Objective To extract and identify primary culture rat pulmonary arterial smooth cells ( PASMCs) , and investigate the effects of hypoxia on the proliferation of PASMCs. Methods Rat PASMCs were separated by the method of tissue block anchorage, and the cellular morphology was observed under light microscope. The cells were identified by projection electron microscopy, and α-smooth muscle actin ( α-SMactin)in the cells was identified by immunohistochemistry and immunofluorescence. The primary cultured PASMCs were exposed to normoxic and/ or hypoxia condition for 2, 6, 12, 24, 48 hours respectively, thenMTT assay and PCNA ( proliferating cell nuclear antigen) immunohistochemistry were used to detect the proliferation of PASMCs. Results The cells tended to be long spindle and grew in the “peak-valley”mode under light microscope. Immunology results showed that endochylema was stained in brownish yellow, and the positive rate was beyond 96% . There were dense patch, dense body and many filaments in endochylema under projection electron microscopy. MTT assay demonstrated that the A values of PASMCs expose to hypoxia were higher than that of nomoxia. Comparing with normoxia, the A values of PASMCs exposed to hypoxia increased after 12 hours ( P lt;0. 05) , significantly increased after 24 hours ( P lt;0. 01) . Compared with 2 hours’exposure to hypoxia, the A values increased after 12 hours( P lt; 0. 05) , markedly increased after 24 hours ( P lt; 0. 01 ) , which after 48 hours was similar with 24 hours. The result of PCNA immunohistochemistry was consistent with that of MTT. Conclusions The tissue explants adherent method is simple and convenient, and can easily obtain rat PASMCs with high purity and stability. Hypoxia canpromote the proliferation of PASMCs.
Objective To investigate the effects of dust mite allergen Derp1 on the expressions of IL-6 and IL-8 in primary rat bronchial epithelial cells. Methods The primary rat bronchial epithelial cells were divided into a control group and three experimental groups. In the experimental groups, the cells were cultured with 3 different concentrations of Derp1 ( 1, 5, 10 μg/mL) for 3 different time ( 4, 8, 24 h) .Inverted microscope was employed to observe the morphological changes of bronchial epithelial cells and intercellular space, and supernatants were assayed for IL-6 and IL-8 with ELISA. Results Complete flattening of single cells layer was observed in the control group. In the experimental groups, the cells treated with Derp1 allergen showed no obvious changes in the cell morphology and intercellular space. However,There was a significant change in the level of cytokines production compared with the control group. The levels of IL-6 and IL-8 began to rise at 4 h, and reach to high level at 8 h, especially in the 5 and 10 μg/mL groups ( P lt;0. 01) . In the 24h group, the concentrations further increased but not reach statistical difference compared with 8h group ( P gt; 0. 05) . Conclusions The Derp1 allergen can stimulate the release of inflammatory cytokines such as IL-6 and IL-8 fromthe rat trachea- bronchia epithelial cells. It is suggested that dust mite allergen -induced cytokines may play important roles in the pathogenesis of allergic asthma.
Objective To investigate the expression and localization of activating transcription factor 3 ( ATF3) and ATF4 in lung of rats with chronic obstructive pulmonary disease ( COPD) , and explore their possible roles in the pathogenesis of COPD. Methods Twenty-two SD rats were randomly divided into a COPD group and a control group. The COPD model was established by cigarette smoking and intratracheal instillation of lipopolysaccharide. The lung function was measured and the pathological changes were observed under light microscope. In situ hybridization, reverse transcription-polymerase chain reaction ( RTPCR), immunohistochemistry, and Western blot techniques were used to detect the mRNA and protein expressions of ATF3 and ATF4 in rat lung. Results The lung function of the COPD group was significantlydecreased. The rats in the COPD group shared specific pathological features of COPD. Immunohistochemical and Western blot results showed that the protein expressions of ATF3 and ATF4 were higher in the COPD group than those in the control group ( P lt;0. 05) . In situ hybridization and RT-PCR results showed that themRNA expressions of ATF3 and ATF4 in the COPD group were also significantly higher than those in the control group ( P lt;0. 05) . Conclusions The expressions of ATF3 and ATF4 are significantly up-regulated in COPD. These findings suggest that ATF3 and ATF4 may play important roles in the oxidative and antioxidative imbalance in the pathogenesis of COPD.
Objective To investigate whether cigarette smoke promote endoplasmic reticulum associated apoptosis gene Caspase-12 expression. Methods Forty adult male Wistar rats were randomly divided into four groups, ie. group A ( control group) , group B ( exposed to cigarette smoke for two months) ,group C ( exposed to cigarette smoke for four months) , and group D ( exposed to cigarette smoke for four months, then quit smoking for one month) . The COPD rat model was established with passive smoking.Percentage of forced expiratory volume in first 0. 3 second to forced vital capacity ( FEV0. 3 /FVC) and peak expiratory flow ( PEF) were measured. Reverse transcriptase-polymerase chain reaction ( RT-PCR) was used to determine the mRNA expression of Caspase-12. Immunohistochemistry and Western blot were used todetermine the protein expression of Caspase-12. Caspase-12-fluorometric-assay-kit was used to determine Caspase-12 activity. Results The pulmonary function decreased ( P lt; 0. 05) and the lung structure was damaged in the group B compared with the group A. The lung function markedly decreased( P lt; 0. 05) andthe lung structure was obviously damaged in the group C compared with the group B. The pulmonary function had minor improvement( P gt; 0. 05) , and the lung structure injury was also significant in the group D in contrast with the group C. The expression and activity of Caspase-12 were remarkably increased in the group B compared with the group A( P lt; 0. 05) , elevated significantly in the group C compared with the group B ( P lt; 0. 05) , decreased slightly in the group D compared with the group C ( P gt; 0. 05 ) . Conclusion Cigarette smoke promotes the development of COPD by inducing the endoplasmic reticulum associated apoptosis gene Caspase-12 expression.
Objective To examine the effects of hypoxia on endothelial-to-mesenchymal transition of porcine pulmonary arterial endothelial cells ( PAECs) .Methods The porcine PAECs were divided into a normoxia group and a hypoxia group. The cells in two groups were exposed to normoxic or hypoxic condition for 1,4, and 7 days respectively. The immunofluorescence,Western blot and RT-PCR were used to detect the protein and mRNA expressions of VE-cadherin and α-SMA. Results The porcine primary PAECs formed typical monolayer of cobblestone appearance on normoxia condition, and had a spindle-shaped appearance on hypoxia condition. Immunofluorescence results showed that these PAECs expressed mesenchymal cells specific marker of α-SMA. With the hypoxic time prolongation, the ratio of transdifferentiated smooth musclelike cells from PAECs was gradually increased ( P lt; 0. 01) . Western blot assay demonstrated that the expression level of VE-cadherin protein and mRNA was reduced gradually, but the expression level of α-SMA protein and mRNA was increased. Conclusion Hypoxia can induce endothelial-to-mesenchymal transition, which may be involved in the development of a variety of diseases.
Objective To explore changes of 3’-glutamylcysteine synthetase( γ-GCS)and reduced glutathione(GSH)in patients with bronchial asthma．Methods Ten patients with acute asthma were enrolled and treated for six weeks according to guideline recommendations．Levels of -GCS，GSH and malondialdehyde(MDA)in total cells in induced sputum and GSH，MDA，reactive oxygen(ROS)in selum were measured and compared before and after therapy．Ten healthy volunteers were as normal contro1．Meanwhile，the pulmonary function(FEVl％pred)was measured and asthmatic symptoms were quantified using Hogg’s way．Results A．In serum and sputum of the asthma patients，GSH were lower and MDA were higher before treatment than those of the control(Plt;0．01)．And -GCS in induced sputumwere higher before treatment than those of contro1．B．After treated for six weeks．levels of GSH in serum and sputum of the asthma patients increased copmpared to baseline(all Plt;0．01)，but were still lower than that of control(Plt;0．05)．Activities of MDA in serum and sputum and -GCS in sputum were elevated compared to baseline(Plt;0．01)，but still higher than that of control(all Plt;0．05)．C．Levels of GSH in serum of all patients were correlated negatively witll asthmatic symptom scores and levels of MDA and ROS(r=－0.701，－0.901，－0.878；Plt;0.05，lt;0.01，lt;0.01)．There was a positive relationship between levels ofGSH in serum and FEV1％pred(r=0．854，Plt;0．01)．In induced sputum，activities of 3’-GCS in all patients was correlated positively with their asthmatic symptom scores and level of MDA f r=0．804，0.926；Plt;0.05，lt;0.叭)．Conclusion γ-GCS and GSH may participate the reaction of
Objective To explore the regulation of peroxisome proliferator-activated receptor γ coactivator 1α( PGC-1α) and NF-E2-related factor 2( Nrf2) on expression of γ-glutamylcysteine synthetase ( γ-GCS) , and their roles in chronic obstructive pulmonary disease( COPD) . Methods Twenty-four SD rats were randomly divided into a COPD group and a normal control group. COPD model was established by intratracheal instillation of lipopolysaccharide ( LPS) and daily exposure to cigarette smog in the COPD group. The lung function was measured and the pathological changes were observed. The protein and mRNA expressions of PGC-1α, Nrf2, and γ-GCS in lung tissue were measured by immunohistochemistry, Western blot, in site hybridization ( ISH) , and reverse transcription-polymerase chain reaction ( RT-PCR ) ,respectively. Results In the COPD group, the pulmonary function ( FEV0. 3, FEV0. 3 /FVC, PEF) damage and lung pathological changes were conformed as morphological characteristics of COPD. The mRNA of PGC-1α and Nrf2 expressed in lung tissues of two group rats in the region consistent with γ-GCS mRNA. The protein and mRNA expressions of PGC-1αand γ-GCS were markedly increased in the COPD group( all P lt;0. 05) ,and the protein expression of Nrf2 was obviously up-regulated ( P lt; 0. 01) , while Nrf2 mRNA had no significant difference between the two groups( P gt;0. 05 ) . Linear correlation analysis showed that the level ofPGC-1αprotein was positively correlated with the levels of Nrf2 protein and mRNA ( r = 0. 775, 0. 515, all P lt; 0. 01) , and the levels of PGC-1αand Nrf2 protein were positively correlated with the levels of γ-GCS protein ( r = 0. 531, 0. 575, all P lt; 0. 01) and mRNA ( r = 0. 616, 0. 634, all P lt; 0. 01) . Conclusions PGC-1α, which may serve as a co-activator of Nrf2, can up-regulate the expression of γ-GCS gene cooperatively with Nrf2 through a common pathway, which might involve in the oxidative and antioxidative mechanism in the pathogenesis of COPD.
Objective To investigate the dynamic expression of small ubiquitin-related modifiers-1 ( SUMO-1) in lung tissue in different phases of rat model of hypoxic pulmonary hypertension( HPH) .Methods Forty Wistar rats were randomly divided into 5 groups, and exposed to normoxia or to normobaric intermittent hypoxia for 3, 7, 14 or 21 days, respectively. Mean pulmonary arterial pressure( mPAP) , right ventricle hypertrophy index ( RVHI) , and the ratio of the vessel wall area to the total area( WA% ) weremeasured. RT-PCR and in situ hybridization were used to determine the mRNA expression of SUMO-1.Immunohistochemistry and Western blot were used to determine the protein expression of SUMO-1. Results The hypoxic rats developed pulmonary vascular remodeling in pulmonary arterioles after 7 days of hypoxia,with WA% and mPAP significantly higher than those in the normal control. Pulmonary vascular remodeling aggravated with much higherWA% and mPAP afer 14 days of hypoxia, and reached the peak afer 21 days of hypoxia. SUMO-1 mRNA and protein expression markedly increased after 3 days of hypoxia, and reached peak after 14 days. After 21 days of hypoxia, SUMO-1 mRNA expression weakened but still higher than that in the normal control ( P lt; 0. 05) , and SUMO-1 protein expression remained stable. SUMO-1 mRNA and protein expression were positively correlated with mPAP, WA% and RVHI( all P lt; 0. 01) . Conclusion SUMO-1 is transcriptionally induced in lung tissue under chronic hypoxia, and thus involves in the pathogenesis of HPH.