Rat Model Of Pulmonary Fibrosis Research Articles

Sinomenine attenuates bleomycin-induced pulmonary fibrosis, inflammation, and oxidative stress by inhibiting TLR4/NLRP3/TGFβ signaling

Objective The present work concentrated on validating whether sinomenine alleviates bleomycin (BLM)-induced pulmonary fibrosis, inflammation, and oxidative stress. Methods A rat model of pulmonary fibrosis was constructed through intratracheal injection with 5 mg/kg BLM, and the effects of 30 mg/kg sinomenine on pulmonary inflammation, fibrosis, apoptosis, and 4-hydroxynonenal density were evaluated by hematoxylin and eosin staining, Masson’s trichrome staining, TUNEL staining, and immunohistochemistry. Hydroxyproline content and concentrations of inflammatory cytokines and oxidative stress markers were detected using corresponding kits. MRC-5 cells were treated with 10 ng/ml PDGF, and the effects of 1 mM sinomenine on cell proliferation were assessed by EdU assays. The mRNA expression of inflammatory cytokines and the protein levels of collagens, fibrosis markers, and key markers involved in the TLR4/NLRP3/TGFβ signaling were tested with RT-qPCR and immunoblotting analysis. Results Sinomenine attenuated pulmonary fibrosis and inflammation while reducing hydroxyproline content and the protein expression of collagens and fibrosis markers in BLM-induced pulmonary fibrosis rats. Sinomenine reduced apoptosis in lung samples of BLM-challenged rats by increasing Bcl-2 and reducing Bax and cleaved caspase-3 protein expression. In addition, sinomenine alleviated inflammatory response and oxidative stress in rats with pulmonary fibrosis induced by BLM. Moreover, sinomenine inhibited the TLR4/NLRP3/TGFβ signaling pathway in lung tissues of BLM-stimulated rats. Furthermore, TLR4 inhibitor, TAK-242, attenuated PDGF-induced fibroblast proliferation and collagen synthesis in MRC-5 cells. Conclusion Sinomenine attenuates BLM-caused pulmonary fibrosis, inflammation, and oxidative stress by inhibiting the TLR4/NLRP3/TGFβ signaling, indicating that sinomenine might become a therapeutic candidate to treat pulmonary fibrosis.

Protective Effects of Tunisian Orange Co-Product Extract and Oleuropein-Hesperidin Combination on Bleomycin-Induced Pulmonary Fibrosis in Rats.

Idiopathic pulmonary fibrosis (IPF) is a chronic interstitial pneumonia with acute lung damage leading to the deterioration of lung function and increased mortality risk. In this study, we aimed to investigate the effects of the orange coproduct extract (OCE) and the combination of pure hesperidin and oleuropein (HO) on an experimental model of pulmonary fibrosis induced by bleomycin (BLM). Wistar rats were divided into 6 groups: the control group (G1), the BLM group (G2), 3 groups (G3, G4, G5) receiving a single dose of BLM combined with OCE extract at 100, 200 and 300 mg/kg and group 6 (G6) receiving a single dose of BLM combined with HO: both pure major phenolic compounds of OCE (hesperidin at 50 mg/kg) and olive leaves (oleuropein at 2.5 mg/kg). Oxidative stress in lung tissues was investigated using catalase (CAT), superoxide dismutase (SOD) and glutathione peroxidase (GPX) assays and the measurement of malondialdehyde (MDA) and lactate dehydrogenase (LDH) levels. Treatment with OCE and HO were able to normalize the disturbance in oxidative markers' levels and showed a significant reduction in fibrosis score with no renal or hepatic toxic effects. In conclusion, OCE and HO exhibit antifibrotic effects on rat model of pulmonary fibrosis.

Study on miRNA expression and regulatory network of Amygdalus mongolica oil and amygdalin in the treatment of pulmonary fibrosis

IntroductionAmygdalus mongolica (Maxim.) Ricker is a traditional Chinese medicine known for its ability to relieve cough and expectorate phlegm and is commonly used to treat dry throat, dry cough, and bronchitis. A. mongolica oil and amygdalin were the active components isolated from the seed kernel seeds of A. mongolica. The main objective of this study was to investigate the effects of A. mongolica oil and amygdalin on bleomycin-induced pulmonary fibrosis (PF) in rats by integrating pharmacodynamic, transcriptomics, and bioinformatics, to determine the changes of miRNAs in both against PF, and to explore the underlying mechanisms. MethodsA rat model of PF was induced by administering bleomycin through the trachea. The rats were randomized into several groups: a control group (CON), an untreated model group (MOD), an active control group treated with pirfenidone (PFD), and groups receiving different doses of A. mongolica oil (5 g/kg [OIL-L], 10 g/kg [OIL-M], and 15 g/kg [OIL-H]), or amygdalin (20 mg/kg [AMY-L], 40 mg/kg [AMY-M], and 80 mg/kg [AMY-H]). After 28 days, samples were collected for subsequent pharmacodynamic and transcriptomic analyses. ResultsThe results demonstrated that A. mongolica oil and amygdalin effectively reduced the abnormally elevated levels of IL-1β, IL-6, HA, LN and COL-IV in PF rats and alleviated bleomycin-induced pulmonary fibrotic changes. Furthermore, compared to the MOD group, the expression levels of 27 miRNAs were up-regulated and 23 miRNAs were down-regulated in the OIL 10 g/kg group. Among the up-regulated miRNAs, two novel differentially expressed miRNAs (DE-miRNAs) were identified. In the AMY 20 mg/kg group, 12 miRNAs were up-regulated and 10 were down-regulated when compared to the MOD group. These DE-miRNAs were found to be enriched in pathways such as the PI3K-Akt signalling pathway, MAPK signalling pathway, and calcium signalling pathway. The microRNAs miR-301b-3p, miR-667-5p, miR-363-3p, and miR-540-3p may be associated with both the anti-PF mechanism of A. mongolica oil and the anti-PF mechanism of amygdalin. DiscussionNumerous studies have demonstrated the significance of various pathways, including PI3K-Akt, MAPK, and calcium signalling pathways, in the mechanism of PF and the development of anti-PF medications. Meanwhile, multiple miRNAs, including miR-301b-3p, miR-667-5p, miR-363-3p, and miR-540-3p, have been found to be associated with lung disease and fibrosis. ConclusionsThe present experiments confirmed the effectiveness of A. mongolica oil and amygdalin in reducing inflammation and fibrosis in bleomycin-induced PF rats, with particularly favorable outcomes observed in the A. mongolica oil 10 g/kg versus amygdalin 20 mg/kg. Meanwhile, miRNAs miR-301b-3p, miR-667-5p, miR-363-3p and miR-540-3p were found to be potentially associated with both A. mongolica oil and amygdalin anti-PF mechanisms. Based on our findings, we suggest that these miRNAs might play key roles in the anti-PF mechanism of A. mongolica. The individual miRNAs require further investigation.

Assessment of progression of pulmonary fibrosis based on metabonomics and analysis of intestinal microbiota

The main purpose of this study was to explore the changes of biomarkers in different developmental stages of bleomycin-induced pulmonary fibrosis (PF) in rats via comprehensive pathophysiology, UPLC-QTOF/MS metabonomic technology, and 16S rRNA gene sequencing of intestinal microbiota. The rats were randomly divided into normal control and 1-, 2- and 4-week model group. The rat model of PF was established by one-time intratracheal instillation of bleomycin. The levels of inflammatory and fibrosis-related factors such as hydroxyproline (HYP), type III procollagen (COL-III), type IV collagen (COL-IV), hyaluronidase (HA), laminin (LN), interleukin (IL)-1β, IL-6, malondialdehyde (MDA) increased and superoxide dismutase (SOD) decreased as the PF cycle progressed. In the 1-, 2- and 4-week model group, 2, 19 and 18 potential metabolic biomarkers and 3, 16 and 12 potential microbial biomarkers were detected, respectively, which were significantly correlated. Glycerophospholipid metabolism pathway was observed to be an important pathway affecting PF at 1, 2 and 4 weeks; arginine and proline metabolism pathways significantly affected PF at 2 weeks. Linoleic acid metabolism pathway exhibited clear metabolic abnormalities at 2 and 4 weeks of PF, and alpha-linolenic acid metabolism pathway significantly affected PF at 4 weeks.

Insights into Disease Progression of Translational Preclinical Rat Model of Interstitial Pulmonary Fibrosis through Endpoint Analysis.

Idiopathic pulmonary fibrosis (IPF) is a devastating interstitial lung disease characterized by the relentless deposition of extracellular matrix (ECM), causing lung distortions and dysfunction. Animal models of human IPF can provide great insight into the mechanistic pathways underlying disease progression and a means for evaluating novel therapeutic approaches. In this study, we describe the effect of bleomycin concentration on disease progression in the classical rat bleomycin model. In a dose-response study (1.5, 2, 2.5 U/kg i.t), we characterized lung fibrosis at day 14 after bleomycin challenge using endpoints including clinical signs, inflammatory cell infiltration, collagen content, and bronchoalveolar lavage fluid-soluble profibrotic mediators. Furthermore, we investigated fibrotic disease progression after 2 U/kg i.t. bleomycin administration at days 3, 7, and 14 by quantifying the expression of clinically relevant signaling molecules and pathways, epithelial mesenchymal transition (EMT) biomarkers, ECM components, and histopathology of the lung. A single bleomycin challenge resulted in a progressive fibrotic response in rat lung tissue over 14 days based on lung collagen content, histopathological changes, and modified Ashcroft score. The early fibrogenesis phase (days 3 to 7) is associated with an increase in profibrotic mediators including TGFβ1, IL6, TNFα, IL1β, CINC1, WISP1, VEGF, and TIMP1. In the mid and late fibrotic stages, the TGFβ/Smad and PDGF/AKT signaling pathways are involved, and clinically relevant proteins targeting galectin-3, LPA1, transglutaminase-2, and lysyl oxidase 2 are upregulated on days 7 and 14. Between days 7 and 14, the expressions of vimentin and α-SMA proteins increase, which is a sign of EMT activation. We confirmed ECM formation by increased expressions of procollagen-1Aα, procollagen-3Aα, fibronectin, and CTGF in the lung on days 7 and 14. Our data provide insights on a complex network of several soluble mediators, clinically relevant signaling pathways, and target proteins that contribute to drive the progressive fibrotic phenotype from the early to late phase (active) in the rat bleomycin model. The framework of endpoints of our study highlights the translational value for pharmacological interventions and mechanistic studies using this model.

Modified Qing-Zao-Jiu-Fei decoction attenuated pulmonary fibrosis induced by bleomycin in rats via modulating Nrf2/NF-κB and MAPKs pathways

BackgroundQing-Zao-Jiu-Fei Decoction (QZJFD) is a famous herbal formula commonly prescribed for the treatment of lung-related diseases in the ancient and modern times. Trichosanthis Fructus (TF) and Fritillariae Thunbergii Bulbus (FTB) are widely used for treatment of cough and pulmonary disease. In order to identify a more effective formula for treatment of pulmonary fibrosis, we intend to add TF and FTB in QZJFD to form a modified QZJFD (MQZJFD). In this study, we aims to explore MQZJFD as an innovative therapeutic agent for pulmonary fibrosis using bleomycin (BLM)-treated rats and to unravel the underlying molecular mechanisms.MethodsBLM was given to SD rats by intra-tracheal administration of a single dose of BLM (5 mg/kg). QZJFD (3 g/kg) and MQZJFD (1, 2 and 4 g/kg) was given intragastrically daily to rats for 14 days (from day 15 to 28) after BLM administration for 14 consecutive days.ResultsMQZJFD was found to contain 0.29% of amygdalin, 0.020% of lutin, 0.077% of glycyrrhizic acid and 0.047% of chlorogenic acid. BLM treatment could induce collagen deposition in the lung tissues of rats, indicating that the pulmonary fibrosis rat model had been successfully established. MQZJFD have better effects than the original QZJFD in reducing the pulmonary structure damage and collagen deposition of rat lung fibrosis induced by BLM. MQZJFD could reduce the hydroxyproline content in lung tissues of BLM-treated rats. The biomarkers of fibrosis such as matrix metalloproteinase 9 (MMP9), collagen I and α-smooth muscle actin (α-SMA) were remarkably reduced after treatment with MQZJFD. MQZJFD also have anti-oxidant stress effects by inhibiting the level of malondialdehyde (MDA), but enhancing the activities of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px), and the level of glutathione (GSH) in the lung tissues of BLM-treated rats. Moreover, the MQZJFD markedly suppressed the over expressions of p-p65/p65 and p-IκBα/IκBα, but upregulated the Nrf2. MQZJFD also suppressed the protein expressions of p-ERK1/2/ERK1/2, p-p38/p38 and p-JNK/JNK in the lung tissues of BLM-treated rats.ConclusionsMQZJFD could improve the pulmonary fibrosis induced by BLM in rats via inhibiting the fibrosis and oxidative stress via suppressing the activation of NF-κB/Nrf2 and MAPKs pathways.

Total alkaloids of bulbus of Fritillaria cirrhosa alleviate bleomycin-induced inflammation and pulmonary fibrosis in rats by inhibiting TGF-β and NF-κB signaling pathway.

Bulbus of Fritillaria cirrhosa is a medicinal and edible plant that has the functions of clearing away heat and moisturizing the lungs, resolving phlegm, and relieving coughs. Its ethanol extract has been proven to have a therapeutic effect on lung diseases. Pulmonary fibrosis is a respiratory disease that forms scars in lung tissue, leading to severe respiratory problems. However, the therapeutic effect of total alkaloids of bulbus of Fritillaria cirrhosa (BFC-TA) on pulmonary fibrosis has not been confirmed. This study aimed to investigate the therapeutic effect of total alkaloids of Fritillaria cirrhosa on pulmonary fibrosis rat model and explore its potential mechanism. The total alkaloids in the bulbus of Fritillaria cirrhosa were purified using cation exchange resin. The alkaloids contained in the BFC-TA were identified, and the concentration of alkaloids was determined by High Performance Liquid Chromatography-Diode Array Detector-Evaporative Light Scattering Detector (HPLC-DAD-ELSD). Bleomycin (BLM) (5.0 mg/kg) was instilled into the trachea of 60 rats to establish a pulmonary fibrosis model. After 7 days, BFC-TA (34.2, 68.4, and 136.8 mg/kg) was administered continuously for 21 days. During this period, the body weight changes of the rats were measured, the levels of hydroxyproline (HYP) and inflammatory factors were measured in the collected serum, and the histological analysis of the lung tissue was performed by staining technology. Western blotting and quantitative Polymerase Chain Reaction (qPCR) were used to assess the protein and gene composition of inflammation and transforming growth factor-β (TGF-β) signaling pathways. Nine main components (Peimisine, Imperialine-3-β-D-glucoside, Yibeinoside A, Imperialine, Peiminine, Isopeimine, Hupehenine, Delavinone, Ebeiedinone) were determined by HPLC-DAD-ELSD, and the contents of Peimisine, Imperialine-3-β-D-glucoside and Imperialine were determined. BFC-TA (34.2, 68.4, and 136.8 mg/kg) reduced the levels of pro-inflammatory factors, increased the levels of anti-inflammatory factors, dose-dependently improved the morphology of lung tissue. And during epithelial-mesenchymal transition process, BFC-TA dose-dependently reduced the expression of E-cadherin, dose-dependently increased the expression of Fibronectin. In addition, Western blot analysis and qPCR results showed that inhibiting NF-κB and TGF-β-related signaling pathways effectively slowed down the occurrence of BLM-induced pulmonary fibrosis in rats. And the therapeutic effect of BFC-TA (136.8 mg/kg) is better than that of pirfenidon (PFD) (150 mg/kg). BFC-TA effectively alleviates the progression of the BLM-induced pulmonary fibrosis rat model by regulating the inflammatory response in the lungs and the expression of the TGF-β signaling pathway.

Regulation of miRNA-155-5p ameliorates NETosis in pulmonary fibrosis rat model via inhibiting its target cytokines IL-1β, TNF-α and TGF-β1

Idiopathic pulmonary fibrosis (IPF) is an age-related inflammatory disease with no cure up till now.It is accompanied by neutrophils infiltration as the main responders to inflammation and fibrosis. Importantly, neutrophils release neutrophil extracellular traps (NETs) through NETosis process. The function of microRNAs during inflammation became of great biological attention. Owing to microRNAs’ central role in immune system, microRNA-155-5p (miR-155-5p) is intensely involved in the inflammatory response. Capsaicin (Cap) is a bioactive compound that exhibits antioxidative and anti-inflammatory functions. Recent studies have shown its role in regulation of certain microRNAs’ expressions. Accordingly, the present study aims to investigate the effect of miR-155-5p regulation in suppressing NETs production via ameliorating its target inflammatory cytokines, IL-1ß, TNF-α and TGF-ß1, in bleomycin (BLM)-induced pulmonary fibrosis rat model treated by Cap. The obtained results demonstrated that miR-155-5p downregulation was associated with significant decrease in IL-1ß, TNF-α, TGF-β1, which consequently, reduced hydroxyproline (HYP), NETs activity markers as NE and PAD-4, and alleviated CTGF levels in lung tissues of animals treated by Cap. Furthermore, NETosis ultrastructure examination by transmission electron microscope (TEM), MPO immunohistochemical staining and histopathological studies confirmed an abolishment in NETs formation and an improvement in lung tissue architecture in Cap-treated rats. This study concluded that Cap quenched the inflammatory response through interrupting IL-1β, TNF-α and TGF-β1 pathway via modulating miR-155-5p expression. In addition, Cap was able to alleviate pulmonary NETosis markers by restraining NETs activity markers. These findings provide novel insight into the application of Cap-based treatment in ameliorating pulmonary damage in IPF.

Quercetin influences intestinal dysbacteriosis and delays alveolar epithelial cell senescence by regulating PTEN/PI3K/AKT signaling in pulmonary fibrosis.

Pulmonary fibrosis is a chronic and progressive lung disease with high mortality. This study aims to explore the protective mechanism of quercetin against pulmonary fibrosis regarding cell senescence and gut microbiota. Rats were intratracheally injected with bleomycin (BLM) to establish a pulmonary fibrosis rat model. RLE-6TN cells were stimulated with BLM to build the model of alveolar epithelial cell senescence, and RLE-6TN-derived conditional medium (CM) was harvested to further culture fibroblasts. Histopathological changes were assessed by H&E and Masson staining. α-SMA expression was assessed by immunofluorescence assay. Senescence-associated β-galactosidase (SA-β-gal) staining and senescence-associated secretory phenotype (SASP) cytokine assay were conducted to assess cellular senescence. Gut microbiota was analyzed by 16S rRNA gene sequencing. The fibrosis-, senescence-, and PTEN/PI3K/AKT signaling-related proteins were examined by western blot. In BLM-induced pulmonary fibrosis rats, quercetin exerted its protective effects by reducing histological injury and collagen deposition, lessening cellular senescence, and regulating gut microbiota. In BLM-induced alveolar epithelial cell senescence, quercetin inhibited senescence, lessened SASP cytokine secretion of alveolar epithelial cells, and further ameliorated collagen deposition in fibroblasts. In addition, quercetin might exert its functional effects by regulating the PTEN/PI3K/AKT signaling pathway. Moreover, quercetin regulated intestinal dysbacteriosis in BLM-induced pulmonary fibrosis rats, especially boosting the abundance of Akkermansia. To conclude, our findings provide an in-depth understanding of the potential mechanism behind the protective role of quercetin against pulmonary fibrosis.

Alvespimycin Exhibits Potential Anti-TGF-β Signaling in the Setting of a Proteasome Activator in Rats with Bleomycin-Induced Pulmonary Fibrosis: A Promising Novel Approach.

Idiopathic pulmonary fibrosis (IPF) is an irreversible and life-threatening lung disease of unknown etiology presenting only a few treatment options. TGF-β signaling orchestrates a cascade of events driving pulmonary fibrosis (PF). Notably, recent research has affirmed the augmentation of TGF-β receptor (TβR) signaling via HSP90 activation. HSP90, a molecular chaperone, adeptly stabilizes and folds TβRs, thus intricately regulating TGF-β1 signaling. Our investigation illuminated the impact of alvespimycin, an HSP90 inhibitor, on TGF-β-mediated transcriptional responses by inducing destabilization of TβRs. This outcome stems from the explicit interaction of TβR subtypes I and II with HSP90, where they are clients of this cellular chaperone. It is worth noting that regulation of proteasome-dependent degradation of TβRs is a critical standpoint in the termination of TGF-β signal transduction. Oleuropein, the principal bioactive compound found in Olea europaea, is acknowledged for its role as a proteasome activator. In this study, our aim was to explore the efficacy of a combined therapy involving oleuropein and alvespimycin for the treatment of PF. We employed a PF rat model that was induced by intratracheal bleomycin infusion. The application of this dual therapy yielded a noteworthy impediment to the undesired activation of TGF-β/mothers against decapentaplegic homologs 2 and 3 (SMAD2/3) signaling. Consequently, this novel combination showcased improvements in both lung tissue structure and function while also effectively restraining key fibrosis markers such as PDGF-BB, TIMP-1, ACTA2, col1a1, and hydroxyproline. On a mechanistic level, our findings unveiled that the antifibrotic impact of this combination therapy likely stemmed from the enhanced degradation of both TβRI and TβRII. In conclusion, the utilization of proteasomal activators in conjunction with HSP90 inhibitors ushers in a promising frontier for the management of PF.

Sapanisertib attenuates pulmonary fibrosis by modulating Wnt5a/mTOR signaling.

Sapanisertib is an orally bioavailable ATP-dependent high-potential raptor-mTOR (TORC1) inhibitor with antineoplastic activity. Here, the impact of sapanisertib was assessed on transforming growth factor-β1 (TGF-β1)-treated L929 and A549 cells and on a rat model of bleomycin pulmonary fibrosis. First, in A549 cells treated with TGF-β1, sapanisertib significantly suppressed the TGF-β1-induced epithelial-mesenchymal transition, with elevated and reduced E-cadherin and vimentin expression, respectively. In L929 cells treated with TGF-β1, sapanisertib significantly blocked the TGF-β1-induced cell proliferation, with decreases in the extracellular matrix-related proteins collagens I and III and smooth muscle actin and in the mechanism-related proteins hypoxia-inducing factor, mTOR, p70S6K, and Wnt5a. Compared with bleomycin alone, continuous gavage administration of sapanisertib for 14 days reduced pathological scores in bleomycin-induced pulmonary fibrosis rats, with decreases in collagen deposition and in the same proteins as in L929 and A549 cells. Accordingly, our findings show that sapanisertib can ameliorate experimental pulmonary fibrosis by inhibiting Wnt5a/mTOR/HIF-1α/p70S6K.

Suppression of NLRP3 inflammasome by ivermectin ameliorates bleomycin-induced pulmonary fibrosis

Ivermectin is a US Food and Drug Administration (FDA)-approved antiparasitic agent with antiviral and anti-inflammatory properties. Although recent studies reported the possible anti-inflammatory activity of ivermectin in respiratory injuries, its potential therapeutic effect on pulmonary fibrosis (PF) has not been investigated. This study aimed to explore the ability of ivermectin (0.6 mg/kg) to alleviate bleomycin-induced biochemical derangements and histological changes in an experimental PF rat model. This can provide the means to validate the clinical utility of ivermectin as a treatment option for idiopathic PF. The results showed that ivermectin mitigated the bleomycin-evoked pulmonary injury, as manifested by the reduced infiltration of inflammatory cells, as well as decreased the inflammation and fibrosis scores. Intriguingly, ivermectin decreased collagen fiber deposition and suppressed transforming growth factor-β1 (TGF-β1) and fibronectin protein expression, highlighting its anti-fibrotic activity. This study revealed for the first time that ivermectin can suppress the nucleotide-binding oligomerization domain (NOD)-like receptor family pyrin domain-containing protein 3 (NLRP3) inflammasome, as manifested by the reduced gene expression of NLRP3 and the apoptosis-associated speck-like protein containing a caspase recruitment domain (ASC), with a subsequent decline in the interleukin-1β (IL-1β) level. In addition, ivermectin inhibited the expression of intracellular nuclear factor-κB (NF-κB) and hypoxia-inducible factor-1α (HIF-1α) proteins along with lowering the oxidative stress and apoptotic markers. Altogether, this study revealed that ivermectin could ameliorate pulmonary inflammation and fibrosis induced by bleomycin. These beneficial effects were mediated, at least partly, via the downregulation of TGF-β1 and fibronectin, as well as the suppression of NLRP3 inflammasome through modulating the expression of HIF-1α and NF-κB.

Fu-Zheng-Tong-Luo formula promotes autophagy and alleviates idiopathic pulmonary fibrosis by controlling the Janus kinase 2/signal transducer and activator of transcription 3 pathway

Ethnopharmacological relevanceFu-Zheng-Tong-Luo (FZTL) formula is a Chinese herbal prescription which is used to treat idiopathic pulmonary fibrosis (IPF). We previously reported that the FZTL formula could improve IPF injury in rats; however, the mechanism remains unelucidated. Aim of the studyTo elucidate the effects and mechanisms of the FZTL formula on IPF. Materials and methodsThe bleomycin-induced pulmonary fibrosis rat model and transforming growth factor-β-induced lung fibroblast model were used. Histological changes and fibrosis formation were detected in the rat model after treatment with the FZTL formula. Furthermore, the effects of the FZTL formula on autophagy and lung fibroblast activation were determined. Moreover, the mechanism of FZTL was explored using transcriptomics analysis. ResultsWe observed that FZTL alleviated IPF injury in rats and inhibited inflammatory responses and fibrosis formation in rats. Moreover, it promoted autophagy and inhibited lung fibroblast activation in vitro. Transcriptomics analysis revealed that FZTL regulates the Janus kinase 2 (JAK)/signal transducer and activator of the transcription 3 (STAT) signaling pathway. The JAK2/STAT3 signaling activator interleukin 6 inhibited the anti-fibroblast activation effect of the FZTL formula. Combined treatment with the JAK2 inhibitor (AZD1480) and autophagy inhibitor (3-methyladenine) did not enhance the antifibrotic effect of FZTL. ConclusionsThe FZTL formula can inhibit IPF injury and lung fibroblast activation. Its effects are mediated via the JAK2/STAT3 signaling pathway. The FZTL formula may be a potential complementary therapy for pulmonary fibrosis.

Pachymic acid ameliorates bleomycin-induced pulmonary fibrosis through inhibiting endoplasmic reticulum stress in rats.

The effect of pachymic acid (PA) on pulmonary fibrosis in rats was expected to be investigated in this study. Firstly, bleomycin (BLM) was used to establish pulmonary fibrosis rat model, then PA (10, 20, or 40 mg/kg) was intragastrically administered to the rats for 14 days. Subsequently, a variety of tests was performed to observe changes in sample tissues after different treatments. Briefly, the degree of pulmonary edema in rats was assessed through dry/wet weight ratio. Hematoxylin and eosin (H&E) staining and Masson's trichrome staining were used to observe the pathological injury and fibrosis of lung tissue. Biochemical kits were applied to measure the levels of hydroxyproline (Hyp), transforming growth factor beta-1 (TGFβ-1), malondialdehyde (MDA), reactive oxygen species (ROS), and adenosine triphosphate (ATP) and the activities of superoxide dismutase (SOD) and catalase (CAT) in rat lung tissues of each group. The mitochondrial DNA (mtDNA) copy number in rat lung tissue was tested using qRT-PCR. Additionally, the western blot was employed to detect the expression levels of pulmonary fibrosis-related proteins and endoplasmic reticulum (ER) stress-related proteins in each group of rat lung tissue. By virtue of experimental verification above, PA was discovered to alleviate BLM-induced pulmonary edema, pulmonary fibrosis and histopathological damage. On the one hand, PA treatment decreased Hyp and TGF-β1 levels and down-regulated pulmonary fibrosis-related protein expression [collagen I, α-smooth muscle actin (α-SMA), and fibronectin] in the lung tissue of BLM rats. On the other hand, it significantly increased the levels of SOD, CAT and ATP while decreased the activities of MDA and ROS in BLM rat lung tissues. In addition, the expression levels of ER stress-related proteins [glucose-regulated protein 78 (GRP78), C/EBP homologous protein (CHOP), Caspase 9, and activating transcription factor 4 (ATF4)] were significantly down-regulated in the lung tissue of BLM rats after PA treatment. Collectively, PA may ameliorate BLM-induced pulmonary fibrosis and histopathological damage in rats through inhibiting ER stress and improving mitochondrial function.

Protective effects of methylprednisolone–cyclophosphamide treatment on bleomycin-induced pulmonary fibrosis

BackgroundMethylprednisolone (MP) and cyclophosphamide (CTX) combination treatment has shown great benefits in improving pulmonary fibrosis (PF) and high safety. Currently, the mechanism underlying the effects of MP-CTX on improving PF remains unclear. This study determined the effects of MP-CTX combination treatment on the modulation of inflammation, oxidative stress, and T-cell immunity in PF. MethodsPF rat models were induced by bleomycin stimulation. MP (3 mg/kg) and MP-CTX (MP: 3 mg/kg; CTX: 8 mg/kg) combination were administered in the PF + MP and PF + MP + CTX groups, respectively. Transmission electron microscopy, hematoxylin and eosin staining, Ashcroft score, and Masson trichrome staining were performed to measure lung morphology in PF. Enzyme-linked immunosorbent assay and quantitative polymerase chain reaction assay were performed to quantify inflammatory factors. Malondialdehyde (MDA), superoxide dismutase (SOD), and glutathione peroxidase (GSH-PX) levels were determined using commercial kits. α-Smooth muscle actin (SMA) and collagen I levels were determined using western blotting and immunohistochemistry. The T-cell count was evaluated using flow cytometry. ResultsMP-CTX reduced lung injury, collagen deposition, and α-SMA and collagen I levels in a bleomycin-induced PF rat model. Additionally, MP-CTX decreased the levels of MDA and inflammatory factors (tumor necrosis factor-α, interleukin-1β, and interleukin-6) but increased the activities of SOD and GSH-PX. Furthermore, MP-CTX changed T-cell types in lung tissues, such as increasing CD4+CD25+Foxp3+ cell count. ConclusionsMP-CTX combination treatment improved the degree of PF by reducing inflammation and oxidative stress and improving T-cell immunity. These findings provide novel insights into the mechanisms underlying the effects of MP-CTX on PF.

Synergistic effect of constituent drugs of Baibutang on improving Yin-deficiency pulmonary fibrosis in rats.

Baibutang (BBT) is an ancient prescription for the treatment of pulmonary fibrosis. Previous experiments have shown that BBT had a good therapeutic effect on pulmonary fibrosis. However, there had been no study on the synergy between drugs composed of BBT. Due to the interaction between the constituent drugs, exploring their synergy profile is of great significance for explaining the essence of BBT's efficacy in improving pulmonary fibrosis. Based on the pharmacodynamic value, this study aimed to explore a method for the evaluation of the synergy profile between constituent drugs in traditional Chinese medicine (TCM) compounds. Nine herbs of BBT were divided into Zhikeqingre (ZK), Yangyinyiqi (YY) and Lishijianpi (LS) groups. A rat model of Yin-deficiency pulmonary fibrosis induced by thyroxine-bleomycin was used to evaluate the effects of BBT and the three groups. The pathological changes of lung tissue and the changes of biomarkers associated with fibrosis, Yin-deficiency and water-fluid metabolism were detected. After standardization of pharmacodynamics value (PV), the compatibility coefficient (CC) of the three groups, the relative PV (RPV) and contribution value (CV) of each group on every index were calculated. The average CC on fibrosis indexes was 0.44, indicating that 44% of the efficacy of BBT came from the synergistic effect of the three groups. ZK group had the highest RPV (0.80) in improving fibrosis indexes such as histopathological changes, α-SMA, collagen-I and renin-angiotensin system. The average CC on Yin-deficiency indexes was 0.25, and YY group had the highest RPV (0.96) in improving deficiency indexes such as body temperature, cAMP/cGMP ratio, and PDEs, PGE2 and COX-2 levels. The average CC on water-fluid metabolism indexes was 0.15, and LS group had the highest RPV (1.52) in improving water-fluid metabolism indexes such as aquaporins, mucins, and surfactant proteins. The results also showed that 29% of the improvement effect of BBT on all indexes came from the synergistic effect of the three groups, and the contribution of ZK, YY and LS groups to the efficacy of BBT were 25%, 25% and 21%, respectively. The established semiquantitative method can clearly and simply evaluate the synergy of the three groups in BBT, which will help to promote the research on the synergy of TCM compounds and other multiple-components combinations.

MiR-155-5p/FOXO3a promotes pulmonary fibrosis in rats by mediating NLRP3 inflammasome activation

Objective Pulmonary fibrosis (PF) is regarded as progressive lung disease. miR-155-5p depletion exerts anti-fibrotic effects in silicotic mice. This study explored the effect and possible mechanism of miR-155-5p in PF rats, hoping to find a new target for PF management. Methods Bleomycin-induced PF rat model was established. Alveolar structure and collagen fiber deposition were observed by HE and Elastica-Masson staining. Alveolitis and PF scores were evaluated using the method of Szapiel. Total collagen content was detected using the Sircol method. PF rats were intraperitoneally injected with NLRP3 inhibitor MCC950 or intravenously injected with miR-155-5p antagomir and si-FOXO3a lentivirus plasmids. Binding sites of miR-155-5p and FOXO3a were predicted using bioinformatics analysis and dual-luciferase reporter assay. The expressions of miR-155-5p, NLRP3, ASC, caspase-1, IL-1β, IL-18, and FOXO3a were detected by RT-qPCR, Western blot, and ELISA. Results MCC950 treatment inhibited NLRP3 inflammasome, alleviated alveolar hemorrhage and alveolitis, and reduced blue collagen fiber deposition, scores of alveolitis and PF, and levels of NLRP3, ASC, caspase-1, IL-1β, and IL-18 in PF rats. miR-155-5p was elevated in lung tissues of PF rats. Inhibition of miR-155-5p downregulated levels of NLRP3, ASC, caspase-1, IL-1β, and IL-18 in lung tissues of PF rats. miR-155-5p targeted FOXO3a. miR-155-5p inhibition and silencing FOXO3a exacerbated alveolitis and PF in rats and increased levels of NLRP3, ASC, caspase-1, IL-1β, and IL-18. Conclusions miR-155-5p aggravated alveolitis and promoted PF by targeting FOXO3a and prompting the activation of NLRP3 inflammasome and then inducing IL-1β and IL-18 release.

Molecular mechanism by which the Notch signaling pathway regulates autophagy in a rat model of pulmonary fibrosis in pigeon breeder's lung.

This study investigated the molecular mechanisms underlying the involvement of the Notch signaling pathway and autophagy in the development of pulmonary fibrosis in pigeon breeder's lung (PBL). Rats were divided into control (Ctrl), PBL model (M), M + D (Notch signaling inhibition), M + W (autophagy inhibition), and M + R (autophagy induction) groups. Lyophilized protein powder from pigeon shedding materials was used as an allergen to construct a fibrotic PBL rat model. The mechanism by which Notch signaling regulated autophagy in the pulmonary fibrosis of PBL was investigated by inhibiting the Notch pathway and interfering with autophagy. Pulmonary interstitial fibrosis was significantly greater in the M group and the M + W group than in the M + D and M + R groups. The expression of α-smooth muscle actin was significantly higher in the M, M + D, and M + W groups than in the Ctrl group (P < 0.05). The expression of the cell autophagy markers Beclin1 and LC3 was lower in the M, M + D, and M + W groups than in the Ctrl group (P < 0.05), whereas Beclin1 and LC3 expressions were higher in the M + D and M + R groups than in the M group. The levels of reactive oxygen species in serum and lung tissues were higher in the M, M + D, M + W, and M + R groups than in the Ctrl group (P < 0.05). The Notch signaling pathway is involved in the pathological process of pulmonary fibrosis in the rat model of PBL by regulating autophagy.

Vinpocetine's immunomodulating, anti-oxidant, anti-inflammatory, ant-ifibrotic, and PDE inhibiting potencies ameliorate bleomycin-induced pulmonary fibrosis.

Pulmonary fibrosis (PF) is a global health problem with a high economic burden. Intratracheal administration of bleomycin is the best model that resembles the pathogenesis of PF in humans. Recently, vinpocetine proved to have neuroprotective, cardioprotective, hepatoprotective, anti-aging, and antifibrotic effects through its anti-oxidant, immunomodulating, and anti-inflammatory activities. The present study investigated the antifibrotic potentiality of vinpocetine in a rat model of PF induced by intratracheal bleomycin administration. PF induced by a single intratracheal instillation of 5 mg/kg bleomycin in nine-week-old Wister rats. Oral vinpocetine was used at doses of 5, 10, or 20 mg/kg to treat PF for 21 days immediately after the bleomycin instillation. Vinpocetine dose-dependently ameliorates PF induced by bleomycin administration since vinpocetine effectively restored the normal body weight gain rates, pulmonary architecture, and collagen fiber distribution and suppressed the elevated BALF cell count, lymphocytes and neutrophils percentage, BALF, IL-6, TNF-α, and TGF-β1 levels and LDH activity, lung tissue MDA level, PDE activity, hydroxyproline content, immunohistochemical expression of α-SMA and CD68 positive macrophage, and fibrosis score. Meanwhile, it efficiently augmented the reduced BALF macrophage percentage, IL-10 level, lung tissue GSH level, CAT, and SOD activities. Vinpocetine may propose a new promising agent to manage PF.

Repositioning itraconazole for amelioration of bleomycin-induced pulmonary fibrosis: Targeting HMGB1/TLR4 Axis, NLRP3 inflammasome/NF-κB signaling, and autophagy

Background and aimsBleomycin (BLM) is one of the antitumor medications that had proven efficacy in the treatment of a wide range of malignant conditions. Pulmonary fibrosis which is frequently encountered during the course of bleomycin therapy may significantly reduce the potential efficacy of bleomycin in cancer therapy. This study tested the hypothesis that itraconazole may have mitigating effects on BLM-induced pulmonary fibrosis and tried to delineate the potential mechanisms of these effects. Materials and methodsIn a rat model of pulmonary fibrosis elicited by BLM, the effect of different doses of itraconazole was explored at the biochemical, histopathological, and electron microscopic levels. Key findingsItraconazole, in a dose-dependent manner, exhibited significant effects on the pro-oxidant/antioxidant balance, the inflammatory consequences, high-mobility group box 1/toll-like receptor-4 Axis, autophagy and nuclear factor kappa B/Nod-like receptor protein 3 inflammasome signaling and alleviated the histopathological, immunohistochemical, and electron microscopic perturbations induced by BLM in the pulmonary tissues. SignificanceIn view of the afore-mentioned data, itraconazole may be a promising drug that efficiently mitigates the deleterious effects of BLM on the pulmonary tissues.