Abstract：
The transcription factor Olig2 is highly expressed throughout oligodendroglial development and is needed for the differentiation of oligodendrocyte progenitor cells (OPCs) into oligodendrocytes and remyelination. Although Olig2 overexpression in OPCs is a possible therapeutic target for enhancing myelin repair in ischemic stroke, achieving Olig2 overexpression in vivo remains a formidable technological challenge. To address this challenge, we employed lipid nanoparticle (LNP)-mediated delivery of Olig2 synthetically modified messenger RNA (mRNA) as a viable method for in vivo Olih2 protein overexpression. Specifically, we developed CD140a-targeted LNPs loaded with Olig2 mRNA (C-Olig2) to achieve targeted Olig2 protein expression within PDGFRα+ OPCs, with the goal of promoting remyelination for ischemic stroke therapy. We show that C-Olig2 promotes the differentiation of PDGFRα+ OPCs derived from mouse neural stem cells into mature oligodendrocytes in vitro, suggesting that mRNA-mediated Olig2 overexpression is a rational approach to promote oligodendrocyte differentiation and remyelination. Furthermore, when C-Olig2 was administered to a murine model of ischemic stroke, it led to improvements in blood‒brain barrier (BBB) integrity, enhanced remyelination, and rescued learning and cognitive deficits. Our comprehensive analysis, which included bulk RNA sequencing (RNA-seq) and single-nucleus RNA-seq (snRNA-seq), revealed upregulated biological processes related to learning and memory in the brains of mice treated with C-Olig2 compared to those receiving empty LNPs (Mock). Collectively, our findings highlight the therapeutic potential of multifunctional nanomedicine targeting mRNA expression for ischemic stroke and suggest that this approach holds promise for addressing various brain diseases. STATEMENT OF SIGNIFICANCE: While Olig2 overexpression in OPCs represents a promising therapeutic avenue for enhancing remyelination in ischemic stroke, in vivo strategies for achieving Olig2 expression pose considerable technological challenges. The delivery of mRNA via lipid nanoparticles is considered aa viable approach for in vivo protein expression. In this study, we engineered CD140a-targeted LNPs loaded with Olig2 mRNA (C-Olig2) with the aim of achieving specific Olig2 overexpression in mouse OPCs. Our findings demonstrate that C-Olig2 promotes the differentiation of OPCs into oligodendrocytes in vitro, providing evidence that mRNA-mediated Olig2 overexpression is a rational strategy to foster remyelination. Furthermore, the intravenous administration of C-Olig2 into a murine model of ischemic stroke not only improved blood-brain barrier integrity but also enhanced remyelination and mitigated learning and cognitive deficits. These results underscore the promising therapeutic potential of multifunctional nanomedicine targeting mRNA expression in the context of ischemic stroke.
摘要：
转录因子Olig2在整个少突胶质细胞发育过程中高度表达，是少突胶质祖细胞（OPCs）分化为少突胶质细胞和髓鞘再生所必需的。尽管Olig2在OPCs中的过度表达是增强缺血性卒中的髓鞘修复的一个可能的治疗靶点,在体内实现Olig2过表达仍然是一项艰巨的技术挑战。为了应对这一挑战，我们采用脂质纳米颗粒（LNP）介导的Olig2合成修饰的信使RNA（mRNA）的递送作为体内Olih2蛋白过表达的可行方法。具体来说,我们开发了CD140a靶向的LNPs负载Olig2mRNA（C-Olig2），以实现PDGFRα+OPCs内的靶向Olig2蛋白表达，目的是促进缺血性卒中治疗的髓鞘再生。我们表明C-Olig2在体外促进小鼠神经干细胞来源的PDGFRα+OPCs分化为成熟的少突胶质细胞，提示mRNA介导的Olig2过表达是促进少突胶质细胞分化和髓鞘再生的合理途径。此外，当C-Olig2被用于缺血性中风的小鼠模型时，它改善了血脑屏障（BBB）的完整性，增强髓鞘再生，拯救了学习和认知缺陷。我们的综合分析，其中包括批量RNA测序（RNA-seq）和单核RNA-seq（snRNA-seq），与接受空LNP（模拟）的小鼠相比，用C-Olig2治疗的小鼠大脑中与学习和记忆有关的生物学过程上调。总的来说，我们的研究结果强调了靶向mRNA表达的多功能纳米药物治疗缺血性卒中的潜力,并提示这种方法有望解决各种脑疾病.重要声明：虽然OPCs中Olig2过度表达代表了增强缺血性卒中髓鞘再生的有希望的治疗途径，实现Olig2表达的体内策略带来了相当大的技术挑战。通过脂质纳米颗粒递送mRNA被认为是体内蛋白质表达的可行方法。在这项研究中,我们设计了载有Olig2mRNA（C-Olig2）的靶向CD140a的LNP，目的是在小鼠OPCs中实现特异性Olig2过表达。我们的研究结果表明，C-Olig2在体外促进OPCs分化为少突胶质细胞，提供证据表明mRNA介导的Olig2过表达是促进髓鞘再生的合理策略。此外，在缺血性卒中小鼠模型中静脉注射C-Olig2不仅改善了血脑屏障的完整性,而且增强了髓鞘再生,减轻了学习和认知障碍.这些结果强调了在缺血性卒中背景下靶向mRNA表达的多功能纳米药物的有希望的治疗潜力。
