OBJECTIVE: To investigate the common mechanisms among collagen-induced arthritis (CIA), bleomycin (BLM)-induced pulmonary fibrosis, and CIA+BLM to evaluate the therapeutic effect of triptolide (TP) on CIA+BLM. METHODS: Thirty-six male Sprague-Dawley rats were randomly assigned to 6 groups according to a random number table (n=6 per group): normal control (NC), CIA, BLM, combined CIA+BLM model, TP low-dose (TP-L, 0.0931 mg/kg), and TP high-dose (TP-H, 0.1862 mg/kg) groups. The CIA model was induced by intradermal injection at the base of the tail with emulsion of bovine type II collagen and incomplete Freund's adjuvant (1:1), with 200 µL administered on day 0 and a booster of 100 µL on day 7. Pulmonary fibrosis was induced via a single intratracheal injection of BLM (5 mg/kg). The CIA+BLM model combined both protocols, and TP was administered orally from day 14 to 35. After successful modeling, arthritis scores were recorded every 3 days, and pulmonary function was assessed once at the end of the treatment period. Lung tissues were collected for histological analysis (hematoxylin eosin and Masson staining), immunohistochemistry, measurement of hydroxyproline (HYP) content, and calculation of lung coefficient. In addition, HE staining was performed on the ankle joint. Total RNA was extracted from lung tissues for transcriptomic analysis. Differentially expressed genes (DEGs) were compared with those from the RA-associated interstitial lung diseases patient dataset GSE199152 to identify overlapping genes, which were then used to construct a protein-protein interaction network. Hub genes were identified using multiple topological algorithms. RESULTS: The successfully established CIA+BLM rat model exhibited significantly increased arthritis scores and severe pulmonary fibrosis (P<0.01). By intersecting the DEGs obtained from transcriptomic analysis of lung tissues in CIA, BLM, and CIA+BLM rats with DEGs from rheumatoid arthritis-interstitial lung disease patients (GSE199152 dataset), 50 upregulated and 44 downregulated genes were identified. Through integrated PPI network analysis using multiple topological algorithms, IGF1 was identified as a central hub gene. TP intervention significantly improved pulmonary function by increasing peak inspiratory flow (P<0.01), and reduced lung index and HYP content (P<0.01). Histopathological analysis showed that TP alleviated alveolar collapse, interstitial thickening, and collagen deposition in the lung tissues (P<0.01). Moreover, TP treatment reduced the expression of collagen type I and α-SMA and increased E-cadherin levels (P<0.01). TP also significantly reduced arthritis scores and ameliorated synovial inflammation (P<0.05). Both transcriptomic and immunohistochemical analyses confirmed that IGF1 expression was elevated in the CIA+BLM group and downregulated following TP treatment (P<0.05). CONCLUSION TP exerts protective effects in the CIA+BLM model by alleviating arthritis and pulmonary fibrosis through the inhibition of IGF1-mediated EMT.
Animals ; Pulmonary Fibrosis/complications* ; Bleomycin/adverse effects* ; Phenanthrenes/pharmacology* ; Male ; Rats, Sprague-Dawley ; Diterpenes/pharmacology* ; Epoxy Compounds/therapeutic use* ; Arthritis, Experimental/complications* ; Insulin-Like Growth Factor I/metabolism* ; Rats ; Lung/physiopathology*

OBJECTIVE: To investigate the intervention of melatonin (MT) in the expression of circadian genes in patients with pulmonary fibrosis and to analyze the mechanism by which it alleviates the progression of pulmonary fibrosis. METHODS: By utilizing the Gene Expression Omnibus (GEO) database, we identified differentially expressed circadian genes between patients with pulmonary fibrosis and controls. We analyzed the correlation between circadian genes and pulmonary function as well as genes related to pulmonary fibrosis. A bleomycin-induced mouse model of pulmonary fibrosis (BLM group) was constructed to observe the expression differences of PER2 and CRY2 by sequencing and immunohistochemical staining in the BLM group and after MT intervention (BLM+MT group). Hematoxylin and eosin (HE) staining and Masson staining were used to observe the effects of MT on fibrosis. We used Western blot to detect the expression of P-smad2/3 in lung epithelial cells induced by transforming growth factor β (TGF-β). Reverse transcription quantitative real-time PCR technology was employed to investigate the rhythmic expression changes of circadian genes in the control group, TGF-β group, and TGF-β+MT group. Finally, luzindole, a MT receptor antagonist, was used to intervene in TGF-β+MT group, and Western blot was used to explore the receptor dependence of MT in alleviating TGF-β-induced epithelial-mesenchymal transition. RESULTS: (1) Analysis of the GEO dataset (GSE) revealed a negative correlation between circadian genes PER2 and CRY2 and the expression of TGF-β, and a positive correlation with pulmonary function indicators in patients. (2) Transcriptome sequencing analysis of lung tissue in BLM group found that the expression of PER2 and CRY2 was significantly reduced compared with the normal group. Histopathological staining results showed that the lung tissue structure of the normal group was intact and clear, with thin alveolar septa; in the BLM group, there was a large increase in collagen fibers and disordered alveolar structure; compared with the BLM group, the BLM+MT group had reduced collagen fiber proliferation and inflammatory cell infiltration; the expression of PER2 and CRY2 in the BLM group was lower than in the normal group, and the expression in the BLM+MT group was increased compared with the BLM group. (3) In vitro lung epithelial cell experiments with TGF-β intervention showed that compared with the control group, the expression of P-smad2/3 increased in the TGF-β group, and MT intervention inhibited the inducing effect of TGF-β on P-smad2/3, while intervention with the MT receptor antagonist reversed this phenomenon. The results indicated that MT could inhibit the activation of the TGF-β pathway, and this process was dependent on MT receptors. (4) The 48-hour rhythm experiment in lung epithelial cells showed that the mRNA rhythm of PER2 and CRY2 in the TGF-β+MT group was close to 24 hours and showed a trend towards restoring the rhythm of the control group, while the addition of the MT receptor blocker tended to make the rhythm duration and amplitude of both groups approach that of the TGF-β group. CONCLUSION MT, by binding to its receptors, can restore the periodic expression of the circadian genes PER2 and CRY2, thereby inhibiting the activation of the TGF-β classical pathway and suppressing the pathological process of epithelial-mesenchymal transition in pulmonary fibrosis. This finding provides new molecular targets and potential therapeutic strategies for the treatment of pulmonary fibrosis.
Melatonin/pharmacology* ; Animals ; Mice ; Pulmonary Fibrosis/chemically induced* ; Bleomycin ; Humans ; Transforming Growth Factor beta/metabolism* ; Period Circadian Proteins/metabolism* ; Smad3 Protein/genetics* ; Disease Models, Animal ; Lung/pathology* ; Cryptochromes/metabolism* ; Smad2 Protein/genetics* ; Epithelial Cells/metabolism* ; Mice, Inbred C57BL

Objective To investigate the effects and mechanism of Interleukin-33 (IL-33) mediated proliferation and differentiation of pulmonary myofibroblasts (MFbs) in pulmonary fibrosis (PF). Methods C57BL/6 mice were randomly divided into four groups: a control group, a bleomycin (BLM) group, a BLM combined with IL-33 group and a BLM combined with anti-IL-33 antibody group, 12 mice in each group. The PF model was induced by intratracheal injection of BLM (5000 U/kg). The degrees of fibrosis were examined using HE and Masson staining. ELISA was used to measure the plasma levels of IL-33. Immunohistochemical staining was used to measure the expression of alpha smooth muscle actin (α-SMA) in lung tissue. Primary pulmonary fibroblasts were isolated and cultured from lung tissues of mice. The cells were divided into four groups: a control group, an IL-33 group, an IL-33 combined with dimethyl sulfoxide (DMSO) group and an IL-33 combined with pyrrolidine dithiocarbamate (PDTC) group. The cells were treated with DMSO or PDTC for 1 hour and then with IL-33 for 48 hours. Cell proliferation was measured by 5-ethynyl-2'-deoxyuridine (EdU) assay and cell cycle was measured by flow cytometry. Transwell^TM assay was used to analyze cell migration. Real-time quantitative PCR was used to measure the expression of collagen type I (Col1), Col3 and α-SMA mRNA. The protein levels of IL-33, Col1, Col3, α-SMA, eukaryotic initiation factor 3a (eIF3a), phosphorylated IκBα (p-IκBα) (total lysate), p-NF-κB p65(total lysate) and NF-κB p65 (nucleus) were measured by Western blot analysis. Results In vivo, compared with the control group, the expressions of IL-33, p-IκBα (total lysate), p-NF-κB p65 (total lysate), NF-κB p65(nucleus), eIF3a, α-SMA, Col1 and Col3 in the BLM group significantly increased. Compared with the BLM group, the expressions of p-IκBα (total lysate), p-NF-κB p65 (total lysate), NF-κB p65 (nucleus), eIF3a, α-SMA, Col1 and Col3 in the IL-33 group increased further and the PF was further aggravated. But the effect of anti-IL-33 antibody was just opposite to that of IL-33. In vitro, IL-33 markedly induced the proliferation and migration of pulmonary fibroblasts, and significantly up-regulated the expression of p-IκBα (total lysate), p-NF-κB p65(total lysate), NF-κB p65 (nucleus), eIF3a, α-SMA, Col1 and Col3. But all these effects of IL-33 were reversed by pyrrolidine dithiocarbamate. Conclusion The results suggest that IL-33 may promote the expression of eIF3a by activating NF-κB signaling pathway, thus inducing the proliferation and differentiation of MFbs and promoting the occurrence and development of PF.
Animals ; Mice ; Bleomycin/metabolism* ; Cell Differentiation ; Cell Proliferation ; Dimethyl Sulfoxide/pharmacology* ; Fibroblasts ; Interleukin-33/pharmacology* ; Mice, Inbred C57BL ; Myofibroblasts/metabolism* ; NF-kappa B/metabolism* ; NF-KappaB Inhibitor alpha/metabolism* ; Pulmonary Fibrosis ; Signal Transduction

Objective: JWH133, a cannabinoid type 2 receptor agonist, was tested for its ability to protect mice from bleomycin-induced pulmonary fibrosis. Methods: By using a random number generator, 24 C57BL/6J male mice were randomly divided into the control group, model group, JWH133 intervention group, and JWH133+a cannabinoid type-2 receptor antagonist (AM630) inhibitor group, with 6 mice in each group. A mouse pulmonary fibrosis model was established by tracheal instillation of bleomycin (5 mg/kg). Starting from the first day after modeling, the control group mice were intraperitoneally injected with 0.1 ml of 0.9% sodium chloride solution, and the model group mice were intraperitoneally injected with 0.1 ml of 0.9% sodium chloride solution. The JWH133 intervention group mice were intraperitoneally injected with 0.1 ml of JWH133 (2.5 mg/kg, dissolved in physiological saline), and the JWH133+AM630 antagonistic group mice were intraperitoneally injected with 0.1 ml of JWH133 (2.5 mg/kg) and AM630 (2.5 mg/kg). After 28 days, all mice were killed; the lung tissue was obtained, pathological changes were observed, and alveolar inflammation scores and Ashcroft scores were calculated. The content of type Ⅰ collagen in the lung tissue of the four groups of mice was measured using immunohistochemistry. The levels of interleukin 6 (IL-6) and tumor necrosis factor α (TNF-α) in the serum of the four groups of mice were measured using enzyme-linked immunosorbent assay (ELISA), and the content of hydroxyproline (HYP) in the lung tissue of the four groups of mice was measured. Western blotting was used to measure the protein expression levels of type Ⅲ collagen, α-smooth muscle actin (α-SMA), extracellular signal regulated kinase (ERK1/2), phosphorylated P-ERK1/2 (P-ERK1/2), and phosphorylated ribosome S6 kinase type 1 (P-p90RSK) in the lung tissue of mice in the four groups. Real-time quantitative polymerase chain reaction was used to measure the expression levels of collagen Ⅰ, collagen Ⅲ, and α-SMA mRNA in the lung tissue of the four groups of mice. Results: Compared with the control group, the pathological changes in the lung tissue of the model group mice worsened, with an increase in alveolar inflammation score (3.833±0.408 vs. 0.833±0.408, P<0.05), an increase in Ashcroft score (7.333±0.516 vs. 2.000±0.633, P<0.05), an increase in type Ⅰ collagen absorbance value (0.065±0.008 vs. 0.018±0.006, P<0.05), an increase in inflammatory cell infiltration, and an increase in hydroxyproline levels [(1.551±0.051) μg/mg vs. (0.974±0.060) μg/mg, P<0.05]. Compared with the model group, the JWH133 intervention group showed reduced pathological changes in lung tissue, decreased alveolar inflammation score (1.833±0.408, P<0.05), decreased Ashcroft score (4.167±0.753, P<0.05), decreased type Ⅰ collagen absorbance value (0.032±0.004, P<0.05), reduced inflammatory cell infiltration, and decreased hydroxyproline levels [(1.148±0.055) μg/mg, P<0.05]. Compared with the JWH133 intervention group, the JWH133+AM630 antagonistic group showed more severe pathological changes in the lung tissue of mice, increased alveolar inflammation score and Ashcroft score, increased type Ⅰ collagen absorbance value, increased inflammatory cell infiltration, and increased hydroxyproline levels. Compared with the control group, the expression of α-SMA, type Ⅲ collagen, P-ERK1/2, and P-p90RSK proteins in the lung tissue of the model group mice increased, while the expression of type Ⅰ collagen, type Ⅲ collagen, and α-SMA mRNA increased. Compared with the model group, the protein expression of α-SMA (relative expression 0.60±0.17 vs. 1.34±0.19, P<0.05), type Ⅲ collagen (relative expression 0.52±0.09 vs. 1.35±0.14, P<0.05), P-ERK1/2 (relative expression 0.32±0.11 vs. 1.14±0.14, P<0.05), and P-p90RSK (relative expression 0.43±0.14 vs. 1.15±0.07, P<0.05) decreased in the JWH133 intervention group. The type Ⅰ collagen mRNA (2.190±0.362 vs. 5.078±0.792, P<0.05), type Ⅲ collagen mRNA (1.750±0.290 vs. 4.935±0.456, P<0.05), and α-SMA mRNA (1.588±0.060 vs. 5.192±0.506, P<0.05) decreased. Compared with the JWH133 intervention group, the JWH133+AM630 antagonistic group increased the expression of α-SMA, type Ⅲ collagen, P-ERK1/2, and P-p90RSK protein in the lung tissue of mice, and increased the expression of type Ⅲ collagen and α-SMA mRNA. Conclusion: In mice with bleomycin-induced pulmonary fibrosis, the cannabinoid type-2 receptor agonist JWH133 inhibited inflammation and improved extracellular matrix deposition, which alleviated lung fibrosis. The underlying mechanism of action may be related to the activation of the ERK1/2-RSK1 signaling pathway.
Mice ; Male ; Animals ; Pulmonary Fibrosis/pathology* ; Cannabinoid Receptor Agonists/metabolism* ; Collagen Type I/pharmacology* ; Collagen Type III/pharmacology* ; Hydroxyproline/pharmacology* ; Sodium Chloride/metabolism* ; Mice, Inbred C57BL ; Lung/pathology* ; Cannabinoids/adverse effects* ; Bleomycin/metabolism* ; Collagen/metabolism* ; Inflammation/pathology* ; RNA, Messenger/metabolism*

To investigate the therapeutic effect and mechanism of Qingfei oral liquid in idiopathic pulmonary fibrosis. Seventy-two male SD rats were divided into control group, model group, pirofenidone group and Qingfei group with 18 animals in each group. The idiopathic pulmonary fibrosis was induced in last three groups by intratracheal injection of bleomycin; pirofenidone group was given oral administration of pirofenidone b.i.d for 21 d, and Qingfei group was given Qingfei oral liquid 3.6 mL/kg q.d for Lung tissues were obtained for HE staining, Masson staining and transforming growth factor (TGF)-β immunohistochemical staining. Superoxide dismutase (SOD), malondialdehyde (MDA) and glutathione (GSH) were detected in tissue homogenates. The BATMAN-TCM database was used to retrieve the chemical components and their corresponding targets of Qingfei oral solution by network pharmacology method, and then the component-target-disease network diagram was constructed. Finally, the pathway enrichment analysis was carried out to explore the molecular mechanism of Qingfei oral liquid against idiopathic fibrosis. Histopathology results showed that Qingfei oral liquid had a similar relieving effect on pulmonary fibrosis as the positive drug pirfenidone; TGF-β secretion had a significant reduction in lung tissues of Qingfei group; and Qingfei oral liquid had better regulatory effect on SOD, MDA and GSH than pirfenidone. The results of component-target-disease network and pathway enrichment analysis showed that the related molecular pathways were concentrated in inflammation, extracellular matrix and cytokines. Qingfei oral liquid has a good therapeutic effect on idiopathic pulmonary fibrosis in rats via regulation of inflammation, extracellular matrix and cytokines.
Animals ; Bleomycin/pharmacology* ; Cytokines ; Drugs, Chinese Herbal ; Glutathione ; Idiopathic Pulmonary Fibrosis/drug therapy* ; Inflammation ; Lung/pathology* ; Male ; Network Pharmacology ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase/metabolism* ; Transforming Growth Factor beta/pharmacology*

OBJECTIVE: To develop a convenient method for rapid purification of fresh Pheretima proteins and assess the inhibitory effect of these proteins against pulmonary fibrosis. METHODS: The crude extract of fresh Pheretima was obtained by freeze-drying method and then purified by size exclusion chromatography. The composition of the purified proteins was analyzed by mass spectrometry. MRC-5 cells were treated with 5 ng/mL TGF-β1 alone (model group) or in combination with SB431542 (2 μmol/L) or the purified proteins (13.125 μg/mL), and the cytotoxicity of purified proteins and their inhibitory effects on cell proliferation were detected with CCK8 assay. Flow cytometry was used to detect the changes in cell apoptosis, and the cellular expressions of α-SMA, Vimentin, E-cadherin, collagen I, Smad2/3 and P-Smad2/3 were detected using RT-PCR and Western blotting. In the animal experiment, adult male C57BL/6 mice were subjected to intratracheal instillation of bleomycin followed by treatment with the purified proteins (5 mg/mL) for 21 days, after which HE and Masson staining was used to observe the pathological changes in the lung tissue of the mice. RESULTS: We successfully obtained purified proteins from fresh Pheretima protein by size exclusion chromatography. Treatment with the purified proteins significantly inhibited TGF-β1-induced proliferation of MRC-5 cells (P < 0.01), reduced the cellular expressions of α-SMA, Vimentin and collagen I (P < 0.001 or P < 0.01), increased the expression of E-cadherin (P < 0.01), and inhibited the expressions of Smad2/3 and P-Smad2/3 (P < 0.001 or P < 0.01). In male C57BL/6 mice models of bleomycin-induced pulmonary fibrosis, treatment with the purified proteins obviously reduced the number of inflammatory cells and fibrotic area in the lungs. CONCLUSION The purified proteins from fresh Pheretima obtained by size exclusion chromatography can inhibit pulmonary fibrosis in mice by regulating the TGF-β/ Smad pathway.
Animals ; Biological Products/pharmacology* ; Bleomycin/adverse effects* ; Cadherins/metabolism* ; Collagen Type I ; Lung/pathology* ; Male ; Mice ; Mice, Inbred C57BL ; Oligochaeta/chemistry* ; Pulmonary Fibrosis/drug therapy* ; Transforming Growth Factor beta1/metabolism* ; Vimentin/metabolism*

OBJECTIVE: To study the preventive and therapeutic effects of safflower water extract on systemic scleroderma (SSc) in mice and its mechanism. METHODS: Sixty BALB/C mice were randomly divided into the control group, model group, prednisone group and safflower low, middle, high dose groups, 10 mice in each group.The control group was injected with normal saline, and the other five groups were subcutaneously injected with bleomycin hydrochloride with 100 μl at the concentration of 200 μg /ml on the back, once a day for 28 days to establish the SSc models.At the same time, the control group and model group were treated with normal saline (10 ml/kg), the prednisone group was treated with prednisone 4.5 mg/kg (10 ml/kg), and the low, middle, and high dose safflower groups were treated with safflower at the doses of 1.5, 3, 6 g/kg (10 ml/kg), and all groups were treated for 28 days.After 28 days, all mice were decapitated. The blood samples and back skin of the BLM injection part were collected.After that, all the tissue slices were taken to measure the dermal thickness, and the content of hydroxyproline (HYP) in the skin tissues was detected by hydrolysis method.The contents of tissue growth factor (CTGF) and transforming growth factor-β (TGF-β ) in the skin tissues and the levels of interleukin-6 (IL-6) and interleukin-17 (IL-17) in serum were determined by ELISA. RESULTS: Compared with the control group, the dermal thickness of the model group was increased(P＜0.05), the contents of CTGF, TGF-β and HYP in the skin tissues and the levels of IL-6 and IL-17 in the serum of the model group were increased(P＜0.05); compared with the model group, the dermal thickness in the prednisone group and safflower groups was decreased (P＜0.05), the levels of CTGF, TGF-β and HYP in the skin tissues and the serum levels of IL-6 and IL-17 in the prednisone group and safflower groups were decreased (P＜0.05). CONCLUSION Safflower water extract can improve skin condition (or dermal thickness) in SSc mice, and its mechanism may be related to reducing immune inflammatory response.
Animals ; Bleomycin ; Carthamus tinctorius ; chemistry ; Connective Tissue Growth Factor ; metabolism ; Disease Models, Animal ; Hydroxyproline ; analysis ; Interleukin-17 ; metabolism ; Interleukin-6 ; metabolism ; Mice ; Mice, Inbred BALB C ; Plant Extracts ; pharmacology ; Random Allocation ; Scleroderma, Systemic ; drug therapy ; Skin ; pathology ; Transforming Growth Factor beta1 ; metabolism

OBJECTIVE: To investigate the effects of Yiqi Huayu Hutan decoction on pulmonary fibrosis of rats which induced by bleomycin. METHODS: The rat model of pulmonary fibrosis was induced by intratracheal injection of bleomycin hydrochloride (5 mg/kg). Sixty SD rats were randomly divided into the normal group (group N), the model group (group M), the positive control group (group Y), group of low concentration (group LC), group of medium concentration (group MC) and group of high concentration of Yiqi Huayu Hutan decoction (group HC). After 4 weeks, the experimental groups were treated with low concentration decoction, medium concentration decoction and high concentration decoction respectively, and the Y group was treated with hydrocortisone acetate, the Group N and group M were treated with saline by intragastric administration. Twelve weeks later, rats were killed and the pathomorphism of pulmonary tissues of each group was observed by HE staining and Masson staining. Further, the expressions of transforming growth factor-β1(TGF-β1), Snail1, E-cadherin and Fibronectin in pulmonary tissues of each group were detected by qTR-PCR and Western blot. RESULTS: Compared with the model group, the collagen sediment in the interstitial was reduced in the experimental groups, especially in the group of medium concentration, which was observed by HE staining and Masson staining .Compared with the model group, the expressions of TGF-β1, Snail1 and Fibronectin protein in pulmonary tissues of the treatment groups were decreased in the experimental group, especially in the group of medium concentration, which were detected by qRT-PCR and Western blot. CONCLUSION Yiqi Huayu Hutan decoction can significantly improve the pulmonary fibrosis which is induced by bleomycin, and the mechanism is related to the inhibition of the expression of TGF-β/Snail pathway of transcription TGF-β1.
Animals ; Bleomycin ; Cadherins ; metabolism ; Drugs, Chinese Herbal ; pharmacology ; Fibronectins ; metabolism ; Idiopathic Pulmonary Fibrosis ; chemically induced ; drug therapy ; Lung ; metabolism ; pathology ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Snail Family Transcription Factors ; metabolism ; Transforming Growth Factor beta1 ; metabolism

BACKGROUNDIdiopathic pulmonary fibrosis (IPF) is the most common and devastating form of interstitial lung disease (ILD) in the clinic. There is no effective therapy except for lung transplantation. Rapamycin is an immunosuppressive drug with potent antifibrotic activity. The purpose of this study was to examine the effects of rapamycin on bleomycin-induced pulmonary fibrosis in rats and the relation to the expression of metalloproteinase-9 (MMP-9) and tissue inhibitor of metalloproteinase-1 (TIMP-1).

METHODSSprague-Dawley rats were treated with intratracheal injection of 0.3 ml of bleomycin (5 mg/kg) in sterile 0.9% saline to make the pulmonary fibrosis model. Rapamycin was given at a dose of 0.5 mg/kg per gavage, beginning one day before bleomycin instillation and once daily until animal sacrifice. Ten rats in each group were sacrificed at 3, 7, 14, 28 and 56 days after bleomycin administration. Alveolitis and pulmonary fibrosis were semi-quantitatively assessed after HE staining and Masson staining under an Olympus BX40 microscope with an IDA-2000 Image Analysis System. Type I and III collagen fibers were identified by Picro-sirius-polarization. Hydroxyproline content in lung tissue was quantified by a colorimetric-based spectrophotometric assay, MMP-9 and TIMP-1 were detected by immunohistochemistry and by realtime quantitative reverse transcriptase polymerase chain reaction (RT-PCR).

RESULTSBleomycin induced alveolitis and pulmonary fibrosis of rats was inhibited by rapamycin. Significant inhibition of alveolitis and hydroxyproline product were demonstrated when daily administration of rapamycin lasted for at least 14 days. The inhibitory efficacy on pulmonary fibrosis was unremarkable until rapamycin treatment lasted for at least 28 days (P < 0.05). It was also demonstrated that rapamycin treatment reduced the expression of MMP-9 and TIMP-1 in lung tissue that was increased by bleomycin.

CONCLUSIONThese results highlight the significance of rapamycin in alleviating alveolitis and pulmonary fibrosis, which is associated with decreased expression of MMP-9 and TIMP-1.

Animals ; Bleomycin ; pharmacology ; Lung ; drug effects ; metabolism ; Male ; Matrix Metalloproteinase 9 ; metabolism ; Pulmonary Fibrosis ; chemically induced ; drug therapy ; Rats ; Rats, Sprague-Dawley ; Sirolimus ; therapeutic use ; Tissue Inhibitor of Metalloproteinase-1 ; metabolism

Pingyangmycin (bleomycin A5 hydrochloride, PYM) is one of the anti-neoplastic agents which have been commonly used to treat venous malformations. However, the underlying mechanism by which PYM treats venous malformations remains poorly understood. It was reported that venous endothelial cells could recruit neutrophils via adhesion molecules (E-selectin, ICAM-1, ICAM-3, VCAM-1) during the acute/chronic inflammation and subsequent histological fibrosis after sclerotherapy with PYM. This study explored if the expression of E-selectin, ICAM-1, ICAM-3 and VCAM-1 in human venous malformation endothelial cells could be affected by PYM. HVMECs were cultured from human venous malformation tissue. Expressions of E-selectin, ICAM-1, ICAM-3 and VCAM-1 on HVMECs in response to PYM were analyzed by cell ELISA. The relative levels of mRNA expression in the cells were semi-quantified. The results showed that PYM up-regulated the expressions of E-selectin, ICAM-3, VCAM-1 and ICAM-1 in both time- and concentration-dependent manner. Our findings suggested that PYM could induce the expression of adhesion molecules in HVMECs, which might be a possible mechanism by which sclerotherapy by intralesional injection of PYM treats venous malformations.
Bleomycin ; analogs & derivatives ; pharmacology ; Cell Adhesion Molecules ; genetics ; metabolism ; Cells, Cultured ; Endothelial Cells ; drug effects ; metabolism ; Endothelium, Vascular ; drug effects ; metabolism ; Gene Expression ; drug effects ; genetics ; Humans