CXCL13在小鼠脓毒症相关性脑病中的作用  

Role of C-X-C motif chemokine 13 in sepsis-associated encephalopathy in mice

作　　者：景灵 鲍红光[1] 曾令清[1] 耿圆 斯妍娜[1] Jing Ling;Bao Hongguang;Zeng Lingqing;Geng Yuan;Si Yanna(Department of Anesthesiology,Affiliated Nanjing Hospital,Nanjing Medical University(Nanjing First Hospital),Nanjing 210006,China)

机构地区：[1]南京医科大学附属南京医院(南京市第一医院)麻醉科,210006

出　　处：《中华麻醉学杂志》2018年第11期1388-1392,共5页Chinese Journal of Anesthesiology

基　　金：国家自然科学基金(81401620);南京市科技发展计划项目(201715033);南京市医学科技发展项目(YKK18105).

摘　　要：目的评价C-X-C家族趋化因子配体13(CXCL13)在小鼠脓毒症相关性脑病中的作用。方法健康雄性C57BL/6J小鼠64只,3~4月龄,体重20~25g,采用随机数字表法分为4组(n=16):假手术组(Sham组)、脓毒症组(S组)、CXCL13siRNA组(si-CXCL13组)和阴性对照siRNA组(si-control组)。4组腹腔注射5-溴脱氧尿嘧啶核苷(BrdU)50mg/kg,2次/d,连续3d;然后S组、si-CXCL13组和si-control组腹腔注射LPS500μg/kg制备脓毒症模型。于造模前3d时,si-CXCL13组侧脑室注射CXCL13siRNA5μl,si-control组侧脑室注射阴性对照siRNA5μl。建模后5d行Morris水迷宫实验,记录逃避潜伏期、原平台所在象限停留时间和穿越平台次数。水迷宫实验结束后处死小鼠,取海马组织,光镜下观察海马齿状回病理学结果,Western blot法检测海马CXCL13、C-X-C家族趋化因子受体5(CXCR5)和脑源性神经营养因子(BDNF)表达,免疫荧光法检测海马齿状回BrdU阳性细胞计数和BrdU/NeuroD阳性细胞计数。结果与Sham组比较,S组、si-CXCL13组和si-control组第2~4天时逃避潜伏期延长,目标象限停留时间缩短,穿越平台次数减少,海马齿状回BrdU阳性细胞计数增加,BrdU/NeuroD阳性细胞计数减少,S组和si-control组海马CXCL13和CXCR5的表达上调,BDNF表达下调,si-CXCL13组海马CXCL13和BDNF的表达下调(P<0.05);与S组比较,si-CXCL13组第2~4天时逃避潜伏期缩短,目标象限停留时间延长,穿越平台次数增加,海马齿状回BrdU阳性细胞计数减少,BrdU/NeuroD阳性细胞计数,CXCL13和CXCR5的表达下调,BDNF表达上调(P<0.05),si-control组上述各指标差异无统计学意义(P>0.05)。结论CXCL13可通过调控海马神经发生,参与小鼠脓毒症相关性脑病,其机制可能与下调海马BDNF表达有关。Objective To evaluate the role of C-X-C motif chemokine 13(CXCL13)in sepsis-associated encephalopathy in mice.Methods A total of 64 healthy male C57BL/6J mice,aged 3-4 months,weighing 20-25 g,were divided into 4 groups(n=16 each)using a random number table method:sham operation group(Sham group),sepsis group(S group),CXCL13 siRNA group(si-CXCL13 group)and negative control siRNA group(si-control group).5-bromo-2-deoxyuridine(BrdU)50 mg/kg was intraperitoneally injected twice a day for 3 consecutive days in the four groups,and then lipopolysaccharide 500 μg/kg was intraperitoneally injected to establish the sepsis model in S,si-CXCL13 and si-control groups.CXCL13 siRNA 5 μl and siRNA 5 μl were injected into the left lateral cerebral ventricle in si-CXCL13 and si-control groups,respectively,at 3 days before establishing the model.Morris water maze test was performed at 5 days after establishing the model.The escape latency,time spent in the target quadrant,and the number of crossing the platform were recorded.Mice were sacrificed after the end of test,brains were removed and hippocampi were isolated for examination of the pathological changes of the dentate gyrus(with a light microscope)and for determination of the expression of CXCL13,C-X-C motif chemokine receptor 5(CXCR5)and brain-derived neurotrophic factor(BDNF),and the number of BrdU and BrdU/NeuroD positive cells(by immunofluorescence).Results Compared with sham group,the escape latency was significantly prolonged,the time spent in the target quadrant was shortened,and the number of crossing the platform was reduced on 2nd-4th days,the number of BrdU positive cells in the dentate gyrus was increased,and the number of BrdU/NeuroD positive cells in the dentate gyrus was decreased in S,si-CXCL13 and si-control groups,and the expression of CXCL13 and CXCR5 was up-regulated,and the expression of BDNF was down-regulated in LPS and si-control groups(P<0.05).Compared with S group,the escape latency was significantly shortened,the time spent in the target quadrant

关 键 词：脓毒症 脑 趋化因子CXCL13 

分 类 号：R459.7[医药卫生—急诊医学] R747.9[医药卫生—治疗学]