CAJ | 학술논문

目的探讨人脑胶质瘤血脑屏障(BBB)内皮细胞间紧密连接的变化及其可能的分子机制. 方法将南方医科大学珠江医院神经外科自2008年至2009年切除的胶质瘤和正常脑组织标本分为3组:正常脑组织组(n=6)、低级别胶质瘤组(n=11)与高级别胶质瘤组(n=10),采用透射电镜观察标本BBB紧密连接的超微结构特征,应用免疫荧光双标染色和RT-PCR分别检测标本紧密连接蛋白Claudin-5和Claudin-5 mRNA的表达. 结果电镜结果显示正常脑组织微血管相邻内皮细胞间可见连续条带状的紧密连接.细胞间未见裂隙.低级别胶质瘤中多数微血管内皮细胞间可见连续的紧密连接,未见明显窗口形成.高级别胶质瘤中微血管内皮细胞间紧密连接破坏严重,内皮细胞间可见明显裂隙;免疫荧光双标染色结果显示正常脑组织中微血管内皮细胞上有大量Claudin-5表达.低级别胶质瘤中微血管内皮细胞上Claudin-5表达略为下降,而高级别胶质瘤中微血管内皮细胞上无明显Clandin-5表达;RT-PCR结果显示高级别胶质瘤Claudin-5 mRNA表达低于正常组脑组织和低级别胶质瘤,差异有统计学意义(P<0.05). 结论在脑胶质瘤发生发展过程中.胶质瘤细胞可以导致BBB内皮细胞间紧密连接蛋白Claudin-5的表达下降及BBB紧密连接结构的破坏,而紧密连接蛋白Claudin-5这一分子元件的表达下降可能是紧密连接结构受到破坏的重要分子机制.
목적 탐토인뇌효질류혈뇌병장(BBB)내피세포간긴밀련접적변화급기가능적분자궤제. 방법 장남방의과대학주강의원신경외과자2008년지2009년절제적효질류화정상뇌조직표본분위3조:정상뇌조직조(n=6)、저급별효질류조(n=11)여고급별효질류조(n=10),채용투사전경관찰표본BBB긴밀련접적초미결구특정,응용면역형광쌍표염색화RT-PCR분별검측표본긴밀련접단백Claudin-5화Claudin-5 mRNA적표체. 결과 전경결과 현시정상뇌조직미혈관상린내피세포간가견련속조대상적긴밀련접.세포간미견렬극.저급별효질류중다수미혈관내피세포간가견련속적긴밀련접,미견명현창구형성.고급별효질류중미혈관내피세포간긴밀련접파배엄중,내피세포간가견명현렬극;면역형광쌍표염색결과 현시정상뇌조직중미혈관내피세포상유대량Claudin-5표체.저급별효질류중미혈관내피세포상Claudin-5표체략위하강,이고급별효질류중미혈관내피세포상무명현Clandin-5표체;RT-PCR결과 현시고급별효질류Claudin-5 mRNA표체저우정상조뇌조직화저급별효질류,차이유통계학의의(P<0.05). 결론 재뇌효질류발생발전과정중.효질류세포가이도치BBB내피세포간긴밀련접단백Claudin-5적표체하강급BBB긴밀련접결구적파배,이긴밀련접단백Claudin-5저일분자원건적표체하강가능시긴밀련접결구수도파배적중요분자궤제.
Objective To investigate the changes and the molecular mechanism of tight junctions of blood-brain barrier (BBB) in human glioma. Methods A retrospective analysis was conducted in 21 patients with glioma of different grades and 6 healthy adults and thus we divided them into normal tissue group (n=6), low-grade glioma group (n=11) and high-grade glioma group (n=10).Each group was sampled for ultrastructural observation of the tight junctions of BBB using transmission electron microscope. Double immunofluorescence staining and RT-PCR were used to observe andanalyze the protein and mRNA expressions of Claudin-5 in the glioma, respectively. Results In normal brain tissues, the para-cellular cleft between the adjacent endothelial cells was sealed by continuous strands of tight junctions. In low-grade glioma, most of the tight junctions were intact and no fenestration was found in the endothelium. In high-grade glioma, the amount of pinocytosis vesicle was increased and significant paracellular cleft was found between the adjacent endothelial cells; in addition,typical fenestrations were found in the endothelial cells. Double immunofluorescence staining showedstrong expression of Claudin-5 in the microvascular endothelial cells in the normal brain tissues but weakexpression of that in the high-grade glioma. In the low-grade glioma, expression of Claudin-5 wasdecreased slightly in the microvascular endothelial cells. Compared with the high-grade glioma, the low-grade glioma and normal brain tissues showed significantly higher mRNA expression level of Claudin-5 (P<0.05). Conclusion In the development of brain glioma, glioma cells can decrease the expressions of Claudin-5 and interrupt the continuity of the tight junctions in BBB; and the decrease of Claudin-5 may be one of the important molecular mechanisms explaining the paracellular cleft of tight junction in BBB.