Department of Pharmaceutical Sciences, College of Pharmacy, Robertson Life Sciences Building, Oregon State University, Portland, OR 97201, USA.
Department of Pediatrics, School of Medicine, Oregon Health & Science University, Portland, OR 97239, USA.
Sci Adv. 2020 Nov 18;6(47). doi: 10.1126/sciadv.abc5911. Print 2020 Nov.
Cystic fibrosis (CF) results from mutations in the chloride-conducting () gene. Airway dehydration and impaired mucociliary clearance in CF is proposed to result in tonic epithelial sodium channel (ENaC) activity, which drives amiloride-sensitive electrogenic sodium absorption. Decreasing sodium absorption by inhibiting ENaC can reverse airway surface liquid dehydration. Here, we inhibit endogenous heterotrimeric ENaC channels by introducing inactivating mutant ENaC α mRNA (αENaC). Lipid nanoparticles carrying αENaC were transfected in CF-based airway cells in vitro and in vivo. We observed a significant decrease in macroscopic as well as amiloride-sensitive ENaC currents and an increase in airway surface liquid height in CF airway cells. Similarly, intranasal transfection of αENaC mRNA decreased amiloride-sensitive nasal potential difference in KO mice. These data suggest that mRNA-based ENaC inhibition is a powerful strategy for reducing mucus dehydration and has therapeutic potential for treating CF in all patients, independent of genotype.
囊性纤维化（CF）是由氯离子通道（）基因的突变引起的。CF 中的气道脱水和黏液纤毛清除受损被认为导致紧张性上皮钠通道（ENaC）活性，从而驱动阿米洛利敏感的电致钠吸收。通过抑制 ENaC 来减少钠吸收可以逆转气道表面液体的脱水。在这里，我们通过引入失活的突变 ENaCαmRNA（αENaC）来抑制内源性三聚体 ENaC 通道。携带αENaC 的脂质纳米颗粒在体外和体内转染基于 CF 的气道细胞。我们观察到 CF 气道细胞中的宏观以及阿米洛利敏感的 ENaC 电流显著减少，气道表面液体高度增加。同样，αENaC mRNA 的鼻内转染降低了 KO 小鼠中阿米洛利敏感的鼻电位差。这些数据表明，基于 mRNA 的 ENaC 抑制是减少黏液脱水的有效策略，并且具有治疗所有患者 CF 的治疗潜力，与基因型无关。
