GTP环化水解酶Ⅰ/四氢生物蝶呤通路对高血压内皮祖细胞体外活性和体内再内皮化能力的调节

GTP cyclohydrolase Ⅰ/tetrahydrobiopterin pathway regulated the in-vitro function and in-vivo reendothelialization capacity of endothelial progenitor cells from hypertensive patients

目的研究GTP环化水解酶Ⅰ/四氢生物蝶呤信号通路对高血压患者循环内皮祖细胞功能的调节。方法分别纳入高血压患者和健康志愿者各19例,采集外周血进行内皮祖细胞分离、培养及鉴定,评估其迁移、增殖、黏附活性;建立裸鼠动脉损伤模型并移植高血压患者和健康志愿者内皮祖细胞,评估内皮祖细胞修复损伤血管内皮功能,并检测内皮祖细胞GTP环化水解酶Ⅰ/四氢生物蝶呤通路及一氧化氮、环磷酸鸟苷、凝血酶敏感蛋白1的mRNA表达水平。通过基因干扰、基因转染或药物阻滞干预,进一步证实该信号通路对内皮祖细胞功能的调节作用。结果高血压患者内皮祖细胞体外活性及体内再内皮化功能降低,且内皮祖细胞GTP环化水解酶Ⅰ/四氢生物蝶呤通路及其下游信号分子一氧化氮、环磷酸鸟苷的mRNA表达水平亦下降,而凝血酶敏感蛋白1 mRNA表达水平则升高。抑制该信号通路的表达可削弱内皮祖细胞的体外活性及再内皮化功能。结论研究证实GTP环化水解酶I/四氢生物蝶呤通路可通过凝血酶敏感蛋白1及可溶性鸟苷酸环化酶/环磷酸鸟苷系统调节高血压患者内皮祖细胞的体外及体内功能。

Aim To observe the regulation of GTP cyclohydrolase Ⅰ（ GTPCH Ⅰ）/tetrahydrobiopterin（ BH4）pathway on function of endothelial progenitor cells in hypertensive patients. Methods Nineteen hypertensive patients and nineteen healthy volunteers were observed. Endothelial progenitor cells were isolated from peripheral blood,cultured and identified. The in-vitro migration,proliferation,adhesion activity and in-vivo reendothelialization function of endothelial progenitor cells were detected. The model of arterial injury in nude mice was established and endothelial progenitor cells from hypertensive patients and healthy volunteers were transplanted to evaluate the reendothelialization capacity of endothelial progenitor cells. In addition,the mRNA expression of GTPCH I/BH4,and the expression of nitric oxide（ NO）,cyclic guanosine monophosphate,and thrombospondin-1（ TSP-1） mRNA levels of endothelial progenitor cells were measured. Furthermore,RNA interfection,gene transfection and drug inhibition of GTPCH I/BH4 were carried out to demonstrate its role in the regulation of endothelial progenitor cell function. Results The in-vitro migration,proliferation,adhesion activity and in-vivo reendothelialization function of endothelial progenitor cells were significantly decreased in hypertensive patients. In parallel,the expression of GTPCH I/BH4,NO and cyclic guanosine monophosphate of endothelial progenitor cells were reduced,while the TSP-1 mRNA level was elevated. When blocking the GTPCH I/BH4 pathway,the in-vitro migration,proliferation,adhesion activity and in-vivo reendothelialization function of endothelial progenitor cells from hypertensive patient and healthy volunteers were both weakened. Conclusion This study revealed that GTPCH I/BH4 pathway regulates the in-vitro and in-vivo function of endothelial progenitor cells from hypertensive patients,via regulation of TSP-1 and soluble guanylyl cyclases/cyclic guanosine monophosphate system.