Ghrelin ameliorates A549 cell apoptosis caused by paraquat via p38-MAPK regulated mitochondrial apoptotic pathway
Ghrelin ameliorates A549 cell apoptosis caused by paraquat via p38-MAPK regulated mitochondrial apoptotic pathway
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DOI：
10.1016/j.tox.2019.152267
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发表时间：
2019-10-01
期刊：
影响因子：
4.5
通讯作者：
Zhang, Zhiqiang
中科院分区：
文献类型：
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作者：
Cui, Shuqing;Nian, Qing;Zhang, Zhiqiang
百草枯对人和动物有较强的危害作用，可引起急性肺损伤，死亡率较高。 Ghrelin 是一种脑肠肽，在调节各种生理过程中发挥重要作用。本研究调查了生长素释放肽是否可以抑制百草枯引起的肺损伤，并试图阐明可能的分子机制。 A549细胞与不同浓度的ghrelin预孵育，然后用200μM的PQ处理24小时。检测不同处理后A549细胞的细胞存活、凋亡、细胞氧化应激和脂质过氧化情况。随后，我们分析了 A549 细胞中的线粒体膜电位 (Delta Psi m) 并测量了 caspase-3 的激活。此外，我们研究了 MAPKs 通路的激活以及 p38-MAPK 在线粒体凋亡中的功能。我们的研究表明，施用 ghrelin 可以剂量依赖性地改善 PQ 处理的 A549 细胞的细胞活力并减少细胞凋亡。 Ghrelin 处理降低了百草枯暴露后 A549 细胞中 ROS 和 MDA 的升高，同时提高了 GSH 含量。此外，我们发现 ghrelin 剂量依赖性地增加 Delta Psi m 并降低 caspase-3 活性。磷酸化的 p38 MAPK 和 JNK 水平在 PQ 暴露后升高，而 p38 MAPK 的磷酸化在 ghrelin 预处理后降低。 p38 MAPK siRNA 或 SB203580 预处理改善了 PQ 引起的细胞损伤和凋亡相关信号，但细胞内 ROS 的产生不受影响。 N-乙酰半胱氨酸（NAC）是一种经典的抗氧化剂预处理，可降低磷酸化 p38 MAPK 水平和细胞内 ROS 产生，减轻细胞损伤并抑制细胞凋亡。结果表明，p38-MAPK 通路在 PQ 引起的肺泡上皮细胞损伤中发挥重要作用，ghrelin 可能通过抑制 ROS 诱导的 p38-MAPK 调节的线粒体凋亡通路来减轻 PQ 诱导的细胞损伤。
Paraquat has relatively strong detrimental effects on humans and animals and can cause acute lung injury with high mortality. Ghrelin is a brain-gut peptide which plays important roles in regulating various physiological processes. This study investigated whether ghrelin could inhibit paraquat-induced lung injuries and attempted to elucidate the possible molecular mechanisms. A549 cells were preincubated with different concentrations of ghrelin and then treated with 200 mu M of PQ for 24 h. Then cell survival, apoptosis, cellular oxidative stress and lipid peroxidation of A549 cells were detected after different treatments. Subsequently, we analyzed the mitochondrial membrane potential (Delta Psi m) and measured caspase-3 activation in A549 cells. In addition, we investigated the activation of the MAPKs pathway and the function of p38-MAPK within mitochondrial apoptosis. Our study indicated that ghrelin administration improved cell viability and reduced apoptosis of PQ-treated A549 cells dose-dependently. Ghrelin treatment reduced the elevation of ROS and MDA, while improved GSH content in A549 cells after paraquat exposure. Moreover, we found that ghrelin dose-dependently increased Delta Psi m and decreased caspase-3 activity. The phosphorylated p38 MAPK and JNK levels elevated following PQ exposure, while the phosphorylation of p38 MAPK decreased following ghrelin pretreatment. p38 MAPK siRNA or SB203580 pretreatment ameliorated PQ-caused cell injury and apoptosis related signals, however, the intracellular ROS production was not affected. N-Acetylcysteine (NAC), a classic antioxidant pretreatment decreased the phosphorylated p38 MAPK level and intracellular ROS production, alleviated cell injury, and inhibited apoptosis. The results showed that p38-MAPK pathway plays an important role in PQ-caused alveolar epithelial cell insult, and ghrelin might attenuate PQ-induced cell injury by inhibiting ROS-induced p38-MAPK modulated mitochondrial apoptotic pathway.