先天性巨结肠Neuroligin基因与纤维粘连蛋白的相关性及相互调控机制研究

Although there are many studies on the etiology of Hischsprung's disease (HD), such as "the theory of Gene-abnormality" and "the theory of intestinal microenvironmental change", the pathogenesis of HD is still not clear, which caused the difficulties of clinical diagnosis and treatment. We have preliminarily confirmed that there was a negative correlation between the expression of laminin, one important protein of the intestinal microenvironment, and the expression of RET gene, which suggested us that the pathogenesis of HD may be revealed by the correlation between "the theory of Gene-abnormality" and "the theory of intestinal microenvironmental change". And we also found that Neuroligin, which were important to the function and development of synapse and Fibronectin(another important protein of the intestinal microenvironment) had close relationship with the pathogenesis of HD. So in this study, we will discuss the correlation between "the theory of Gene-abnormality" and "the theory of intestinal microenvironmental change" on the base of the interaction of Fibronectin and Neuroligin, in order to reveal the real pathogenesis of HD and help the clinical diagnosis, treatment and prevention.

虽然先天性巨结肠(HD)的病因学研究较多，比如"基因异常学说"、"肠壁微环境变化学说"，但都不能独立地阐释其发病机制。病因不明确也导致了HD诊疗的困难。我们前期研究证实作为肠壁微环境重要物质的层粘连蛋白在HD肠壁中的表达与RET基因成负相关，预实验发现对突触有重要作用的Neuroligin基因和肠壁微环境另一重要物质纤维粘连蛋白均与HD关系密切，于是提出假说：HD的发病是"基因异常"和"肠壁微环境变化"共同作用的结果，Neuroligin与纤维粘连蛋白具有相关性和相互调控作用且与HD发病密切相关。为验证这一假说，我们将采用多种技术在人体组织、细胞和动物三个层面探讨Neuroligin与纤维粘连蛋白的相关性及相互调控机制在HD发病中的作用，从"基因异常学说"和"肠壁微环境变化学说"共同作用这一新视点为揭示HD发病机制奠定基础，为诊疗提供新的思路。

虽然先天性巨结肠(HD)的病因学研究较多，比如“基因异常学说”、“肠壁微环境变化学说”，但都不能独立地阐释其发病机制。病因不明确也导致了HD诊疗的困难。我们前期研究证实作为肠壁微环境重要物质的层粘连蛋白在HD肠壁中的表达与RET基因成负相关关系，即“基因异常学说”和“肠壁微环境变化学说”具有相关性，于是提出假说：HD的发病可能是“基因异常”和“肠壁微环境变化”共同作用的结果。在本次实验中，通过对巨结肠患者肠道组织标本的研究，证实在狭窄段、移行段和扩张段三部分，neuroligin-1（NL1）和neuroligin-2（NL2）的蛋白和基因表达量分别呈现递增趋势，而fibronectin（FN）的表达量则呈现递减趋势。通过对巨结肠患儿和非巨结肠患儿血清标本的研究，证实FN在先天性巨结肠患儿血清中的含量明显低于对照组患儿的血清含量。与此同时，在实验动物胚胎的检测中，我们发现随着胚胎发育时间的增长，肠神经系统的神经节细胞中NLs的表达量逐渐增加，而FN则逐渐减少。在细胞实验中对293T和PC12细胞分别实施过表达和下调FN、NL1和NL2处理，证实FN与NL1和NL2表达水平呈负相关，并且通过添加不同浓度梯度的可溶性蛋白刺激，进一步证实三者间存在线性负相关。肠神经系统发育的不完善导致了儿童HD的发病，我们的发现证实了肠壁微环境的变化可导致肠神经系统神经节异常发育，为进一步阐释HD发病机制提供科学依据。