Retracted: Obestatin Plays Beneficial Role in Cardiomyocyte Injury Induced by Ischemia-Reperfusion In Vivo and In Vitro.

The Editors of Medical Science Monitor wish to inform you that the above manuscript has been retracted from publication due to concerns with the credibility and originality of the study, the manuscript content, and the Figure images. Reference: Qin Zhang, Xin-wei Dong, Jia-ying Xia, Ke-ying Xu, Zhe-rong Xu. Obestatin Plays Beneficial Role in Cardiomyocyte Injury Induced by Ischemia-Reperfusion In Vivo and In Vitro. Med Sci Monit, 2017; 23: 2127-2136. DOI: 10.12659/MSM.901361.

Obestatin Plays Beneficial Role in Cardiomyocyte Injury Induced by Ischemia-Reperfusion In Vivo and In Vitro.

BACKGROUND Obestatin, primarily recognized as a peptide within the gastrointestinal system, has been shown to benefit the cardiovascular system. We designed this experiment to study the protective role and underlying mechanism of obestatin against ischemia-reperfusion(I/R) injury in myocardial cells. MATERIAL AND METHODS In an In vivo experiment, LAD was ligated for 0.5 h and then opened for reperfusion with obestatin for 24 h. Then, the infarction area was shown with TTC staining, and inflammation factors in serum were analyzed by qRT-PCR. In primary cultured cardiomyocytes, we measured the level of LDH, MDA, GSH, and SOD. Finally, we assessed cells apoptosis using flow cytometry and detected the concentrations of caspase-3, Bax, and Bcl-2 using Western blot analysis. RESULTS TTC staining showed that in the 3 obestatin groups, the infarct area became smaller with the increase of obestatin concentration. Obestatin also inhibited LDH expression in rat serum and decreased mRNA levels of TNF-α, IL-6, ICAM-1, and iNOS in rat cardiomyocytes after reperfusion. In primary cultured cardiomyocytes, obestatin decreased LDH content and increased GSH level after I/R injury. Obestatin was also found to antagonize the apoptosis of cardiomyocytes in a dose-dependent manner. Western blot analysis showed that obestatin downregulated the expression of caspase-3 and Bax and upregulated the expression of Bcl-2. CONCLUSIONS Obestatin can protect cardiomyocyte from I/R-induced injury in vitro and in vivo. This beneficial effect is closely related with its properties of anti-inflammation, anti-cytotoxicity, and anti-apoptosis. The protective effect of obestatin might be associated with activation of Bcl-2 and inhibition of caspase-3 and Bax.

Cigarette smoke-induced alveolar epithelial-mesenchymal transition is mediated by Rac1 activation.

BACKGROUND: Epithelial-mesenchymal transition (EMT) is the major pathophysiological process in lung fibrosis observed in chronic obstructive pulmonary disease (COPD) and lung cancer. Smoking is a risk factor for developing EMT, yet the mechanism remains largely unknown. In this study, we investigated the role of Rac1 in cigarette smoke (CS) induced EMT. METHODS: EMT was induced in mice and pulmonary epithelial cells by exposure of CS and cigarette smoke extract (CSE) respectively. RESULTS: Treatment of pulmonary epithelial cells with CSE elevated Rac1 expression associated with increased TGF-ß1 release. Blocking TGF-ß pathway restrained CSE-induced changes in EMT-related markers. Pharmacological inhibition or knockdown of Rac1 decreased the CSE exposure induced TGF-ß1 release and ameliorated CSE-induced EMT. In CS-exposed mice, pharmacological inhibition of Rac1 reduced TGF-ß1 release and prevented aberrations in expression of EMT markers, suggesting that Rac1 is a critical signaling molecule for induction of CS-stimulated EMT. Furthermore, Rac1 inhibition or knockdown abrogated CSE-induced Smad2 and Akt (PKB, protein kinase B) activation in pulmonary epithelial cells. Inhibition of Smad2, PI3K (phosphatidylinositol 3-kinase) or Akt suppressed CSE-induced changes in epithelial and mesenchymal marker expression. CONCLUSIONS AND GENERAL SIGNIFICANCE: Altogether, these data suggest that CS initiates EMT through Rac1/Smad2 and Rac1/PI3K/Akt signaling pathway. Our data provide new insights into the fundamental basis of EMT and suggest a possible new course of therapy for COPD and lung cancer.

AD-1, a novel ginsenoside derivative, shows anti-lung cancer activity via activation of p38 MAPK pathway and generation of reactive oxygen species.

BACKGROUND: Ginseng is a traditional Chinese herb that has been used for thousands of years. In the present study, effects and mechanisms of AD-1 were evaluated for its development as a novel anti-lung cancer drug. METHODS: The cytotoxic activity was evaluated by MTT assay. Flow cytometry was employed to detect cell cycle, apoptosis and ROS. Western blot and immunohistochemistry were used to analyze signaling pathways. Lung cancer xenograft models were established by subcutaneous implantation of A549 or H292 cells into nude mice. RESULTS: AD-1 concentration-dependently reduces lung cancer cell viability without affecting normal human lung epithelial cell viability. In A549 and H292 lung cancer cells, AD-1 induces G0/G1 cell cycle arrest, apoptosis and ROS production. The apoptosis can be attenuated by a ROS scavenger - N-acetylcysteine (NAC). In addition, AD-1 up-regulates the expression of p38 and ERK phosphorylation. Addition of a p38 inhibitor SB203580, suppresses the AD-1-induced decrease in cell viability. Furthermore, genetic silencing of p38 attenuates the expression of p38 and decreases the AD-1-induced apoptosis. Treatment with NAC reduces AD-1-induced p38 phosphorylation, which indicates that ROS generation is involved in the AD-1-induced p38 activation. In mice, oral administration of AD-1 (10-40mg/kg) dose-dependently inhibited the growth of xenograft tumors without affecting body weight and decreases the expression of VEGF, MMP-9 and CD34 in tumor tissue. TUNEL staining confirms that the tumors from AD-1 treated mice exhibit a markedly higher apoptotic index. CONCLUSIONS AND GENERAL SIGNIFICANCE: These data support development of AD-1 as a potential agent for lung cancer therapy.

Shp2 plays an important role in acute cigarette smoke-mediated lung inflammation.

Cigarette smoke (CS), the major cause of chronic obstructive pulmonary disease, contains a variety of oxidative components that were implicated in the regulation of Src homology domain 2-containing protein tyrosine phosphatase 2 (Shp2) activity. However, the contribution of Shp2 enzyme to chronic obstructive pulmonary disease pathogenesis remains unclear. We investigated the role of Shp2 enzyme in blockading CS-induced pulmonary inflammation. Shp2 levels were assessed in vivo and in vitro. Mice (C57BL/6) or pulmonary epithelial cells (NCI-H292) were exposed to CS or cigarette smoke extract (CSE) to induce acute injury and inflammation. Lungs of smoking mice showed increased levels of Shp2, compared with those of controls. Treatment of lung epithelial cells with CSE showed elevated levels of Shp2 associated with the increased release of IL-8. Selective inhibition or knockdown of Shp2 resulted in decreased IL-8 release in response to CSE treatment in pulmonary epithelial cells. In comparison with CS-exposed wild-type mice, selective inhibition or conditional knockout of Shp2 in lung epithelia reduced IL-8 release and pulmonary inflammation in CS-exposed mice. In vitro biochemical data correlate CSE-mediated IL-8 release with Shp2-regulated epidermal growth factor receptor/Grb-2-associated binders/MAPK signaling. Our data suggest an important role for Shp2 in the pathological alteration associated with CS-mediated inflammation. Shp2 may be a potential target for therapeutic intervention for inflammation in CS-induced pulmonary diseases.

Inorganic-Organic Hybrid Molecular Materials: From Multiferroic to Magnetoelectric.

Inorganic-organic hybrid molecular multiferroic and magnetoelectric materials, similar to multiferroic oxide compounds, have recently attracted increasing attention because they exhibit diverse architectures, a flexible framework, fascinating physics, and potential magnetoelectric functionalities in novel multifunctional devices such as energy transformation devices, sensors, and information storage systems. Herein, the classification of multiferroicity and magnetoelectricity is briefly outlined and then the recent advances in the multiferroicity and magnetoelectricity of inorganic-organic hybrid molecular materials, particularly magnetoelectricity and the relevant magnetoelectric mechanisms and their categories are summarized. In addition, a personal perspective and an outlook are provided.

Leukotriene B4, administered via intracerebroventricular injection, attenuates the antigen-induced asthmatic response in sensitized guinea pigs.

BACKGROUND: Despite intensive studies focused on the pathophysiology of asthmatic inflammation, little is known about how cross-talk between neuroendocrine and immune systems regulates the inflammatory response during an asthmatic attack. We recently showed corresponding changes of cytokines and leukotriene B4 (LTB4) in brain and lung tissues of antigen-challenged asthmatic rats. Here, we investigated how LTB4 interacts with the neuroendocrine-immune system in regulating antigen-induced asthmatic responses in sensitized guinea pigs. METHODS: Ovalbumin-sensitized guinea pigs were challenged by inhalation of antigen. Vehicle, LTB4 or U75302 (a selective LTB4 BLT1 receptor inhibitor) was given via intracerebroventricular injection (i.c.v.) 30 min before challenge. Airway contraction response was evaluated using Penh values before and after antigen challenge. The inflammatory response in lung tissue was evaluated 24 h after challenge. The LTB4 content of lung and brain homogenate preparations was detected by reversed phase high-performance liquid chromatography (RP-HPLC). Plasma levels of adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were measured using ELISA kits. RESULTS: Antigen challenge impaired pulmonary function and increased inflammatory cell infiltration in lung tissue. These responses could be significantly suppressed by LTB4, 30 ng i.c.v., in ovalbumin-sensitized guinea pigs. LTB4 content of lung and brain homogenates from antigen-challenged guinea pigs was significantly increased. In addition, administration of LTB4 via i.c.v. markedly increased CORT and ACTH level in plasma before antigen challenge, and there were further increases in CORT and ACTH levels in plasma after antigen challenge. U75302, 100 ng i.c.v., completely blocked the effects of LTB4. In addition, U75302, 100 ng via i.c.v. injection, markedly decreased LTB4 content in lung homogenates, but not in brain homogenates. CONCLUSIONS: Increased LTB4 levels in brain during asthmatic attacks down-regulates airway contraction response and inflammation through the BLT1 receptor. Stimulation of the hypothalamic-pituitary-adrenal axis by LTB4 may result in an increase in systemic glucocorticoids which, in turn, would feed back to suppress the asthmatic response.

Intracerebroventricular injection of leukotriene B4 attenuates antigen-induced asthmatic response via BLT1 receptor stimulating HPA-axis in sensitized rats.

BACKGROUND: Basic and clinical studies suggest that hypothalamic-pituitary-adrenal (HPA) axis is the neuroendocrine-immune pathway that functionally regulates the chronic inflammatory disease including asthma. Our previous studies showed corresponding changes of cytokines and leukotriene B4 (LTB4) between brain and lung tissues in antigen-challenged asthmatic rats. Here, we investigated how the increased LTB4 level in brain interacts with HPA axis in regulating antigen-induced asthmatic response in sensitized rats. METHODS: Ovalbumin-sensitized rats were challenged by inhalation of antigen. Rats received vehicle, LTB4 or U75302 (a selective LTB4 BLT1 receptor inhibitor) was given via intracerebroventricular injection (i.c.v) 30 min before challenge. Lung resistance (RL) and dynamic lung compliance (Cdyn) were measured before and after antigen challenge. Inflammatory response in lung tissue was assessed 24 h after challenge. Expression of CRH mRNA and protein in hypothalamus were evaluated by RT-PCR and Western Blot, and plasma levels of adrenocorticotropic hormone (ACTH) and corticosterone (CORT) were measured using the ELISA kits. RESULTS: Antigen challenge decreased pulmonary function and induced airway inflammation, evoked HPA axis response in sensitized rats. Administration of LTB4 via i.c.v markedly attenuated airway contraction and inflammation. Meanwhile, LTB4 via i.c.v markedly increased CORT and ACTH level in plasma before antigen challenge, and followed by further increases in CORT and ACTH levels in plasma after antigen challenge in sensitized rats. Expression of CRH mRNA and protein in hypothalamus were also significantly increased by LTB4 via i.c.v in sensitized rats after antigen challenge. These effect were completely blocked by pre-treatment with BLT1 receptor antagonist U75302 (10 ng), but not by BLT2 antagonist LY255283. CONCLUSIONS: LTB4 administered via i.c.v down-regulates the airway contraction response and inflammation through activation of the HPA axis via its BLT1 receptor. This study expands our concept of the regulatory role of intracranial inflammatory mediators in inflammatory diseases including asthma. The favourable effects of LTB4 on the HPA axis may help to explain the phenomenon of self-relief after an asthmatic attack.

Anti-allergic activities of 5,7-dimethoxy-3,4'-dihydroxyflavone via inhalation in rat allergic models.

Various studies have shown that flavones have several pharmacological activities including anti-allergy activities. However, the bioavailability of oral flavones is very low, and whether inhaled administration can improve efficacy in respiratory disease models is unclear. In the present study, the anti-allergic activities of inhaling 5,7-dimethoxy-3,4'-dihydroxyflavone (MHF), a synthetic flavonoid, was investigated by comparison with disodium cromoglycate (DSCG) and nedocromil sodium (NS) in rat allergic models. In an anti-DNP-IgE-induced asthmatic model, inhaled MHF dose-dependently inhibited the increase in airway resistance after antigen challenge. In an ovalbumin (OVA)-induced asthmatic model, inhaled MHF showed significant suppression of airway hyperresponsiveness; a decrease in eosinophil and neutrophil counts, IL-4, IL-5 and leukotriene D4 in bronchoalveolar lavage fluid; a reduction in total IgE and OVA-specific IgE levels in serum; and suppression of eosinophil infiltration in lung tissue after antigen challenge. The efficacy of inhaled MHF was comparable to that of NS and DSCG. In conclusion, based on these findings, the report for the first time that that inhaled MHF may be a potential drug for the treatment of allergic asthma.

Oral administration of allergen extracts from Dermatophagoides farinae desensitizes specific allergen-induced inflammation and airway hyperresponsiveness in rats.

Clinically sublingual immunotherapy (SLIT) by using allergen extracts effectively alleviates the symptoms of allergic rhinitis and asthma. Supposed that oral administration of high-dose of allergen extracts imitates SLIT and may prevent IgE-related responses in allergic diseases, we investigated the effects of oral administration of allergen extracts from Dermatophagoides farinae (Derf) on allergen-induced inflammation and airway hyperresponsiveness (AHR) in a model of asthmatic rat. After administration to the specific Derf-sensitized rats with Derfdrop solution containing Derf1 and Derf2 extracts derived from Derf, the effects of Derfdrop on AHR, inflammatory cell accumulation, cytokine production in the bronchoalveolar lavage fluid and lung tissue, as well as serum IgE and IgG levels were investigated. Results indicated that Derfdrop not only dose-dependently prevented the AHR in response to methacholine, but also significantly reduced the serum total and allergen-specific IgE levels, all the maximal effects were achieved at dose of 5 mg/kg/d, and were as comparable as those of dexamethasone at dose of 1.0 mg/kg/d. Furthermore, oral administration of Derfdrop not only dose-dependently elevated allergen-specific serum IgG levels and reduced total and allergen-specific IgE levels, but also normalized the imbalance between the Th1 cytokine, IFN-gamma and Th2 cytokine, IL-4. Finally, oral administration of Derfdrop significantly reduced Goblet cell hyperplasia and eosinophilia in the Derf-sensitized allergic rat model. These data suggest that Derfdrop effectively improves specific allergen-induced inflammation and AHR in Derf-sensitized and -challenged rats and provide with the rationale for clinical SLIT by using Derfdrop in a specific allergen-induced asthma.

[Immunoregulatory effects of pertussis protein on allergic asthma in mouse].

OBJECTIVE: To investigate the immunoregulatory effects of pertussis protein on airway inflammatory, IFN-gamma/IL-4 ratio in bronchoalveolar lavage fluids(BALF) and airway hyperresponsiveness (AHR) in the sensitized mice. METHODS: The sensitized mice were reexposed to ovalbumin and the airway response to methacholine injection was monitored. Inflammatory cells and cytokines IFN-gamma/IL-4 ratio in BALF were measured. Lung tissue specimens were collected for histological examination. RESULT: Intramuscular injection or intranasal instillation of pertussis protein inhibited changes in lung resistance and lung dynamic compliance, upregulated IFN-gamma/IL-4 ratio and decreased eosinophil accumulation in a dose-dependent manner. Pathological examination showed that goblet cell hyperplasia and inflammatory cells infiltration in lung tissue were suppressed by pertussis protein. CONCLUSION: Pertussis protein inhibits the inflammation and regulates the function of lungs in asthma mice, suggesting its potential application in treatment of asthma.

[Inhibitory effects of BIO-1211 on bronchoconstriction and neutrophil adhesion in rats].

OBJECTIVE: To determine the inhibitory effects of BIO-1211, a very late antigen-4 (vla-4) antagonist, on bronchoconstriction and neutrophil adhesion in rats. METHODS: For evaluating ovalbumin-induced bronchoconstriction in the sensitized rats, the changes in lung resistance (RL) and lung dynamic compliance (C(dyn)) were determined after antigen challenge. Neutrophils from the rats were used to determine fibronectin and serum-induced cell adhesion. The effect of BIO-1211 on wheezing was determined after inhalation of histamine and acetylcholine in guinea pigs. RESULT: BIO-1211 aerosol at 1, 3 and 10 mg/ml significantly inhibited the changes in lung resistance and lung dynamic compliance after antigen challenge in the sensitized rats in a dose-dependent manner. BIO-1211 at 25, 50, 100 and 200 microgram/ml inhibited the fibronectin-induced neutrophil adhesion by 23.5%, 24.6%, 61.4% and 58.1%, respectively, and serum-induced adhesion by 29.9%, 35.9%, 35.3% and 15.4%, respectively. Inhalation of 10 mg/ml BIO-1211 did not show any protection against histamine and acetylcholine-induced bronchoconstriction. CONCLUSION: BIO-1211 inhibits bronchoconstriction and neutrophil adhesion, which may be associated with its effect against bronchoconstriction in rats.

Construction of Magnetoelectric Composites with a Large Room-Temperature Magnetoelectric Response through Molecular-Ionic Ferroelectrics.

Magnetoelectric materials with a large magnetoelectric response, a low operating magnetic (or electric) field, and a room-temperature (or higher) operating temperature are of key importance for practical applications. However, such materials are extremely rare because a large magnetoelectric response often requires strong coupling between spins and electric dipoles. Herein, an example of a magnetoelectric composite is prepared by using a room-temperature multiaxial molecular-ionic ferroelectric, tetramethylammonium tetrachlorogallate(III) (1). Investigation of the magnetoelectric effect of the magnetoelectric laminate composite indicates that its room-temperature magnetoelectric voltage coefficient (αME ) is as high as 186 mV cm-1 Oe-1 at HDC = 275 Oe and at the HAC frequency of ≈39 kHz, providing a valid approach for the preparation of magnetoelectric materials and adding a new member to the magnetoelectric material family.

Salvianolic acid B improves airway hyperresponsiveness by inhibiting MUC5AC overproduction associated with Erk1/2/P38 signaling.

Salvianolic acid B (SalB) is one of the main water-soluble composites from Chinese medicine Dansen (Radix miltiorrhiza). It is used for clinical treatment of various diseases including cardiovascular, lung, Liver, renal and cancers. However, the effects of SalB to allergy induced airway mucin hypersecretion, inflammation and hyperresponsiveness (AHR) remains not clear. Overproduction of airway MUC5AC is a central effector of inflammation that is strongly associated with AHR in asthmatic attack. In this study, we investigated the anti-asthmatic activity and mechanism of SalB in a murine model and human epithelial cells by monitoring changes in mucin expression and secretion, airway inflammation, AHR, and signaling pathways. SalB was administered by intragastric administration (i.g) daily for a week, starting at 21 days after sensitization of ovalbumin (OVA). All examinations were performed 24h after the last antigen challenge. We found that treatments with SalB significantly inhibited increase in the tracheobronchial secretion, glycosaminoglycan levels, interleukin (IL)-13, IL-4, and IL-5 cytokines mRNA and protein expression, and decrease in mucociliary clearance in lung tissues. Histological results demonstrated that SalB attenuated OVA-induced eosinophil infiltration, airway goblet cell hyperplasia, and MUC5AC and MUC5B mRNA and protein expression in lung tissues. SalB exhibited protective effects against AHR in OVA-challenged animals. In vitro, SalB significantly inhibited IL-13-induced MUC5AC and MUC5B mRNA and protein expression in human epithelial cells. These effects were blocked by SalB by downregulating the Erk1/2 and P38 signaling pathways. Taken together, these data indicate that treatment with SalB may improve AHR by inhibiting MUC5AC overproduction.

Akt/PKB signaling regulates cigarette smoke-induced pulmonary epithelial-mesenchymal transition.

OBJECTIVES: Cigarette smoke (CS) is a major risk factor for the development of lung cancer and chronic obstructive pulmonary disease (COPD). Epithelial-mesenchymal transition (EMT) is found in invasive or metastatic phenotypes in lung cancer and COPD. MK-2206, a pan Akt inhibitor, has failed in clinical trials for solid tumors when administered alone at tolerated doses, but it has been shown to have synergistic effects when applied with certain molecular targeted agents. In this study, we investigated the working mechanism of MK-2206 in CS-induced pulmonary EMT both in vivo and in vitro. MATERIALS AND METHODS: The expression of Akt, epithelial-mesenchymal transition (EMT) markers and signaling proteins were analyzed by immunohistochemistry, real-time PCR and Western blot in cigarette smoke extract (CSE)-treated pulmonary epithelia and CS-treated lung tissues in mice. RESULTS AND CONCLUSION: We demonstrated that exposure of the epithelium to CSE and exposure of the mice to CS can induce EMT by activating the Akt signaling pathway. Intragastric application of MK-2206 at a low dose (50 mg/kg) reversed the changes of the key indicators of EMT in the lungs of CS-exposed mice, including TGF-ß1, α-SMA, vimentin, MMP-9, MMP-2, S100A4, collagen deposition, and E-cadherin. MK-2206 at a non-cytotoxic concentration (0.5 µM) or Akt knockdown consistently reversed the changes of the key indicators of EMT in the pulmonary epithelia. Moreover, we found that the effects of Akt inhibition or knockdown on the CS/CSE-induced EMT acted via the TGF-ß1/Akt/Smad/mTOR and Akt/P38 MAPK pathways. Taken together, our data offer a novel perspective on the molecular mechanism of Akt for CS-induced EMT. This finding may enhance the understanding of the mechanism behind the synergistic use of a low dose of MK-2206 to achieve antitumor efficacy with reduced adverse reactions in patients with lung cancer and COPD.

Giant Room-Temperature Magnetodielectric Response in a MOF at 0.1 Tesla.

A giant room-temperature magnetodielectric (MD) response upon the application of a small magnetic field is of fundamental importance for the practical application of a new generation of devices. Here, the giant room-temperature magnetodielectric response is demonstrated in the metal-organic framework (MOF) of [NH2 (CH3 )2 ]n [FeIII FeII(1-x) NiIIx (HCOO)6 ]n (x ≈ 0.63-0.69) (1) with its MD coefficient remaining between -20% and -24% in the 300-410 K temperature range, even at 0.1 T. Because a room-temperature magnetodielectric response has never been observed in MOFs, the present work not only provides a new type of magnetodielectric material but also takes a solid step toward the practical application of MOFs in a new generation of devices.

Soluble epoxide hydrolase inhibitor AUDA decreases bleomycin-induced pulmonary toxicity in mice by inhibiting the p38/Smad3 pathways.

Bleomycin (BLM) has potent tumor cell-killing properties that have given it an important place in cancer chemotherapy, but pulmonary toxicity is its major adverse effect. Soluble epoxide hydrolase (sEH) inhibitors have been reported to have protective effects in fibrosis models, but the effects of AUDA, an sEH inhibitor of BLM-induced pulmonary toxicity and fibrosis, remain to be researched. In this study, we assessed the effects of AUDA on the BLM-induced pulmonary fibrosis in a mouse model, and transforming growth factor (TGF)-ß1-induced epithelial proliferation and epithelial-mesenchymal transition (EMT) in vitro by monitoring changes in pulmonary function, inflammatory response, fibrotic remodeling, and signaling pathways. AUDA was administered by intragastric administration (i.g) daily for three weeks, starting at seven days after intratracheal instillation of BLM. All examinations were performed 24h after the last i.g. In vivo, AUDA significantly improved BLM-induced decline in lung function and body weight, and inhibited inflammatory cell accumulation and the mRNA and protein expression of interleukin (IL)-1ß, TGF-ß1, and matrix metalloproteinase 9 (MMP-9) in lung tissue. Moreover, AUDA attenuated BLM-induced deposition of collagen fibers, destruction of alveolar structures, and pulmonary parenchyma. Additionally, AUDA regulated the expression of α-smooth muscle actin (α-SMA) and E-cadherin by inhibiting the Smad3/p38 signaling pathway. In vitro, AUDA significantly inhibited TGF-ß1-induced epithelial cells and fibroblast proliferation, reduced sEH expression and α-SMA expression, and increased epoxyeicosatrienoic acid (EET) levels and E-cadherin expression in epithelial cells. These effects were blocked by AUDA by downregulating the Smad3 and p38 signaling pathways. Taken together, these data indicate that treatment with sEH inhibitors may improve BLM-induced pulmonary toxicity.

Grape seed extract ameliorates bleomycin-induced mouse pulmonary fibrosis.

Pulmonary fibrosis is common in a variety of inflammatory lung diseases, such as interstitial pneumonia, chronic obstructive pulmonary disease, and silicosis. There is currently no effective clinical drug treatment. It has been reported that grape seed extracts (GSE) has extensive pharmacological effects with minimal toxicity. Although it has been found that GSE can improve the lung collagen deposition and fibrosis pathology induced by bleomycin in rat, its effects on pulmonary function, inflammation, growth factors, matrix metalloproteinases and epithelial-mesenchymal transition remain to be researched. In the present study, we studied whether GSE provided protection against bleomycin (BLM)-induced mouse pulmonary fibrosis. ICR strain mice were treated with BLM in order to establish pulmonary fibrosis models. GSE was given daily via intragastric administration for three weeks starting at one day after intratracheal instillation. GSE at 50 or 100mg/kg significantly reduced BLM-induced inflammatory cells infiltration, proinflammatory factor protein expression, and hydroxyproline in lung tissues, and improved pulmonary function in mice. Additionally, treatment with GSE also significantly impaired BLM-induced increases in lung fibrotic marker expression (collagen type I alpha 1 and fibronectin 1) and decreases in an anti-fibrotic marker (E-cadherin). Further investigation indicated that the possible molecular targets of GSE are matrix metalloproteinases-9 (MMP-9) and TGF-ß1, given that treatment with GSE significantly prevented BLM-induced increases in MMP-9 and TGF-ß1 expression in the lungs. Together, these results suggest that supplementation with GSE may improve the quality of life of lung fibrosis patients by inhibiting MMP-9 and TGF-ß1 expression in the lungs.

Inhalation of ambroxol inhibits cigarette smoke-induced acute lung injury in a mouse model by inhibiting the Erk pathway.

Oral and injection administration of ambroxol has been clinically used to treat airway disease. However, little is known about its potentials in inhalation therapy. In present studies, we tested the effects of ambroxol by inhalation with intravenous administration, and explored the underlying working mechanism. The mice received 10 cigarettes exposure every day for 4 days. Inhaled solution of ambroxol was aerosolized 20 min before the exposure of cigarette smoke (CS). The effect of ambroxol on the expression of mucoprotein 5 AC (MUC5AC) and proinflammatory cytokines in NCI-H292 cells stimulated with cigarette smoke extract (CSE). Four days of daily inhalation of ambroxol at 3.75 or 7.5mg/ml for 20 min suppressed the accumulation of neutrophils and macrophages in the bronchoalveolar lavage fluid (BALF) and lung tissues, and inhibited increases in the mRNA and protein levels of tumor necrosis factor (TNF)-α, CCL-2 and KC, but not interleukin (IL)-1ß in the CS-exposed mice. Moreover, ambroxol at 3.75 or 7.5mg/ml facilitated airway mucosa cilia clearance, reduced glycosaminoglycans level in BALF and MUC5AC mRNA levels in lung tissues. The effects of ambroxol by inhalation at 7.5mg/ml was comparable to that of ambroxol at 20mg/kg i.v. and dexamethasone at 0.5mg/kg i.p. Using cultured lung epithelial cells, we demonstrated that pretreatment with ambroxol at 2 or 20 µM inhibited the CSE-induced up-regulation of MUC5AC, TNF-α, IL-1ß mRNA levels, which was through inhibiting Erk signaling pathway. Our results demonstrate the beneficial effects of ambroxol as an inhalation replace systemic administration for COPD therapy.

Epoxyeicosatrienoic acids attenuate cigarette smoke extract-induced interleukin-8 production in bronchial epithelial cells.

In response to endothelial cell activation, arachidonic acid can be converted by cytochrome P450 (CYP) epoxygenases to epoxyeicosatrienoic acids (EETs), which have potent vasodilator and anti-inflammatory properties. In this study, we investigated the effects of exogenous EETs on cigarette smoke extract (CSE)-induced inflammation in human bronchial epithelial cells (NCI-H292). We found that CSE inhibited the expression of CYP2C8 and mildly stimulated the expression of epoxide hydrolase 2 (EPHX2) but did not change the expression of CYP2J2. Treatment with 11,12-EET or 14,15-EET attenuated the CSE-induced release of interleukin (IL)-8 by inhibiting the phosphorylation of p38 mitogen-activated protein kinases (MAPKs). Our results demonstrated that CSE may reduce the anti-inflammatory ability of epithelial cells themselves by lowering the EET level. EETs from pulmonary epithelial cells may play a critical protective role on epithelial cell injury.