应用基因敲除小鼠技术研究PSEN1调控胎盘屏障和血脑屏障的功能

PSEN1 regulates the function of the placental barrier and blood-brain barrier

目的:研究PSEN1在机体对屏障系统的调控作用。方法:构建PSEN1基因敲除小鼠,取其胎盘和大脑进行多聚甲醛固定;HE染色后观察胎盘和大脑的显微结构;免疫荧光检测大脑的血管结构;电子显微镜技术检测大脑血管超微结构。结果:PSEN1基因敲除小鼠在胚胎发育期间表现出严重的脑出血;HE染色和免疫荧光结果显示,胎盘和大脑中大血管的形成明显减少;通过UBC-Cre/ESR小鼠及他莫昔芬注射,作者获得了成年后PSEN1基因敲除小鼠,对该小鼠进行电镜超微结构观察,显示血管内皮细胞肿胀,外周支持细胞明显减少。结论:PSEN1基因敲除影响了血管外周细胞对血管内皮细胞管腔的支持,导致胎盘血管和脑血管易于出血,影响胎盘屏障和血脑屏障的功能。

Objective:To study the regulatory role of PSEN1 in the body barrier system.Methods:PSEN1 KO mice were constructed by knocking out Exon4.The placentas and brains of different genotypic mice were fixed in paraformaldehyde.HE staining and immunofluorescence were used to observe the microstructure of the vascular structure in the placenta and brain.UBC-Cre/ESR was used to knock out PSEN1 in adult mice by injection of Tamoxinfen.Electron microscopy was used to detect the ultrastructure of blood vessels in the brain of adult mice.Results:PSEN1 knock-out caused severe brain bleeding during embryonic development of the mice.HE staining and immunofluorescence showed PSEN1 knock-out resulted in a significant reduction in the formation of large blood vessels in the placenta and brain.Ultrastructure observation showed that adult-specific knock-out PSEN1 led to swelling of endothelial cells and significant reduction in external support cells in blood vessels.Conclusion:PSEN1 knock-out affects the support of extravascular cells to the endothelial cell cavities of blood vessels,causes placental and cerebrovascular blood vessels to bleed easily,and therefore affects the function of placental barrier and blood-brain barrier.