Kotowska-Zimmer Anna, Przybyl Lukasz, Pewinska Marianna, Suszynska-Zajczyk Joanna, Wronka Dorota, Figiel Maciej, Olejniczak Marta
Department of Genome Engineering, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
Laboratory of Mammalian Model Organisms, Institute of Bioorganic Chemistry, Polish Academy of Sciences, Noskowskiego 12/14, 61-704 Poznan, Poland.
Mol Ther Nucleic Acids. 2022 May 5;28:702-715. doi: 10.1016/j.omtn.2022.04.031. eCollection 2022 Jun 14.
Among the many proposed therapeutic strategies for Huntington's disease (HD), allele-selective therapies are the most desirable but also the most challenging. RNA interference (RNAi) tools that target CAG repeats selectively reduce the mutant huntingtin level in cellular models of HD. The purpose of this study was to test the efficacy, selectivity, and safety of two vector-based RNAi triggers in an animal model of HD. CAG repeat-targeting short hairpin RNA (shRNA) and artificial miRNA (amiRNA) were delivered to the brains of YAC128 mice via intrastriatal injection of AAV5 vectors. Molecular tests demonstrated that both the shRNA and amiRNA reduced the mutant huntingtin level by 50% without influencing endogenous mouse huntingtin. In addition, a concentration-dependent reduction in HTT aggregates in the striatum was observed. In contrast to the shRNA, the amiRNA was well tolerated and did not show signs of toxicity during the course of the experiment up to 20 weeks post injection. Interestingly, amiRNA treatment reduced the spleen weight to values characteristic of healthy (WT) mice and improved motor performance on the static rod test. These preclinical data demonstrate that the CAG-targeting strategy and amiRNA could make an original and valuable contribution to currently used therapeutic approaches for HD.
在众多针对亨廷顿舞蹈病（HD）提出的治疗策略中，等位基因选择性疗法是最理想的，但也是最具挑战性的。靶向CAG重复序列的RNA干扰（RNAi）工具可在HD细胞模型中选择性降低突变型亨廷顿蛋白水平。本研究的目的是在HD动物模型中测试两种基于载体的RNAi触发剂的疗效、选择性和安全性。通过向YAC128小鼠脑内纹状体注射AAV5载体，将靶向CAG重复序列的短发夹RNA（shRNA）和人工微小RNA（amiRNA）递送至小鼠脑内。分子检测表明，shRNA和amiRNA均使突变型亨廷顿蛋白水平降低了50%，而不影响内源性小鼠亨廷顿蛋白。此外，观察到纹状体中HTT聚集体呈浓度依赖性减少。与shRNA不同，amiRNA耐受性良好，在注射后长达20周的实验过程中未表现出毒性迹象。有趣的是，amiRNA治疗使脾脏重量降至健康（野生型）小鼠的特征值，并改善了静态杆试验中的运动性能。这些临床前数据表明，靶向CAG的策略和amiRNA可为目前用于HD的治疗方法做出独特而有价值的贡献。
