OBJECTIVE The objective of this study was to characterize the neurotransmitter systems that cause constriction of murine airways.METHODS Murine precision cut lung slices(PCLS)and trachea were prepared,placed into perf...OBJECTIVE The objective of this study was to characterize the neurotransmitter systems that cause constriction of murine airways.METHODS Murine precision cut lung slices(PCLS)and trachea were prepared,placed into perfusion chambers equipped with platinum electrodes and stimulated transmurally(1.0 ms,50 V,0.1-30 Hz).To measure PCLS constriction,changes in airway luminal area in response to electric field stimulation(EFS)were captured as video images quantified using Image J software.For trachea,changes in isometric tension were recorded using Grass force transducers.Frequency response curves were generated in the absence and the presence of the inhibitors magnesium,atropine and capsaicin and responses analyzed and compared using a student's t-test(P<0.05).RESULTS EFS caused airway constriction in a frequency-dependent manner that was best fit by a biphasic curve.Neuron-specific stimulation was verified by Mg^(2+) blockade.Maximum airway constriction to 30 Hz EFS in PCLS was(51.8±3.0)%while tracheal constriction averaged(551±80)mg.Interestingly,in PCLS the muscarinic receptor antagonist atropine(10μmol·L^(-1))blocked(99.5±7.2)%of EFS induced constriction at 1 Hz,but only blocked(23.3±3.8)%of EFS induced constriction at 30 Hz and eliminated the first phase but not the second phase of the biphasic EFS response.Treatment with capsaicin to deplete sensory neurotransmitters significantly increased EFS constriction supporting the presence of sensory neurotransmitter systems in airways.CONCLUSION These data are consistent with parasympathetic constriction of airways by acetylcholine at lower EFS frequencies while higher frequencies release sensory dilator neurotransmitters.These data provide evidence for multiple nerve types innervating airways which may provide novel targets for treatment of lung disease.展开更多
To investigate airflow pattern and its impact on particle deposition, finite-volume based computational fluid dynamics (CFD) simulations were conducted in the diseased triple-bifitrcation airways. Computations were ...To investigate airflow pattern and its impact on particle deposition, finite-volume based computational fluid dynamics (CFD) simulations were conducted in the diseased triple-bifitrcation airways. Computations were carried out for twenty Reynolds numbers ranging from 100 to 2 000 in the step of 100. Particles in the size range of 1-10 μm were conducted. Two particle deposition mechanisms (gravitational sedimentation and inertial impaction) were considered. The results indicate that there are strong relationship between airflow structures and particle deposition patterns. Deposition efficiency is different for different particles in the whole range of the respiratory rates. Particles in different sizes can deposit at different sites. Smaller particles can be uniformly deposited at the inside wall of the considered model. Larger particles can be mainly deposited in the proximal bifurcations. Deposition fraction varies a lot for different inlet Reynolds numbers. For lower Reynolds numbers, deposition fraction is relatively small and varies a little with varying the diameters. For Reynolds number to target the aerosols at the specific site. higher Reynolds numbers, there is a most efficient diameter for each展开更多
自从美国麻醉医师协会(american society of anesthesiologists,ASA)困难气道管理实践指南在1993年首次发布并在2003年和2013年进行了两次更新以来[13],多个国家的麻醉医师协会均发布了相关的困难气道管理实践指南,包括英国困难气道...自从美国麻醉医师协会(american society of anesthesiologists,ASA)困难气道管理实践指南在1993年首次发布并在2003年和2013年进行了两次更新以来[13],多个国家的麻醉医师协会均发布了相关的困难气道管理实践指南,包括英国困难气道协会(difficult airway society,DAS)[4]、展开更多
Introduction A disintegrin and metalloproteinase 33(ADAM33)has been identified as a susceptibility gene for asthma<sup>[1]</sup>,In particular,ADAM33 mRNA is highly expressed in airway smooth muscle cell...Introduction A disintegrin and metalloproteinase 33(ADAM33)has been identified as a susceptibility gene for asthma<sup>[1]</sup>,In particular,ADAM33 mRNA is highly expressed in airway smooth muscle cells(ASMCs)and the level of soluble ADAM33(sADAM33)is known to inversely correlate with lung function such as bronchial hyperresponsiveness(BHR)<sup>[2]</sup>that is ultimately determined by the mechanical behaviors of ASMCs.However,few have studied how sADAM33would affect ASMC mechanics.Here,we manipulated the expression of SADAM33 in展开更多
Background and objective Airway stent placement is the effective regimen for central airway obstruction(CAO),while its application scenarios varied.This study aimed to make clinical comparison of airway stent placemen...Background and objective Airway stent placement is the effective regimen for central airway obstruction(CAO),while its application scenarios varied.This study aimed to make clinical comparison of airway stent placement in the intervention room and operating room.Methods Patients underwent airway stent placement between 2014 and 2018 were included in this retrospective case-control study.Clinical performance of airway stent placement in intervention room and operating room were compared.Results 82 patients were included in this study,including 39 in the intervention room and 43 in the operating room.Patients treated in the intervention room had lower Charlson comorbidity index(CCI)(P=0.018)and received less Y-shaped stents(P<0.001).Better clinical response(P=0.026),more stents placed(P<0.001)and longer length of stent(P<0.001)were observed in operating room,while there was no significantly statistical difference of stent-related complications and post-stent survival rate between the two groups.Extracorporeal membrane oxygenation(ECMO)supported airway stent placement procedures were performed in the operating room,which provided definitive safety support for high-risk intervention.Conclusion Patients with CAO could benefit from the operating room scenario,and airway stent placement in the operating room is more suitable for patients with higher CCI scores and receiving more complicated procedures.展开更多
To study the mechanism of unsteady heat-moisture transfer of wet surrounding rock in deep mining, a series of experiments with different initial and boundary conditions were carried out. Test results show that rock te...To study the mechanism of unsteady heat-moisture transfer of wet surrounding rock in deep mining, a series of experiments with different initial and boundary conditions were carried out. Test results show that rock temperature decreases quickly at the initial stage, and reduces slowly to be a constant value finally for transient heat-moisture transfer. The quasi-steady surface temperature of wet airway is lower than that of dry airway due to the moisture transfer. The diffusion radius is less than the cooling radius owing to the large diffusion resistance. The outlet airflow enthalpy of wet airway is much larger than that of dry airway. Latent heat caused by the moisture transfer plays a significant role in a deep thermal environment. For periodic heat-moisture transfer, temperature, humidity and enthalpy of outlet airflow and rock temperature also change periodically. The wave amplitude of rock temperature decreases gradually with increasing distance away from the airway surface, and the wave phase of rock temperature is also behind that of airflow. Moreover, direction of the heat-moisture transfer between airway and airflow is bidirectional, which is different from results of transient transfer.展开更多
Smooth muscle cells can work properly over a large length range,drastic reorganization of the cytoskeletal structure has to occur,but the mechanism behind the process of cytoskeleton reorganization of smooth muscle is...Smooth muscle cells can work properly over a large length range,drastic reorganization of the cytoskeletal structure has to occur,but the mechanism behind the process of cytoskeleton reorganization of smooth muscle is still poorly understood,especially with respect to unique problem of maintaining force generation and transmission within the confine of an ever-changing cytoskeleton in smooth muscle.Using a cytoskeletal preparation derived from skinned airway smooth muscle,we aimed at separating the contribution of actomyosin interaction and elucidating the cytoskeletal stiffness in smooth muscle.The results indicate that there is a Ca++de-展开更多
Targeted peptides have been identified as showing great promise for treatment of various diseases including asthma.Asthma is considered of difficuIt-to-treat due to its unclear etiology,thus usually requiring life-lon...Targeted peptides have been identified as showing great promise for treatment of various diseases including asthma.Asthma is considered of difficuIt-to-treat due to its unclear etiology,thus usually requiring life-long treatment.Current strategies for asthma therapy are hampered with undesirable side effects,poor targeting and failure in modulating airway hyperresponsiveness,leading to pressing need of developing more targeted and effective therapeutic sites for asthma.Recently,a disintegrin and metalloproteinase 8(ADAM8)have been shown to over-展开更多
An epidemiologic health survey was carried out among 314 workers in one of grain elevators in Shenyang.A medical and occupational questionnaire was administered by trained interviewers. Spirometry was performed on sit...An epidemiologic health survey was carried out among 314 workers in one of grain elevators in Shenyang.A medical and occupational questionnaire was administered by trained interviewers. Spirometry was performed on site. 61.47% of the grain workers complained of one or more respiratory symptoms during or after exposure to airborne grain dust.The prevalence of various symptoms was significantly higher among grain workers than control subjects. 15.6% of the grain workers had episodes of grain fever. The mean values of V<sub>max75</sub>, V<sub>max50</sub>, and V<sub>max25</sub> was significantly lower for grain workers than control subjects, suggesting that the group of grain workers had evidence of small airway dysfunction. Pulmonary function abnormalities were associated with increased duration of employment in the grain elevator,smoking was also associated with deterioration of respiratory function.展开更多
Introduction Excessive narrowing of airways is the most important pathological feature of asthma,but its mechanism remains puzzling.One certain thing is that the contraction of airway smooth muscle(ASM)ultimately caus...Introduction Excessive narrowing of airways is the most important pathological feature of asthma,but its mechanism remains puzzling.One certain thing is that the contraction of airway smooth muscle(ASM)ultimately causes airway narrowing,thus both structural and functional alterations of airway smooth muscle(ASM)are thought as common final pathway responsible for the bronchial hyperresponsiveness(BHR),the hall mark of asthma.Many chemical and physical factors such as air pollutants,inflammatory agents,mechanical and geometrical properties of the microenvironment could influence structure and/or function of ASM cells.In addition,some re-展开更多
OBJECTIVE To develop an in vitro airway epithelial cell model suitable for the large-scale studies of compounds that can suppress lipopolysaccharide(LPS)-and tumor necrosis factor alpha(TNFα)-induced airway inflammat...OBJECTIVE To develop an in vitro airway epithelial cell model suitable for the large-scale studies of compounds that can suppress lipopolysaccharide(LPS)-and tumor necrosis factor alpha(TNFα)-induced airway inflammation.METHODS We have optimized the protocols to culture BEAS-2B,a normal human bronchial epithelial cell line,in glass-bottom 384-well microtiter plates.The cells were stimulated with TNFαand LPS from Pseudomonas aeruginosa,a common lunginfection pathogen in cystic fibrosis and chronic obstructive pulmonary disease.We used ELISA to measure the secretion levels of two pro-inflammatory cytokines,interleukin(IL)-6and-8,after 0,4,8,16,24 hof stimulation;and immunofluorescence microscopy to measure the nuclear translocation of RelA,a subunit of the NF-κB complex,after 0,15,30,60,120 min of stimulation.To suppress the inflammatory response,we pre-treated the cells with a specific IκB kinase-2inhibitor,TPCA-1;the main bioactive component of Andrographis paniculata,andrographolide;and DMSO control for 1h.RESULTS We found that individual stimulant(either TNFα10ng·mL-1 or LPS 10μg·mL-1)increased the IL-6and IL-8 secretion levels by^12-17 foldsas compared to DMSO controls after 8h of stimulation.The combined stimulation(10ng·mL-1 TNFαand 10μg·mL-1 LPS)induced even higher IL-6 and -8 levels(~18-21 folds)at the same time points.Importantly,our imaging study shows that the NF-κB activation is early but transient under TNFαstimulation,late but sustained under LPS stimulation,and early and sustained under the combined stimulation.Finally,we also found that TPCA-1 10μmol·L-1 or andrographolide 30μmol·L-1 drastically reduced the IL-6 and -8 levels down to 4.5-9 folds as compared to the controls.CONCLUSIONThe combined TNFαand LPS stimulations induce faster and more sustained inflammatory responses,which can still be suppressed by anti-inflammatory compounds in our cell model.These more comprehensive activations of inflammatory signaling pathways will enable us to study and distinguish the mechanisms of different anti-inflammatory compounds or natural products.展开更多
OBJECTIVE Steroid-resistant airway hyper-responsiveness(AHR)has been proposed to be related to the activation of innate host defense pathways such as those induced by LPS,IFN-γ,and LPS/IFN-γ-stimulated essential med...OBJECTIVE Steroid-resistant airway hyper-responsiveness(AHR)has been proposed to be related to the activation of innate host defense pathways such as those induced by LPS,IFN-γ,and LPS/IFN-γ-stimulated essential mediator IL-27.We investigated whether andrographolide,apreviously demonstrated anti-inflammatory bioactive molecule extracted from the plant Andrographis paniculata,could restore steroid sensitivity to block LPS/IFN-γ-induced IL-27 production and AHR viaits anti-oxidative property.METHODS Mouse macrophage cell line Raw264.7,mouse primary pulmonary monocyte/macrophage,and BALB/c mouse were treated with LPS/IFN-γ,in the presence and absence of increasing doses of dexamethasone and/or andrographolide.mRNA and protein levels of IL-27 in vitro and in vivo were examined,and mouse AHR was assessed.RESULTS Dexamethasone alone failed to inhibit LPS/IFN-γ-induced IL-27 and AHR in mice.Andrographolide significantly facilitated the suppressive effect of dexamethasone on LPS/IFN-γ-induced IL-27 level in macrophage cell line and primary monocyte/macrophage,mouse bronchoalveolar lavage fluid and lung tissue,and furthermore on the incurring AHR.LPS/IFN-γdid not impede nuclear translocation of glucocorticoid receptors but diminishthe protein level of histone deacetylase-2(HDAC2),an essential epigenetic enzymeresponsible for steroid anti-inflammatory action.Andrographolide at low doses(5μmol·L-1 in vitro;1mg·kg-1,ip in vivo)restored nuclear HDAC2 protein levels both in cells and in mouse lungs,possibly via suppression of PI3K/Akt signaling pathway and up-regulation of the anti-oxidative transcription factor Nrf-2level.CONCLUSION Our data suggest that andrographolide may resensitize steroid action on blocking LPS/IFN-γ-induced IL-27 and resultant AHR by restoring HDAC2 level.展开更多
OBJECTIVE Airway wall remodeling(AWR),which refers to structural changes in the airway,is a key characteristic of asthma.Airway smooth muscle(ASM)cell hypertrophy and hyperplasia contributes to AWR.Glucocorticoids,whi...OBJECTIVE Airway wall remodeling(AWR),which refers to structural changes in the airway,is a key characteristic of asthma.Airway smooth muscle(ASM)cell hypertrophy and hyperplasia contributes to AWR.Glucocorticoids,which are used as first line therapy for the treatment of asthma,reduce ASM proliferation but the magnitude of their anti-proliferative actions is dependent on the mitogen used.Moreover,glucocorticoid therapy is accompanied by many side effects.Artesunate,a semi-synthetic artemisinin derivative,has been widely used to treat malaria with minimal toxicity.Artesunate has been shown to attenuate allergic airway inflammation in mice.However,its role in treating AWR in asthma is not known.In this study,we hypothesize that artesunate has anti-proliferative actions on ASM cells,potentially reversing AWR.METHODS and RESULTS Quiescent primary human ASM cells were pre-treated(1h)with artesunate(3,10,30μmol·L-1)before being stimulated with either FBS(10%)or thrombin(0.3U·mL-1).Following 48 h stimulation with mitogen,cells were counted using a haemocytometer.Dexamethasone(Dex,100nmol·L-1)was used as a positive control.Artesunate concentration-dependently reduced cell number and the magnitude of inhibition appeared to be non-mitogen dependent.Moreover,we examined the effect of artesunate on two important signalling proteins involved in cell proliferation,ERK1/2phosphorylation and cyclin D1 protein levels.Artesunate reduced cyclin D1 protein levels significantly following 20 h stimulation with either thrombin or FBS but had no effect on ERK1/2 phosphorylation following 6h stimulation.Importantly,artesunate(30μmol·L-1),but not Dex,inhibited the phosphorylation of Akt,which is upstream of cyclin D1.Next,we show that the inhibitory effect of artesunate,but not Dex,on ASM cell number is retained at least 24h post-treatment following stimulation with FBS.In an acute murine model of allergic asthma,artesunate treatment decreased sm-α-actin positive cells and cyclin D1 protein abundance in the ovalbumin sensitized and challenged mice.CONCLUSION We have shown that artesunate regulates the PI3K/Akt pathway to inhibit the proliferation of primary human cultured ASM cells.This is an alternative mode of action,in comparison to glucocorticoids such as Dex.The anti-proliferative effect of artesunate was further validated in vivo.Thus,our study provides a basis for the future development of artesunate as a novel anti-AWR agent that targets ASM hyperplasia via the PI3K/Akt pathway.Moreover,artesunate may be used as an add-on therapy for asthmatic patients.展开更多
文摘OBJECTIVE The objective of this study was to characterize the neurotransmitter systems that cause constriction of murine airways.METHODS Murine precision cut lung slices(PCLS)and trachea were prepared,placed into perfusion chambers equipped with platinum electrodes and stimulated transmurally(1.0 ms,50 V,0.1-30 Hz).To measure PCLS constriction,changes in airway luminal area in response to electric field stimulation(EFS)were captured as video images quantified using Image J software.For trachea,changes in isometric tension were recorded using Grass force transducers.Frequency response curves were generated in the absence and the presence of the inhibitors magnesium,atropine and capsaicin and responses analyzed and compared using a student's t-test(P<0.05).RESULTS EFS caused airway constriction in a frequency-dependent manner that was best fit by a biphasic curve.Neuron-specific stimulation was verified by Mg^(2+) blockade.Maximum airway constriction to 30 Hz EFS in PCLS was(51.8±3.0)%while tracheal constriction averaged(551±80)mg.Interestingly,in PCLS the muscarinic receptor antagonist atropine(10μmol·L^(-1))blocked(99.5±7.2)%of EFS induced constriction at 1 Hz,but only blocked(23.3±3.8)%of EFS induced constriction at 30 Hz and eliminated the first phase but not the second phase of the biphasic EFS response.Treatment with capsaicin to deplete sensory neurotransmitters significantly increased EFS constriction supporting the presence of sensory neurotransmitter systems in airways.CONCLUSION These data are consistent with parasympathetic constriction of airways by acetylcholine at lower EFS frequencies while higher frequencies release sensory dilator neurotransmitters.These data provide evidence for multiple nerve types innervating airways which may provide novel targets for treatment of lung disease.
基金Project(51178466) supported by the National Natural Science Foundation of ChinaProject(200545) supported by the Foundation for the Author of National Excellent Doctoral Dissertation of ChinaProject(2011JQ006) supported by the Fundamental Research Funds of the Central Universities of China
文摘To investigate airflow pattern and its impact on particle deposition, finite-volume based computational fluid dynamics (CFD) simulations were conducted in the diseased triple-bifitrcation airways. Computations were carried out for twenty Reynolds numbers ranging from 100 to 2 000 in the step of 100. Particles in the size range of 1-10 μm were conducted. Two particle deposition mechanisms (gravitational sedimentation and inertial impaction) were considered. The results indicate that there are strong relationship between airflow structures and particle deposition patterns. Deposition efficiency is different for different particles in the whole range of the respiratory rates. Particles in different sizes can deposit at different sites. Smaller particles can be uniformly deposited at the inside wall of the considered model. Larger particles can be mainly deposited in the proximal bifurcations. Deposition fraction varies a lot for different inlet Reynolds numbers. For lower Reynolds numbers, deposition fraction is relatively small and varies a little with varying the diameters. For Reynolds number to target the aerosols at the specific site. higher Reynolds numbers, there is a most efficient diameter for each
文摘自从美国麻醉医师协会(american society of anesthesiologists,ASA)困难气道管理实践指南在1993年首次发布并在2003年和2013年进行了两次更新以来[13],多个国家的麻醉医师协会均发布了相关的困难气道管理实践指南,包括英国困难气道协会(difficult airway society,DAS)[4]、
基金supported by National Natural Science Foundation of China(11172340)Training Program for Hundreds of Distinguished Leading Scientists of ChongqingSpecialized Research Fund for the Doctoral Program of Higher Education of China(20120191120032)
文摘Introduction A disintegrin and metalloproteinase 33(ADAM33)has been identified as a susceptibility gene for asthma<sup>[1]</sup>,In particular,ADAM33 mRNA is highly expressed in airway smooth muscle cells(ASMCs)and the level of soluble ADAM33(sADAM33)is known to inversely correlate with lung function such as bronchial hyperresponsiveness(BHR)<sup>[2]</sup>that is ultimately determined by the mechanical behaviors of ASMCs.However,few have studied how sADAM33would affect ASMC mechanics.Here,we manipulated the expression of SADAM33 in
文摘Background and objective Airway stent placement is the effective regimen for central airway obstruction(CAO),while its application scenarios varied.This study aimed to make clinical comparison of airway stent placement in the intervention room and operating room.Methods Patients underwent airway stent placement between 2014 and 2018 were included in this retrospective case-control study.Clinical performance of airway stent placement in intervention room and operating room were compared.Results 82 patients were included in this study,including 39 in the intervention room and 43 in the operating room.Patients treated in the intervention room had lower Charlson comorbidity index(CCI)(P=0.018)and received less Y-shaped stents(P<0.001).Better clinical response(P=0.026),more stents placed(P<0.001)and longer length of stent(P<0.001)were observed in operating room,while there was no significantly statistical difference of stent-related complications and post-stent survival rate between the two groups.Extracorporeal membrane oxygenation(ECMO)supported airway stent placement procedures were performed in the operating room,which provided definitive safety support for high-risk intervention.Conclusion Patients with CAO could benefit from the operating room scenario,and airway stent placement in the operating room is more suitable for patients with higher CCI scores and receiving more complicated procedures.
基金Foundation item: Project(2012CB026103) supported by the National Basic Research Program of China Project(51204170) supported by the National Natural Science Foundation of China+2 种基金 Project(2011M500974) supported by Postdoctoral Science Foundation of China Project (2011QNA16) supported by Fundamental Research Funds for the Central Universities, China Project(PDll01) supported by Postdoctoral Foundation of State Key Laboratory for Geomechanics and Deep Underground Engineering, China
文摘To study the mechanism of unsteady heat-moisture transfer of wet surrounding rock in deep mining, a series of experiments with different initial and boundary conditions were carried out. Test results show that rock temperature decreases quickly at the initial stage, and reduces slowly to be a constant value finally for transient heat-moisture transfer. The quasi-steady surface temperature of wet airway is lower than that of dry airway due to the moisture transfer. The diffusion radius is less than the cooling radius owing to the large diffusion resistance. The outlet airflow enthalpy of wet airway is much larger than that of dry airway. Latent heat caused by the moisture transfer plays a significant role in a deep thermal environment. For periodic heat-moisture transfer, temperature, humidity and enthalpy of outlet airflow and rock temperature also change periodically. The wave amplitude of rock temperature decreases gradually with increasing distance away from the airway surface, and the wave phase of rock temperature is also behind that of airflow. Moreover, direction of the heat-moisture transfer between airway and airflow is bidirectional, which is different from results of transient transfer.
基金supported by National Natural Science Foundation of China(11172340)Training Program for Hundreds of Distinguished Leading Scientists of ChongqingSpecialized Research Fund for the Doctoral Program of Higher Education of China(20120191120032)
文摘Smooth muscle cells can work properly over a large length range,drastic reorganization of the cytoskeletal structure has to occur,but the mechanism behind the process of cytoskeleton reorganization of smooth muscle is still poorly understood,especially with respect to unique problem of maintaining force generation and transmission within the confine of an ever-changing cytoskeleton in smooth muscle.Using a cytoskeletal preparation derived from skinned airway smooth muscle,we aimed at separating the contribution of actomyosin interaction and elucidating the cytoskeletal stiffness in smooth muscle.The results indicate that there is a Ca++de-
基金supported by National Natural Science Foundation of China(11172340)Training Program for Hundreds of Distinguished Leading Scientists of Chongqing,Specialized Research Fund for the Doctoral Program of Higher Education of China(20120191120032)
文摘Targeted peptides have been identified as showing great promise for treatment of various diseases including asthma.Asthma is considered of difficuIt-to-treat due to its unclear etiology,thus usually requiring life-long treatment.Current strategies for asthma therapy are hampered with undesirable side effects,poor targeting and failure in modulating airway hyperresponsiveness,leading to pressing need of developing more targeted and effective therapeutic sites for asthma.Recently,a disintegrin and metalloproteinase 8(ADAM8)have been shown to over-
文摘An epidemiologic health survey was carried out among 314 workers in one of grain elevators in Shenyang.A medical and occupational questionnaire was administered by trained interviewers. Spirometry was performed on site. 61.47% of the grain workers complained of one or more respiratory symptoms during or after exposure to airborne grain dust.The prevalence of various symptoms was significantly higher among grain workers than control subjects. 15.6% of the grain workers had episodes of grain fever. The mean values of V<sub>max75</sub>, V<sub>max50</sub>, and V<sub>max25</sub> was significantly lower for grain workers than control subjects, suggesting that the group of grain workers had evidence of small airway dysfunction. Pulmonary function abnormalities were associated with increased duration of employment in the grain elevator,smoking was also associated with deterioration of respiratory function.
基金supported by National Natural Science Foundation of China(Grant No. 11172340)Training Program for Hundreds of Distinguished Leading Scientists of Chongqing+3 种基金Chongqing Natural Science Foundation(Grant No.CSTC2010BA5001,CSTC2012jjA0588)Fundamental Research Funds for the Central Universities(Grant No.CQDXWL-2012-123)Specialized Research Fund for the Doctoral Program of Higher Education of China(Grant No.20120191120032)Sharing Fund of Chongqing University's LargeScale Equipment(Grant No.2010063057,2011063048,2011063049)
文摘Introduction Excessive narrowing of airways is the most important pathological feature of asthma,but its mechanism remains puzzling.One certain thing is that the contraction of airway smooth muscle(ASM)ultimately causes airway narrowing,thus both structural and functional alterations of airway smooth muscle(ASM)are thought as common final pathway responsible for the bronchial hyperresponsiveness(BHR),the hall mark of asthma.Many chemical and physical factors such as air pollutants,inflammatory agents,mechanical and geometrical properties of the microenvironment could influence structure and/or function of ASM cells.In addition,some re-
基金The project supported by National Medical Research Council Cooperative Basic Research Grant(CBRG11nov032)the Bioinformatics Institute,Biomedical Research Council,A*STAR,Singapore
文摘OBJECTIVE To develop an in vitro airway epithelial cell model suitable for the large-scale studies of compounds that can suppress lipopolysaccharide(LPS)-and tumor necrosis factor alpha(TNFα)-induced airway inflammation.METHODS We have optimized the protocols to culture BEAS-2B,a normal human bronchial epithelial cell line,in glass-bottom 384-well microtiter plates.The cells were stimulated with TNFαand LPS from Pseudomonas aeruginosa,a common lunginfection pathogen in cystic fibrosis and chronic obstructive pulmonary disease.We used ELISA to measure the secretion levels of two pro-inflammatory cytokines,interleukin(IL)-6and-8,after 0,4,8,16,24 hof stimulation;and immunofluorescence microscopy to measure the nuclear translocation of RelA,a subunit of the NF-κB complex,after 0,15,30,60,120 min of stimulation.To suppress the inflammatory response,we pre-treated the cells with a specific IκB kinase-2inhibitor,TPCA-1;the main bioactive component of Andrographis paniculata,andrographolide;and DMSO control for 1h.RESULTS We found that individual stimulant(either TNFα10ng·mL-1 or LPS 10μg·mL-1)increased the IL-6and IL-8 secretion levels by^12-17 foldsas compared to DMSO controls after 8h of stimulation.The combined stimulation(10ng·mL-1 TNFαand 10μg·mL-1 LPS)induced even higher IL-6 and -8 levels(~18-21 folds)at the same time points.Importantly,our imaging study shows that the NF-κB activation is early but transient under TNFαstimulation,late but sustained under LPS stimulation,and early and sustained under the combined stimulation.Finally,we also found that TPCA-1 10μmol·L-1 or andrographolide 30μmol·L-1 drastically reduced the IL-6 and -8 levels down to 4.5-9 folds as compared to the controls.CONCLUSIONThe combined TNFαand LPS stimulations induce faster and more sustained inflammatory responses,which can still be suppressed by anti-inflammatory compounds in our cell model.These more comprehensive activations of inflammatory signaling pathways will enable us to study and distinguish the mechanisms of different anti-inflammatory compounds or natural products.
基金The project supported by National Medical Research Council of Singapore(NMRC/CBRG/0027/2012)
文摘OBJECTIVE Steroid-resistant airway hyper-responsiveness(AHR)has been proposed to be related to the activation of innate host defense pathways such as those induced by LPS,IFN-γ,and LPS/IFN-γ-stimulated essential mediator IL-27.We investigated whether andrographolide,apreviously demonstrated anti-inflammatory bioactive molecule extracted from the plant Andrographis paniculata,could restore steroid sensitivity to block LPS/IFN-γ-induced IL-27 production and AHR viaits anti-oxidative property.METHODS Mouse macrophage cell line Raw264.7,mouse primary pulmonary monocyte/macrophage,and BALB/c mouse were treated with LPS/IFN-γ,in the presence and absence of increasing doses of dexamethasone and/or andrographolide.mRNA and protein levels of IL-27 in vitro and in vivo were examined,and mouse AHR was assessed.RESULTS Dexamethasone alone failed to inhibit LPS/IFN-γ-induced IL-27 and AHR in mice.Andrographolide significantly facilitated the suppressive effect of dexamethasone on LPS/IFN-γ-induced IL-27 level in macrophage cell line and primary monocyte/macrophage,mouse bronchoalveolar lavage fluid and lung tissue,and furthermore on the incurring AHR.LPS/IFN-γdid not impede nuclear translocation of glucocorticoid receptors but diminishthe protein level of histone deacetylase-2(HDAC2),an essential epigenetic enzymeresponsible for steroid anti-inflammatory action.Andrographolide at low doses(5μmol·L-1 in vitro;1mg·kg-1,ip in vivo)restored nuclear HDAC2 protein levels both in cells and in mouse lungs,possibly via suppression of PI3K/Akt signaling pathway and up-regulation of the anti-oxidative transcription factor Nrf-2level.CONCLUSION Our data suggest that andrographolide may resensitize steroid action on blocking LPS/IFN-γ-induced IL-27 and resultant AHR by restoring HDAC2 level.
文摘OBJECTIVE Airway wall remodeling(AWR),which refers to structural changes in the airway,is a key characteristic of asthma.Airway smooth muscle(ASM)cell hypertrophy and hyperplasia contributes to AWR.Glucocorticoids,which are used as first line therapy for the treatment of asthma,reduce ASM proliferation but the magnitude of their anti-proliferative actions is dependent on the mitogen used.Moreover,glucocorticoid therapy is accompanied by many side effects.Artesunate,a semi-synthetic artemisinin derivative,has been widely used to treat malaria with minimal toxicity.Artesunate has been shown to attenuate allergic airway inflammation in mice.However,its role in treating AWR in asthma is not known.In this study,we hypothesize that artesunate has anti-proliferative actions on ASM cells,potentially reversing AWR.METHODS and RESULTS Quiescent primary human ASM cells were pre-treated(1h)with artesunate(3,10,30μmol·L-1)before being stimulated with either FBS(10%)or thrombin(0.3U·mL-1).Following 48 h stimulation with mitogen,cells were counted using a haemocytometer.Dexamethasone(Dex,100nmol·L-1)was used as a positive control.Artesunate concentration-dependently reduced cell number and the magnitude of inhibition appeared to be non-mitogen dependent.Moreover,we examined the effect of artesunate on two important signalling proteins involved in cell proliferation,ERK1/2phosphorylation and cyclin D1 protein levels.Artesunate reduced cyclin D1 protein levels significantly following 20 h stimulation with either thrombin or FBS but had no effect on ERK1/2 phosphorylation following 6h stimulation.Importantly,artesunate(30μmol·L-1),but not Dex,inhibited the phosphorylation of Akt,which is upstream of cyclin D1.Next,we show that the inhibitory effect of artesunate,but not Dex,on ASM cell number is retained at least 24h post-treatment following stimulation with FBS.In an acute murine model of allergic asthma,artesunate treatment decreased sm-α-actin positive cells and cyclin D1 protein abundance in the ovalbumin sensitized and challenged mice.CONCLUSION We have shown that artesunate regulates the PI3K/Akt pathway to inhibit the proliferation of primary human cultured ASM cells.This is an alternative mode of action,in comparison to glucocorticoids such as Dex.The anti-proliferative effect of artesunate was further validated in vivo.Thus,our study provides a basis for the future development of artesunate as a novel anti-AWR agent that targets ASM hyperplasia via the PI3K/Akt pathway.Moreover,artesunate may be used as an add-on therapy for asthmatic patients.