Inhibitory Effect of S100A11 on Airway Smooth Muscle Contraction and Airway Hyperresponsiveness

Objective S100A11 is a member of the S100 calcium-binding protein family and has intracellular and extracellular regulatory activities.We previously reported that S100A11 was differentially expressed in the respiratory tracts of asthmatic rats as compared with normal controls.Here,we aimed to analyze the potential of S100A11 to regulate both allergen-induced airway hyperresponsiveness(AHR)as well as acetylcholine(ACh)-induced hypercontractility of airway smooth muscle(ASM)and contraction of ASM cells(ASMCs).Methods Purified recombinant rat S100A11 protein(rS100A11)was administered to OVA-sensitized and challenged rats and then the AHR of animals was measured.The relaxation effects of rS100A11 on ASM were detected using isolated tracheal rings and primary ASMCs.The expression levels of un-phosphorylated myosin light chain(MLC)and phosphorylated MLC in ASMCs were analyzed using Western blotting.Results Treatment with rS100A11 attenuated AHR in the rats.ASM contraction assays showed that rS100A11 reduced the contractile responses of isolated tracheal rings and primary ASMCs treated with ACh.In addition,rS100A11 markedly decreased the ACh-induced phosphorylation of the myosin light chain in ASMCs.Moreover,rS100A11 also suppressed the contractile response of tracheal rings in calcium-free buffer medium.Conclusion These results indicate that S100A11 protein can relieve AHR by relaxing ASM independently of extracellular calcium.Our data support the idea that S100A11 is a potential therapeutic target for reducing airway resistance in asthma patients.

REFLUX ESOPHAGITIS AND AIRWAY HYPERRESPONSIVENESS

Objectives’ To observe the effects of reflux esophagitis(RE) on the lung function and alrway reactivity,and study the mechanism of airway hyperresponsiveness(AHR) in patients with RE.Methods. Lung function measurements and airway provocation tests were performed in 31 RE patientsand 35 control subjects’ TXB, and PGF,. were determined in 20 cases of each group.Results. In RE patients the lung function was lower and the rate of AHR was higher than control sub-jects (P<0. 05). Among RE patients 25 % had higher airway sensitivity (Dminr 3u ). The TXB2 of REpatients with AHR was higher than those without AHR’ Dmin correlated significantly with TXB2 (r=0. 653, P<0. 05).Concluswhs’ RE could damage the lung function. The rate of AHR was 61 %, the high airway sensltivity was probably potential asthma, and TXB2 may play a role in the pathogenesis of AHR.

Effects of Nω-nitro-L-arginine methyl ester and aminoguanidine on lipopolysaccharide-induced airway hyperresponsiveness in guinea pigs

Background The down-regulation of constitutive nitric oxide synthase （cNOS） and up-regulation of inducible nitric oxide synthase （iNOS） are associated with the allergen-provocated airway hyperresponsiveness （AHR）. This study aimed to determine whether their alteration also plays an important role in the AHR induced by lipopolysaccharide （LPS）. Methods Hartley male guinea pigs, weighing between 250 g and 350 g, were injected with LPS at a dose of 1 mg/kg every 24 hours for three days. A non-selective NOS inhibitor, N^-nitro-L-arginine methyl ester （L-NAME）, or a selective inducible NOS inhibitor, aminoguanidine （AG）, were used thirty minutes before each injection of LPS. Airway reactions, nitric oxide （NO） production and inflammatory changes were detected 24 hours after the last dose of LPS. Results AG significantly decreased the NO production in the bronchoalveolar lavage fluid （BALF） and sharply reduced the intensity of bronchoconstdction to histamine challenge. L-NAME also significantly decreased the NO production in the BALF, but had no effect on airway reactions or, perhaps, a tendency to enhance the intensity of AHR. Conclusions The data suggest that inducible NOS contributes to the AHR induced by repetitive intraperitoneal LPS, and constitutive NOS was also involved.

Bronchial inflammatory profile in interferon-gamma-mediated immune response in asthma patients during airway response to cold stimulus

Objective:To evaluate the inflammatory pattern and the interferon(IFN)-γin the bronchial secretion of asthma patients in response to acute cold bronchoprovocation.Material and methods:We enrolled 42 patients with asthma.We assessed asthma by Asthma Control Test,the lung function by spirometry before and after the bronchodilator test,followed by collecting induced sputum.The next day,we collected exhaled breath condensate(EBC)and conducted a 3-minute isocapnic hyperventilation with cold air(IHCA),followed by collecting spontaneously produced sputum.Results:Group 1 included 20 patients with cold airway hyperresponsiveness(CAHR),and group 2 included 22 patients without CAHR.In both groups,a high level of neutrophils in bronchial secretion was observed before and after IHCA.In response to IHCA,the number of epitheliocytes in the sputum decreased to a greater extent in patients of group 1.The baseline epitheliocytes and the concentration of IFN-γafter IHCA had an inverse relationship(r=-0.60;P=0.017).The baseline IFN-γin EBC before and after IHCA was lower in group 1.Airway response to cold exposure directly correlated with IFN-γlevels after IHCA(Rs=0.42;P=0.014).Conclusion:In asthma patients with CAHR,there is a relationship between the persistence of mixed inflammation and the level of IFN-γin the bronchi.IFN-γin response to IHCA is decreased with increased cytokine utilization during cold bronchospasm,which is accompanied by the mobilization of neutrophils and the shift in the cytokine spectrum of the respiratory tract towards the T helper cells(Th)1 immune response.

RNA interference against interleukin-5 attenuates airway inflammation and hyperresponsiveness in an asthma model

Interleukin-5 (IL-5) accompanies the development of airway inflammation and hyperresponsiveness through the activation of eosinophils. Therefore, interference of IL-5 expression in lung tissue seems to be an accepted approach in asthma therapy. In this study, we designed a small interfering RNA (siRNA) to inhibit the expression of IL-5. The siRNAs against IL-5 were constructed in a lentivirus expressing system, and 1.5×106 IFU (inclusion-forming unit) lentiviruses were administered intratracheally to ovalbumin (OVA)-sensitized murine asthmatic models. Our results show that lentivirus-delivered siRNA against IL-5 efficiently inhibited the IL-5 messenger ribonucleic acid (mRNA) expression and significantly attenuated the inflammation in lung tissue. Significant decrease of eosinophils and inflammatory cells were found in peripheral blood, bronchoalveolar lavage fluid (BALF), and lung tissue. In addition, significant inhibition of airway hyperresponsiveness (AHR) was found in the mice treated with siRNA against IL-5. These observations demonstrate that siRNA delivered by means of the lentivirus system is possibly an efficacious therapeutic approach for asthma.

Exercise Training Attenuated Chronic Cigarette Smoking-induced Up-regulation of FIZZ1/RELMα in Lung of Rats

FIZZ/RELM is a new gene family named ＂found in inflammatory zone＂ （FIZZ） or ＂re- sistin-like molecule＂ （RELM）. FIZZ1/RELMct is specifically expressed in lung tissue and associated with pulmonary inflammation. Chronic cigarette smoking up-regulates FIZZ 1/RELMct expression in rat lung tissues, the mechanism of which is related to cigarette smoking-induced airway hyperresponsive- ness. To investigate the effect of exercise training on chronic cigarette smoking-induced airway hyper- responsiveness and up-regulation of FIZZ1/RELMct, rat chronic cigarette smoking model was estab- lished. The rats were treated with regular exercise training and their airway responsiveness was meas- ured. Hematoxylin and eosin （HE） staining, immunohistochemistry and in situ hybridization of lung tissues were performed to detect the expression of FIZZ1/RELMct. Results revealed that proper exercise training decreased airway hyperresponsiveness and pulmonary inflammation in rat chronic cigarette smoking model. Cigarette smoking increased the mRNA and protein levels of FIZZ1/RELMct, which were reversed by the proper exercise. It is concluded that proper exercise training prevents up-regulation of FIZZ1/RELMct induced by cigarette smoking, which may be involved in the mechanism of proper exercise training modulating airway hyperresponsiveness.

Spontaneous resolution of idiopathic intestinal obstruction after pneumonia: A case report

BACKGROUND Duodenal obstruction is a common clinical scenario that can either be mechanical or a pseudo-obstruction.Clinical management of intestinal obstruction starts from localization and proceeds to histological examination of the stenotic intestine.Systemic factors and dysfunction of distant organs might contribute to the development of intestinal obstruction.Here,we report a unique case of idiopathic mechanical duodenal obstruction,which resolved spontaneously after 3 mo of conservative treatment,but was followed by intestinal pseudo-obstruction.CASE SUMMARY An 84-year-old woman presented with worsened postprandial vomiting accompanied by prolonged pneumonia.Thorough noninvasive investigations revealed complete circumferential stenosis in the descending duodenum without known cause.Exploratory surgery was postponed due to septic shock and possible pulmonary fungal infection.Conservative treatment for 3 mo for ileus and control of pulmonary infection resolved the intestinal obstruction completely.Unfortunately,2 wk later,she had regurgitation and postprandial vomiting again,complicated by deteriorating wheezing and dyspnea.Computed tomography revealed a dilated stomach and proximal duodenum without new intestinal stricture or pulmonary infiltration.The patient fully recovered after combined treatment with antireflux agents,enema,prokinetics,and bronchodilators.CONCLUSION This complicated case highlights the inter-relationship of local and systemic contributions to ileus and gut dysfunction,which requires multidisciplinary treatment.

Investigation of the measurement of murine airway hyperres-ponsiveness and the therapeutic effects of budesonide on ovalbumin sensitized and challenged mice

Background Airway hyperresponsiveness （AHR） is one of the most important characteristics of asthma. This study investigated the parameters, by which assess the airway responsiveness under tidal ventilation.Methods Female BALB/c mice were sensitized and challenged with ovalbumin （OVA） （group A）, and part of them were treated with budesonide aerosol （group B ）. All the mice were anaesthetized and mechanically ventilated, The values of tidal volume （Vt）, airway pressure （PA）, airway flow （F）, expiratory lung resistance （RL） and dynamic compliance of the thorax and lung （CT-L ） were recorded by the AniRes2003 animal lung function system. In addition, the expiratory volume in the first O. 1 second after the start of expiration （ EV0.1 ） was obtained according to the flow-volume （F-V） curve. The maximal or minimal values of EV0.1, RL and CT-L were documented after each dose of methacholine （MCH） and compared with values from negative control group （group C）.Results （1） When the dose of MCH reached 100 ng/g or 200 ng/g, the decrease of V, in group A was much more significant than group C （P =0. 001, 〈0. 001 respectively）, but not so between groups B and group C （P =0. 974, 0. 362 respectively）. （2） With the dose of 25, 50, 100 or 200 ng/g MCH, the decrease in percentage of EV0.1 in group A was much higher than group C （P = 0.012, 0.025, 0.001, 0.003 respectively）, while that in group B showed no significant difference as compared with group C （P = 0. 507, 0. 896,0. 972,0. 785）. （3） RE and CT-L： with the dose of 200 ng/g MCH, there was a statistically significant increase of RE in group A compared to group B or group C （ P 〈 0. 001, 〈 0. 001 respectively ）, but no significant difference between groups B and C （P =0. 266）. With doses of 100 ng/g and 200 ng/g MCH, there was a statistically significant decrease of CT.L in group A compared to group B （P =0. 001,=0. 001 ） and group C （P 〈 0. 001, 〈 0. 001 respectively）, but no significant difference between groups B and C （P = 0. 775, 0. 310）. （4） Histopathology： there were eosinophilic predominant peribronchial and perivascular inflammatory influx in murine lungs after OVA sensitizing and challenging, which could be counteracted by inhalation of budesonide in group B.Conclusions The decline in EVo., in response to MCH challenge correlated with simultaneous changes in V,, RE and CT.L, but more sensitively than all the other parameters. The decline in EVo. ~ and inflammation in murine lung could be significantly alleviated by inhalation of nebulized budesonide solution, which indicated that EVo., to MCH is a valid measure of AHR in mice.

Tripterygium Polyglycosid Attenuates the Established Airway Inflammation in Asthmatic Mice

Objective： To investigate the effect of Tripterygium polyglycosid on establishing airway eosinophil infiltration and related airway hyperresponsiveness of asthmatic mice. Methods： A mature murine asthmatic model was made with ovabulmin sensitized and challenged C57BL/6 mice. Forty mice were divided into four groups with 10 mice in each group： mice sensitized and challenged with saline （WS group）, mice sensitized and challenged with ovalbumin （WO group）, mice sensitized and challenged with ovalbumin and treated with Tripterygium polyglycosid （TP group） and Dexamethasone （DXM group）. The mice were intraperitoneally injected with 20 I^g chicken ovabulmin emulsified in injected alum on days 0 and 14, then were challenged with an aerosol generated from 1% ovabulmin on days 24, 25 and 26. Tripterygium poiyglycosid was injected intraperitoneally at 50 mg/kg on days 25, 26 and 27 after ovabulmin challenge. Dexamethasone was administrated to mice at 2 mg/kg on day 21, 23 before ovabulmin challenge. The airway hyperresponsiveness, mucus production, eosinophils in parabronchial area and bronchoalveolar lavage fluid and the level of interleukin-5, granulo-macrophage clone stimulating factor in bronchoalveolar lavage fluid were measured as indexes of inflammation. Results： Tripterygium polyglycosid treatment after ovabulmin challenge completely inhibited eosinophil infiltration in bronchoalveolar lavage fluid [（0.63 ± 0.34） × 10^4 vs. （75.0± 14.8） × 10^4, P〈0.05] and the peribrochial area （12.60 ± 3.48 mm^2 vs. 379.0 ± 119.3 mm^2, P〈0.05）, mucus overproduction in airway （2.8± 1.7 vs. 7.1± 5.6, P〈0.05）, and increased interleukin-5 levels in bronchoalveolar lavage fluid （28.8±2.8 pg/mL vs. 7.5± 3.5 pg/mL, P〈0.05）. Meanwhile, Tripterygium polyglycosid treatment after ovabulmin challenge also partially inhibited airway hyperresponsiveness. The level of granulo-macrophage clone stimulating factor in bronchoalveolar lavage fluid didn＇t change with drugs intervention. Conclusions： The administration of Tripterygium polyglycosid could inhibit the established airway inflammation and reduce the airway hyperresponsiveness of allergic asthmatic mice. It provides a possible altemative therapeutic for asthma.

Active immunotherapy of allergic asthma with a recombinant human interleukin-5 protein as vaccine in a murine model

Background Eosinophils are highly related to allergic asthma inflammation. Interleukin （IL）-5 is the major chemokine of eosinophils, inhibition of the activity of IL-5 thus seems to be a potential approach to asthma therapy. The current study was performed to determine whether a recombinant human IL-5 protein as a xenogeneic vaccine has the capability of inducing anti-asthma activities. Methods Recombinant human IL-5 was used as a protein vaccine. Mouse asthma model was established to observe the anti-asthma activities. Lung histology was observed; eosinophils in blood and bronchoalveolar lavage were stained and counted, Airway hyperresponsiveness was determined by whole body plethysmograph. Antibody characters and cytokines were detected with enzyme linked immunosorbent assay （ELISA） and Western blot assay. Results Vaccination with recombinant human IL-5 protein as vaccine significantly reduced airway inflammation and airway hyperresponsiveness, and shifted the cytokine production from Th2 （IL-4） to Thl （INF-γ） in mice allergic-asthma model. Immunization with recombinant human IL-5 protein vaccine bypassed the immunological tolerance and induced production of polyclonal antibodies that were cross-reactive with murine IL-5. Conclusions Active immunization with xenogeneic homologous IL-5 may be a possible therapeutic approach to the treatment of asthma and potentially of other eosinophilic disorders.