This study is to determine the preventive effect and mechanism of targeting IL-17A on pulmonary inflammation and fibrosis after acute lung injury. Mice were treated with anti-IL-17A antibody on the day 7 and sacrificed on the day 14 after bleomycin lung injury. The pulmonary inflammatory status and the deposition of collagen were measured by HE and Sirius stains staining. The contents of hydroxyproline and collagen were measured by using commercial kits. The survival rate of mice was calculated by Kaplan-Meier methods. The inflammatory cytokines in bronchoalveolar lavage fluid were measured by ELISA and the expressions of inflammation-related molecules were detected by Western blotting assay. Targeting of IL-17A could prevent the development of lung inflammation, decrease collagen deposition and the contents of hydroxyproline, and protect against the development of pulmonary fibrosis, which together led to an increase in the animal survival. Moreover, blocking IL-17A decreased the expression ofpro-fibrotic cytokines such as IL-17A, TGF-beta1 and IL-13; increased the expression of anti-fibrotic or anti-inflammatory factors such as IFN-gamma, COX-2, 5-LOX, 15-LOX. Indeed, IL-17A antagonism suppressed the activation of pro-inflammatory p65NF-kappaB but enhanced the activation of pro-resolving p50NF-kappaB. In conclusion, that blockade of IL-17A prevents the development of pulmonary fibrosis from acute lung injury, is because blocking IL-17A may prevent acute inflammation converting to chronic inflammation.
Acute Lung Injury ; chemically induced ; complications ; Animals ; Bleomycin ; Collagen ; metabolism ; Hydroxyproline ; metabolism ; Interleukin-13 ; metabolism ; Interleukin-17 ; antagonists & inhibitors ; metabolism ; Male ; Mice ; Mice, Inbred C57BL ; NF-kappa B p50 Subunit ; metabolism ; Pneumonia ; etiology ; metabolism ; Pulmonary Fibrosis ; etiology ; metabolism ; prevention & control ; Random Allocation ; Transcription Factor RelA ; metabolism ; Transforming Growth Factor beta1 ; metabolism ; Up-Regulation

OBJECTIVETo investigate the therapeutic effect of C-phycocyanin (C-PC) from Spirulina platensis on paraquat (PQ)-induced pulmonary fibrosis in rats.

METHODSA total of 90 healthy Wistar rats were randomly and equally divided into normal control group, model group (PQ group), and C-PC treatment group (C-PC group). Each rat in the PQ group and C-PC group were orally administered with a single dose of PQ (50 mg/kg) to establish a rat model of PQ poisoning. Then, the rats in the normal control group and PQ group were orally given saline solution (1 ml/100 g) every day, and the rats in the C-PC group were orally given C-PC (50 mg/kg) every day. Six rats were randomly selected from each group on days 1, 3, 7, 14, and 28. The inferior lobe of each rat's right lung was homogenized for the measurement of hydroxyproline (HYP) and maleic dialdehyde (MDA) levels and superoxide dismutase (SOD) activity. Parts of each rat's left lung were subject to HE staining and Masson staining for pathological observation, and the expression of transforming growth factor-β(1) (TGF-β(1)), nuclear factor-kappa B p65 (NF-κB p65), and tumor necrosis factor-α (TNF-α) in lung tissue was measured by immunohistochemistry.

RESULTSThe HYP levels on days 1, 3, 7, 14, and 28 and MDA levels on days 14 and 28 were significantly lower in the C-PC group than in the PQ group (P < 0.05, P < 0.01). The SOD activity was significantly higher in the C-PC group than in the PQ group on days 1, 7, 14, and 28 (P < 0.05, P < 0.01). The protein content of TGF-β(1) and the activities of NF-κB p65 and TNF-α in the PQ group and C-PC group were significantly higher than those in the normal control group, while the indices in the C-PC group were significantly lower than those in the PQ group (P < 0.05, P < 0.01). The pathological observation showed that C-PC could alleviate pulmonary alveolitis and fibrosis in rats with PQ poisoning.

CONCLUSIONC-PC can significantly inhibit PQ-induced pulmonary alveolitis and fibrosis in rats.

Animals ; Lung ; metabolism ; pathology ; Male ; NF-kappa B ; metabolism ; Paraquat ; poisoning ; Phycocyanin ; pharmacology ; Pulmonary Fibrosis ; chemically induced ; metabolism ; prevention & control ; Rats ; Rats, Wistar ; Transcription Factor RelA ; metabolism ; Transforming Growth Factor beta ; metabolism ; Tumor Necrosis Factor-alpha ; metabolism

OBJECTIVETo compare the difference of effects on SiO(2)-induced alveolitis and early fibrosis between bone marrow-derived mesenchymal-like stem cells (BM-MSCs) and BM-MSCs transfected by pcDNA3.1-HGF and to explore the mechanism of this effects.

METHODSThe Primary BM-MSCs from Wistar male young rats were cultured and labeled by 4, 6-diamidino-2-phenylindole (DAPI). Fifty Wistar rats were randomly divided into 3 groups:model group (10 rats),which was administered with SiO(2) by the trache, the next day,injected PBS via the tail vein; BM-MSCs group (20 rats),which was administered with SiO(2) by the trache, the next day,injected with 1 ml suspension of BM-MSCs via the tail vein; pcDNA3.1-HGF plus BM-MSC group (20 rats),which was administered with SiO(2) by the trache, the next day,injected with 1 ml suspension of BM-MSCs transfected by pcDNA3.1-HGF via the tail vein. On the 14th and 28th days after treatment, half of the animals were sacrificed, respectively, and the lungs were harvested for frozen section to observe the cell marked by DAPI. HE staining under a fluorescent microscope, and to observe the pulmonary alveolitis and fibrosis by HE and Masson staining under a light microscope. Western blot assay was used to detect the expression of HGF in rat lungs. The expression levels of tumor necrosis factor-α (TNF-α) in pulmonary tissues were analyzed quantitatively by ELISA. The contents of HYP in pulmonary tissues were analyzed quantitatively by sample hydrolysis method.

RESULTSOn the 14th and 28th days after treatment, the scores of pulmonary alveolitis and early fibrosis in pcDNA3.1-HGF plus BM-MSCs group were 2.36 ± 0.17, 2.8 ± 0.14 and 0.1 ± 0.11, 1.16 ± 0.13, which were significantly lower than those (1.68 ± 0.17, 1.58 ± 0.31 and 0.54 ± 0.15, 1.36 ± 0.13) in BM-MSCs group, also which were significantly lower those (2.36 ± 0.17, 2.80 ± 0.14 and 0.64 ± 0.09, 1.84 ± 0.17) in model group (P < 0.05); On the 14th and 28th days after treatment, the TNF-α contents of pulmonary tissues in pcDNA3.1-HGF plus BM-MSCs group were 280.4 ± 23.11 and 249.78 ± 22.33 pg/mg, which were significantly lower than those (341.58 ± 35.34, 442.29 ± 36.76 pg/mg and 319.51 ± 17.84, 348.53 ± 33.95 pg/mg) in BM-MSCs and model groups (P < 0.05); On the 14th and 28th days after treatment, the HYP contents of pulmonary tissues in pcDNA3.1-HGF plus BM-MSCs group were 0.46 ± 0.04 and 0.65 ± 0.05 µg/mg, which were significantly lower than those (0.63 ± 0.04, 1.04 ± 0.07 µg/mg and 0.72 ± 0.60, 1.39 ± 0.60 µg/mg) in BM-MSCs and model groups (P < 0.05).

CONCLUSIONThe effects of BM-MSCs transfected by pcDNA3.1-HGF on suppressing pulmonary alveolitis and early fibrosis induced by SiO2 were better than those of BM-MSCs. The mechanism may be associated with the reduced pulmonary inflammation.

Animals ; Bone Marrow Cells ; cytology ; Hepatocyte Growth Factor ; genetics ; metabolism ; Male ; Mesenchymal Stromal Cells ; metabolism ; Pulmonary Fibrosis ; chemically induced ; prevention & control ; Rats ; Rats, Wistar ; Silicon Dioxide ; toxicity ; Silicosis ; prevention & control ; Transfection

CXC chemokine receptor 4 (CXCR4), which binds the stromal cell-derived factor-1 (SDF-1), has been shown to play a critical role in mobilizing the bone marrow (BM)-derived stem cells and inflammatory cells. We studied the effects of AMD3100, CXCR4 antagonist, on a murine bleomycin-induced pulmonary fibrosis model. Treatment of mice with AMD3100 in bleomycin-treated mice resulted in the decrease of SDF-1 in bronchoalveolar lavage (BAL) fluids at an early stage and was followed by the decrease of fibrocytes in the lung. AMD3100 treatment decreased the SDF-1 mRNA expression, fibrocyte numbers in the lung at an early stage (day 3) and CXCR4 expression at the later stage (day 7 and 21) after bleomycin injury. The collagen content and pulmonary fibrosis were significantly attenuated by AMD3100 treatment in later stage of bleomycin injury. AMD3100 treatment also decreased the murine mesenchymal and hematopoietic stem cell chemotaxis when either in the stimulation with bleomycin treated lung lysates or SDF-1 in vitro. In BM stem cell experiments, the phosphorylation of p38 MAPK which was induced by SDF-1 was significantly blocked by addition of AMD3100. Our data suggest that AMD3100 might be effective in preventing the pulmonary fibrosis by inhibiting the fibrocyte mobilization to the injured lung via blocking the SDF-1/CXCR4 axis.
Animals ; *Bleomycin ; Bronchoalveolar Lavage Fluid/chemistry ; Cell Movement/drug effects ; Cells, Cultured ; Chemokine CXCL12/chemistry/metabolism ; Cytoprotection/drug effects ; Down-Regulation/drug effects ; Drug Evaluation, Preclinical ; Female ; Heterocyclic Compounds/pharmacology/*therapeutic use ; Lung/drug effects/metabolism/pathology ; Mice ; Mice, Inbred C57BL ; Pulmonary Fibrosis/*chemically induced/*prevention & control ; Receptors, CXCR4/*antagonists & inhibitors/metabolism

To clarify the mechanism underlying the preventive effect of baicalin (Bai) on fibrosis in lung, we investigated the influence of Bai on the up-regulation of connective tissue growth factor (CTGF) in fibrotic lungs. Male Sprague-Dawley (SD) rats were divided into four groups randomly: normal saline (NS)+NS group (a single intratracheal instillation of NS plus i.p. injection of NS), NS+Bai group (intratracheal instillation of NS plus i.p. injection of Bai), bleomycin (BLM)+NS group (intratracheal instillation of BLM plus i.p. injection of NS) and BLM+Bai group (intratracheal instillation of BLM plus i.p. injection of Bai). All the i.p. injections were performed once daily. On day 28 after intratracheal instillation of BLM or NS, the rats were sacrificed for lung tissue sampling. As the index of the severity of pulmonary fibrosis, the content of hydroxyproline in lungs was analyzed by chloramine T method. The expression levels of CTGF mRNA and protein in the lungs were detected by RT-PCR and immunohistochemistry, respectively. The results showed that, compared to the rats in NS+NS group, the rats in BLM+NS group showed increased hydroxyproline content and higher levels of CTGF mRNA and protein expressions (P<0.01), suggesting that BLM had induced fibrosis in lung and up-regulated CTGF expression in the fibrotic lungs. Administration of different dosages of Bai (6, 12.5 and 50 mg/kg per d, for 28 days) into the BLM-treated rats reduced the increased content of hydroxyproline, and ameliorated the up-regulation of CTGF mRNA and protein levels, respectively. These results suggest that Bai could prevent the up-regulation of CTGF expression in fibrotic lungs of rats receiving BLM instillation, which might be one of the mechanisms underlying the preventive effect of Bai on pulmonary fibrosis.
Animals ; Bleomycin ; Connective Tissue Growth Factor ; genetics ; metabolism ; Flavonoids ; pharmacology ; therapeutic use ; Hydroxyproline ; metabolism ; Male ; Pulmonary Fibrosis ; chemically induced ; metabolism ; prevention & control ; RNA, Messenger ; genetics ; metabolism ; Rats ; Rats, Sprague-Dawley

AIMTo explore the effects of aminoguanidine (AG) inhalation on bleomycin (BLM)-induced fibrosis in lungs of rats and its possible mechanism.

METHODSSixty male Sprague-Dawley rats were randomly divided into 4 groups: BLM plus normal saline (NS) group, BLM plus 10 mmol/L AG group, BLM plus 50 mmol/L AG group, and NS plus NS group. At the same day when administrated by single intratracheal instillation of BLM (5 mg/kg) or equal volume of NS as control, the rats received NS (the same volume as AG) or AG inhalation (10 mmol/L AG, or 50 mmol/L AG, 5 min/each time, 2/day) for 30 d. The nitrite/nitrate (NO2-/NO3-) content of plasma in pulmonary artery, hydroxyproline content and the pathological changes in lungs, as well as lipid peroxide (LPO) content of plasma in pulmonary artery were examined.

RESULTSThe NO2-/NO3- content of plasma in pulmonary artery was increased in rats on day 14 after intratracheal instillation of BLM, compared with that of the control rats (P < 0.01). The hydroxyproline content in lung, the grade of pulmonary alveolitis and the content of LPO of plasma in pulmonary artery were increased in rats on day 30 after intratracheal instillation of BLM, compared with that of the control rats, respectively (P < 0.05, P < 0.01, P < 0.01). The above-mentioned changes were ameliorated by AG inhalation (10 mmol/L AG, or 50 mmol/ LAG, 5 min/each time, 2/day) for 30 d (P < 0.01, P < 0.05, P < 0.05, P < 0.01).

CONCLUSIONAG inhalation has anti-action on BLM-induced fibrosis in lung, which might be related to blockage of oxidative injury in lung.

Administration, Inhalation ; Animals ; Bleomycin ; Enzyme Inhibitors ; administration & dosage ; pharmacology ; Guanidines ; administration & dosage ; pharmacology ; Male ; Nitric Oxide Synthase ; antagonists & inhibitors ; Oxidative Stress ; drug effects ; Pulmonary Fibrosis ; chemically induced ; physiopathology ; prevention & control ; Rats ; Rats, Sprague-Dawley

OBJECTIVETo study on the effect and mechanism of curcumin on inhibiting injury induced by free radical in pulmonary fibrosis.

METHODOne hundred and forty-four male SD rats were randomly divided into 6 groups (24 rats in each group). Rats in the model control group, positive medicine group, and high, moderate and low curcumin groups were injected with a single dose of bleomycin by trachea, and rats in sham-model control group with same volume normal saline. One day after the injection, curcumin solution of different dosages (200,100,50 mg x kg(-1) x d(-1)) was respectively given to rats in the high, moderate and low curcumin group by daily gastrogavage, while equal volume of normal saline was given to those in the sham-model control group and model control group, and an equal volume of prednisone (0.56 mg x kg(-1) x d(-1)) was saline was given to those in positive medicine control group. On the 7, 14, 28 days, the contents of GSH-Px, SOD, MDA and iNOS in pulmonary tissues of different groups were measured.

RESULTCurcumin can raise the content of SOD and GSH-Px and lessen the level of MDA and iNOS.

CONCLUSIONCurcumin can regulate the level of free radical in the body of rats with pulmonary fibrosis and lessen the oxidative injury of pulmonary tissues caused by free radical, in the body of rats with pulmonary fibrosis. The mechanisms of curcumin on idiopathic pulmonary fibrosis lie in adjusting the level of free radical and inhibiting the injury of lung tissue induced by free radical.

Animals ; Antioxidants ; isolation & purification ; pharmacology ; Bleomycin ; Curcuma ; chemistry ; Curcumin ; isolation & purification ; pharmacology ; Free Radicals ; metabolism ; Glutathione Peroxidase ; metabolism ; Lung ; drug effects ; metabolism ; pathology ; Male ; Malondialdehyde ; metabolism ; Nitric Oxide Synthase Type II ; metabolism ; Plants, Medicinal ; chemistry ; Pulmonary Fibrosis ; chemically induced ; metabolism ; prevention & control ; Random Allocation ; Rats ; Rats, Sprague-Dawley ; Superoxide Dismutase ; metabolism