Objective To study the intervention effect of ginkgo biloba extract（GBE） on airway and vascular remodeling in rat model of chronic obstructive pulmonary disease(COPD).Methods Forty wistar rats were randomly divided into group A，B，C and D.The rat model of COPD were established by intratracheally injection of lipopolysaccharide and exposure to cigarette smoke in groups B，C and D.Groups C and D were given intraperitoneally injection with 40 mg/kg GBE respectively from day1 to day14 and day29 to day42.Forty-three days later，the rats were sacrificed for lung pathological examination.Results Group B，C and D all showed pathological changes characteristic of COPD to different extent.The average area and standard number of alveoli showed significant difference between each groups（all Plt;0.01）.The structure of bronchiole walls in group C and D show mild changes.The ratio of bronchial smooth muscle thickness to bronchial wall thickness and bronchial wall area to bronchial area of group C and D showed significant difference when compared with group A and B（all Plt;0.01）.The vascular smooth muscle cell of group C and D had mild hyperplasia and the vascular wall had slightly thickened.The ratio of vascular smooth muscle thickness to vascular wall thickness and vascular wall area to vascular area in group C and D showed significant difference when compared with group A and B（all Plt;0.01）.Conclusion GBE has inhibitory effects on airway and vascular remodeling in rats model of COPD.
Objective To investigate the effects of smoking intensity, duration and cessation on mRNA and protein expressions of matrix metalloproteinase-9 ( MMP-9) in tracheal epitheliumof rats, and the relationship between smoking or smoking cessation and airway remodeling in chronic obstructive pulmonary disease ( COPD) . Methods Forty Wistar rats were randomly divided into 5 groups, ie. a normal control group, a long termheavy smoking group, a short termheavy smoking group, a long termlight smoking group,and a smoking cessation group which was exposed to room air for 10 weeks after long term heavy smoking.The expressions of MMP-9 mRNA and protein in tracheal epithelium of rats were detected by in situ hybridization and munohistochemistry respectively. Results ( 1) The pathological changes of emphysema were observed in the lung tissue of every smoking rat, and were most sever in the long term heavy smoking group. ( 2) Compared with the normal control group [ ( 0. 88 ±0. 88) PU, ( 2. 80 ±1. 66) PU] , the expressions of MMP-9 mRNA and proteins in tracheal epithelium were remarkable elevated in the long term heavy smoking group [ ( 22. 01 ±2. 86) PU, ( 20. 81 ±2. 46) PU] , the short term heavy smoking group [ ( 14. 94 ±3. 46) PU, ( 13. 68 ±2. 00) PU] , the long term light smoking group [ ( 6. 92 ±2. 71) PU,( 8. 84 ±1. 80) PU] and the smoking cessation group [ ( 19. 00 ±3. 36) PU, ( 14. 82 ±1. 74) PU] ( P lt;0. 01) . Compared with the long term heavy smoking group, the expressions of MMP-9 in tracheal epithelium were decreased in other three smoking groups ( P lt; 0. 05) . Conclusions Smoking could increase the expression of MMP-9 in tracheal epithelium and cause trachea damage and remodeling with intensity and duration in rats. Smoking cessation could decrease the MMP-9 expression and alleviate trachea remodeling,suggesting its role in the prevention of COPD.
【Abstract】 Objective To investigate the effect of allogeneic bone marrow-derived mesenchymal stem cells ( BMSCs) transplantation on the airway inflammation and airway remodeling in chronic asthmatic mice. Methods Forty female BALB/c mice were equally randomized into four groups, ie. a normal control group, a BMSCs control group, an asthma model group, and a BMSCs transplantation group. BMSCs were generated from male donor mice, then the mice in the asthma model group and the BMSCs transplantation group were sensitized and challenged with OVA to establish chronic asthmatic mice model. Hematoxylin and eosin staining and Alcian blue-periodic acid-Schiff staining were used to analyze the effects on airway inflammation and airway remodeling after BMSC engraftment. The number of CD4 + CD25 + regulatory T cells in spleen was detected by flow cytometry. Results In lungs of the asthmamodel group, there were intensive inflammatory cells infiltration around airway and blood vessels, goblet cell proliferation, epithelial desquamation, patchy airway occlusion by hyperviscous mucus, and hypertrophy of airway smooth muscle.Airway inflammation and airway remodeling were significantly relieved in the BMSCs transplantation group.There was no obvious inflammatory cells infiltration in the airway and airway remodeling both in the normal control group and the BMSCs control group. The number of CD4 + CD25 + regulatory T cells in spleensignificantly decreased in the asthma model group compared with the two control groups ( P lt; 0. 05) , and significantly increased in the BMSCs transplantation group compared with the asthma model group ( P lt;0. 05) . There was no significant difference in the number of CD4 + CD25 + regulatory T cells in spleen betweenthe control groups and the BMSCs transplantation group. Conclusion BMSCs engraftment can up-regulate CD4 + CD25 + regulatory T cells and relieve airway inflammation and airway remodeling in asthmatic mice.
Objective To investigate the effects of 1, 25-( OH) 2D3 on the expression of matrix metalloprotease-9 ( MMP-9) and nuclear factor κB ( NF-κB) activity in a murine model of chronic asthma. Methods BALB/ c mice were sensitized and challenged with ovalbumin to establish chronic asthmatic model. The animals were randomly divided into a control group, an asthma group and a VD group. Lung sections from the mice were stained by HE and Masson’s trichrome, respectively. Morphometric analysis of the stained sections was performed using computerized image analysis system. Nuclear translocation of NF-κB p65 was examined using Western blot. The level of IκBαwas detected with real-time quantitative PCR ( RTPCR) and Western blot. In addition, the expression of MMP-9 in both activity and mRNA level was detected by gelatin zymograph and RT-PCR, respectively. Results Prominent airway remodeling developed in the asthma group, including the inflammatory cell infiltration, subepithelial collagen deposition and increased airway smooth muscle mass. In contrast, 1, 25-( OH) 2D3 attenuated these established structural changes of the airways. Stimulation with OVA induced a 7. 87-fold increase in the MMP-9 activity compared with that in the control group, and 1, 25-( OH) 2D3 treatment only induced a 3. 46-fold increase in the MMP-9 activity compared with that in the control group ( P lt;0. 05) . The mRNA level of MMP-9 in the VD group ( 3.16 ± 0.09) was decreased compared with the asthma group ( 5.74 ±0.13) ( P lt;0.05) , but itwas still higher than that in the control group ( 0.57 ±0.08) ( P lt;0.05) . 1, 25-( OH) 2D3 reduced the nuclear translocation of NF-κB p65 while up-regulated the IκBα level in lung tissue of chronic asthma. Conclusions 1, 25- ( OH) 2D3 can inhibit the NF-κB activity and down-regulate the expression of MMP-9 in lung tissue of chronic asthma, thus alleviating the established chronic asthma-induced airway remodeling.
ObjectiveTo observe the effect of metformin on airway remodeling in asthma and its possible mechanism.MethodsTwenty-eight B/N rats were randomly divided into control group, asthma group, metformin intervention group and rapamycin intervention group. After that, the asthma model was established and intervened with metformin and rapamycin. The airway resistance and airway reactivity were measured 48 hours after the last challenge, and then the lung tissue samples were collected. Histopathological examination was used to observe airway inflammatory cell infiltration, goblet cell proliferation, airway wall fibrosis and remodeling, as well as airway smooth muscle proliferation. The expression of AMPK/mTOR pathway related proteins was detected by Western blot.ResultsCompared with the asthma group, metformin and rapamycin significantly reduced the airway responsiveness induced by high concentration of acetylcholine (P<0.05), reduced the infiltration of inflammatory cells in lung tissue and the changes of airway wall structure (P<0.05), reduced goblet cell proliferation in airway epithelium, collagen fiber deposition in lung tissue and bronchial smooth muscle hyperplasia (P<0.05). Further studies showed that the effects of metformin and rapamycin were related to AMPK/mTOR pathway. Compared with the asthma group, metformin and rapamycin could significantly reduce the expression of p-mTOR, p-p70s6k1 and SKP2, while p21 protein expression was significantly increased (P<0.05). In addition, metformin and rapamycin had similar effects (P>0.05).ConclusionMetformin can alleviate airway hyperresponsiveness and airway remodeling by activating AMPK and then inhibiting mTOR pathway, which may be a potential drug for treating asthma and preventing airway remodeling.
Objective To observe the effects of fine particulate matter (PM2.5) on airway remodeling and Notch signaling pathway in mice with bronchial asthma, and explore the possible mechanism of its influence on airway remodeling in asthmatic mice. Methods Forty eight-week-old SPF female BALB/c mice were divided into a healthy control group, a healthy PM2.5 group, an asthma group and an asthma PM2.5 group by random number table, with 10 mice in each group. The asthma group and the asthma PM2.5 group were sensitized with ovalbumin to establish asthma mouse model, and the healthy PM2.5 group and the asthma PM2.5 group received aerosol inhalation of PM2.5 (510 μg/m3) after each provocation. After modeling, lung function was measured in each group. Hematoxylin and eosin staining and Masson staining were performed on the lung tissue sections of mice. Image analysis software was used to determine the circumference of the bronchial basement membrane, the total area of the bronchial wall, the area of bronchial smooth muscle and the area of collagen deposition. The expressions of Notch1, Hes1, α-smooth muscle actin (α-SMA), transforming growth factor-β1 (TGF-β1) and type Ⅰ collagen (Col-Ⅰ) were detected by immunohistochemistry and western blotting. The content of hydroxyproline (HYP) in lung tissue was determined by alkaline water method. Results The total airway wall area, airway smooth muscle area and collagen deposition area in the asthma group [(365.81±46.10), (132.80±20.14), (221.82±25.20) μm2/μm] were significantly higher than those in the healthy control group [(187.70±14.80), (89.73±8.49), (123.91±16.88) μm2/μm] (P<0.01). The healthy PM2.5 group [(244.62±42.86), (116.40±20.40), (174.91±57.41) μm2/μm] and the asthma PM2.5 group [(447.70±76.14), (236.14±36.35), (294.89±75.96) μm2/μm] were higher than those in the control group (all P<0.01). The expressions of Notch1, Hes1, α-SMA, TGF-β1 and Col-Ⅰ were strongly positive in the lung tissues of the asthmatic mice, but weak in the healthy control group. After PM2.5 intervention, compared with the control group, the expression intensity of the above molecules increased. Notch1 receptor and downstream Hes1 protein in the asthma group (0.86±0.10, 1.02±0.06) were significantly higher than those in the healthy control group (0.26±0.07, 0.56±0.09) (all P<0.01). The healthy PM2.5 group (0.44±0.06, 0.77±0.07) and asthma PM2.5 group (1.33±0.23, 1.25±0.18) were higher than the control group (all P<0.01). Airway remodeling related molecules α-SMA, TGF-β1 and Col-Ⅰ protein in the asthma group (0.60±0.04, 0.52±0.09, 0.36±0.04) were significantly higher than those in the healthy control group (0.31±0.03, 0.22±0.04, 0.23±0.04) (all P<0.01). The health PM2.5 group (0.49±0.02, 0.30±0.03, 0.28±0.03) and the asthma PM2.5 group (0.88±0.09, 0.62±0.03, 0.49±0.07) were higher than the control group (P<0.05 or P<0.01), respectively. The content of HYP in lung tissue of the asthma group (57.71±7.60) μg/100mg was significantly higher than that of healthy control group (40.53±5.73) μg/100mg. The healthy PM2.5 group (53.92±6.82) μg/100mg and asthma PM2.5 group (70.96±4.44) μg/100mg were higher than the control group (P<0.01), respectively. In asthma group and asthma PM2.5 group, the expression of Notch1 and Hes1 protein was positively correlated with the total airway wall area, airway smooth muscle area, collagen deposition area, α-SMA, TGF-β1, Col-Ⅰ and HYP (all P<0.01). Conclusion PM2.5 can promote early airway remodeling in asthma, and the activation of Notch signaling pathway may be involved in the promoting effect of PM2.5 on early airway remodeling.