Apoptotic signaling induced by H2O2-mediated oxidative stress in differentiated C2C12 myotubes.
Apoptotic signaling induced by H2O2-mediated oxidative stress in differentiated C2C12 myotubes.
复制标题
DOI：
10.1016/j.lfs.2009.01.014
复制
发表时间：
2009-03-27
期刊：
影响因子：
6.1
通讯作者：
Alway SE
中科院分区：
文献类型：
--
作者：
Siu PM;Wang Y;Alway SE
对有丝分裂后骨骼肌管中的凋亡信号蛋白进行了评估，以验证过氧化氢诱导的氧化应激激活分化后的C2C12肌管中caspase依赖性和非caspase依赖性凋亡蛋白的假说。我们假设氧化应激会降低C2C12肌管中抗凋亡蛋白的水平。免疫印迹法检测细胞凋亡调控因子及凋亡相关蛋白Bcl2、Bax、APAF-1、XIAP、ARC、裂解PARP、P53、p21Cip1/Waf1、c-Myc、HSP70、CuZnSOD、MnSOD蛋白含量。DNA梯状条带显示H_2O_2诱导肌管细胞凋亡，DNA片段化程度增加。细胞死亡酶联免疫吸附试验显示，过氧化氢处理后，细胞凋亡DNA片段化程度增加。4 mM H_2O_2作用24或96 h后，细胞色素c(282%，701%)、bax(56%，227%)、Smac/DIABLO(155%，260%)、caspase-3蛋白活性(51%，141%)、胞核和胞质p53(719%，1581%)表达增加。用4 mM的H_2O_2处理96h后，线粒体AIF蛋白含量增加了65%，这是线粒体AIF释放到胞浆中的一个估计。4 mM的H_2O_2作用24 h和96 h后，核蛋白组分中的AIF分别增加了74%和352%。在4 mM H_2O_2作用24 h和96 h后，bcl2在肌管中的表达分别下降了61%和69%。这些发现表明，caspase依赖和非caspase依赖的机制都参与了协调过氧化氢诱导分化的肌管细胞凋亡的激活。
Apoptotic signaling proteins were evaluated in postmitotic skeletal myotubes to test the hypothesis that oxidative stress induced by H2O2 activates both caspase-dependent and caspase-independent apoptotic proteins in differentiated C2C12 myotubes. We hypothesized that oxidative stress would decrease anti-apoptotic protein levels in C2C12 myotubes. Apoptotic regulatory factors and apoptosis-associated proteins including Bcl-2, Bax, Apaf-1, XIAP, ARC, cleaved PARP, p53, p21Cip1/Waf1, c-Myc, HSP70, CuZnSOD, and MnSOD protein content were measured by immunoblots. H2O2 induced apoptosis in myotubes as shown by DNA laddering and an elevation of apoptotic DNA fragmentation. Cell death ELISA showed increase in the extent of apoptotic DNA fragmentation following treatment with H2O2. Treatment with 4 mM of H2O2 for 24 or 96 h caused increase in Bax (56%, 227%), cytochrome c (282%, 701%), Smac/DIABLO (155%, 260%), caspase-3 protease activity (51%, 141%), and nuclear and cytosolic p53 (719%, 1581%) levels in the myotubes. As an estimate of the mitochondrial AIF release to the cytosol, AIF protein content measured in the mitochondria-free cytosolic fraction was elevated by 65% after 96 h treatment with 4 mM of H2O2. AIF measured in the nuclear protein fraction increased by 74% and 352% following treatment with 4 mM of H2O2 for 24 and 96 h, respectively. Bcl-2 declined in myotubes by 61% and 69% after 24 or 96 h of treatment in 4 mM H2O2, respectively. These findings indicate that both caspase-dependent and caspase-independent mechanisms are involved in coordinating the activation of apoptosis induced by H2O2 in differentiated myotubes.
登录
查看更多内容
影响因子：
64.8
作者：
Joza, N;Susin, SA;Penninger, JM
通讯作者：
Penninger, JM
影响因子：
5
作者：
Liu, C C;Ahearn, J M
通讯作者：
Ahearn, J M
DOI：
10.1152/ajpregu.00458.2001
发表时间：
2002-02-01
影响因子：
2.8
作者：
Dirks, A;Leeuwenburgh, C
通讯作者：
Leeuwenburgh, C
影响因子：
6
作者：
Hampton, MB;Orrenius, S
通讯作者：
Orrenius, S
影响因子：
3.9
作者：
Candé, C;Cohen, I;Kroemer, G
通讯作者：
Kroemer, G