Background： Excess mucus production is an important pathophysiological feature of chronic inflammatory airway diseases. Effective therapies are currently lacking. The aim of the study was to evaluate the effects ofcu...Background： Excess mucus production is an important pathophysiological feature of chronic inflammatory airway diseases. Effective therapies are currently lacking. The aim of the study was to evaluate the effects ofcurcumin （CUR） on lipopolysaccharide （LPS）-induced mucus secretion and inflammation, and explored the underlying mechanism in vivo and in vitro. Methods： For the in vitro study, human bronchial epithelial （NCI-H292） cells were pretreated with CUR or vehicle for 30 min, and then exposed to LPS for 24 h. Next, nuclear factor erythroid 2-related factor 2 （Nrf2） was knocked down with Nrf2 small interfering RNA （siRNA） to confirm the specific role of Nrf2 in mucin regulation of CUR in NCI-H292 cells. In vivo, C57BL/6 mice were randomly assigned to three groups （n = 7 for each group）： control group, LPS group, and LPS ＋ CUR group. Mice in LPS and LPS ＋ CUR group were injected with saline or CUR （50 mg/kg） intraperitoneally 2 h before intratracheal instillation with LPS （ 100 μg/ml） for 7 days. Cell lysate and lung tissue were obtained to measured Mucin 5AC （MUC5AC） and Nrf2 mRNA and protein expression by a real-time polymerase chain reaction and Western blotting. Bronchoalveolar lavage fluid （BALF） was collected to enumerate total cells and neutrophils. HistopathologicaI changes of the lung were observed. Data were analyzed by one-way analysis of variance. Student＇s t-test was used when two groups were compared. Results： CUR significantly decreased the expression ofMUC5AC mRNA and protein in NCI-H292 cells exposed to LPS. This effect was dose dependent （2.424 ± 0.318 vs. 7.169 ± 1.785, t = 4.534, and 1.060 ± 0.197 vs. 2.340 ± 0.209, t = 7.716; both P 〈 0.05, respectively） and accompanied by increased mRNA and protein expression of Nrf2 （1.952 ± 0.340 vs. 1.142 ± 0.176, t = -3.661, and 2.010 ± 0.209 vs. 1.089 ±0. 132, t = -6.453; both P 〈 0.05, respectively）. Furthermore, knockdown of Nrf2 with siRNA increased MUC5A C mRN A expression by 47.7%, compared with levels observed in the siRNA-negative group （6.845 ± 1.478 vs. 3.391 ± 0.517, t = -3.821, P 〈 0.05）. Knockdown of Nrf2 with siRNA also markedly increased MUC5A C protein expression in NCI-H292 cells. CUR also significantly decreased LPS-induced mRNA and protein expression of MUC5A C in mouse lung （ 1.672 ± 0.721 vs. 5.961 ± 2.452, t = 2.906, and 0.480 ± 0.191 vs. 2.290 ± 0.834, t = 3.665, respectively; both P 〈 0.05）. Alcian blue/periodic acid-Schiff staining also showed that CUR suppressed mucin production. Compared with the LPS group, the numbers of inflammatory cells （247 ± 30 vs. 334 ± 24, t = 3.901, P 〈 0.05） and neutrophils （185 ± 22 vs. 246 ± 20, t = 3.566, P 〈 0.05） in BALF decreased in the LPS ＋ CUR group, as well as reduced inflammatory cell infiltration in lung tissue. Conclusion： CUR inhibits LPS-induced airway mucus hypersecretion and inflammation through activation of Nrf2 possibly.展开更多
Objective： To observe the effect of electroacupuncture （EA） on the expressions of acetylcholine （ACh） and mucin 5AC （MUC5AC） in the lungs of rats with chronic obstructive pulmonary disease （COPD）, and explore...Objective： To observe the effect of electroacupuncture （EA） on the expressions of acetylcholine （ACh） and mucin 5AC （MUC5AC） in the lungs of rats with chronic obstructive pulmonary disease （COPD）, and explore the mechanism of EA in treating COPD. Methods： Thirty Sprague-Dawley （SD） rats were randomly divided into a control group, a COPD group, and an EA group, with 10 rats in each group. The control group was a group of normal rats. The COPD rat model was induced by cigarette smoke combined with lipopolysaccharide （LPS）. The COPD rats were treated with EA at bilateral Feishu （BL 13） and Zusanli （ST 36） in the EA group, 30 rain each time, once a day, successively for 14 d. The lung function was tested. The contents of ACh and MUC5AC in lungs and bronchoalveolar lavage fluid （BALF） were detected by enzyme-linked immunosorbent assay （ELISA）. Pearson method was used to analyze the correlation between pulmonary function and the content of MUC5AC in lungs. The mRNA and protein expressions of MUC5AC in lung tissues were detected by real-time polymerase chain reaction （RT-PCR） and Western blot （WB）, respectively. The immune response of MUC5AC was observed by immunohistochemistry. Results： Eight rats were left in each group, and the other two died. Compared with the control group, the total airway resistance （Raw） increased significantly and dynamic compliance （Cdyn） decreased significantly in the COPD group （P〈0.01）; compared with the COPD group, the Raw level declined significantly and Cdyn increased significantly in the EA group （P〈0.01）. The contents of ACh and MUC5AC in the lungs and BALF were remarkably higher in the COPD group compared with those in the control group （P〈0.01, P〈0.001）; compared with the COPD group, the contents of ACh and MUC5AC were significantly lower in the EA group （P〈0.05, P〈0.001）. There was a negative correlation between MUC5AC content and lung function （P〈0.001）. The mRNA and protein expressions of MUC5AC in the lungs were significantly higher in the COPD group than in the control group （P〈0.001）; compared with the COPD group, the expressions were significantly lower in the EA group （P〈0.01）. Compared with the control group, the immune response of MUC5AC in the airway epithelium significantly increased in the COPD group （P〈0.001）; the immune response of MUC5AC was significantly lower in the EA group compared with that in the COPD group （P〈0.001）. Conclusion： EA treatment can improve the lung function of COPD rats, which may be related to its effect in the down-regulation of ACh and MUC5AC contents in the lungs as well as the inhibition of mucus hypersecretion.展开更多
文摘Background： Excess mucus production is an important pathophysiological feature of chronic inflammatory airway diseases. Effective therapies are currently lacking. The aim of the study was to evaluate the effects ofcurcumin （CUR） on lipopolysaccharide （LPS）-induced mucus secretion and inflammation, and explored the underlying mechanism in vivo and in vitro. Methods： For the in vitro study, human bronchial epithelial （NCI-H292） cells were pretreated with CUR or vehicle for 30 min, and then exposed to LPS for 24 h. Next, nuclear factor erythroid 2-related factor 2 （Nrf2） was knocked down with Nrf2 small interfering RNA （siRNA） to confirm the specific role of Nrf2 in mucin regulation of CUR in NCI-H292 cells. In vivo, C57BL/6 mice were randomly assigned to three groups （n = 7 for each group）： control group, LPS group, and LPS ＋ CUR group. Mice in LPS and LPS ＋ CUR group were injected with saline or CUR （50 mg/kg） intraperitoneally 2 h before intratracheal instillation with LPS （ 100 μg/ml） for 7 days. Cell lysate and lung tissue were obtained to measured Mucin 5AC （MUC5AC） and Nrf2 mRNA and protein expression by a real-time polymerase chain reaction and Western blotting. Bronchoalveolar lavage fluid （BALF） was collected to enumerate total cells and neutrophils. HistopathologicaI changes of the lung were observed. Data were analyzed by one-way analysis of variance. Student＇s t-test was used when two groups were compared. Results： CUR significantly decreased the expression ofMUC5AC mRNA and protein in NCI-H292 cells exposed to LPS. This effect was dose dependent （2.424 ± 0.318 vs. 7.169 ± 1.785, t = 4.534, and 1.060 ± 0.197 vs. 2.340 ± 0.209, t = 7.716; both P 〈 0.05, respectively） and accompanied by increased mRNA and protein expression of Nrf2 （1.952 ± 0.340 vs. 1.142 ± 0.176, t = -3.661, and 2.010 ± 0.209 vs. 1.089 ±0. 132, t = -6.453; both P 〈 0.05, respectively）. Furthermore, knockdown of Nrf2 with siRNA increased MUC5A C mRN A expression by 47.7%, compared with levels observed in the siRNA-negative group （6.845 ± 1.478 vs. 3.391 ± 0.517, t = -3.821, P 〈 0.05）. Knockdown of Nrf2 with siRNA also markedly increased MUC5A C protein expression in NCI-H292 cells. CUR also significantly decreased LPS-induced mRNA and protein expression of MUC5A C in mouse lung （ 1.672 ± 0.721 vs. 5.961 ± 2.452, t = 2.906, and 0.480 ± 0.191 vs. 2.290 ± 0.834, t = 3.665, respectively; both P 〈 0.05）. Alcian blue/periodic acid-Schiff staining also showed that CUR suppressed mucin production. Compared with the LPS group, the numbers of inflammatory cells （247 ± 30 vs. 334 ± 24, t = 3.901, P 〈 0.05） and neutrophils （185 ± 22 vs. 246 ± 20, t = 3.566, P 〈 0.05） in BALF decreased in the LPS ＋ CUR group, as well as reduced inflammatory cell infiltration in lung tissue. Conclusion： CUR inhibits LPS-induced airway mucus hypersecretion and inflammation through activation of Nrf2 possibly.
文摘Objective： To observe the effect of electroacupuncture （EA） on the expressions of acetylcholine （ACh） and mucin 5AC （MUC5AC） in the lungs of rats with chronic obstructive pulmonary disease （COPD）, and explore the mechanism of EA in treating COPD. Methods： Thirty Sprague-Dawley （SD） rats were randomly divided into a control group, a COPD group, and an EA group, with 10 rats in each group. The control group was a group of normal rats. The COPD rat model was induced by cigarette smoke combined with lipopolysaccharide （LPS）. The COPD rats were treated with EA at bilateral Feishu （BL 13） and Zusanli （ST 36） in the EA group, 30 rain each time, once a day, successively for 14 d. The lung function was tested. The contents of ACh and MUC5AC in lungs and bronchoalveolar lavage fluid （BALF） were detected by enzyme-linked immunosorbent assay （ELISA）. Pearson method was used to analyze the correlation between pulmonary function and the content of MUC5AC in lungs. The mRNA and protein expressions of MUC5AC in lung tissues were detected by real-time polymerase chain reaction （RT-PCR） and Western blot （WB）, respectively. The immune response of MUC5AC was observed by immunohistochemistry. Results： Eight rats were left in each group, and the other two died. Compared with the control group, the total airway resistance （Raw） increased significantly and dynamic compliance （Cdyn） decreased significantly in the COPD group （P〈0.01）; compared with the COPD group, the Raw level declined significantly and Cdyn increased significantly in the EA group （P〈0.01）. The contents of ACh and MUC5AC in the lungs and BALF were remarkably higher in the COPD group compared with those in the control group （P〈0.01, P〈0.001）; compared with the COPD group, the contents of ACh and MUC5AC were significantly lower in the EA group （P〈0.05, P〈0.001）. There was a negative correlation between MUC5AC content and lung function （P〈0.001）. The mRNA and protein expressions of MUC5AC in the lungs were significantly higher in the COPD group than in the control group （P〈0.001）; compared with the COPD group, the expressions were significantly lower in the EA group （P〈0.01）. Compared with the control group, the immune response of MUC5AC in the airway epithelium significantly increased in the COPD group （P〈0.001）; the immune response of MUC5AC was significantly lower in the EA group compared with that in the COPD group （P〈0.001）. Conclusion： EA treatment can improve the lung function of COPD rats, which may be related to its effect in the down-regulation of ACh and MUC5AC contents in the lungs as well as the inhibition of mucus hypersecretion.
