ALDH1A3介导儿童孤独症系谱障碍共患重度睡眠障碍的功能与机制

More than 80% of children with autism spectrum disorders have comorbid sleep disorders (ASD-SD), but the clinical outcomes are poor.The unelucidated pathogenesis and regulatory mechanism are major obstacles to the prevention and treatment of ASD-SD.The applicant used whole transcriptome sequencing and found:ALDH1A3 was significantly down-regulated in the hippocampal neurons of temporal lobe resection for ASD-SD comorbid epilepsy，and the degree of ALDH1A3 downregulation was positively correlated to the degree of sleep disturbance. However, whether ALDH1A3 regulated ASD-SD’s sleep and the mechanism are far from clarified.Our previous studies have proved that dexmedetomidine could significantly promote sleep in ASD-SD, and further experiments have shown that dexmedetomidine could up-regulate the expression of ALDH1A3；and differential changes in nuclear receptor RORA chromatin conformation were found in ASD-SD. ALDH1A3 is known to be involved in the synthesis of retinoic acid (RA), and RA can activate the nuclear receptor RORA transcription.We speculate that ALDH1A3 mediated RA enhance the expression of nuclear receptor RORA and regulate the sleep of ASD-SD.Therefore, this project will analyze whether ALDH1A3 can regulate sleep of ASD-SD; and verify the relationship between ALDH1A3 and RORA,in order to clarify the molecular regulation mechanism of ALDH1A3 on ASD-SD.This program will provide a theoretical basis for the new therapeutic targets of ASD-SD.

高达80%孤独症系谱障碍儿童共患睡眠障碍（ASD-SD），但其治疗收效甚微。尚未阐明的发病机制是ASD-SD防治的重大障碍。申请人利用全转录组测序发现：在ASD-SD合并癫痫患儿颞叶切除海马神经元中ALDH1A3显著下调，其下调程度与睡眠障碍程度呈正相关。然而ALDH1A3是否及如何调控ASD-SD睡眠的机制远未阐明。申请人前期研究已证明右美托咪定可有效促进ASD-SD的睡眠，进一步实验表明：右美托咪定可上调ALDH1A3表达；且核受体RORA染色质构象发生差异改变。已知ALDH1A3参与合成视黄酸(RA)，而RA可激活核受体RORA转录调控睡眠。推测：ALDH1A3通过RA增强核受体RORA表达，进而改善ASD-SD的睡眠。本项目将明确ALDH1A3是否调节ASD-SD的睡眠；同时验证ALDH1A3与RORA的关系阐明其对ASD-SD的分子调控机制。为ASD-SD治疗新靶点提供理论基础。

孤独症谱系障碍(ASD)已成为全球医疗和公共卫生的危机。ASD共患睡眠障碍(SD)发生率为40-86%，影响广泛，但疗效欠佳。尚未阐明的发病及调控机制是ASD共患睡眠障碍(ASD-SD)防治的重大障碍。项目组研究发现ALDH1A3表达在ASD共患严重睡眠障碍(ASD-SD)合并癫痫儿童大脑海马神经元中显著下调，且进一步扩大队列研究样本量发现ALDH1A3的下调程度与ASD-SD的SD程度成正相关。在此基础上，项目组使用慢病毒基因技术在ASD-SD动物模型过表达或沉默ALDH1A3，证明：ALDH1A3的表达对ASD-SD小鼠模型睡眠结构和节律有显著性的影响，表现为沉默ALDH1A3后，ASD-SD模型小鼠觉醒次数增加，觉醒时间延长和非快动眼时间明显减少。这与ASD儿童队列研究的外周血ALDH1A3下调与SD程度成正相关的结果相一致。给予α2-肾上腺素受体选择性拮抗剂后，可以逆转过表达ALDH1A3对ASD-SD小鼠睡眠的影响。在孤独症行为学方面，通过旷场实验、三箱社交实验、新物体识别实验、莫里斯水迷宫实验和埋珠实验验证过表达ALDH1A3后对ASD-SD模型小鼠和ASD模型鼠的焦虑，社交，认知，记忆力和刻板行为的影响。发现过表达ALDH1A3能显著的缓解ASD-SD小鼠的焦虑症状，提高社交和认知能力，和改善记忆力和刻板行为。与ASD组相比，过表达ALDH1A3在ASD-SD组对焦虑症状，社交和认知能力，和记忆力的改善更为显著，证明ASD症状与SD可能是一个双向关系。同时，项目组进一步在ASD-SD模型小鼠模型体内实验证明，大脑海马区域核受体RORA的表达变化与ALDH1A3表达变化呈现一致性，而核受体RORA的表达上调可能依赖于α2-肾上腺素受体选择性激动作用。本项目验证和系统阐明了ALDH1A3在ASD-SD的功能与分子机制，为ASD-SD临床治疗提供可能的新干预靶点。