Pulmonary fibrosis is end-stage of variety of heterogeneous interstitial lung disease, characterizedby excessive proliferation of fibroblasts and extracellular matrix deposition and destruction of lung parenchyma. Thyroid and lung are derived from the same endodermal cells, thyroid hormone affect the occurrence、development and prognosis of the chronic obstructive pulmonary disease, lung cancer and other lung diseases, This article reviews the role and mechanism of thyroid hormone in pulmonary fibrosis in order to provide new idea for the study of the role and mechanism of thyroid hormone in silicosis.
Humans ; Pulmonary Fibrosis/pathology* ; Lung/pathology* ; Silicosis ; Lung Diseases, Interstitial ; Fibroblasts ; Thyroid Hormones ; Fibrosis

Pulmonary fibrosis is the end-stage pathological change of lung diseases, which seriously affects the respiratory function of human body. A large number of studies at home and abroad have confirmed that epithelial-mesenchymal transition (EMT) is an important intermediate stage in the development of pulmonary fibrosis. Inhibition of multiple pathways upstream and downstream of EMT, such as the classical Smads pathway and non-Smads pathway of TGF-1 can effectively inhibit the process of EMT and alleviate pulmonary fibrosis. This article will review the main conclusions of the mechanism of action of EMT as a target to improve the pathology of pulmonary fibrosis so far, and provide a theoretical basis and research direction for further research and development of anti-pulmonary fibrosis drugs.
Humans ; Epithelial-Mesenchymal Transition/drug effects* ; Fibrosis/drug therapy* ; Pulmonary Fibrosis/pathology* ; Signal Transduction ; Transforming Growth Factor beta1/metabolism* ; Antifibrotic Agents/therapeutic use*

Objective: To construct paraquat (PQ) poisoning rat model and to explore the effect of pirfenidone (PFD) on PQ-induced pulmonary fibrosis. Methods: In April 2017, male 6-8 week-old Wistar rats were selected, and PQ was administered intraperitoneally at one time. PFD was administered by gavage 2 hours after poisoning. The daily gavage doses were 100, 200 and 300 mg/kg, and the rats were divided into physiological saline group, PQ group, PQ+PFD 100 group, PQ+PFD 200 group, PQ+PFD 300 group, with 10 rats in each group at each observation time point. The pathological changes of lung tissue at different time points (the 1st, 3rd, 7th, 14th, 28th, 42nd and 56th days) after poisoning and the effect of PFD intervention with different dose on PQ-induced pulmonary fibrosis were observed. Pathological evaluation of lung tissue was performed by Ashcroft scale method. The PQ+PFD 200 group was selected to further explore the pathological changes of lung tissue, the contents of hydroxyproline and malondialdehyde in lung tissue were determined.And the tumor necrosis factor (TNF) -α, interleukin (IL) -6, transforming growth factor (TGF) -β1, fibroblast growth factor (FGF) -B, platelet-derived growth factor (PDGF) -AB, insulin-like growth factor (IGF) -1 and PQ concentrations in serum and lung tissue were determined. Results: On the 1st to 7th day after PQ exposure, rats developed lung inflammation, which was aggravated on the 7th to 14th day, and pulmonary fibrosis appeared on the 14th to 56th day. Compared with PQ group, the Ashcroft scores of lung fibrosis in PQ+PFD 200 group and PQ+PDF 300 group decreased significantly in 7th and 28th day (P<0.05), while the Ashcroft score of lung fibrosis in PQ+PFD 100 group had no significant difference (P>0.05). After PQ exposure, the content of hydroxyproline in lung tissue increased gradually and reached the peak value on the 28th day. Compared with the PQ group, the contents of hydroxyproline in the PQ+PFD 200 group decreased at the 7th, 14th and 28th day, and the contents of malondialdehyde decreased at the 3rd and 7th day, the differences were statistically significant (P<0.05). The levels of TNF-α, IL-6 in rat serum and lung tissue reached the peak value on the 7th day after PQ exposure, and the levels of TGF-β1, FGF-B and IGF-1 in rat serum and lung tissue reached the peak value on the 14th day after PQ exposure, and the level of PDGF-AB in rat serum and lung tissue reached the peak value on the 28th day after PQ exposure. Compared with PQ group, the level of serum IL-6 in PQ+PFD 200 group decreased significantly on the 7th day, and serum TGF-β1, FGF-B, PDGF-AB and IGF-1 on the 14th and 28th day were decreased significantly (P<0.05). The levels of TNF-α, IL-6 in lung tissue of rats in PQ+PFD 200 group on the 7th day decreased significantly, and the levels of TGF-β1, FGF-B and IGF-1 in lung tissue of rats on the 14th day were significantly decreased, and the level of PDGF-AB in lung tissue of rats on the 28th day were significantly decreased (P<0.05) . Conclusion: PFD partially alleviates the PQ-induced lung inflammation and fibrosis by inhibiting oxidative stress, reducing the levels of pro-inflammatory and pro-fibrotic cytokines in serum and lung tissue, but does not affect the concentrations of PQ in serum and lung tissue.
Male ; Rats ; Animals ; Pulmonary Fibrosis/chemically induced* ; Insulin-Like Growth Factor I ; Paraquat ; Transforming Growth Factor beta1 ; Hydroxyproline ; Interleukin-6 ; Tumor Necrosis Factor-alpha ; Rats, Wistar ; Malondialdehyde

Idiopathic pulmonary fibrosis (IPF) is a chronic progressive lung disease characterized by progressive lung fibrogenesis and histological features of usual interstitial pneumonia. IPF has a poor prognosis and presents a spectrum of disease courses ranging from slow evolving disease to rapid deterioration; thus, a differential diagnosis remains challenging. Several biomarkers have been identified to achieve a differential diagnosis; however, comprehensive reviews are lacking. This review summarizes over 100 biomarkers which can be divided into six categories according to their functions: differentially expressed biomarkers in the IPF compared to healthy controls; biomarkers distinguishing IPF from other types of interstitial lung disease; biomarkers differentiating acute exacerbation of IPF from stable disease; biomarkers predicting disease progression; biomarkers related to disease severity; and biomarkers related to treatment. Specimen used for the diagnosis of IPF included serum, bronchoalveolar lavage fluid, lung tissue, and sputum. IPF-specific biomarkers are of great clinical value for the differential diagnosis of IPF. Currently, the physiological measurements used to evaluate the occurrence of acute exacerbation, disease progression, and disease severity have limitations. Combining physiological measurements with biomarkers may increase the accuracy and sensitivity of diagnosis and disease evaluation of IPF. Most biomarkers described in this review are not routinely used in clinical practice. Future large-scale multicenter studies are required to design and validate suitable biomarker panels that have diagnostic utility for IPF.
Humans ; Idiopathic Pulmonary Fibrosis/diagnosis* ; Biomarkers ; Lung Diseases, Interstitial ; Lung ; Bronchoalveolar Lavage Fluid ; Disease Progression ; Prognosis

Idiopathic pulmonary fibrosis (IPF) is a progressive and fatal interstitial lung disease, the cause is not yet clear. Pathological manifestations are abnormal repair changes resulting from sustained lung injury. Macrophages have been identified as playing a key role in IPF pathogenesis. In different local microenvironments, macrophages can exhibit either classically activated (M1) or alternately activated (M2) phenotypes. M1 plays a key role in promoting inflammatory response and is involved in the process of causing alveolar tissue injury. M2 is involved in wound healing and stopping lung inflammation. Previous studies have shown that activation of 5-hydroxytryptamine (5-HT) signaling is enhanced in pulmonary fibrosis and that 5-HT receptors play an important role in the observed pro-fibrotic effects. As a multifunctional signaling molecule, 5-HT is closely related to lung macrophage polarization, early lung tissue injury, abnormal proliferation and repair, and late extracellular matrix (ECM) deposition. This article reviewed the role of 5-HT and M2 macrophages in the pathogenesis of IPF and the possible regulatory mechanism of 5-HT, in order to provide a reference for further research.
Humans ; Serotonin ; Macrophages ; Lung Diseases, Interstitial/pathology* ; Lung/pathology* ; Idiopathic Pulmonary Fibrosis ; Fibrosis

OBJECTIVE: To demonstrate the mechanism of mechanical ventilation (MV) induced endoplasmic reticulum stress (ERS) promoting mechanical ventilation-induced pulmonary fibrosis (MVPF), and to clarify the role of angiotensin receptor 1 (AT1R) during the process. METHODS: The C57BL/6 mice were randomly divided into four groups: Sham group, MV group, AT1R-shRNA group and MV+AT1R-shRNA group, with 6 mice in each group. The MV group and MV+AT1R-shRNA group mechanically ventilated for 2 hours after endotracheal intubation to establish MVPF animal model (parameter settings: respiratory rate 70 times/minutes, tidal volume 20 mL/kg, inhated oxygen concentration 0.21). The Sham group and AT1R-shRNA group only underwent intubation after anesthesia and maintained spontaneous breathing. AT1R-shRNA group and MV+AT1R-shRNA group were airway injected with the adeno-associated virus one month before modeling to inhibit AT1R gene expression in lung tissue. The expressions of AT1R, ERS signature proteins [immunoglobulin heavy chain-binding protein (BIP), protein disulfide isomerase (PDI)], fibrosis signature proteins [collagen I (COL1A1), α-smooth muscle actin (α-SMA)] in lung tissues were detected by immunofluorescence and Western blotting. Hematoxylin-eosin (HE) staining was used to evaluate lung injury and Masson staining was used to evaluate pulmonary fibrosis. RESULTS: Compared with the Sham group, the degree of pulmonary fibrosis and lung injury were more significant in the MV group. In the MV group, the protein expressions of AT1R, BIP, PDI, COL1A1 and α-SMA were increased (AT1R/β-actin: 1.40±0.02 vs. 1, BIP/β-actin: 2.79±0.07 vs. 1, PDI/β-actin: 2.07±0.02 vs. 1, COL1A1/α-Tubulin: 2.60±0.15 vs. 1, α-SMA/α-Tubulin: 2.80±0.25 vs. 1, all P < 0.01). The number of E-cad⁺/AT1R⁺ and E-cad⁺/BIP⁺ cells in lung tissue increased, and the fluorescence intensity of COL1A1 and α-SMA increased. Compared with the MV group, the degree of pulmonary fibrosis and lung injury were significantly relieved in the MV+AT1R-shRNA group. In the MV+AT1R-shRNA group, the protein expressions of AT1R, BIP, PDI, COL1A1 and α-SMA were decreased (AT1R/β-actin: 0.53±0.03 vs. 1.40±0.02, BIP/β-actin: 1.73±0.15 vs. 2.79±0.07, PDI/β-actin: 1.04±0.07 vs. 2.07±0.02, COL1A1/α-Tubulin: 1.29±0.11 vs. 2.60±0.15, α-SMA/α-Tubulin: 1.27±0.10 vs. 2.80±0.25, all P < 0.01). The number of E-cad⁺/AT1R⁺ and E-cad⁺/BIP⁺ cells in lung tissue decreased, and the fluorescence intensity of COL1A1 and α-SMA decreased. There was no statistically significant difference in the indicators between AT1R-shRNA group and Sham group. CONCLUSIONS MV up-regulate the expression of AT1R in alveolar epithelial cells, activate the AT1R pathway, induce ERS and promote the progression of MVPF.
Mice ; Animals ; Pulmonary Fibrosis/chemically induced* ; Lung Injury ; Respiration, Artificial/adverse effects* ; Actins/metabolism* ; Tubulin ; Mice, Inbred C57BL ; Endoplasmic Reticulum Stress ; RNA, Small Interfering

OBJECTIVE: To observe whether metformin (MET) inhibits transforming growth factor-β₁ (TGF-β₁)/Smad3 signaling pathway by activating adenosine activated protein kinase (AMPK), so as to alleviate the pulmonary fibrosis caused by paraquat (PQ) poisoning in mice. METHODS: Male C57BL/6J mice were randomly divided into the Control group, PQ poisoning model group (PQ group), MET intervention group (PQ+MET group), AMPK agonist group (PQ+AICAR group), and AMPK inhibitor group (PQ+MET+CC group), according to a random number table method. A mouse model of PQ poisoning was established by one-time peritoneal injection of 1 mL PQ solution (20 mg/kg). The Control group was injected with the same volume of normal saline. After 2 hours of modeling, the PQ+MET group was given 2 mL of 200 mg/kg MET solution by gavage, the PQ+AICAR group was given 2 mL of 200 mg/kg AICAR solution by intraperitoneal injection, the PQ+MET+CC group was given 2 mL of 200 mg/kg MET solution by gavage and then 1 mL complex C (CC) solution (20 mg/kg) was intraperitoneally injected, the Control group and PQ group were given 2 mL of normal saline by gavage. The intervention was given once a day for 21 consecutive days. The 21-day survival rate of ten mice in each group was calculated, and the lung tissues of remaining mice were collected at 21 days after modeling. The pathological changes of lung tissues were observed under light microscope after hematoxylin-eosin (HE) staining and Masson staining, and the degree of pulmonary fibrosis was evaluated by Ashcroft score. The content of hydroxyproline in lung tissue and oxidative stress indicators such as malondialdehyde (MDA) and superoxide dismutase (SOD) were detected. The protein expressions of E-cadherin, α-smooth muscle actin (α-SMA), phosphorylated AMPK (p-AMPK), TGF-β₁ and phosphorylated Smad3 (p-Smad3) in lung tissue were detected by Western blotting. RESULTS: Compared with the Control group, the 21 days survival rate was significantly reduced, lung fibrosis and Ashcroft score were significantly increased in PQ group. In addition, the content of hydroxyproline, MDA and the protein expressions of α-SMA, TGF-β₁ and p-Smad3 in lung tissue were significantly increased, while the activity of SOD and the protein expressions of E-cadherin and p-AMPK were significantly decreased in PQ group. Compared with the PQ group, the 21 days survival rates of mice were significantly improved in the PQ+MET group and PQ+AICAR group (70%, 60% vs. 20%, both P < 0.05). The degree of pulmonary fibrosis and the Ashcroft score were significantly reduced (1.50±0.55, 2.00±0.63 vs. 6.67±0.52, both P < 0.05). The content of hydroxyproline and MDA in lung tissue, as well as α-SMA, TGF-β₁ and p-Smad3 protein expressions were significantly reduced [hydroxyproline (mg/L): 2.03±0.11, 3.00±0.85 vs. 4.92±0.65, MDA (kU/g): 2.06±1.48, 2.10±1.80 vs. 4.06±1.33, α-SMA/GAPDH: 0.23±0.06, 0.16±0.06 vs. 1.00±0.09, TGF-β₁/GAPDH: 0.28±0.03, 0.53±0.05 vs. 0.92±0.06 p-Smad3/GAPDH: 0.52±0.04, 0.69±0.06 vs. 1.11±0.10, all P < 0.05], SOD activity and the protein expressions of E-cadherin and p-AMPK were significantly increased [SOD (μmol/g): 39.76±1.35, 33.03±1.28 vs. 20.08±1.79, E-cadherin/GAPDH: 0.91±0.08, 0.72±0.08 vs. 0.26±0.04, p-AMPK/GAPDH: 0.62±0.04, 0.60±0.01 vs. 0.20±0.04, all P < 0.05]. However, these protective effects of MET were inhibited by the addition of AMPK inhibitor CC solution. CONCLUSIONS MET can effectively alleviate the degree of pulmonary fibrosis in mice poisoned with PQ, and its mechanism may be related to the activation of AMPK and inhibition of TGF-β₁/Smad3 signaling pathway, which can be inhibited by AMPK inhibitor CC.
Mice ; Male ; Animals ; Pulmonary Fibrosis/drug therapy* ; Paraquat ; AMP-Activated Protein Kinases/pharmacology* ; Metformin/pharmacology* ; Hydroxyproline/pharmacology* ; Saline Solution ; Mice, Inbred C57BL ; Lung/metabolism* ; Transforming Growth Factor beta1/pharmacology* ; Cadherins ; Superoxide Dismutase

BACKGROUND: Acute exacerbation of idiopathic pulmonary fibrosis (AE-IPF) is an important occurrence in the natural history of idiopathic pulmonary fibrosis (IPF), associated with high hospitalization rates, high mortality and poor prognosis. At present, there is no effective treatment for AE-IPF. Chinese herbal medicine has some advantages in treating IPF, but its utility in AE-IPF is unclear. OBJECTIVE: The treatment of AE-IPF with Kangxian Huanji Granule (KXHJ), a compound Chinese herbal medicine, lacks an evidence-based justification. This study explores the efficacy and safety of KXHJ in patients with AE-IPF. DESIGN, SETTING, PARTICIPANTS AND INTERVENTIONS: We designed a randomized, double-blind, placebo-controlled, exploratory clinical trial. A total of 80 participants diagnosed with AE-IPF were randomly assigned to receive KXHJ or a matching placebo; the treatment included a 10 g dose, administered twice daily for 4 weeks, in addition to conventional treatment. Participants were followed up for 12 weeks after the treatment. MAIN OUTCOME MEASURES: The primary endpoints were treatment failure rate and all-cause mortality. Secondary endpoints included the length of hospitalization, overall survival, acute exacerbation rate, intubation rate, the modified British Medical Research Council (mMRC) score, and the St George's Respiratory Questionnaire for IPF (SGRQ-I) score. RESULTS: The rate of treatment failure at 4 weeks was lower in the intervention group compared to the control group (risk ratio [RR]: 0.22; 95% confidence interval [CI]: 0.051 to 0.965, P = 0.023). There was no significant difference in all-cause mortality at 16 weeks (RR: 0.75; 95% CI: 0.179 to 3.138; P > 0.999) or in the acute exacerbation rate during the 12-week follow-up period (RR: 0.69; 95% CI: 0.334 to 1.434; P = 0.317). The intervention group had a shorter length of hospitalization than the control group (mean difference [MD]: -3.30 days; 95% CI, -6.300 to -0.300; P = 0.032). Significant differences in the mean change from baseline in the mMRC (between-group difference: -0.67; 95% CI: -0.89 to -0.44; P < 0.001) and SGRQ-I score (between-group difference: -10.36; 95% CI: -16.483 to -4.228; P = 0.001) were observed after 4 weeks, and also in the mMRC (between-group difference: -0.67; 95% CI: -0.91 to -0.43; P < 0.001) and SGRQ-I (between-group difference: -10.28; 95% CI, -15.838 to -4.718; P < 0.001) at 16 weeks. The difference in the adverse events was not significant. CONCLUSION: KXHJ appears to be effective and safe for AE-IPF and can be considered a complementary treatment in patients with AE-IPF. As a preliminary exploratory study, our results provide a basis for further clinical research. TRIAL REGISTRATION Chinese Clinical Trial Registry (ChiCTR1900026289). Please cite this article as: Li JS, Zhang HL, Guo W, Wang L, Zhang D, Zhao LM, Zhou M. Efficacy and safety of Kangxian Huanji Granule as adjunctive treatment in acute exacerbation of idiopathic pulmonary fibrosis: an exploratory randomized controlled trial. J Integr Med. 2023; 21(6): 543-549.
Humans ; Double-Blind Method ; Drugs, Chinese Herbal/therapeutic use* ; Idiopathic Pulmonary Fibrosis/drug therapy* ; Treatment Outcome

Pulmonary fibrosis is a severe lung interstitial disease characterized by the destruction of lung tissue structure, excessive activation and proliferation of fibroblasts, secretion and accumulation of a large amount of extracellular matrix (ECM), and impaired lung function. Due to the complexity of the disease, a suitable animal model to mimic human pulmonary fibrosis has not yet been established. Precision-cut lung slice (PCLS) has been a widely used in vitro method to study lung physiology and pathogenesis in recent years. This method is an in vitro culture technology at the level between organs and cells, because it can preserve the lung tissue structure and various types of airway cells in the lung tissue, simulate the in vivo lung environment, and conduct the observation of various interactions between cells and ECM. Therefore, PCLS can compensate for the limitations of other models such as cell culture. In order to explore the role of discoidin domain receptor 2 (DDR2) in pulmonary fibrosis, Ddr2^flox/flox mice were successfully constructed. The Cre-LoxP system and PCLS technology were used to verify the deletion or knockdown of DDR2 in mouse PCLS. Transforming growth factor β1 (TGF-β1) can induce fibrosis of mouse PCLS in vitro, which can simulate the in vivo environment of pulmonary fibrosis. In the DDR2 knock down-PCLS in vitro model, the expression of various fibrosis-related factors induced by TGF-β1 was significantly reduced, suggesting that knocking down DDR2 can inhibit the formation of pulmonary fibrosis. The results provide a new perspective for the clinical study of DDR2 as a therapeutic target in pulmonary fibrosis.
Animals ; Humans ; Mice ; Discoidin Domain Receptor 2/metabolism* ; Fibroblasts/pathology* ; Fibrosis ; Lung/pathology* ; Pulmonary Fibrosis/metabolism* ; Transforming Growth Factor beta1/metabolism*

This study aims to investigate the intervention effect of the aqueous extract of Epimedium sagittatum Maxim on the mouse model of bleomycin(BLM)-induced pulmonary fibrosis, so as to provide data support for the clinical treatment of pulmonary fibrosis. Ninety male C57BL/6N mice were randomized into normal(n=10), model(BLM, n=20), pirfenidone(PFD, 270 mg·kg~(-1), n=15), and low-, medium-, and high-dose E. sagittatum extract(1.67 g·kg~(-1), n=15; 3.33 g·kg~(-1), n=15; 6.67 g·kg~(-1), n=15) groups. The model of pulmonary fibrosis was established by intratracheal instillation of BLM(5 mg·kg~(-1)) in the other five groups except the normal group, which was treated with an equal amount of normal saline. On the day following the modeling, each group was treated with the corresponding drug by gavage for 21 days. During this period, the survival rate of the mice was counted. After gavage, the lung index was calculated, and the morphology and collagen deposition of the lung tissue were observed by hematoxylin-eosin(HE) and Masson staining, respectively. The levels of reactive oxygen species(ROS) in lung cell suspensions were measured by flow cytometry. The levels of glutathione peroxidase(GSH-Px), total superoxide dismutase(T-SOD), and malondialdehyde(MDA) the in lung tissue were measured. Terminal-deoxynucleoitidyl transferase-mediated nick-end labeling(TUNEL) was employed to examine the apoptosis of lung tissue cells. The content of interleukin-6(IL-6), chemokine C-C motif ligand 2(CCL-2), matrix metalloproteinase-8(MMP-8), transforming growth factor-beta 1(TGF-β1), alpha-smooth muscle actin(α-SMA), E-cadherin, collagen Ⅰ, and fibronectin in the lung tissue was measured by enzyme-linked immunosorbent assay(ELISA). The expression levels of F4/80, Ly-6G, TGF-β1, and collagen Ⅰ in the lung tissue were determined by immunohistochemistry. The mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue were determined by qRT-PCR. The content of hydroxyproline(HYP) in the lung tissue was determined by alkaline hydrolysation. The expression of α-SMA and E-cadherin was detected by immunofluorescence, and the protein levels of α-SMA, vimentin, E-cadherin in the lung tissue were determined by Western blot. The results showed the aqueous extract of E. sagittatum increased the survival rate, decreased the lung index, alleviated the pathological injury, collagen deposition, and oxidative stress in the lung tissue, and reduced the apoptotic cells. Furthermore, the aqueous extract of E. sagittatum down-regulated the protein levels of F4/80 and Ly-6G and the mRNA levels of CCL-2, IL-6, and MMP-7 in the lung tissue, reduced the content of IL-6, CCL-2, and MMP-8 in the alveolar lavage fluid. In addition, it lowered the levels of HYP, TGF-β1, α-SMA, collagen Ⅰ, fibronectin, and vimentin, and elevated the levels of E-cadherin in the lung tissue. The aqueous extract of E. sagittatum can inhibit collagen deposition, alleviate oxidative stress, and reduce inflammatory response by regulating the expression of the molecules associated with epithelial-mesenchymal transition, thus alleviating the symptoms of bleomycin-induced pulmonary fibrosis in mice.
Mice ; Male ; Animals ; Pulmonary Fibrosis/metabolism* ; Transforming Growth Factor beta1/metabolism* ; Epimedium/metabolism* ; Fibronectins/metabolism* ; Matrix Metalloproteinase 7/therapeutic use* ; Matrix Metalloproteinase 8/therapeutic use* ; Vimentin/metabolism* ; Interleukin-6/metabolism* ; Mice, Inbred C57BL ; Lung ; Collagen/metabolism* ; Bleomycin/toxicity* ; RNA, Messenger/metabolism* ; Cadherins/metabolism*