Pulmonary fibrosis inducer, bleomycin, causes redox-sensitive activation of phospholipase D and cytotoxicity through formation of bioactive lipid signal mediator, phosphatidic acid, in lung microvascular endothelial cells.
Pulmonary fibrosis inducer, bleomycin, causes redox-sensitive activation of phospholipase D and cytotoxicity through formation of bioactive lipid signal mediator, phosphatidic acid, in lung microvascular endothelial cells.
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DOI：
10.1177/1091581810388850
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发表时间：
2011-02
影响因子：
2.2
通讯作者：
Parinandi NL
中科院分区：
文献类型：
--
作者：
Patel RB;Kotha SR;Sherwani SI;Sliman SM;Gurney TO;Loar B;Butler SO;Morris AJ;Marsh CB;Parinandi NL
已知与特发性肺纤维化（IPF）（一种使人衰弱的肺部疾病）相关的肺微血管并发症和肺动脉高压的机制尚不清楚。因此，我们研究了广泛使用的实验性 IPF 诱导剂博莱霉素是否能够在我们建立的牛肺微血管内皮细胞 (BLMVEC) 模型中激活磷脂酶 D (PLD) 并产生生物活性脂质信号介质磷脂酸 (PA)。我们的结果表明，博莱霉素以剂量依赖性（5、10 和 100 μg）和时间依赖性（2-12 小时）的方式诱导 PLD 的激活和 PA 的生成，而 PLD 特异性抑制剂 5-氟-2-吲哚基去氯卤代胺 (FIPI) 显着减弱了这种作用。博来霉素（5 μg）诱导的 PLD 活化和 PA 生成被硫醇保护剂（N-乙酰基-L-半胱氨酸）、抗氧化剂和铁螯合剂显着减弱，表明活性氧（ROS）、脂质过氧化和铁在其中的作用。此外，我们的研究证明了博莱霉素处理后细胞中ROS的形成和谷胱甘肽（GSH）的损失，证实氧化应激是博莱霉素诱导的EC中PLD激活和PA生成的关键因素。更值得注意的是，在 BLMVEC 中观察到 PLD 激活和 PA 生成发生在博来霉素诱导的细胞毒性的上游，而 BLMVEC 受到 FIPI 的保护。我们目前的研究结果也支持了这一点，即细胞暴露于外源 PA 会导致 BLMVEC 中 PA 的内化和细胞毒性。这项研究首次揭示了博来霉素诱导的 PLD 氧化还原敏感激活导致 PA 生成的新机制，PA 能够诱导肺 EC 细胞毒性，从而提示 IPF 中可能存在的生物活性脂质信号传导机制/微血管疾病机制。
The mechanisms of lung microvascular complications and pulmonary hypertension known to be associated with idiopathic pulmonary fibrosis (IPF), a debilitating lung disease, are not known. Therefore, we investigated whether bleomycin, the widely used experimental IPF inducer, would be capable of activating phospholipase D (PLD) and generating the bioactive lipid signal-mediator phosphatidic acid (PA) in our established bovine lung microvascular endothelial cell (BLMVEC) model. Our results revealed that bleomycin induced the activation of PLD and generation of PA in a dose-dependent (5, 10, and 100 μg) and time-dependent (2-12 hours) fashion that were significantly attenuated by the PLD-specific inhibitor, 5-fluoro-2-indolyl des-chlorohalopemide (FIPI). PLD activation and PA generation induced by bleomycin (5 μg) were significantly attenuated by the thiol protectant (N-acetyl-L-cysteine), antioxidants, and iron chelators suggesting the role of reactive oxygen species (ROS), lipid peroxidation, and iron therein. Furthermore, our study demonstrated the formation of ROS and loss of glutathione (GSH) in cells following bleomycin treatment, confirming oxidative stress as a key player in the bleomycin-induced PLD activation and PA generation in ECs. More noticeably, PLD activation and PA generation were observed to happen upstream of bleomycin-induced cytotoxicity in BLMVECs, which was protected by FIPI. This was also supported by our current findings that exposure of cells to exogenous PA led to internalization of PA and cytotoxicity in BLMVECs. For the first time, this study revealed novel mechanism of the bleomycin-induced redox-sensitive activation of PLD that led to the generation of PA, which was capable of inducing lung EC cytotoxicity, thus suggesting possible bioactive lipid-signaling mechanism/mechanisms of microvascular disorders encountered in IPF.
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影响因子：
9.2
作者：
Colley, WC;Sung, TC;Frohman, MA
通讯作者：
Frohman, MA
影响因子：
3.5
作者：
Magro, CM;Allen, J;Ross, P
通讯作者：
Ross, P
DOI：
10.1164/rccm.200501-017pp
发表时间：
2005-08-15
影响因子：
24.7
作者：
Kinnula, VL;Fattman, CL;Oury, TD
通讯作者：
Oury, TD
影响因子：
4.3
作者：
Cummings, R;Parinandi, N;Natarajan, V
通讯作者：
Natarajan, V
影响因子：
3.4
作者：
Brindley, DN;Waggoner, DW
通讯作者：
Waggoner, DW