miR-181调控GABA系统基因在苯丙胺类兴奋剂所致精神障碍中的作用机制

Amphetamine-type stimulants abuse/dependence is global public health problem, 26%-46% of ATS abusers occur psychosis, which was called Amphetamine inducetd psychosis(AMP). Many previous studies have demonstrated that microRNA and dysfunction in GABAergic system play an important role in the neurobiological mechanism of ATS dependence and psychosis. But the role of microRNA and the dysfunction of GABAergic system in the amphetamine induced psychosis are not well studied. We use microRNA chip in a small samples of AMP patients, and found that miR-181 were downregulated in peripheral blood in AMP patients, and miR-181 regulates serveral genes in GABAergic system. In order to explore the mechanisims of miR-181 and their targeted gene in GABA system in the role of AMP, we will verify our preliminary findings that miR-181 are involved in AMP in an expanded sample size. Then the role of miR-181 and their regulated target gene in GABAergic system in the occurance of AMP will be explored by animal models and cellular experiment, and the targeted gene in GABAergic system will be identified. Thirdly, the mutation and genotype of miR-181 gene and their targed gene in GABAergic system in a big sample (n>=500) of patients with AMP vs ATS abusers without AMP and normal controls, will be examined to identify risk gene variance related to AMP. The AMP patients will be followed to examine the relationship among the blood level of miR-181 and genotypes of the risk genes and the outcome of AMP. The study will deepen our understand about the molecular mechanisim of miR-181 and its targeted genes in GABAergic system in the development of amphetamine induced psychosis. It will provide scientific evidences to establish biomarkers for the diagnosis，prediction and evaluation for the therapeutic effect of amphetamine induced psychosis.

苯丙胺类兴奋剂(ATS)滥用/依赖是全球性公共卫生问题，26-46%滥用者可发生精神障碍。大量研究证实microRNA及GABA系统功能损害在ATS依赖及精神障碍中起重要作用，但其在ATS所致精神障碍(AMP)中的机制研究很少。本项目组前期小样本miRNA芯片分析发现AMP患者miR-181下调，靶基因预测显示miR-181对GABA系统基因具有调控作用。本研究将扩大样本验证芯片结果；通过动物/细胞实验明确miR-181调控GABA系统基因在AMP中机制，并确定miR-181调控GABA系统的靶基因；再对大样本AMP患者的miR-181及其靶基因进行突变筛查和基因分型，探寻AMP的易感基因；对AMP患者进行随访，分析miR-181水平及易感基因与病程发展的关系。该项目可阐明miR-181调控GABA系统基因在AMP发生中的分子机制，为建立精神障碍的诊断与疗效预测及评估的生物标记提供科学依据

苯丙胺类兴奋剂(ATS)滥用/依赖是全球性公共卫生问题，26-46%滥用者可发生精神障碍。大量研究证实microRNA 及GABA 系统功能损害在ATS 依赖及精神障碍中起重要作用，但其在ATS 所致精神障碍(AMP)中的机制研究很少。我们的研究发现苯丙胺类兴奋剂使用障碍组GRIA2基因编码蛋白高于健康对照组，而GABRA1基因编码蛋白表达低于健康对照组。荧光素酶报告基因实验和Western blot实验结果表明，miR-181a负向调控GRIA2，GABRA1与miR-181a无负向调控关系。正常对照组与苯丙胺类兴奋剂使用障碍组在GABRA1基因12个SNP位点等位基因与基因型频率比较结果显示，两组中各位点等位基因与基因型频率比较未发现统计学差异。在动物模型使用METH制作CPP模型以后,发现背侧纹状体（Dorsal striatum，Dstr）的GABAAα1表达下调，GABAAα1 mRNA的表达水平没有变化。其他四个脑区（内侧前额叶皮层、伏隔核、杏仁核、背侧海马）的GABAAα1表达没有改变，其它一些常见GABAA亚型（GABAAα2、GABAAα3、GABAAα5、GABAAβ2）表达也没有改变。进一步的研究发现泛素化过程参与了METH-CPP的形成和 GABAAα1的表达下调，我们用免疫共沉淀实验和原代纹状体神经元的慢病毒干扰实验均证实泛素连接酶SYVN1参与调控了GABAAα1的表达下调。我们的研究揭示了GABA系统在苯丙胺类兴奋剂所致成瘾中的作用及相关机制，为今后治疗ATS成瘾提供了新的认知和参考。