基于reelin蛋白研究先天肾虚影响脑发育的分子机制

The kidney stores essence and nourishes marrow,which is communicated to the brain .The brain is the marrow sea and the kidney is closely related with the brain. The kidney is the congenital foundation and the main driver of the body organs,so the kidney dominates the brain development.During the development of the cerebral cortex in mammals,reelin protein combines two receptors,which are very low density lipoprotein receptor and apolipoprotein E receptor 2 on the migration neurons cell membrane,Starting signal transduction system, controlling the cortical neurons of migration and corrected localization ,to maintain the developmental pattern of the mammalian neocortex from the inside to the outside. We take the reelin protein expression as the breakthrough point,and establish kidney deficiency of pregnant animal by using the method of which compound horroring stresses stimulate pregnant rats .Based on our previous results about kidney deficiency of pregnant rat,such as congenital kidney deficiency and the abnormal brain development of progeny, this study was designed to investigate the changes of reelin in signal transduction pathway during the brain development of congenital kidney deficiency progeny, to discuss the possible mechanism which of regulation of brain development by kidney ,to preliminary clarify the material basis of congenital kidney deficiency ,to provide scientific basis for the clinical treating abnormal brain development through kidney,While, enriching the theory of TCM about the kidney dominates growth and development.

肾藏精、生髓，通脑，脑为髓之海，肾脑密切相关。肾为先天之本，主司机体脏腑形体官窍生长发育，故脑发育亦由肾所主。在哺乳动物大脑皮质的发育过程中，reelin蛋白与迁移神经元细胞膜上的极低密度脂蛋白受体和载脂蛋白2型E受体结合，启动信号转导系统，控制皮质神经元的正确迁移和定位，维持哺乳动物大脑皮质由内到外的发育模式。本研究以reelin蛋白为切入点，采用以恐吓为主的复合应激刺激孕鼠，复制孕鼠肾虚模型，并予补肾填精方左归丸干预。基于我们前期肾虚孕鼠所产的子代鼠表现出先天肾虚和脑发育障碍的研究结果，本课题进一步研究先天肾虚仔鼠脑发育过程中reelin信号转导通路的变化，初步明确先天肾虚的物质基础，探讨肾调控脑发育的可能机制，同时充实中医肾主生长发育的理论，为临床脑发育障碍从肾论治提供科学依据。

在哺乳动物大脑皮质的发育过程中，Reelin蛋白与迁移神经元细胞膜上的极低密度脂蛋白受体(VLDLR)和载脂蛋白2型E受体(ApoER2)结合，启动信号转导系统，控制皮质神经元的正确迁移和定位，维持哺乳动物大脑皮质由内到外的发育模式。本研究以Reelin蛋白为切入点，采用以恐吓为主的复合应激刺激孕鼠，复制孕鼠肾虚模型，研究结果表明：模型组仔鼠平均体重下降，血清TH中的FT4含量下降，其大脑皮质区光镜下可见细胞较松散，组织结构较模糊，存在散在片状水肿，水肿区域神经细胞数目减少。电镜下模型组仔鼠大脑皮质区可见部分神经细胞出现细胞器结构异常，伴有细胞核固缩。而正常组与补肾组仔鼠大脑皮质在光学显微镜及电子显微镜下相比无明显改变。说明模型组仔鼠出现先天肾虚，同时合并脑发育障碍，而补肾中药左归丸可有效阻断先天肾虚对脑皮质发育的影响。本项目的研究目标为明确reelin信号转导通路为先天肾虚影响脑发育的分子机制。Reelin是TH 的靶分子，在实验研究中发现模型组仔鼠大脑皮质中Reelin、 VLDLR及P-DAB1蛋白表达下调，Reelin、 VLDLR及ApoER2mRNA表达下调。据此，我们推测Reelin信号通路异常与先天肾虚仔鼠大脑发育障碍有关，左归丸通过调节Reelin信号通路而阻断仔鼠大脑皮质发育障碍。