Morales Fernando, Vargas Dayana, Palma-Jiménez Melissa, Rodríguez Esteban J, Azofeifa Gabriela, Hernández-Hernández Oscar
Instituto de Investigaciones en Salud (INISA), Universidad de Costa Rica, San José 2060, Costa Rica.
Departamento de Bioquímica, Escuela de Medicina, Universidad de Costa Rica, San José 2060, Costa Rica.
Antioxidants (Basel). 2025 Feb 25;14(3):260. doi: 10.3390/antiox14030260.
The toxic gain-of-function of RNA-CUG in DM1 has been largely studied in skeletal muscle, with little focus on its effects on the central nervous system (CNS). This study aimed to study if oxidative stress is present in DM1, its relationship with the toxic RNA gain-of-function and if natural antioxidants can revert some of the RNA-CUG toxic effects. Using an inducible glial DM1 model (MIO-M1 cells), we compared OS in expanded vs. unexpanded cells and investigated whether antioxidants can mitigate OS and RNA-CUG toxicity. OS was measured via superoxide anion and lipid peroxidation assays. RNA foci were identified using FISH, and the mis-splicing of selected exons was analyzed using semi-quantitative RT-PCR. Cells were treated with natural antioxidants, and the effects on OS, foci formation, and mis-splicing were compared between treated and untreated cells. The results showed significantly higher superoxide anion and lipid peroxidation levels in untreated DM1 cells, which decreased after antioxidant treatment (ANOVA, < 0.001). Foci were present in 51% of the untreated cells but were reduced in a dose-dependent manner following treatment (ANOVA, < 0.001). Antioxidants also improved the splicing of selected exons (ANOVA, < 0.001), suggesting OS plays a role in DM1, and antioxidants may offer therapeutic potential.
RNA-CUG在强直性肌营养不良1型（DM1）中的毒性功能获得主要在骨骼肌中进行了研究，很少关注其对中枢神经系统（CNS）的影响。本研究旨在探讨DM1中是否存在氧化应激，其与毒性RNA功能获得的关系，以及天然抗氧化剂是否可以逆转部分RNA-CUG的毒性作用。使用诱导性神经胶质DM1模型（MIO-M1细胞），我们比较了扩增细胞与未扩增细胞中的氧化应激，并研究了抗氧化剂是否可以减轻氧化应激和RNA-CUG毒性。通过超氧阴离子和脂质过氧化测定法测量氧化应激。使用荧光原位杂交（FISH）鉴定RNA病灶，并使用半定量逆转录聚合酶链反应（RT-PCR）分析选定外显子的错配剪接。用天然抗氧化剂处理细胞，并比较处理组和未处理组细胞对氧化应激、病灶形成和错配剪接的影响。结果显示，未处理的DM1细胞中超氧阴离子和脂质过氧化水平显著更高，抗氧化剂处理后降低（方差分析，P<0.001）。51%的未处理细胞中存在病灶，但处理后呈剂量依赖性减少（方差分析，P<0.001）。抗氧化剂还改善了选定外显子的剪接（方差分析，P<0.001），表明氧化应激在DM1中起作用，抗氧化剂可能具有治疗潜力。
