Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue ev...Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue even after birth. In addition to type I cells which form the blood-air barrier, type II alveolar epithelial (AE) cells have important and diverse functions related to immunological protection and stabilization of the alveolus through synthesis and secretion of the pulmonary surfactant. Apoptosis or programmed cells death is an important physiological process during lung embryogenesis and for the proper maintenance of homeostasis. Caspases are proteases that play important roles in regulating apoptosis. Caspase-3 is the key executioner caspase in the cascade of events leading to cell death by apoptosis. We explored the hypothesis that cigarette smoke extract (CSE) induces apoptosis in fetal rat lung type II AE cells by activation of caspase-3. To analyze these factors, isolated fetal rat lung type II AE cells were used. The cells were exposed to different concentrations of CSE (5%, 10% or 15%) (v/v) for 60 min. The results of the present study showed that CSE induced apoptosis in fetal rat lung type II AE cells with a significant increase (p 0.05) in caspase-3 activity and decrease in cell proliferation at CSE concentrations of 10% and 15% (v/v). These observations indicate that cigarette smoke extract induces apoptosis by activation of caspase-3 in fetal rat lung type II AE cells in a dose-dependent manner and may potentially alter the regulated development of the lung and the appearance of the surfactant-producing type II alveolar cells which are critical for the establishment of adequate gas exchange at birth.展开更多
目的探讨p38丝裂原活化蛋白激酶(p38MAPK)抑制剂SB203580对妊娠晚期合并急性胰腺炎(acute pancreatitis in late pregnancy,APILP)相关胎鼠肺脏损伤中的作用及可能机制。方法24只SPF级妊娠晚期SD大鼠随机(随机数字法)分为假手术(Sham-op...目的探讨p38丝裂原活化蛋白激酶(p38MAPK)抑制剂SB203580对妊娠晚期合并急性胰腺炎(acute pancreatitis in late pregnancy,APILP)相关胎鼠肺脏损伤中的作用及可能机制。方法24只SPF级妊娠晚期SD大鼠随机(随机数字法)分为假手术(Sham-operation,SO)组、APILP组和p38MAPK抑制剂SB203580处理(SB)组。采用5%牛磺胆酸钠(sodium taurocholate,STC)逆行胰胆管注射法建立APILP模型,SB组大鼠在建立APILP模型前0.5 h给予SB203580腹腔注射(10 mg/kg)。SO组大鼠仅在开腹后翻动暴露胰腺。SO和APILP组大鼠在开腹前0.5 h给予对应体积的SB203580溶剂,各组大鼠均在术后12 h剖杀取材。测定大鼠AMY和TNF-α水平,光镜下观察大鼠胰腺、胎鼠肺脏的病理学改变,并进行评分。免疫组织化学法检测胎鼠肺脏中NF-κB的表达及定位,免疫荧光法检测胎鼠肺脏中MPO的表达,免疫印迹法检测胎鼠肺脏中p-p38MAPK、p38MAPK、TNF-α、细胞间黏附分子-1(ICAM-1)以及高迁移率族蛋白1 (high mobility group box-1 protein, HMGB1)的表达水平。单因素方差分析进行统计学处理,组间比较采用Tukey事后多重比较,以P<0.05为差异具有统计学意义。结果与SO组相比,APILP组妊娠大鼠血清中AMY、TNF-α的水平显著升高[(7 871.3±623.5) vs (1 915.3±452.3),(193.8±25.4) vs (107.0±13.3),(P<0.05)],APILP组大鼠胰腺、胎鼠肺脏的病理评分显著增高[(12.44±1.08) vs (1.56±0.56),(2.50±0.53) vs (0.88±0.64),(P<0.05)],胎鼠肺脏中NF-κB、MPO阳性细胞计数显著多于SO组[(150.63±34.58) vs (29.50±8.80),(53.38±8.30) vs (11.75±3.33),(P<0.05)],并且NF-κB的表达量和核转位更为明显;ANPIP组胎鼠肺脏中p-p38MAPK[(0.6367±0.0386) vs (0.2282±0.0220)]、TNF-α[(0.6313±0.0395) vs (0.0725±0.0076)]、ICAM-1[(0.8958±0.0776) vs (0.1372±0.0388)]和HMGB1[(0.6478±0.0209) vs (0.2825±0.0533)]的表达水平显著升高(P<0.05)。与APILP组比较,SB组妊娠大鼠血清中AMY(4,162.1±642.1)、TNF-α(139.6±21.1)水平显著下降(P<0.05),妊娠大鼠胰腺(9.38±1.58)和胎鼠肺脏(1.63±0.52)的病理评分显著降低(P<0.05),胎鼠肺脏中NF-κB(93.00±18.88)和MPO(27.38±4.75)阳性细胞计数显著下降(P<0.05),并且NF-κB表达量和核转位水平明显减少,胎鼠肺脏中p-p38MAPK(0.2578±0.0170)、TNF-α(0.3240±0.0326)、ICAM-1(0.4177±0.0823)和HMGB1(0.4923±0.0457)的表达水平显著下降(P<0.05)。结论p38MAPK及其下游炎症信号通路参与了APILP相关胎鼠肺脏损伤的过程;SB203580干预能够显著改善APILP相关胎鼠肺脏损伤,其机制可能与其抑制p38MAPK的磷酸化水平,阻断其下游信号通路激活引起的炎症级联反应有关。展开更多
【目的】探讨孕期亚临床维生素A(vitamin A,VA)缺乏对胎鼠肺形态发育的影响。【方法】建立孕期VA正常(vitamin A normal,VAN)和亚临床缺乏(marginal vitamin A deficiency,MVAD)动物模型,每组均于孕19d剖宫取胎鼠,比较其体重、肺重、肝...【目的】探讨孕期亚临床维生素A(vitamin A,VA)缺乏对胎鼠肺形态发育的影响。【方法】建立孕期VA正常(vitamin A normal,VAN)和亚临床缺乏(marginal vitamin A deficiency,MVAD)动物模型,每组均于孕19d剖宫取胎鼠,比较其体重、肺重、肝重和肺组织VA含量及其肺视黄酸受体(retinoic acid receptor,RAR)mRNAs的表达,HE染色光镜观察胎鼠肺的形态结构。【结果】1)胎鼠基本情况的比较体重、肺重和肝重三个指标VAN组均显著高于MVAD组(P<0.05);2)胎肺大体形态比较低倍镜(×200)与高倍镜(×400)下观察结果显示,VAN组肺泡样结构分布较规则,肺泡间隔较薄,肺实质发育较好,肺间质毛细血管较丰富,肺泡2型细胞较明显,大多处于小管期;而MVAD组上述指标均相对较差,发育幼稚,局部为小管期,大多为假腺体期;3)胎鼠肺单位组织VA水平VAN组>MVAD组,差异均有统计学意义(P<0.05);4)胎鼠肺RAR-α、RAR-γ和RAR-βmRNAs表达水平VAN组<MVAD组,三个基因的表达水平两组比较差异均有统计学意义(P<0.05)。【结论】孕期VA水平不同能影响胎鼠基本发育、胎肺形态结构、肺单位组织VA水平及其RAR mRNAs的表达;孕期MVAD时其胎肺发育相对较差。展开更多
文摘Smoking during pregnancy is a major source of fetal exposure to numerous harmful agents present in tobacco smoke. Lung development involves complex biochemical processes resulting in dramatic changes which continue even after birth. In addition to type I cells which form the blood-air barrier, type II alveolar epithelial (AE) cells have important and diverse functions related to immunological protection and stabilization of the alveolus through synthesis and secretion of the pulmonary surfactant. Apoptosis or programmed cells death is an important physiological process during lung embryogenesis and for the proper maintenance of homeostasis. Caspases are proteases that play important roles in regulating apoptosis. Caspase-3 is the key executioner caspase in the cascade of events leading to cell death by apoptosis. We explored the hypothesis that cigarette smoke extract (CSE) induces apoptosis in fetal rat lung type II AE cells by activation of caspase-3. To analyze these factors, isolated fetal rat lung type II AE cells were used. The cells were exposed to different concentrations of CSE (5%, 10% or 15%) (v/v) for 60 min. The results of the present study showed that CSE induced apoptosis in fetal rat lung type II AE cells with a significant increase (p 0.05) in caspase-3 activity and decrease in cell proliferation at CSE concentrations of 10% and 15% (v/v). These observations indicate that cigarette smoke extract induces apoptosis by activation of caspase-3 in fetal rat lung type II AE cells in a dose-dependent manner and may potentially alter the regulated development of the lung and the appearance of the surfactant-producing type II alveolar cells which are critical for the establishment of adequate gas exchange at birth.
文摘目的探讨p38丝裂原活化蛋白激酶(p38MAPK)抑制剂SB203580对妊娠晚期合并急性胰腺炎(acute pancreatitis in late pregnancy,APILP)相关胎鼠肺脏损伤中的作用及可能机制。方法24只SPF级妊娠晚期SD大鼠随机(随机数字法)分为假手术(Sham-operation,SO)组、APILP组和p38MAPK抑制剂SB203580处理(SB)组。采用5%牛磺胆酸钠(sodium taurocholate,STC)逆行胰胆管注射法建立APILP模型,SB组大鼠在建立APILP模型前0.5 h给予SB203580腹腔注射(10 mg/kg)。SO组大鼠仅在开腹后翻动暴露胰腺。SO和APILP组大鼠在开腹前0.5 h给予对应体积的SB203580溶剂,各组大鼠均在术后12 h剖杀取材。测定大鼠AMY和TNF-α水平,光镜下观察大鼠胰腺、胎鼠肺脏的病理学改变,并进行评分。免疫组织化学法检测胎鼠肺脏中NF-κB的表达及定位,免疫荧光法检测胎鼠肺脏中MPO的表达,免疫印迹法检测胎鼠肺脏中p-p38MAPK、p38MAPK、TNF-α、细胞间黏附分子-1(ICAM-1)以及高迁移率族蛋白1 (high mobility group box-1 protein, HMGB1)的表达水平。单因素方差分析进行统计学处理,组间比较采用Tukey事后多重比较,以P<0.05为差异具有统计学意义。结果与SO组相比,APILP组妊娠大鼠血清中AMY、TNF-α的水平显著升高[(7 871.3±623.5) vs (1 915.3±452.3),(193.8±25.4) vs (107.0±13.3),(P<0.05)],APILP组大鼠胰腺、胎鼠肺脏的病理评分显著增高[(12.44±1.08) vs (1.56±0.56),(2.50±0.53) vs (0.88±0.64),(P<0.05)],胎鼠肺脏中NF-κB、MPO阳性细胞计数显著多于SO组[(150.63±34.58) vs (29.50±8.80),(53.38±8.30) vs (11.75±3.33),(P<0.05)],并且NF-κB的表达量和核转位更为明显;ANPIP组胎鼠肺脏中p-p38MAPK[(0.6367±0.0386) vs (0.2282±0.0220)]、TNF-α[(0.6313±0.0395) vs (0.0725±0.0076)]、ICAM-1[(0.8958±0.0776) vs (0.1372±0.0388)]和HMGB1[(0.6478±0.0209) vs (0.2825±0.0533)]的表达水平显著升高(P<0.05)。与APILP组比较,SB组妊娠大鼠血清中AMY(4,162.1±642.1)、TNF-α(139.6±21.1)水平显著下降(P<0.05),妊娠大鼠胰腺(9.38±1.58)和胎鼠肺脏(1.63±0.52)的病理评分显著降低(P<0.05),胎鼠肺脏中NF-κB(93.00±18.88)和MPO(27.38±4.75)阳性细胞计数显著下降(P<0.05),并且NF-κB表达量和核转位水平明显减少,胎鼠肺脏中p-p38MAPK(0.2578±0.0170)、TNF-α(0.3240±0.0326)、ICAM-1(0.4177±0.0823)和HMGB1(0.4923±0.0457)的表达水平显著下降(P<0.05)。结论p38MAPK及其下游炎症信号通路参与了APILP相关胎鼠肺脏损伤的过程;SB203580干预能够显著改善APILP相关胎鼠肺脏损伤,其机制可能与其抑制p38MAPK的磷酸化水平,阻断其下游信号通路激活引起的炎症级联反应有关。
文摘【目的】探讨孕期亚临床维生素A(vitamin A,VA)缺乏对胎鼠肺形态发育的影响。【方法】建立孕期VA正常(vitamin A normal,VAN)和亚临床缺乏(marginal vitamin A deficiency,MVAD)动物模型,每组均于孕19d剖宫取胎鼠,比较其体重、肺重、肝重和肺组织VA含量及其肺视黄酸受体(retinoic acid receptor,RAR)mRNAs的表达,HE染色光镜观察胎鼠肺的形态结构。【结果】1)胎鼠基本情况的比较体重、肺重和肝重三个指标VAN组均显著高于MVAD组(P<0.05);2)胎肺大体形态比较低倍镜(×200)与高倍镜(×400)下观察结果显示,VAN组肺泡样结构分布较规则,肺泡间隔较薄,肺实质发育较好,肺间质毛细血管较丰富,肺泡2型细胞较明显,大多处于小管期;而MVAD组上述指标均相对较差,发育幼稚,局部为小管期,大多为假腺体期;3)胎鼠肺单位组织VA水平VAN组>MVAD组,差异均有统计学意义(P<0.05);4)胎鼠肺RAR-α、RAR-γ和RAR-βmRNAs表达水平VAN组<MVAD组,三个基因的表达水平两组比较差异均有统计学意义(P<0.05)。【结论】孕期VA水平不同能影响胎鼠基本发育、胎肺形态结构、肺单位组织VA水平及其RAR mRNAs的表达;孕期MVAD时其胎肺发育相对较差。
