动物双歧杆菌BB-12改善全脑照射后小鼠海马神经炎症和认知功能障碍的研究  

Bifidobacterium animalis subsp. lactis BB-12 alleviates hippocampal neuroinflammation and cognitive dysfunction of mice after whole brain irradiation

作　　者：杨珊 吴连连 郭雯[3] 丁云鹤 董海北 吴小进 Yang Shan;Wu Lianlian;Guo Wen;Ding Yunhe;Dong Haibei;Wu Xiaojin(School of Chemical Engineering&Technology,China University of Mining and Technology,Xuzhou 221116,China;Animal Center of Xuzhou Medical University,Xuzhou 221004,China;Department of Radiation Oncology,Xuzhou First People′s Hospital,Affiliated Hospital of China University of Mining and Technology,Xuzhou 221002,China)

机构地区：[1]中国矿业大学化工学院,徐州221116 [2]徐州医科大学动物中心,徐州221004 [3]中国矿业大学附属医院徐州市第一人民医院放疗科,徐州221002

出　　处：《中华放射医学与防护杂志》2022年第11期823-829,共7页Chinese Journal of Radiological Medicine and Protection

基　　金：吴阶平医学基金(320.6750.2021-13-3);徐州医科大学附属医院发展基金(XYFZ2020003)。

摘　　要：目的:探讨动物双歧杆菌BB-12对全脑照射后小鼠海马神经炎症和认知功能的影响。方法:选取60只7~8周龄雄性C57BL/6J小鼠,采用完全随机法分为5组,每组12只,即健康对照组(Con组)、益生菌组(BB-12组)、单纯照射组(IR组)、照射+美金刚组(IR+Memantine组)、照射+益生菌组(IR+BB-12组)。采用医用直线加速器对小鼠行10 Gy电子线全脑照射建立放射性脑损伤模型。Y-迷宫实验评估小鼠认知功能;免疫荧光染色检测海马小胶质细胞和星形胶质细胞激活水平;实时荧光定量PCR技术(QRT-PCR)和蛋白免疫印迹(Western blot)检测海马炎症因子白介素1β(IL-1β)、IL-6和肿瘤坏死因子α(TNF-α)的表达水平。结果:Y-迷宫实验显示,与Con组相比,IR组小鼠到达新异臂的次数占3个臂总次数的百分比明显降低(t=5.04,P<0.05);BB-12可以改善放射性脑损伤后小鼠认知障碍(t=4.72,P<0.05)。与Con组相比,IR组小鼠海马区Iba1、GFAP阳性细胞数量显著增多(t=3.05、7.18,P<0.05),圆形度指数显著升高(t=6.23、2.52,P<0.05),小胶质细胞和星形胶质细胞被激活;与IR组相比,IR+BB-12组小鼠海马区Iba1、GFAP阳性细胞数量减少(t=4.80、2.90,P<0.05),圆形度指数降低(t=6.22、2.63,P<0.05),BB-12可以抑制小胶质细胞和星形胶质细胞激活。IR组小鼠海马区炎症因子IL-1β、IL-6、TNF-αmRNA和蛋白表达水平显著升高(与Con组相比:tmRNA=4.10、3.04、4.18,P<0.05;t蛋白=11.49、7.04、8.42,P<0.05);BB-12可以降低受照后IL-1β、IL-6、TNF-αmRNA和蛋白的表达水平(与IR组相比:tmRNA=4.19、3.40、2.84,P<0.05;t蛋白=6.36、4.03、3.75,P<0.05)。结论:动物双歧杆菌BB-12可抑制照射后小鼠海马区小胶质细胞、星形胶质细胞介导的神经炎症,并改善放射性认知功能障碍,具有缓解放射性脑损伤的应用潜力。Objective To investigate the effects of Bifidobacterium animalis subsp.lactis BB-12 on hippocampal neuroinflammation and cognitive function of mice after whole brain radiotherapy.Methods A total of sixty male C57BL/6J mice aged 7-8 weeks were randomly divided into 5 groups with 12 mice in each group:control group(Con group),probiotic group(BB-12 group),irradiation group(IR group),irradiation and Memantine group(IR+Memantine group),irradiation and probiotic group(IR+BB-12 group).The model of radiation-induced brain injury of mice was established by 10 Gy whole brain radiotherapy with a medical linear accelerator.Y-maze test was used to evaluate the cognitive function.The activation of microglia and astrocytes was observed by immunofluorescence staining.The expressions of inflammatory cytokines interleukin-1β(IL-1β),IL-6 and tumor necrosis factor-α(TNF-α)were detected by quantitative real-time reverse transcription polymerase chain reaction(QRT-PCR)and Western blot.Results Y-maze test showed that,compared with Con group,the percentage of the times of reaching the novel arm in the total times of the three arms decreased significantly in the IR group(t=5.04,P<0.05).BB-12 mitigated radiation-induced cognitive dysfunction(t=4.72,P<0.05).Compared with Con group,the number(t=3.05,7.18,P<0.05)and circularity index(t=6.23,2.52,P<0.05)of Iba1 and GFAP positive cells were increased,the microglia and astrocytes were activated in the hippocampus of IR group,but these alterations were eliminated by BB-12.After whole brain IR,the mRNA and protein expression levels of inflammatory cytokines IL-1β,IL-6 and TNF-αin the hippocampus of mice were significantly increased compared with Con group(tmRNA=4.10,3.04,4.18,P<0.05;tprotein=11.49,7.04,8.42,P<0.05),which were also significantly reduced by BB-12 compared with IR group(tmRNA=4.20,3.40,2.84,P<0.05;tprotein=6.36,4.03,3.75,P<0.05).Conclusions Bifidobacterium animalis BB-12 can suppress neuroinflammation mediated by microglia and astrocytes in the hippocampus of mice after radiot

关 键 词：放射性脑损伤 认知功能障碍 胶质细胞 神经炎症 动物双歧杆菌 

分 类 号：R818[医药卫生—放射医学] R749.1[医药卫生—临床医学]