摘要
目的探讨X-染色体连锁的凋亡抑制剂(XIAP)过度表达对正常凋亡相关蛋白的影响,以及XIAP对未成熟脑在缺氧缺血(HI)后硝基酪氨酸和4-羟基壬烯醛(4-HNE)形成的影响。方法新生9日龄转基因XIAP过度表达及同期野生型C57BL/6小鼠在HI(结扎左颈总动脉加10%氧气吸入55min)后3、24、72h处死,取脑组织进行硝基酪氨酸和4-HNE免疫组化染色;部分未进行HI的动物取脑组织进行匀浆用于Western蛋白印迹。结果West鄄ern蛋白印迹显示雌性转基因动物XIAP蛋白表达量高于雄性,XIAP过度表达组和野生组脑组织中细胞色素C、凋亡诱导因子、半胱天冬酶-9、半胱天冬酶-3、诱导型一氧化氮合酶、神经元型一氧化氮合酶含量差异均无显著性。免疫组化显示HI后24hXIAP过度表达组大脑皮层和海马CA1区硝基酪氨酸和4-HNE阳性细胞数明显低于野生组(P均<0.01)。结论XIAP过度表达对正常情况下凋亡相关蛋白表达无影响,其对缺氧缺血性脑损伤的保护作用可能与减轻氧化应激损伤有关。
Objectives To explore the effects of overexpression of X-linked inhibitor of apoptosis protein （XIAP） on expression of certain apoptosis-related proteins under physical condition, and nitrotyrosine and 4-hydroxy-2-noneal （4- HNE） formation in hypoxia-ischemia brain of neonatal mice. Methods 21 C57BL/6 transgenic mice with XIAP overexpression and 20 wild type mice were included in this study. Hypoxia-ischemia （HI） was induced in 9-day-old mice by ligation of the left carotid artery and 10 % oxygen being inhaled for 55 min. They were sacrificed at 3h,24 h,72 h post-HI separately and their brains were taken out at the same time. Sections of the brains were stained with antibodies against nitrotyrosine and 4-HNE. Brains of other mice not subjected to hypoxia-ischemia were homogenized and used for Western blotting. Results Western bloting showed that two bands （60 kDa and 57 kDa）were detected in the XIAP overexpression mice while only one band （60 kDa） in the wild type mice. Quantitative analysis showed the 57kDa band was much more pronounced in female mice than that of male mice （P 〈 0.02）, with no differences in total amount of cytochrome C, apopto-sis-inducing factor （AIF）,caspase-3,caspase-9,nitric oxide synthase between XIAP overexpression mice and wild type mice. However, under hypoxia-ischemia condition,there was less nitrotyrosine and 4-HNE positive cells in the cortex and CA1 region of hippocampus in XIAP overexpression mice than that of wild type mice. Conclusions Increased XIAP level did not interfere with the expression of apoptosis-related proteins in neonatal mice brain under physical condition, but can inhibit the formation of nitrotyrosine and 4-HNE after HI,indicating that neuroprotection by XIAP overexpression may be correlated to the inhibition of oxidation stress damage to brain.
出处
《临床儿科杂志》
CAS
CSCD
北大核心
2006年第9期765-769,共5页
Journal of Clinical Pediatrics
基金
国家自然科学基金(No:30470598)
