CAJ | 학술논문

目的：研究大豆异黄酮（ SI）对全脑缺血／再灌注大鼠脑组织线粒体超微结构、细胞凋亡和细胞色素C（ Cyt-C）、caspase-3及caspase-9表达的影响，探讨大豆异黄酮对脑缺血／再灌注损伤的作用及机制。方法：60只健康成年SD大鼠随机分为假手术组（ sham）、缺血再灌注组（ I／R）和大豆异黄酮预处理组（ SI）。 SI组给予SI 120 mg· kg-1· d-1连续灌胃21 d，其余2组用等体积生理盐水灌胃，每天1次，第22天I／R组和SI组行手术阻断三血管制备全脑缺血／再灌注模型。缺血1 h，再灌1 h后处死，取大脑皮层，光镜观察脑细胞形态学变化，透射电镜观察线粒体超微结构变化，流式细胞术检测细胞凋亡率，半定量RT-PCR法和免疫组织化学法测定脑组织中Cyt-C、caspase-9及caspase-3的表达。结果： I／R组线粒体膜崩解、嵴消失，脑细胞大量凋亡。与I／R组相比，大豆异黄酮预处理能明显改善线粒体超微结构的损伤，减少脑细胞凋亡率（ P＜0.01）。 I／R组Cyt-C、caspase-9和caspase-3 mRNA的表达和蛋白的含量高于sham组（P＜0.01），与I／R组相比，SI组Cyt-C、caspase-9及caspase-3 mRNA和蛋白的表达显著降低（ P＜0.01）。结论：大豆异黄酮可能通过稳定线粒体结构，减少线粒体释放Cyt-C，降低caspase-9和caspase-3的表达，抑制细胞凋亡，从而减轻脑缺血／再灌注损伤。
목적：연구대두이황동（ SI）대전뇌결혈／재관주대서뇌조직선립체초미결구、세포조망화세포색소C（ Cyt-C）、caspase-3급caspase-9표체적영향，탐토대두이황동대뇌결혈／재관주손상적작용급궤제。방법：60지건강성년SD대서수궤분위가수술조（ sham）、결혈재관주조（ I／R）화대두이황동예처리조（ SI）。 SI조급여SI 120 mg· kg-1· d-1련속관위21 d，기여2조용등체적생리염수관위，매천1차，제22천I／R조화SI조행수술조단삼혈관제비전뇌결혈／재관주모형。결혈1 h，재관1 h후처사，취대뇌피층，광경관찰뇌세포형태학변화，투사전경관찰선립체초미결구변화，류식세포술검측세포조망솔，반정량RT-PCR법화면역조직화학법측정뇌조직중Cyt-C、caspase-9급caspase-3적표체。결과： I／R조선립체막붕해、척소실，뇌세포대량조망。여I／R조상비，대두이황동예처리능명현개선선립체초미결구적손상，감소뇌세포조망솔（ P＜0.01）。 I／R조Cyt-C、caspase-9화caspase-3 mRNA적표체화단백적함량고우sham조（P＜0.01），여I／R조상비，SI조Cyt-C、caspase-9급caspase-3 mRNA화단백적표체현저강저（ P＜0.01）。결론：대두이황동가능통과은정선립체결구，감소선립체석방Cyt-C，강저caspase-9화caspase-3적표체，억제세포조망，종이감경뇌결혈／재관주손상。
[ ABSTRACT] AIM:To study the effects of soybean isoflavones on mitochondrial ultrastructure, neuronal apopto-sis and expression of cytochrome C, caspase-9 and caspase-3 in the rats with cerebral ischemia/reperfusion.METHODS:Adult healthy SD rats ( n=60 ) were randomly divided into 3 groups: sham group, ischemia/reperfusion injury ( I/R ) group and soybean isoflavone ( SI) pretreatment group.Soybean isoflavones (120 mg· kg-1 · d-1 ) were fed by gastric lav-age for 21 d.The global ischemia/reperfusion model of the rats was established by blocking 3 vessels, and then reperfused for 1 h after 1 h of ischemia.The morphological change of the cerebral cortex cells was observed under light microscope. The mitochondrial ultrastructure of the cerebral cortex cells was determined by transmission electron microscope.The apop-totic rate of the cerebral cortex cells was detected by flow cytometry.The expression of cytochrome C, caspase-9 and caspase-3 in the cerebral cortex cells was determined by semi-quantitative RT-PCR and immunohistochemical techniques. RESULTS:Disintegration of mitochondria membrane and disappearance of the mitochondrial cristae were seen in I/R group.Compared with I/R group, the change of ultrastructure of mitochondria was significantly improved by soybean isofla-vone pretreatment, and the neuronal apoptotic rate was also significantly decreased (P<0.01).The mRNA expression and protein content of cytochrome C, caspase-9 and caspase-3 in I/R group were obviously higher than those in sham group ( P<0.01).Compared with I/R group, the mRNA expression and protein content of cytochrome C, caspase-9 and caspase-3 in SI group were significantly decreased (P<0.01).CONCLUSION: Soybean isoflavones attenuate cerebral ischemia/reperfusion injury by stabilizing the structure of mitochondria, preventing cytochrome C release to the cytoplasm, inhibiting the activation of caspase-9 and caspase-3 and decreasing cell apoptosis.