Qiao Peifeng, Zhao Fengli, Liu Mengjie, Gao Dan, Zhang Hua, Yan Yong
Department of Neurology, The First Affiliated Hospital of Chongqing Medical University, Chongqing 400016, P.R. China.
Mol Med Rep. 2017 Jul;16(1):971-977. doi: 10.3892/mmr.2017.6627. Epub 2017 May 25.
Hydrogen sulfide (H2S) has been demonstrated to have various effects on mitochondrial function. The aim of the present study was to investigate the effects of H2S on mitochondrial fission and the potential underlying mechanisms of these effects. Transmission electron microscopy analysis demonstrated that sodium hydrosulfide (NaHS, a donor of H2S) inhibited mitochondrial fission in a dose‑ and time‑dependent manner. Treating neuro‑2a (N2a) mouse neuroblastoma cells with 400 µM NaHS for 16 h significantly increased the % of elongated mitochondria and reduced the number of mitochondria per cell compared with untreated cells. In addition, the viability and ATP generation of N2a cells that were treated with various concentrations of NaHS was examined. The results demonstrated that treatment with 400 and 600 µM NaHS increased cell viability and ATP generation compared with untreated cells. To further understand the effects of H2S on mitochondrial morphology, the protein and mRNA expression levels of dynamin 1 like (Dnm1l, also known as Drp1) were examined, and the results demonstrated that NaHS dose‑dependently reduced Drp1 mRNA and protein levels, consistent with the mitochondrial morphology changes. To determine whether H2S affects mitochondrial morphology through Drp1 expression, Drp1 was overexpressed in N2a cells using a lentivirus encoding the Drp1 cDNA. It was observed that Drp1 overexpression reversed the effects of NaHS. Furthermore, NaHS promoted the phosphorylation of extracellular signal‑regulated kinase (ERK) 1/2, and the effects of NaHS on Drp1 expression were abolished by an ERK1/2 inhibitor (PD98059). The results of the present study indicate that the H2S‑induced decrease in Drp1 mRNA and protein levels and mitochondrial fission may involve the ERK1/2 signaling pathway. The present study suggests that H2S may be used in the future as a potential therapeutic for diseases that may be mediated by abnormal mitochondria fragmentation, such as Alzheimer's disease.
硫化氢（H₂S）已被证明对线粒体功能有多种影响。本研究的目的是探讨H₂S对线粒体分裂的影响及其潜在机制。透射电子显微镜分析表明，硫氢化钠（NaHS，一种H₂S供体）以剂量和时间依赖性方式抑制线粒体分裂。与未处理的细胞相比，用400μM NaHS处理神经-2a（N2a）小鼠神经母细胞瘤细胞16小时，显著增加了伸长线粒体的百分比，并减少了每个细胞中线粒体的数量。此外，检测了用不同浓度NaHS处理的N2a细胞的活力和ATP生成。结果表明，与未处理的细胞相比，用400和600μM NaHS处理可增加细胞活力和ATP生成。为了进一步了解H₂S对线粒体形态的影响，检测了动力蛋白1样蛋白（Dnm1l，也称为Drp1）的蛋白质和mRNA表达水平，结果表明NaHS剂量依赖性地降低了Drp1 mRNA和蛋白质水平，这与线粒体形态变化一致。为了确定H₂S是否通过Drp1表达影响线粒体形态，使用编码Drp1 cDNA的慢病毒在N2a细胞中过表达Drp1。观察到Drp1过表达逆转了NaHS的作用。此外，NaHS促进细胞外信号调节激酶（ERK）1/2的磷酸化，ERK1/2抑制剂（PD98059）消除了NaHS对Drp1表达的影响。本研究结果表明，H₂S诱导的Drp1 mRNA和蛋白质水平降低以及线粒体分裂可能涉及ERK1/2信号通路。本研究表明，H₂S未来可能作为一种潜在的治疗方法，用于治疗可能由线粒体异常碎片化介导的疾病，如阿尔茨海默病。
