Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

Hyperoxia-induced apoptosis of AEC Ⅱ in premature rats by inhibiting expression of focal adhesion kinase

Objective To explore the role of focal adhesion kinase (FAK) in hyperoxia-apopto- sis of type Ⅱ alveolar epithelial cells (AEC Ⅱ s) of premature rats. Methods AEC Ⅱ from prema- ture rat lungs were cultured and randomly assigned to air group and hyperoxia group. After exposed to hyperoxia for 6, 12, 24 and 48 h, apoptosis rate of AEC Ⅱ were analyzed by flow cytometry with an- nexin-Ⅴ/propidium iodine (PI) double staining. FAK mRNA and FAK and fAK-Tyr397 peptide were detected by RT-PCR and Western blot, respectively. Results Positive cells of Annexin-Ⅴ+ / PI- in AEC Ⅱ after 6,12,24 and 48 h of hyperoxia exposure were significantly decreased, and the maximal apoptosis rate of AEC Ⅱ (stained of Annexin-Ⅴ+ / PI- ) was found in the hyperoxia group at 12 h (23.83%±4.43%). Compared to the air group, the expression of FAK mRNA and of FAK de- creased markedly and progressively in hyperoxia groups at 12, 24 and 48 h(P<0. 05). Conclusions Decreased expression of FAK induced by hyperoxia is likely to contribute to the apoptosis and neco-z sis of AEC Ⅱ.     

高浓度氧通过抑制黏着斑激酶表达损伤早产大鼠肺泡Ⅱ型细胞

目的 探讨高浓度氧暴露不同时间点早产鼠肺泡Ⅱ型上皮细胞(AECⅡ)凋亡规律及其与黏着斑激酶(FAK)表达的关系.方法 原代培养早产鼠AECⅡ,暴露于高氧环境中6、12、24和48 h,并以空气组作为对照组,采用Annexin-Ⅴ和PI双标法经流式细胞仪检测AECⅡ凋亡情况,并采用Western印迹、RT-PCR技术分析AECⅡFAK多肽、磷酸化FAK(FAK-Tyr397)多肽和FAKmRNA表达变化.结果 与空气组比较,高氧暴露12 h,Annexin-Ⅴ+/PI(早期凋亡)亚群细胞所占比例最高,达(23.83±4.43)%.随高氧暴露时间延长,Annexin-Ⅴ+/PI-亚群细胞所占比例逐步减低,而Annexin-Ⅴ+/PI+亚群细胞所占比例逐步增高(P<0.05或P<0.01).AEC Ⅱ FAK、FAK-Tyr397多肽及FAK mRNA表达水平随高氧暴露时间延长呈明显下降趋势(P<0.05或P<0.01).结论 高浓度氧抑制FAK表达可能是AECⅡ凋亡和坏死的重要原因之一.     

高氧对胎鼠肺泡Ⅱ型上皮细胞生长状况的影响

目的 探讨高氧对胎鼠肺泡Ⅱ型上皮细胞(typeⅡalveolar epithelial cells,AECⅡ)的活力、生长情况、增殖和凋亡的影响. 方法 取孕19d的胎鼠肺组织,利用差速贴壁法进行AECⅡ的原代培养及纯化,将AECⅡ随机分为高氧组及空气组.空气组细胞置于5％CO2孵育箱中培养,高氧组细胞置于5％CO2 ±95％O2的混合气体孵育箱中培养.在培养的2、4、6、8d分别观察细胞的生长情况,检测细胞活力、细胞周期、细胞凋亡情况.时间点与培养组间的交互作用采用析因设计的方差分析.2组资料比较采用独立样本t检验,多组资料比较采用单因素方差分析,组间两两比较采用Bonferroni方法. 结果 (1)细胞生长状况:高氧组培养2、4、6和8d时细胞数随培养时间延长逐渐减少,分别为(7.29±0.43)×105/ml、(2.68±0.37)×105/ml、(0.23±0.10)×105/ml和(0.00±0.00)×105/ml,低于相应时间点空气组[分别为(10.41±0.24)×l05/ml、(27.90±1.91)×105/ml、(27.12±0.85)×105/ml和(26.29±1.59)×105/ml],差异均有统计学意义(t分别为10.992、38.912、94.166和49.696,P均=0.000).(2)细胞活力:高氧组在2、4、6d时细胞活力逐渐下降,活细胞率分别为(79.00±0.71)％、(52.80±1.14)％和(31.60±1.52)％,均低于相应时间点空气组,分别为(97.00±0.71)％、(97.20±0.84)％和(95.00±0.71)％,差异均有统计学意义(t分别为31.213、70.519和84.722,P均=0.000).(3)细胞周期变化:高氧组G1期和S期细胞百分率在4和6d时与2d时比较均有升高,且高于空气组,差异均有统计学意义(P＜0.05).(4)细胞凋亡变化:高氧组Annexin-V+/PI亚群在4d时所占比例最高,为(23.89±0.52)％,高于2d和6d时[(21.32±0.43)％和(1.47±0.61)％];Annexin-V+/PI+亚群细胞所占比例6d时最高,为(53.92±1.64)％,其次是4d时[(45.03±1.01)％],最低是2d时[(12.17±0.60)％];高氧组各时间点Annexin-V+/PI-和Annexin-V+/PI+亚群所占比例与对照组比较,差异均有统计学意义(P＜0.05). 结论 高氧对AECⅡ的生长、活力、增殖能力、细胞周期具有明显的抑制作用,对细胞凋亡有促进作用.