp. L593-L611 ◽  
Author(s):  
M. D. Evans ◽  
W. A. Pryor

The proteinase-antiproteinase theory for the pathogenesis of emphysema proposes that the connective tissue destruction associated with emphysema arises from excessive proteinase activity in the lower respiratory tract. For this reason, the relative activities of neutrophil elastase and alpha 1-proteinase inhibitor (alpha 1-PI) are considered important. Most emphysema is observed in smokers; therefore, alpha 1-PI has been studied as a target for smoke-induced damage. Damage to alpha 1-PI in lung fluid could occur by several mechanisms involving species delivered to the lung by cigarette smoke and/or stimulated inflammatory cells. Oxidative damage to alpha 1-PI has received particular attention, since both cigarette smoke and inflammatory cells are rich sources of oxidants. In this article we review almost two decades of research on mechanistic studies of damage to alpha 1-PI by cigarette smoke and phagocytic cells in vitro, studies emphasizing the importance of elastinolytic activity in the pathogenesis of emphysema in vivo and studies of human lung lavage fluid to detect defects in alpha 1-PI at the molecular and functional levels.


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