从马尾藻中分离出的吲哚-6-甲醛（Mertens）Kuntze 通过激活 Nrf2/HO-1 信号通路预防氧化应激诱导的 V79-4 中国仓鼠肺成纤维细胞的细胞损伤。

Indole-6-Carboxaldehyde Isolated from Sargassum thunbergii (Mertens) Kuntze Prevents Oxidative Stress-Induced Cellular Damage in V79-4 Chinese Hamster Lung Fibroblasts through the Activation of the Nrf2/HO-1 Signaling Pathway.

机构信息

Department of Food Science and Biotechnology, College of Engineering, Kyungsung University, Busan, Republic of Korea,

Anti-Aging Research Center, Dong-eui University, Busan, Republic of Korea,

出版信息

Cell Physiol Biochem. 2020 Oct 1;54(5):959-974. doi: 10.33594/000000281.

DOI:10.33594/000000281

PMID:32997463

Abstract

BACKGROUND/AIMS: The disruption of redox equilibrium by oxidative stress, which is characterized by an overproduction of reactive oxygen species (ROS), is considered to be associated with fibroblast death in severe lung diseases. Indole-6-carboxaldehyde (I6CA) is a natural indole derivative isolated from Sargassum thunbergii, which a type of brown algae. However, the antioxidative effects of I6CA, and their mechanisms, have not been identified. This study was conducted to investigate the potential protective effects of I6CA against oxidative stress in V79-4 Chinese hamster lung fibroblasts.

METHODS

Cell viability and mechanisms related to antioxidant activity of I6CA (ROS production, cell cycle, DNA damage, mitochondrial membrane potential (MMP) and apoptosis) were studied. Western blot analysis was carried out to understand the involvement of various genes at protein level.

RESULTS

Our results demonstrated that I6CA inhibited hydrogen peroxide (HO)-induced cytotoxicity by blocking abnormal ROS accumulation. HO treatment of V79-4 fibroblasts caused cell cycle arrest at the G2/M phase, which was accompanied by increased expression of the cyclin-dependent kinase (Cdk) inhibitor p21 and decreased expression of cyclin B1 and cyclin A. However, these effects were attenuated by treatment with I6CA. I6CA also effectively protected V79-4 cells against HO-induced apoptosis by increasing the Bcl-2/Bax ratio and suppressing the loss of MMP and the cytosolic release of cytochrome c. In addition, the activation of nuclear factor-erythroid-2-related factor 2 (Nrf2) was markedly promoted by I6CA, which was associated with enhanced expression and activity of heme oxygenase-1 (HO-1). However, inhibiting the activity of HO-1 by zinc protoporphyrin IX, a potent inhibitor of HO-1, eliminated the ROS scavenging and anti-apoptotic effects of I6CA, indicating that I6CA was able to protect V79-4 lung fibroblasts from HO-induced oxidative stress by activating the Nrf2 signaling pathway.

CONCLUSION

We suggest that I6CA may be useful as a candidate therapeutic agent for the treatment of oxidative stress-related lung diseases.

摘要

背景/目的：氧化应激导致的氧化还原平衡紊乱，其特征是活性氧（ROS）的过度产生，被认为与严重肺部疾病中成纤维细胞的死亡有关。吲哚-6-甲醛（I6CA）是一种从马尾藻中分离出来的天然吲哚衍生物，属于褐藻。然而，I6CA 的抗氧化作用及其机制尚未得到确定。本研究旨在探讨 I6CA 对 V79-4 中国仓鼠肺成纤维细胞氧化应激的潜在保护作用。

方法

研究了 I6CA 的细胞活力和与抗氧化活性相关的机制（ROS 产生、细胞周期、DNA 损伤、线粒体膜电位（MMP）和细胞凋亡）。进行了 Western blot 分析以了解各种基因在蛋白质水平上的参与情况。

结果

我们的结果表明，I6CA 通过阻断异常 ROS 积累抑制过氧化氢（HO）诱导的细胞毒性。HO 处理 V79-4 成纤维细胞导致细胞周期停滞在 G2/M 期，同时 cyclin 依赖性激酶（Cdk）抑制剂 p21 的表达增加，而 cyclin B1 和 cyclin A 的表达减少。然而，这些作用被 I6CA 处理所减弱。I6CA 还通过增加 Bcl-2/Bax 比值和抑制 MMP 丧失以及细胞色素 c 的细胞质释放，有效保护 V79-4 细胞免受 HO 诱导的凋亡。此外，I6CA 显著促进核因子-红细胞 2 相关因子 2（Nrf2）的激活，这与血红素加氧酶-1（HO-1）的表达和活性增强有关。然而，用锌原卟啉 IX（一种 HO-1 的有效抑制剂）抑制 HO-1 的活性消除了 I6CA 的 ROS 清除和抗凋亡作用，表明 I6CA 通过激活 Nrf2 信号通路来保护 V79-4 肺成纤维细胞免受 HO 诱导的氧化应激。