坏死性小肠结肠炎对新生小鼠脑损伤及其程度的影响  

Effects of necrotizing enterocolitis on brain injury and its severity in neonatal mice

作　　者：王雪 邹谋 张绍卿 刘兰[1] 杜敏[1] 徐颖[1] WANG Xue;ZOU Mou;ZHANG Shaoqing;LIU Lan;DU Min;XU Ying(Department of Anesthesiology,National Clinical Research Center for Child Health and Disorders,Key Laboratory of Child Development and Disorders of Ministry of Education,Chongqing Key Laboratory of Pediatrics,Children’s Hospital of Chongqing Medical University,Chongqing,400014,China)

机构地区：[1]重庆医科大学附属儿童医院麻醉科,国家儿童健康与疾病临床医学研究中心,儿童发育疾病研究教育部重点实验室,儿科学重庆市重点实验室,重庆400014

出　　处：《第三军医大学学报》2021年第17期1634-1641,共8页Journal of Third Military Medical University

基　　金：重庆市技术创新与应用示范(社会民生类)一般项目(cstc2018jscx-msybX0104)。

摘　　要：目的探讨不同程度坏死性小肠结肠炎(necrotizing enterocolitis,NEC)对新生小鼠脑损伤的影响。方法将60只5日龄C57BL/6小鼠随机分为对照组(CON组,n=20)和坏死性小肠结肠炎组(NEC组,n=40)。CON组与母鼠同笼,母乳喂养;NEC组饲养在保育箱,采用配方奶喂养+缺氧+口服脂多糖(LPS)诱导坏死性小肠结肠炎小鼠模型,建模4 d后处死所有小鼠。建模过程中记录小鼠每日体质量并观察一般情况;HE染色观察肠道组织的病理学改变。根据回盲部肠道损伤评分将NEC组分为轻度NEC组(n=12)和重度NEC组(n=12);Nissl染色观察相应脑组织的病理学变化,并将肠道损伤程度和神经细胞的数量做相关性分析。RT-qPCR检测脑组织中炎症因子IL-1β、IL-6和TNF-αmRNA的表达水平;酶联免疫吸附法(ELISA)检测脑组织炎症因子IL-1β、IL-6和TNF-α蛋白的表达水平;免疫荧光检测活化的小胶质细胞和星形胶质细胞的数量。结果与CON组相比,NEC组小鼠活动度降低,体质量明显减轻(3.84±1.25 vs 1.76±0.26 g,P<0.05),肠道损伤严重,且在海马CA1区,轻、重度NEC组的神经细胞数量减少(125.83±6.40 vs 103.83±7.93、75.50±8.87,P<0.05),重度NEC组较轻度NEC组减少更多(P<0.05);相关性分析显示:神经细胞数量与肠道损伤的严重程度呈负相关(r=-0.943,P<0.001)。与CON组相比,NEC组脑组织炎症因子IL-1β、IL-6和TNF-ɑ的表达水平均升高(P<0.05),活化的小胶质细胞和星形胶质细胞也明显增多(P<0.05),并且重度NEC组较轻度NEC组升高更明显(P<0.05)。结论坏死性小肠结肠炎可导致新生小鼠发生急性脑损伤,其损伤程度与肠道损伤的严重程度相关,可能与神经炎症的增加有关。Objective To investigate the effect of necrotizing enterocolitis(NEC)at different severities on brain injury in neonatal mice.Methods Sixty 5-day old C57BL/6 mice were randomly divided into control group(CON group,n=20)and NEC group(n=40).The CON group was breeding with female mice and breastfed.The NEC group was fed in an incubator,and induced by formula gavage feeding+hypoxia+oral lipopolysaccharide(LPS)to establish the model of NEC.In 4 d after NEC modeling,all pups were sacrificed by cervical decapitation.Their body weight was measured and general conditions were observed.HE staining was used to observe the pathological changes of intestinal tissue.NEC group was divided into mild NEC subgroup and severe NEC subgroup according to the intestinal injury score of ileocecus.Nissl staining was employed to further observe the pathological changes of the corresponding brain tissue.The correlation between the severity of intestinal injury and the number of nerve cells was analyzed with Pearson analysis.The mRNA levels of the inflammatory factors interleukin-1β(IL-1β),IL-6 and tumor necrosis factor-α(TNF-α)in brain tissues were measured with quantitative real-time PCR(RT-qPCR).Enzyme-linked immunosorbent assay(ELISA)was adopted to detect the protein contents of IL-1β,IL-6 and TNF-αin brain tissues.Immunofluorescence assay was conducted to detect the number of activated microglia and astrocytes in the hippocampus.Results Compared with CON group,the NEC group had decreased activities and lower body weight(3.84±1.25 vs 1.76±0.26 g,P<0.05),and serious intestinal damage.The number of nerve cells in the hippocampus were significantly reduced in the NEC group than the CON group(P<0.05),so was in the severe NEC subgroup than that the mild NEC subgroup(P<0.05).Correlation analysis showed that the pathological changes of brain were negatively correlated with the severity of intestinal injury(r=-0.943,P<0.001).When compared with the CON group,the mRNA and protein levels of IL-1β,IL-6 and TNF-αin brain tissues were signi

关 键 词：坏死性小肠结肠炎 早产儿 神经炎症 脑损伤 

分 类 号：R-332[医药卫生] R725.746.2