Inhibition of miR-331-3p and miR-9-5p ameliorates Alzheimer's disease by enhancing autophagy.
Inhibition of miR-331-3p and miR-9-5p ameliorates Alzheimer's disease by enhancing autophagy.
复制标题
抑制 miR-331-3p 和 miR-9-5p 可改善阿尔茨海默病
作者：
Chen ML;Hong CG;Yue T;Li HM;Duan R;Hu WB;Cao J;Wang ZX;Chen CY;Hu XK;Wu B;Liu HM;Tan YJ;Liu JH;Luo ZW;Zhang Y;Rao SS;Luo MJ;Yin H;Wang YY;Xia K;Tang SY;Xie H;Liu ZZ
阿尔茨海默病（AD）是目前仅次于心脏病和癌症的老年人第三大死亡原因。自噬随着年龄的增长而下降。我们的研究在APPswe/PS1 dE 9小鼠模型中确定了与AD进展相关的miR-331- 3 p和miR-9- 5 p的双相变化，并证明抑制miR-331- 3 p和miR-9- 5 p治疗通过促进淀粉样蛋白β（Aβ）的自噬清除来预防AD进展。研究方法：从RNA-seq数据获得microRNA的双相变化，并在早期（6个月）和晚期（12个月）APPswe/PS1 dE 9小鼠（以下简称AD小鼠）中通过qRT-PCR进行验证。采用免疫组织化学和免疫荧光染色方法检测脑组织中Aβ水平、神经元数量（MAP 2+）和活化的小胶质细胞（CD 68 + IBA 1+）。检测自噬相关基因（Becn 1、Sqstm 1、LC 3b）的mRNA和蛋白水平以确定自噬活性。采用Morris水迷宫和物体定位实验评价阿托咪对AD小鼠学习记忆能力的影响，并测定脑组织中Aβ含量。结果：miR-331- 3 p和miR-9- 5 p在AD早期表达下调，在AD晚期表达上调。我们证明了miR-331- 3 p和miR-9- 5 p分别靶向自噬受体Sequestosome 1（Sqstm 1）和Optineurin（Optn）。miR-331- 3 p和miR-9- 5 p在SH-SY 5 Y细胞系中的过表达损害自噬活性并促进淀粉样斑块形成。此外，AD小鼠在晚期接受miR-331- 3 p和miR-9- 5 p治疗后，Aβ清除率增加，认知和活动能力改善。结论：我们的研究表明，使用miR-331- 3 p和miR-9- 5 p，沿着自噬活性和淀粉样斑块可以区分早期和晚期AD，以更准确和及时地诊断。此外，我们还通过抑制miR-331- 3 p和miR-9- 5 p并增强自噬，为AD患者提供了一种可能的新治疗策略。
Alzheimer's disease (AD) is currently ranked as the third leading cause of death for eldly people, just behind heart disease and cancer. Autophagy is declined with aging. Our study determined the biphasic changes of miR-331-3p and miR-9-5p associated with AD progression in APPswe/PS1dE9 mouse model and demonstrated inhibiting miR-331-3p and miR-9-5p treatment prevented AD progression by promoting the autophagic clearance of amyloid beta (Aβ). Methods: The biphasic changes of microRNAs were obtained from RNA-seq data and verified by qRT-PCR in early-stage (6 months) and late-stage (12 months) APPswe/PS1dE9 mice (hereinafter referred to as AD mice). The AD progression was determined by analyzing Aβ levels, neuron numbers (MAP2+) and activated microglia (CD68+IBA1+) in brain tissues using immunohistological and immunofluorescent staining. MRNA and protein levels of autophagic-associated genes (Becn1, Sqstm1, LC3b) were tested to determine the autophagic activity. Morris water maze and object location test were employed to evaluate the memory and learning after antagomirs treatments in AD mice and the Aβ in the brain tissues were determined. Results: MiR-331-3p and miR-9-5p are down-regulated in early-stage of AD mice, whereas up-regulated in late-stage of AD mice. We demonstrated that miR-331-3p and miR-9-5p target autophagy receptors Sequestosome 1 (Sqstm1) and Optineurin (Optn), respectively. Overexpression of miR-331-3p and miR-9-5p in SH-SY5Y cell line impaired autophagic activity and promoted amyloid plaques formation. Moreover, AD mice had enhanced Aβ clearance, improved cognition and mobility when treated with miR-331-3p and miR-9-5p antagomirs at late-stage. Conclusion: Our study suggests that using miR-331-3p and miR-9-5p, along with autophagic activity and amyloid plaques may distinguish early versus late stage of AD for more accurate and timely diagnosis. Additionally, we further provide a possible new therapeutic strategy for AD patients by inhibiting miR-331-3p and miR-9-5p and enhancing autophagy.