腹外侧眶皮层microRNA调控MKPs在抑郁症中的作用研究

microRNA (miRNA) regulation of gene expression plays an important role in the depression. According to the recent studies and our previous works, mitogerr activated protein kinase phosphotases (MKPs) are significantly associated with depression.The ventrolateral orbital cortex (VLO), which is a critical nucleus in mediating emotional regulation. The MKP-targeted miRNA and its mechanism in regulating depression within VLO has not been clarified. In the present study, we will use a rats depression model of chronic unpredictable stress (CUS) to determine the levels of MKPs mRNA and protein expression in VLO. Using RNA interference to inhibit MKP expression within the VLO, According to the results of behavior and molecular tests, clarify the role of MKP in depressionin in vivo; By in vivo and in vitro experiments, microRNAs which is target regulation key MKPs, will be screened and identifid. VLO injection of the microRNA mimic or inhibitors, combination with behavior and molecular results, evaluation of microRNA antidepressant effect. Finally clarify the mechanism of miRNA regulated-MKPs within the VLO on the development and pathogenesis of depression. It is hoped that, by revealing the mechanism of miRNA regulated-MKP in depression, we can provide experimental evidence for the regulatory mechanism of depression and develop new therapeutic opportunities.

microRNA(miRNA)调控基因表达在抑郁症中具有重要作用。最新研究及我们前期的工作表明，丝裂原活化蛋白激酶磷酸酶(MKPs)与抑郁症显著关联。腹外侧眶皮层(VLO)作为介导情感调控的关键核团，其神经元内miRNA调控哪些MKP分子，其在抑郁症中的具体作用机制尚不明确。本研究通过慢性不可预知应激建立大鼠抑郁症模型，获得抑郁大鼠VLO内MKPs表达谱，利用RNA干扰下调VLO内关键MKP表达，体内验证MKP对抑郁症的调控作用；通过体内、体外实验筛选并确定靶向调控MKP的miRNA，VLO内注射miRNA类似物或抑制剂，对照临床抗抑郁药物评估miRNA抗抑郁效果，最终阐明VLO内miRNA调控MKP在抑郁症发病、发展中的作用机制。本课题不仅为miRNA及关键MKP在抑郁症中的调控机制提供实验证据，也为miRNA相关新型抗抑郁药物开发提供理论基础。

项目背景：microRNA (miRNA)调控基因表达在抑郁症中具有重要作用。最新研究及我们前期的工作表明，丝裂原活化蛋白激酶磷酸酶(MKPs)与抑郁症显著关联。腹外侧眶皮层(VLO)作为介导情感调控的关键核团，其神经元内miRNA调控哪些MKP分子，其在抑郁症中的具体作用机制尚不明确。.研究内容：本研究通过慢性不可预知应激建立大鼠抑郁症模型，获得抑郁大鼠VLO内MKPs表达谱，利用RNA干扰下调VLO内关键MKP表达，体内验证MKP对抑郁症的调控作用；通过体内、体外实验筛选并确定靶向调控MKP的miRNA，VLO内注射miRNA类似物或抑制剂，对照临床抗抑郁药物评估miRNA抗抑郁效果，阐明VLO内miRNA调控MKP在抑郁症发病、发展中的作用机制。.结果及关键数据：本研究发现：CUS不影响大鼠活动能力及焦虑状态，可诱导大鼠产生抑郁样行为，包括典型的快感缺乏及行为绝望，证明CUS处理可建立大鼠抑郁症模型；VLO参与调控大鼠抑郁样行为。VLO损毁不影响大鼠情景记忆、活动能力，但显著降低大鼠抑郁样行为；抑郁症大鼠VLO内DUSP1、PAC1、Mkp-2、DUSP5、Mkp-X、Mkp-5表达升高，提示大鼠VLO内这些分子可能参与调控抑郁样行为，且以DUSP1、DUSP5、Mkp-X表达改变最为显著；慢性应激性环境所致抑郁样为与VLO内DUSP1-pERK下调有关，miR-200、miR-101可直接下调VLO内DUSP1表达，提高pERK表达并最终改善抑郁症状。在CUS流程进行前、后分别在VLO内微量注射靶向调控DUSP1分子的miRNA类似物或抑制物，对比临床常用抗抑郁药物如氟西汀，观察对抑郁行为的影响，对miRNA与传统抗抑郁药疗效进行分析比较。.科学意义：本课题筛选出VLO内调控抑郁样行为的关键miRNA：miR-200和miR-101。不仅为miRNA及关键MKPs在抑郁症中的调控机制提供了新的实验证据，也为miRNA相关新型抗抑郁药物开发提供了理论基础。