Department of Life Sciences and the National Institute for Biotechnology in the Negev, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
Department of Physiology and Cell Biology, Faculty of Health Sciences and The Zlotowski Center for Neuroscience, Ben-Gurion University of the Negev, Beer-Sheva 84105, Israel.
Int J Mol Sci. 2022 Sep 1;23(17):9946. doi: 10.3390/ijms23179946.
Impaired mitochondrial function has been proposed as a causative factor in neurodegenerative diseases, including amyotrophic lateral sclerosis (ALS), caused by motor neuron degeneration. Mutations in superoxide dismutase (SOD1) cause ALS and SOD1 mutants were shown to interact with the voltage-dependent anion channel 1 (VDAC1), affecting its normal function. VDAC1 is a multi-functional channel located at the outer mitochondrial membrane that serves as a mitochondrial gatekeeper controlling metabolic and energetic crosstalk between mitochondria and the rest of the cell and it is a key player in mitochondria-mediated apoptosis. Previously, we showed that VDAC1 interacts with SOD1 and that the VDAC1-N-terminal-derived peptide prevented mutant SOD1 cytotoxic effects. In this study, using a peptide array, we identified the SOD1 sequence that interacts with VDAC1. Synthetic peptides generated from the identified VDAC1-binding sequences in SOD1 directly interacted with purified VDAC1. We also show that VDAC1 oligomerization increased in spinal cord mitochondria isolated from mutant SOD1 mice and rats. Thus, we used the novel VDAC1-specific small molecules, VBIT-4 and VBIT-12, inhibiting VDAC1 oligomerization and subsequently apoptosis and associated processes such as ROS production, and increased cytosolic Ca. VBIT-12 was able to rescue cell death induced by mutant SOD1 in neuronal cultures. Finally, although survival was not affected, VBIT-12 administration significantly improved muscle endurance in mutant SOD1 mice. Therefore, VBIT-12 may represent an attractive therapy for maintaining muscle function during the progression of ALS.
线粒体功能障碍被认为是导致神经退行性疾病的一个原因，包括肌萎缩侧索硬化症（ALS），这是由运动神经元变性引起的。超氧化物歧化酶 1（SOD1）的突变导致 ALS，并且已经表明 SOD1 突变体与电压依赖性阴离子通道 1（VDAC1）相互作用，影响其正常功能。VDAC1 是一种位于线粒体外膜的多功能通道，作为线粒体的守门员，控制线粒体与细胞其他部分之间的代谢和能量交流，它是线粒体介导的细胞凋亡的关键参与者。之前，我们已经表明 VDAC1 与 SOD1 相互作用，并且 VDAC1-N 端衍生肽可以防止突变 SOD1 的细胞毒性作用。在这项研究中，我们使用肽阵列鉴定了与 VDAC1 相互作用的 SOD1 序列。从 SOD1 中鉴定出的与 VDAC1 结合的序列生成的合成肽直接与纯化的 VDAC1 相互作用。我们还表明，突变 SOD1 小鼠和大鼠脊髓线粒体中的 VDAC1 寡聚化增加。因此，我们使用了新型的 VDAC1 特异性小分子 VBIT-4 和 VBIT-12，抑制 VDAC1 寡聚化，进而抑制细胞凋亡和相关过程，如 ROS 产生和细胞内 Ca2+增加。VBIT-12 能够挽救神经元培养物中突变 SOD1 诱导的细胞死亡。最后，虽然生存没有受到影响，但 VBIT-12 的给药显著改善了突变 SOD1 小鼠的肌肉耐力。因此，VBIT-12 可能代表一种有吸引力的治疗方法，可以在 ALS 进展过程中维持肌肉功能。
