宫内亚临床感染对缺氧缺血性脑损伤新生大鼠的增敏作用及其与表观遗传的关系  

Intrauterine subclinical inflammation sensitive to hypoxic - ischemia brain damage in newborn rats and the epigenetic relationship

作　　者：徐发林[1] 王彩红[1] 张彦华[1] 段佳佳[1] 郭佳佳[1] 邢秋景[1] 董慧芳[1] 李文丽[1] 

机构地区：[1]郑州大学第三附属医院儿内科,450052

出　　处：《中华实用儿科临床杂志》2015年第3期224-228,共5页Chinese Journal of Applied Clinical Pediatrics

基　　金：河南省教育厅自然科学研究计划项目（13A320664）;河南省高等学校青年骨干教师资助计划（2012ggjs-015）;郑州市科技局创新团队项目（131PCXTD621）

摘　　要：目的探讨宫内亚临床感染、出生后缺氧缺血（HI）单独及联合作用对未成熟脑发育的影响，未成熟脑损伤后组蛋白去乙酰化酶（HDACs）及HDAC1 mRNA的表达及其意义，促红细胞生产素（EPO）对未成熟大鼠脑白质损伤的保护作用。方法孕鼠分为脂多糖（LPS）组和9g／L盐水（NS）组，于孕15d分别腹腔注射LPS 0．3mg／kg或等剂量NS，继续饲养至分娩，称取出生体质量。待新生大鼠5日龄时随机数字表法分为对照组、LPS组、HI组、LPS＋HI组，干预组分LPS＋HT＋NS组和LPS＋HI＋EPO组，分别于HI后6h、24h及7d灌注取脑。酶联免疫吸附法检测脑组织中肿瘤坏死因子（TNF—α）及HDACs水平；免疫组织化学法检测微管相关蛋白-2（MAP-2）染色情况及HI后7d脑组织碱性髓鞘蛋白（MBP）的表达；实时荧光定量PCR方法检测MAP-2 mRNA及HDAC1 mRNA表达。结果LPS＋HI组TNF-α、HDACs及HDAC1 mRNA表达水平最高，MBP表达水平最低，与其他组比较差异有统计学意义（F=60．20，P〈0．05），另3组之间差异无统计学意义（P〉0．05）；LPS＋HI＋EPO组MBP水平[积分光密度（IOD）值：131．59±2．24]明显高于LPS＋HI＋NS组（IOD值：103．36±3．62），差异有统计学意义（t=16．24，P〈0．05）。LPS＋HI组MAP-2免疫组织化学染色在HI后24h显示散在坏死灶，余3组均未出现坏死灶。LPS＋HI组MAP-2mRNA损伤后6h表达降低，后逐渐升高，与其他组相比差异均有统计学意义（P均〈0．05）。结论宫内亚临床感染对出生后HI具有增敏作用；二者联合作用所导致的未成熟脑神经损伤可致表观遗传学改变。EPO对未成熟脑损伤的脑白质具有保护作用。Objective To investigate the effects of subclinical intrauterine infection, postnatal hypoxia - ischemia（HI） alone or in combination on the immature brain development, the changes and significance of histone deacetylases （HDACs） and HDAC1 mRNA after brain injury, and the protective effect of erythropoietin （EPO） on white matter injury. Methods Pregnant SD rats were randomly assigned into lipopolysaccharide（LPS） group or normal saline（NS） group, and were injected LPS （0.3 mg/kg） or the normal saline （NS） intraperitoneally at 15 days after conception, continued to raise until delivery,weighed the birth weight of the pups. The postpartum （P） day 5 rat pups were randomly divided into 4 groups ： control group, LPS group, HI group and LPS ＋ HI group ; intervention groups were divided into ： LPS ＋ HI ＋ NS group and LPS ＋ HI ＋ EPO group. The brain tissues were observed at the time point of 6 h,24 h and 7 d after HI. The expressions of tumor necrosis factor-α （TNF- α） and HDACs in the brain homogenate were measured by using enzyme - linked immunosorbent assay （ ELISA）, the levels of myelinbasicprotein （MBP） and microtubule - associated proteins（MAP） -2 were detected by using immunohistochemistry staining, the expressions of MAP -2 mRNA and HDAC1 mRNA were detected by Real - time PCR. Results The expressions of TNF - α, HDACs and HDAC1 mRNA were highest in LPS ＋ HI group ,but MBP was the lowest, and there were significant differences among LPS ＋ HI group and the other 3 groups （ F = 60. 20, P 〈 0.05 ）, and there was no difference among the other 3 groups （P 〉0.05）. The expression of MBP in LPS ＋ HI ＋ EPO group [ integrated optical density （IOD） value： 131.59 ±2.24 ] was higher than that in the LPS ＋ HI ＋ NS group（ IOD value ： 103.36 ±3.62）, and the difference was statistical- ly significant（ t = 16. 24 ,P 〈0.05）. There existed necrosis areas in the cortex of LPS ＋ HI group by MAP- 2 imnmnohistochemistry staining,w

关 键 词：未成熟脑 亚临床感染 缺氧缺血 表观遗传 促红细胞生成素 

分 类 号：R741[医药卫生—神经病学与精神病学]