DAPK1失活经脑肠轴通路诱导HSCR形成机制的研究

Hirschsprung's disease (HSCR) is the commonest congenital gut motility disorder.Currently,there are still a lot of challenges in the surgical treatment of HSCR, also there is a problem of poor living quality of patients after surgery.Brain-gut axis is the connection network between the brain and gastrointestinal ,of which the enteric nervous system (ENS) is an important part, whose developmental disorders could cause HSCR.Death-associated protein kinase 1 (DAPK1) also play an important role in the brain-gut axis .From our previous study,we found that failure of activation of DAPK1 could induced the occurrence of HSCR. In order to investigate the mechanism that the inactivation of DAPK1 induce the HSCR,the DAPK1 knockout mice and the normal mice will be regarded as research object,and various experimental techniques will be used.Firstly,we will detect the expression of DAPK1 gene in HSCR.Then,the mechanism that the inactivation of DAPK1 induced HSCR will be explored,from which the signal transduction pathway that DAPK1 influnce the development of ENS through the brain-gut axis will be established.So we can deepen the research of the pathogenesis of the HSCR,and provide a theoretical basis for the treatment of HSCR through the intervention toward the brain-gut axis,to provide a new target for the treatment of HSCR.

先天性巨结肠（HSCR）是最常见的先天性肠道运动功能紊乱性疾病。目前对HSCR的外科治疗仍存在很大的挑战，且术后病人存在生活质量不佳的问题。脑肠轴是联系大脑和胃肠道的关系网络,肠神经系统（ENS）是脑肠轴的重要环节，其发育障碍可导致HSCR。死亡相关蛋白激酶1（DAPK1）在脑肠轴中也有重要的作用，我们前期研究发现DAPK1失活可诱导小鼠产生HSCR。为了探讨DAPK1失活诱导产生HSCR的机制，本项目以DAPK1基因敲除小鼠和正常小鼠为研究对象，采用各种实验技术，首先研究HSCR中DAPK1基因的表达情况，然后探讨DAPK1失活诱导产生HSCR的机制，从而建立DAPK1通过脑肠轴影响肠神经系统发育的信号转导通路，以深化HSCR发病机制的研究，并为通过对脑肠轴的干预治疗HSCR提供理论依据，为HSCR的治疗提供新的靶点。

本课题组研究DAPK1→ERK→CREB信号通路介导DAPK1失活经脑肠轴诱导HSCR形成的相关分子机制，同时发现cdDAPK1-/-小鼠繁殖能力较差，肠道功能发育异常，生存能力较差。miRNA-214在肠道神经系统发育过程中起到关键作用，其在先天性巨结肠发生发展中的作用机制尚未明确。DAPK1调控哺乳动物胚胎发育、细胞分化、维持肿瘤干细胞活性等方面发挥着重要作用，其在结直肠癌中，特别是结直肠癌耐药与肿瘤干细胞活性，机制尚未研究清楚。我们的研究表明miRNA-214可下调PLAGL2，抑制神经嵴细胞增殖、迁移，进而参与先天性巨结肠的发生发展。在结直肠癌中，DAPK1表达下调，导致ZEB1表达量增加，进而导致结肠癌细胞的干细胞特性增强及肿瘤细胞耐药。中枢神经系统紊乱可影响肠道组织微环境平衡进而参与结直肠癌的发生发展中枢神经系统可影响肠道神经系统发育及结直肠癌的发生发展。